ARTICLE | doi:10.20944/preprints202011.0506.v1
Subject: Mathematics & Computer Science, Algebra & Number Theory Keywords: sleep stage classification; ECG, nested–cycle sleep pattern; stage transition
Online: 19 November 2020 (11:10:07 CET)
：Sleep stage on the whole night is not steady. Sleepers generally pass through three to five cycles. In each cycle, there are occur four typical sleep stages, such as wake stage (WS), light stage (LS), deep sleep (DS), rapid eye movement sleep stage (REM). According to the natural routine, in this paper, we investigate the stage transition and analyze the feature of stage transition using the local cluster Algorithm (LCA). Two-cycle sleep model (TCSM) is proposed to automatically classify sleep stages using over-night continuous heart rate variability (HRV) data. The generated model is based on the characteristics of the nested cycle's sleep stage distribution and the transition probabilities of sleep stages. Experiments were conducted using a public data set including 400 healthy subjects (female 239, male 161) and the model’s classification accuracy was evaluated for four sleep stages: WS, LS, DS, REM. The experimental results showed that based on the TCSM model, the segmentation classification of pure sleep is 5.2% higher than that of the traditional method, and the accuracy of segmentation classification is 11.2% higher than the traditional sleep staging accuracy. The experimental performance is promising in terms of the accuracy, sensitivity, and specificity rates compared with the ones of the state-of-the-art methods. The study contributes to improve the quality of sleep monitoring in daily life using easy-to-wear HRV sensors.
ARTICLE | doi:10.20944/preprints202107.0617.v1
Subject: Behavioral Sciences, Applied Psychology Keywords: Sleep duration; sleep latency; sleep efficiency; health behaviour
Online: 28 July 2021 (10:17:01 CEST)
Growing evidence suggests sleep plays an important role in the development of healthy adolescents, with increased interest in the associations between sleep and mental health. Higher duration and quality of sleep has been suggested as a mechanism for increased wellbeing in adolescents. Cross sectional data was collected from 5,661 Irish adolescents. 55% of Irish adolescents reported meeting the guidelines for adolescents of 8-10 hours per night. This was found to decrease with age. Higher duration and quality of sleep was positively associated with wellbeing and negatively associated with symptoms of anxiety and depression. A higher frequency of physical activity was associated with longer duration and higher quality of sleep. 9-10 hours of sleep was associated with the highest levels of wellbeing and lowest symptoms of anxiety and depression. The relationship between physical activity and increased wellbeing may be impacted by physical activity leading to higher durations and quality of sleep.
ARTICLE | doi:10.20944/preprints202303.0149.v1
Subject: Behavioral Sciences, General Psychology Keywords: Sleep cycle; Sleep pills; Sleep habits; Covid 19; Students; PSQI
Online: 8 March 2023 (08:36:06 CET)
The alterations in sleep among undergraduate students have been a burden to their mental health and academic studies. We used the Pittsburgh Sleep Quality Index scale in this study conducted among Georgian and International students. The respondents participated in this study through the University intranet as their responses remained anonymous. The survey comprised the demographic characteristics and sleep health deteriorating wake patterns such as subjective sleep quality, sleep latency, sleep duration, habitual sleep efficiency, sleep disturbances, use of sleeping medication, and daytime dysfunction. A total of 500 students completed this study, 72% were Georgian students, and 28% were international students. 50.8% of Georgian students were under the age of 20 years, and 74.3% of international students were between 21 and 30 years of age. Most Georgian students reported poor subjective sleep quality, short sleep duration, fewer sleep disturbances, and daytime dysfunction. However, sleep latency was higher among international students. Both categories of students reported using sleeping pills as the statistical significance was observed between global score and gender, subjective sleep quality, and age grade of Georgian students (p<0.05). This study aimed to evaluate the sleep-wake health quality among international and Georgian undergraduate students at the University of Georgia.
REVIEW | doi:10.20944/preprints201911.0387.v2
Subject: Behavioral Sciences, Behavioral Neuroscience Keywords: evolutionary bottleneck; evolution of sleep; sleep variability; function of sleep
Online: 20 July 2020 (10:31:23 CEST)
The Nocturnal Bottleneck explains how mammals evolved from their reptilian ancestors after inverting the chronotype, form diurnal to nocturnal. Pre-mammals traded-off the excellent visual system of their ancestors for improvements in audition and in olfactory telencephalon, needed for efficient orientation in the dark. This was how the mammalian nocturnal telencephalic wakefulness was born. However, the modified visual system of those pre-mammals became sensitive to the dangerous diurnal light and the exposure would involve a high risk of blindness and death. Therefore, pre-mammals had to remain immobile with closed eyes hidden in lightproof burrows during light time. This was the birth of the mammalian sleep. Typical reptiles distribute their wake time cycling between Basking Behavior, to attain the preferred body temperature, and poikilothermic Goal Directed Behavior, to perform life sustaining tasks. These cycles persisted during the new mammalian sleep. However, as the behavioral output had to be blocked during light time, the paralyzed reptilian Basking Behavior and Goal Directed Behavior cycles became the NREM and REM cycles, respectively. This was how NREM and REM cycles remained incorporated within the mammalian sleep. After the Cretaceous-Paleogene extinction, the environmental pressure for nocturnal life was softened, allowing high variability in chronotype and sleeping patterns. This permitted some mammalian groups, e.g., primates, to begin the quest for diurnal wake.Concluding, sleep constituted an additional bottleneck in the mammalian evolution. The reduced population of pre-mammals that was able to develop sleep during light time, including NREM and REM, became full mammals and survived; the remainder perished.
ARTICLE | doi:10.20944/preprints201812.0318.v1
Subject: Behavioral Sciences, Behavioral Neuroscience Keywords: Subjective sleep assessment; Autism spectrum disorder; REM sleep; NREM sleep
Online: 27 December 2018 (10:21:06 CET)
Sleep disturbances very common in children with autism. That is why it requires instruments that facilitate its evaluation. Goals: Perform the evaluation of sleep from a subjective prospect in a group of children with primary autism and compare to a control group, using the Sleep Habits in Children Survey (CSHQ), In order to determine sleep disturbances, according to the sub-scales results. Method: A prospective cross-sectional study of the sample was carried out. A group with primary Autism n = 21 was selected. For the assessment of the dream we chose (CSHQ). The differences between independent groups were calculated by applying a Mann Whitney U test (p <0.05). Results: The group of children with autism showed the highest values of the total scale (mean = 48.00) wish is congruent with a greate disfuntion of sleep, compared to the control group (mean = 36.47) for p = 0.00. Significant differences were found for all sub scales p = 0.00, with the exception of sub-scale number 7. Conclusions: There is a high presence of sleep disturbances in children with primary autism, which are related to multifactorial causes, with the exception of sleep breathing disorders that did not show statistically significant differences between groups.
ARTICLE | doi:10.20944/preprints202107.0118.v1
Subject: Behavioral Sciences, Applied Psychology Keywords: sleep depth; sleep duration; sleep timing; time zones; COVID-19; aviation
Online: 5 July 2021 (16:18:13 CEST)
Fatigue risk to commercial pilots operating under global pandemic conditions had not been in-vestigated prior to COVID-19. Examining how pilots slept during COVID-19 pandemic-specific flights can provide a precedent for estimating fatigue risk for future public health emergencies. Twenty (n=20) pilots flying across five COVID-19 humanitarian missions between Brazil and China wore a sleep-tracking device (the Zulu watch), which has been validated for the estimation of sleep timing (sleep onset and offset), duration, efficiency, and sleep depth (Wake, Interrupted, Light, or Deep Sleep) throughout the mission period. Pilots also reported sleep timing, duration and subjective quality of their in-flight rest periods using a sleep diary. To our knowledge, this is the first report of commercial pilot sleep behavior during ultra-long-range operations under COVID-19 pandemic conditions. Moreover, these analyses provide an estimate of sleep depth during in-flight sleep, which has not been reported previously in the literature.
REVIEW | doi:10.20944/preprints201809.0100.v1
Subject: Medicine & Pharmacology, Other Keywords: Hospitalized patients, sleep wake dysfunction, sleep disorders, circadian rhythm, sleep apnea
Online: 5 September 2018 (14:49:34 CEST)
Hospitalized patients frequently have disordered and poor-quality sleep due to a variety of both intrinsic and extrinsic factors. These include frequent nighttime intrusions, insomnia related to pain and unfamiliar environments, dark conditions during the day with loss of natural light, and disruption of natural sleep cycle due to illness. Sleep wake disturbances can result in deleterious consequence on physical, emotional and cognitive status, which may impact patient satisfaction, clinical recovery, and hospital length of stay. Despite this, clinicians frequently fail to document sleep disturbances and are generally unaware of best practices to improve sleep quality in the hospital. The purpose of this review is to discuss sleep disturbances in hospitalized patients with a focus on causes of sleep disturbance, effect of poor quality sleep, high risk populations, considerations for surveillance and prevention, as well as pharmacologic and non-pharmacologic options for treatment.
CASE REPORT | doi:10.20944/preprints202102.0285.v1
Subject: Medicine & Pharmacology, Allergology Keywords: Clear Aligners; Maxillomandibular advancement; sleep apnea; intermaxillary advancement; sleep surgery; sleep medicine
Online: 11 February 2021 (13:20:43 CET)
Maxillomandibular advancement (MMA) is a surgical intervention that reduces the symptoms of obstructive sleep apnea via anterior repositioning of the upper and lower jaws. Pre-operative orthodontic alignment is often a critical component in aiding MMA. Orthodontia are important in intraoperative anchorage for intermaxillary fixation, healthy post-operative occlusion, and post-operative skeletal stability. Sequential clear aligners (SCA) refer to removable orthodontic appliances that are replaced at regular intervals to stimulate dental migration without the use of bonded hardware. These aligners have demonstrated efficacy in aiding orthognathic surgery for dentofacial deformities, which share some technical similarities with MMA for OSA. Here, we explore the treatment protocol for MMA followed by post-operative SCA treatment. Our experiences show that post-operative orthodontic treatment with SCAs results in similarly successful post-operative surgical outcomes given that the patient’s pre-operative occlusion is stable.
ARTICLE | doi:10.20944/preprints202110.0190.v1
Subject: Medicine & Pharmacology, General Medical Research Keywords: Sleep habits; Sleep disorders; Students: Academic achievement.
Online: 13 October 2021 (08:26:58 CEST)
Sleep deprivation (failure to get enough sleep) is a public health issue that can negatively impact our body including cognitive function. Many studies have been done in Saudi Arabia to evaluate the impact of poor sleep and academic performance but almost all of them were done at university level. To investigate the relationship between sleep quality and general degree of academic achievement in school students. This is a cross-sectional, school-based study, conducted at Jazan Region, Saudi Arabia. A total of 957 participants (615 male and 342 female) were recruited from a state school. The study used a standardized, confidential, validated self-administered questionnaire to assess sleep quality and habits. By using Statistical Package for Social Studies (SPSS 22), achievement of the students was significantly related to the following parameters; laziness and fatigue after wake-up time and during school time, lack of concentration during school time, difficulty in complete tasks during school time and inability to maintain wakefulness during school time. Furthermore, students with poor academic degrees reported more significant incidence of sleeping at school, excessive daytime sleepiness, and other sleep related disorder than good academic degrees. Students with poor sleep quality have lower school grades.
REVIEW | doi:10.20944/preprints201802.0146.v1
Subject: Medicine & Pharmacology, Psychiatry & Mental Health Studies Keywords: schizophrenia; psychosis; sleep; sleep disturbances; sleep disorders; integrative medicine; acupuncture; add-on therapy
Online: 23 February 2018 (04:59:52 CET)
Background: Schizophrenia is a severe psychiatric disorder that has a large impact on patients’ lives. In addition to Western medicine, the use of additional treatments, such as acupuncture, in treating the positive, negative, and cognitive symptoms is increasing. Methods: We conducted a systematic review on the use of acupuncture as an add-on treatment for patients with schizophrenia that are in regular care, with a special focus on the treatment of the often accompanying co-morbid sleep disorders. In this study, we searched the Medline, ScienceDirect, Cochrane Library, Scopus, and ERIC databases with a cut-off date of December 31, 2017, thereby following the guidelines of the Preferred Reporting Items for Systematic Reviews and Meta-analysis (PRISMA) protocol. Results: Our search resulted in 26 eligible studies. Most studies showed limited evidence for the use of acupuncture as add-on therapy in the treatment of clinical symptoms, but beneficial effects have been reported in the treatment of co-morbid sleep disorders. Conclusions: Limited evidence was found for the use of acupuncture as add-on therapy in the treatment of patients with schizophrenia; however, positive results were found in the treatment of sleep disorders, but this result needs to be confirmed in large, randomized, controlled trials.
REVIEW | doi:10.20944/preprints202103.0261.v1
Subject: Behavioral Sciences, Applied Psychology Keywords: Evolution of sleep, NREM sleep, REM sleep, Rhombencephalic-spinal wake, Diencephalic wake, Cortical wake
Online: 9 March 2021 (11:12:11 CET)
Three types of wakefulness appeared along the vertebrate’s phylogeny and ontogeny: spinal-rhombencephalic in fish, brainstem-diencephalic in reptiles and cortical in mammals, in which the paralyzed spinal-rhombencephalic wake and the brainstem-diencephalic wake remain as REMS and NREMS The spinal-rhombencephalic and cortical types of wake are inherently anti-homeostatic. Animals must forage, reproduce, and survive to predation disregarding the environmental circumstances, hence temporarily forgetting the homeostatic regulation. After fulfilling the vital functions, the brainstem-diencephalic wake recovers the homeostatic control. The phasic signs of REMS are adaptive in immature mammals, serving for demanding heat, milk and defense to their mother. These advantages outweigh the REMS' poikilostasis in infants. The adults’ poikilostasis of REMS is harmless in thermoneutral environments but is mal-adaptive in aquatic environments in which REMS is reduced or even disappears. These exceptions explain the anomalous examples of REMS. An on-off hypothalamic switch homeostatically regulates the entrance and exit from REMS. Furthermore, the vital phasic signs of REMS depend on a second pontine proportional homeostatic control. Altogether, they regulate the expression of REMS.
ARTICLE | doi:10.20944/preprints201904.0325.v1
Subject: Biology, Other Keywords: sleep; anesthesia; rapid eye movement (REM) sleep; NREM sleep; sharp-wave ripples (SWRs); dreaming; consciousness
Online: 30 April 2019 (11:12:47 CEST)
Sleep is still considered a mystery, despite intense scientific investigation. Here we present the first complete biological theory of sleep. The role of sleep is to restore the optimal homeostatic state, which is essential for tissue performance and health. Non-rapid eye movement sleep (NREMS) restores cortical and most other brain neurons, via relaxed global activity managed by thalamocortical circuits. The role of REM sleep is to restore acetylcholine (ACh) neurons, which support focused responses and hence cannot participate in global oscillations. Sleep enhances learning and memory via state restoration and ACh-affected paths. NREMS induces a lack of consciousness because global synchronous activity prevents focused responses, which are essential for consciousness. Dreams result from focused neural firing during sharp-wave ripples and REMS, and have a sense of reality because they involve the same neurons representing focused perceptual responses during wake. Anesthetics utilize a variety of mechanisms that prevent focused responses.
ARTICLE | doi:10.20944/preprints201808.0369.v4
Subject: Medicine & Pharmacology, Other Keywords: schizophrenia; impaired neurogenesis; sleep-wake cycle; non-REM sleep
Online: 20 November 2018 (07:06:35 CET)
Through the use of a simplified model of consciousness this paper illustrates the symptoms of schizophrenia linked to neocortical structures and functions. It makes the case that the bewildering and varied presentation of symptoms in schizophrenia can be analyzed and explained using such models. The model is used to illustrate the central thesis of the paper, that schizophrenia is a disorder of neurogenesis which leads to progressive neurochemical, functional and neurophysiological changes that create the characteristic behaviors of the disease.
ARTICLE | doi:10.20944/preprints202010.0256.v1
Subject: Medicine & Pharmacology, Allergology Keywords: workplace health promotion; sleep quality; sleep hygiene; sleepiness; safety; insomnia; sleep deprivation; accidents; near miss; police
Online: 12 October 2020 (16:27:57 CEST)
A workplace sleep health promotion program was implemented in an Italian police unit from 2016 to 2017. Of the 242 police officers in the unit, 218 (90%) agreed to take part in the program. A crossover trial was made in which the police officers were divided into two groups that performed sleep health promotion activities in the first and second year, respectively. The first group of officers showed significant sleep improvements at the end of the first year, while the second group had similar or worse parameters than at baseline. At follow-up, a significant improvement in the quantity and quality of sleep was reported in both groups. Sleep improvements at follow-up were associated with a marked reduction in the frequency of accidents at work and near-misses. All sleep parameters showed a significant association with injuries and near-misses in univariate logistic regression analyses. Before the intervention, sleepiness was the best predictor of injuries (aOR 1.220; CI95% 1.044-1.426) and near-misses (aOR 1.382; CI95% 1.182-1.615). At follow-up, when sleep conditions had improved, insomnia symptoms were the most significant predictors of work accidents (aOR 13.358; CI95% 2.353-75.818). Sleep health promotion can be useful in police officers.
ARTICLE | doi:10.20944/preprints201907.0303.v1
Subject: Engineering, Biomedical & Chemical Engineering Keywords: wrist-worn devices; sleep trackers; activity trackers; sleep classification; polysomnography
Online: 26 July 2019 (17:13:36 CEST)
Commercial sleep devices and mobile-phone applications for scoring sleep are gaining ground. In order to provide reliable information about the quantity and/or quality of sleep, their performance needs to be assessed against the current gold-standard, i.e. polysomnography (PSG; measuring brain, eye and muscle activity). We here assessed some commercially available sleep trackers, namely; a commercial activity tracker: Mi band (Xiaomi, BJ, CHN), a scientific actigraph: Motionwatch 8 (CamNTech, CB, UK), and a much used sleep application: Sleep Cycle (Northcube, GOT, SE). We recorded 27 nights in healthy sleepers using PSG and these devices. Surprisingly, all devices had very poor agreement with the gold standard. Sleep parameter comparisons revealed that specifically the Mi band and the sleep cycle application had difficulties in detecting wake periods which negatively affected the total sleep time and sleep efficiency estimations. However, all 3 devices were good in detecting the most basic parameter, the actual time in bed. In summary, our results suggest that, to-date; available sleep trackers do not provide meaningful sleep analysis but may be interesting for simply tracking times in bed. A much closer interaction with the scientific field seems necessary if reliable information shall be derived from such devices in the future.
ARTICLE | doi:10.20944/preprints202303.0162.v1
Subject: Behavioral Sciences, Other Keywords: Consumer Sleep Technologies; Wearables; Sleep-Tracking; Behavioral Economics; Demand Curve Analysis
Online: 9 March 2023 (02:18:22 CET)
The goal of this report was to examine the behavioral economic demand for consumer sleep technologies with different levels of validation and endorsement. The value or importance consumers place in different validation methods and the organizations conducting the evaluations was also assessed. Survey data were collected from 113 participants on Amazon mTurk. Participants indicated their likelihood of purchasing devices that varied in level of validation across a series of increasing prices. Demand curves were analyzed to determine the relative value of each watch type. Participants also reported how valuable or important different aspects of device validation were to them. Devices that were both evaluated against laboratory measures and endorsed by sleep researchers had the most value, followed by those only evaluated against laboratory measures, and then those not evaluated against any laboratory measures. The unit price at which there was 50% probability of purchase was increased by $25 or $44 for evaluation or endorsement, respectively. Respondents indicated the most valuable features were a measure of sleep duration, that it was most important that devices were validated against measures of sleep from a laboratory or hospital, and that they would put a high value on sleep tracker endorsements from a university or academic institution. Consumer demand is greatest for a device that has been evaluated by an independent laboratory for accuracy in measuring sleep and is endorsed by an academic, medical, or government institution. These results indicate a role for scientific evaluation and endorsement in consumer preference for sleep trackers.
ARTICLE | doi:10.20944/preprints202207.0451.v1
Subject: Medicine & Pharmacology, General Medical Research Keywords: sleep deficiency; insufficient sleep; surgery; surgical complications; attending surgeon; surgical outcomes
Online: 29 July 2022 (06:27:15 CEST)
Background: Sleep deficiency can adversely affect the performance of resident physicians resulting in greater medical errors. However, the impact of sleep deficiency on surgical outcomes, particularly among attending surgeons is less clear. Methods: Sixty attending surgeons from academic and community departments of surgery or obstetrics and gynecology were studied prospectively using direct observation and self-report to explore the effect of sleep deprivation on patient safety, operating room communication, medical errors, and adverse events while operating under two conditions, Post-Call (defined as >2 hours of nighttime clinical duties) and Non-Post-Call. Results: Each surgeon contributed up to five surgical procedures post-call and non-post-call yielding 362 cases total (150 Post-Call and 210 Non-Post-Call). Most common were caesarian section and herniorrhaphy. Hours of sleep on the night before the operative procedure were significantly less Post-Call (4.98 ± 1.41) vs. Non-Post-Call (6.68 ± 0.88, p<0.01). Errors were infrequent and not related to hours of sleep or post-call status. However, Non-Technical Skills for Surgeons (NOTSS) ratings demonstrated poorer performance while Post-Call for Situational Awareness, Decision Making and Communication/Teamwork. Fewer hours of sleep also was related to lower ratings for Situational Awareness and Decision Making. Decreased self-reported alertness was observed to be associated with increased procedure time. Conclusions: Sleep deficiency in attending surgeons was not associated with greater errors during procedures performed during the next day. However, procedure time was increased suggesting that surgeons were able to compensate for sleep loss by working more slowly. Ratings on non-technical surgical skills were adversely affected by sleep deficiency.
ARTICLE | doi:10.20944/preprints202009.0354.v1
Subject: Medicine & Pharmacology, General Medical Research Keywords: sleep apnoea; obstructive sleep apnoea; polysomnography; excessive day time sleepiness; obesity
Online: 16 September 2020 (07:19:33 CEST)
Objective: Identify factors associated with excessive day time sleepiness (EDS) in individuals with obstructive sleep apnea (OSA), and analyze the effects that obesity and gender have on excessive daytime sleepiness in such individuals. Methods: A total of 160 people were selected for this study. All the people have completed a clinical evaluation, and whose apnea-hypopnea index (AHI) > 10 events/hour of sleep on polysomnography were included in the study from the Department of otolaryngology. Results: The Mean age was 43.87±11.34 years, mean EDS score was 14.09± 4.91, and mean AHI was 43.88±20.66 events/hour of sleep. Male presented lower mean age, higher EDS scores, and more time in apnoea, whereas females presented with higher mean age, lower EDS scores, and less time in sleep apnea. The EDS score showed best correlation with duration of apnoea (r = 0.448; p < 0.01), peripheral oxygen saturation (SpO2; r = -0.458; p < 0.01) and AHI (r = 0.484; p < 0.01). The mean body mass index (BMI) was 27.41±3.86 kg/m2. Normal, Overweight, obese, and morbidly obese were observed in 20%, 61%, 18%, and 0.6% of cases, respectively. Severity of the disease best correlated with BMI (r = 0.421; p < 0.01). Conclusions: OSA is predominant in males (M/F 5:1), and obese population. Females diagnosed with OSA have higher mean age. However, EDS scores and time spent in sleep apnoea is lower in females. Higher BMI is associated with EDS, irrespective of gender.
ARTICLE | doi:10.20944/preprints202206.0138.v1
Subject: Life Sciences, Biophysics Keywords: posturography; insomnia; sleep disorders
Online: 9 June 2022 (08:11:21 CEST)
Lack of sleep is a factor that disrupts the receptors' reception of information from the environ-ment and contributes to the emergence of problems with maintaining balance. The main pur-pose of this study was to find out whether Computer Dynamic Posturography could be a useful tool in distinguishing between people who sleep well from people with insomnia. The study participants were 76 male students who were divided into groups based on the results obtained from the Pittsburgh Sleep Quality Questionnaire. In each group, postural stability had been tested using three main tests: Strategy Organization Test SOT, Motor Control Test MCT and Ad-aptation Test ADT. The results of the analysis show that the obtained results differ in the exam-ined groups under the SOT test. Among people with insomnia, higher values of the tested pa-rameters were noted, than with people who sleep well, which translates into a worse ability to maintain balance. The greatest impact is observed when using eyesight and a vestibular system to maintain a stable posture. It was confirmed that Computer Dynamic Posturography is used to differentiate between people who sleep well from people with insomnia in the group of men. Lack of sleep significantly disturbs postural stability.
ARTICLE | doi:10.20944/preprints201908.0208.v3
Subject: Behavioral Sciences, Cognitive & Experimental Psychology Keywords: sleep; memory; consolidation; napping; fatigue
Online: 13 January 2023 (10:52:30 CET)
Understanding the complex relationship between sleep and memory is a major challenge in neuroscience. Many studies on memory consolidation in humans suggest that sleep triggers offline memory processes, resulting in less forgetting of declarative memory and performance stabilization in non-declarative memory. However, an increasing number of contradictory findings reveal potential issues with how research is conducted in this field and call into question the reliability and interpretation of the results. All scientific disciplines face similar challenges. In this regard, research on the relationship between sleep and memory is still very fortunate. Yet, there is a constant need to fine-tune the methodology. In this article, we describe four behavioral methodological issues in human sleep and memory research that should be improved: non-optimal experimental designs, task complexity, fatigue effects in repetitive tasks, and inappropriate data analysis practices. We then offer solutions to each of these issues. We believe that implementing these solutions in future sleep and memory research will lead to more reliable results and significantly advance our understanding in this field.
REVIEW | doi:10.20944/preprints202106.0581.v1
Subject: Medicine & Pharmacology, Allergology Keywords: atopic dermatitis; melatonin; sleep disturbances
Online: 23 June 2021 (12:27:32 CEST)
Atopic dermatitis (AD) is common inflammatory dermatosis, typically with chronic and recurrent course, which significantly reduces the quality of life. Sleep disturbances are considered to be remarkably burdensome ailments in the patients with AD, and are routinely included during assessment of disease severity. Therefore, endogenous substances engaged in the control of circadian rhythms might be important in pathogenesis of AD and, possibly, be used as biomarkers of disease severity or even in development of novel therapies. Melatonin (MT), the indoleamine produced by pineal gland (but also by multiple other tissues, including skin), plays a pivotal role in maintaining the sleep/wake homeostasis. Additionally, it possess strong antioxidant and anti-inflammatory properties, which might directly link chronic skin inflammation and sleep abnormalities characteristic of AD. The objective of this work is to systematically present and summarize the results of studies (both experimental and clinical) that investigated the role of MT in the AD, with focus on the antioxidant and immunomodulatory effects of MT.
COMMUNICATION | doi:10.20944/preprints202005.0446.v1
Subject: Keywords: sleep; allometric scaling; oxidative stress
Online: 27 May 2020 (08:29:53 CEST)
Why animals sleep is an outstanding open question. Information about the toxic byproducts of aerobic cellular respiration along with the analysis of patterns in animal size, sleep needs, dietary-type, metabolism, number of heart beats, transportation-network design, and transportation energetics/dynamics suggest that the function of sleep is to maximize the time an animal has to perform its life functions given the finite and constant number of lifetime heart beats it has. Sleep slows down metabolism, and the heart rate, thereby decreasing the load of toxic reactive oxygen species in the cell and extending the cell’s lifetime/proper-functioning. I argue that this is used to maximize the time an animal spends in its ‘effective environment’, which is defined as the period in the light cycle (day or night) where the essential life-functions of that animal (like finding resources, finding sex, hunting) are better achieved. Larger, slow-metabolizing animals need less sleep because their large-bodily-networks and slow metabolisms keep their heart rates relatively low, resulting in a lower rate of oxidative damage, and more relative time in the ‘effective environment’ to get their essential life-functions accomplished.
ARTICLE | doi:10.20944/preprints202112.0489.v1
Subject: Behavioral Sciences, Applied Psychology Keywords: sleep; academic performance; grade point average; college students; wearable device; longitudinal; nighttime sleep awakening
Online: 30 December 2021 (13:45:37 CET)
Although the relations between sleep and academic performance have been extensively examined, how sleep predicts future academic performance (e.g., 2 -3 years) remains to be further investigated. Using wearable smartwatches and a self-report questionnaire, we tracked sleep activities of 45 college students over a period of approximate half a month to see whether their sleep activities predicted their academic performance, which was estimated by grade point average (GPA). Results showed that both nighttime sleep awakening frequency and its consistency in the tracking period were not significantly correlated with the GPA for the courses taken in the semester during sleep tracking (current GPA). However, both nighttime sleep awakening frequency and its consistency inversely predicted the GPA for the rest of the courses taken after that semester (future GPA). Moreover, students with more difficulty staying awake throughout the day obtained lower current and future GPAs, and students with lower inconsistency of sleep quality obtained lower future GPA. Together, these findings highlight the importance of nighttime sleep awakening frequency and consistency in predicting future academic performance and emphasize the necessity of assessing the consistency of sleep measures in future studies.
ARTICLE | doi:10.20944/preprints202112.0446.v1
Subject: Medicine & Pharmacology, Other Keywords: sleep breathing disorders; mandibular advancement; MAD; titratable positioner; drug-induced sleep endoscopy; patient selection.
Online: 28 December 2021 (11:03:45 CET)
Mandibular advancement devices (MAD) are an effective alternative treatment to CPAP. However, different maneuvers have been performed during the performance of drug sleep-induced endoscopy (DISE) to mimic the effect of MAD. Using the Selector Avance Mandibular (SAM) device, we aimed to identify MAD candidates during DISE using a titratable, reproducible, and measurable maneuver. This DISE-SAM protocol may help to find the relationship between the severity of the respiratory disorder and the degree of response, and to determine the advancement required to improve the collapsibility of the upper airway. Explorations were performed in 161 patients (132 males; 29 females) with a mean age of 46.81 (SD = 11.42) years, a BMI of 27.90 (SD = 4.19) kg/m2 and a mean AHI of 26.51 (SD = 21.23). Results showed no relationship between severity and MAD recommendation. Also, there was a weak positive relationship between the advancement required to obtain a response and the disease severity. Using the DISE-SAM protocol, the response and the range of mandibular protrusion were assessed, avoiding the inter-examiner bias of the jaw thrust maneuver. We suggest prescribing MAD as a single, alternative, or multiple treatment approaches following the SAM recommendations in a personalized design.
REVIEW | doi:10.20944/preprints202108.0551.v1
Subject: Medicine & Pharmacology, Nutrition Keywords: Obstructive sleep apnoea; intermittent airway obstruction; sleep disorder; magnesium; micronutrient deficiency; metabolic risk factor
Online: 30 August 2021 (15:47:33 CEST)
Purpose: Obstructive sleep apnoea (OSA) affects patients’ quality of life and health. Magnesium (Mg) is an essential mineral and a potent antioxidant. Mg deficiency can worsen oxidative stress caused by sleep deprivation or disorders. The impact of OSA on serum Mg levels and its health consequences remain unclear. Methods: This study systematically reviewed clinical studies investigating the serum Mg levels of OSA patients and the potential relationships with other biomarkers.Results: Six articles were included for qualitative synthesis; five were used in quantitative analysis. Two out of four studies that compared OSA patients to healthy controls found them to have significantly lower serum Mg levels. Our meta-analysis with three studies shows that patients with OSA had significantly lower serum Mg with an effect size of -1.22 (95% CI: -2.24, -0.21). However, the mean serum Mg level of OSA patients (n=251) pooled from five studies (1.90 mg/dL, 95% CI: 1.77, 2.04) does not differ significantly from the normal range. OSA severity appears to affect serum Mg negatively. Serum Mg levels generally improve after treatment, coincide with the improvement of OSA severity. Low serum Mg levels correlate with worsening of cardiovascular risk biomarkers of C-reactive protein, ischaemia-modified albumin, and carotid intima-media thickness. The serum Mg levels also potentially correlate with biomarkers for lipid profile, glucose metabolism, calcium and heavy metals. Conclusions: Sleep deprivation appears to deplete Mg levels of OSA patients, making them at risk of Mg deficiency, which potentially increases systemic inflammation and the risk of cardiovascular and metabolic diseases.
REVIEW | doi:10.20944/preprints201811.0506.v2
Subject: Medicine & Pharmacology, Psychiatry & Mental Health Studies Keywords: circadian rhythm; sleep disorders; socioeconomic status; stress; allostatic load; health outcome
Online: 10 December 2018 (14:18:30 CET)
The variations in socioeconomic status (SES) between different social classes of a population correspond to differences in accessibility to all resources available and able to improve global health. While SES is now known as one of the main determinants for a good health and a good aging, its influence on sleep disorders (SD) is not well understood. SES is a concept, not directly observable but estimated using indicators like income, education, occupational status and area of living. This theoretical review explores some theories linking environment of people with occurrence of SD, with different patterns associated to SES. A model of interaction is proposed to summarize and conceptualizes these interactions and to promote more research on the topic.
ARTICLE | doi:10.20944/preprints201808.0457.v1
Subject: Life Sciences, Other Keywords: Sleep, Office workers, office workstation, wellbeing, stress, physical activity, wearables, digital health, sleep quality index, tracking sleep quality, workstation types, accelerometry, heart rate variability
Online: 27 August 2018 (11:33:23 CEST)
Study Objective: This study examined office workstation types’ impact on objective health-related metrics including stress, physical activity (PA), and sleep quality. We propose a sensor-based sleep quality index (SB-SQI) to fill a needed gap for objective sleep quality measurement over short timescales. Methods: We monitored 231 office workers using chest-worn sensors for 72 hours, yielding 11,736 hours of usable data from 163 participants (mean age 43.4, 56% women). SB-SQI was based on a validated algorithm estimating sleep-onset latency, total sleep time, and sleep efficiency, using the scoring method from the Pittsburg Sleep Quality Index (PSQI). We examined the relationships between SB-SQI, office workstation type (open-bench seating, cubicle, and private office), work-hours stress (standard deviation of heart rate variability), and after-work PA (relative duration of moderate-to-vigorous activity). Results: The sensor-derived poor-sleep ratio of the private office workers was higher than with other office workstation types (81% vs. 66.1%, p = 0.023). PSQI revealed a similar but insignificant trend with a lower effect-size. Among good-sleepers, open-bench seating workers had 22% (p = 0.018) less stress during work hours than others. A significant association between work-hours stress and after-work hours PA (r = 0.331, p = 0.000) was observed irrespective of office workstation type, with the highest PA level observed for open-bench seating workers. Conclusions: Office workstation type had a significant impact on work-hours stress, affecting PA after work hours, which influenced sleep quality. SB-SQI could be more sensitive than PSQI in determining the impact of office workstation types on sleep quality.
ARTICLE | doi:10.20944/preprints202208.0507.v1
Subject: Behavioral Sciences, Clinical Psychology Keywords: sleep education; insomnia; training; circadian rhythms; behavioral sleep medicine, psychotherapy; dissemination; implementation science; mental health
Online: 30 August 2022 (05:07:56 CEST)
Despite the strong links between sleep, circadian rhythms, and mental health, sleep education has been neglected in mental healthcare provider training programs. The current pilot study examined the potential efficacy and acceptability of a sleep education workshop for trainee psychologists, called the Sleep Psychology Workshop. Eleven students completing their Master of Psychology degrees (90% female, 24.4 ± 1.6 years old) attended the Sleep Psychology Workshop as part of their Health Psychology course, delivered as three, two-hour lectures (total six hours). Trainees’ sleep psychology knowledge quiz scores (% correct) demonstrated significant improvement from pre- (M = 60%, SD = .09) to post-workshop (M = 79%, SD = .08), t (6) = -5.18, p = .002. Trainees also reported increased self-efficacy to use common sleep-related assessment instruments and empirically supported interventions to manage sleep and circadian rhythm disturbances, along with increased confidence to manage insomnia disorder in clinical practice (all p<.02). Trainees also endorsed the workshop as an acceptable sleep education program for trainee psychologists via a post-workshop feedback survey, focus group, and six-month follow-up survey. This pilot study provides preliminary evidence for the Sleep Psychology Workshop as an effective and acceptable sleep education program for trainee psychologists.
ARTICLE | doi:10.20944/preprints202106.0569.v1
Subject: Medicine & Pharmacology, Dentistry Keywords: Sleep quality; Chronic pain; Temporomandibular disorder; Pittsburgh Sleep Quality Index; STOP-Bang; Epworth Sleepiness Scale
Online: 23 June 2021 (11:11:14 CEST)
Objectives: This study aimed to investigate and compare sleep quality between patients with chronic temporomandibular disorder and healthy controls, and to analyze the association of sleep quality with disease characteristics, obstructive sleep apnea risk factors, and excessive daytime sleepiness. Methods: Chronic temporomandibular disorder patients (n=503) and 180 age- and sex-matched healthy controls were included, who completed well-organized clinical report and answered questions on sleep quality (Pittsburgh Sleep Quality Index), sleep apnea risk factors (STOP-Bang questionnaire), and excessive daytime sleepiness (Epworth sleepiness scale). Results: Mean global Pittsburgh Sleep Quality Index scores were significantly higher in the patients (6.25±2.77) than in healthy controls (6.25±2.77) (p<0.001). Poor sleep was significantly more prevalent in the patient group (56.9%) than in healthy controls (22.2%) (p<0.001). Compared with healthy controls, chronic temporomandibular disorder patients had a higher likelihood of obstructive sleep apnea. (STOP-Bang total score ≥3; 7.2% vs. 16.1%; p<0.01) and higher excessive daytime sleepiness (Epworth sleepiness scale score ≥10; 12.8% vs. 19.7%; p<0.05). Age (odds ratio=2.551; p<0.001), female sex (odds ratio=1.885; p=0.007), total Epworth sleepiness scale score (odds ratio=1.839; p=0.014), and headache attributed to temporomandibular disorder (odds ratio=1.519; p=0.049) were the most powerful predictors of poor sleep (global Pittsburgh Sleep Quality Index score ≥5) in chronic temporomandibular disorder patients. Conclusion: Chronic temporomandibular disorder patients had sleep quality impairment. Various factors, including peripheral and central factors, affect the patient's sleep quality. Therefore, in addition to sleep quality and sleep-related problems, the underlying central mechanism for poor sleep quality should be assessed when treating chronic temporomandibular disorder patients.
REVIEW | doi:10.20944/preprints202211.0186.v2
Subject: Medicine & Pharmacology, Clinical Neurology Keywords: Sleep deprivation; Cytokines; curcumin; nano – curcumin
Online: 11 November 2022 (02:06:44 CET)
In this review, the following information describes the manifestation of sleep deprivation by human beings and its adverse effect on their health. Sleep deprivation has been demonstrated into namely two types known as REM sleep and NREM sleep affecting our health in so a problematic way that it is making our body immune to many diseases leading to lethal problems. Therefore, great research by many scientists has discovered that the turmeric “Curcuma longa” which is been used in every Indian kitchen since ancient times, has shown a remarkable effect on the problem caused by sleep deprivation but due to its poor solubility and low bioavailability drawn it into a great disadvantage. But the help of the study of nanotechnology and the evolution of curcumin into nano–curcumin made the possibility of the remarkable effect by making the curcumin more potent and enhancing its stability. Immunological changes due to sleep deprivation lead to Alzheimer’s disease, glioma, neuropathic pains, and many more. Therefore, this review has been summarized as it is been providing information related to curcumin and its affection for sleep deprivation.
ARTICLE | doi:10.20944/preprints202205.0075.v1
Subject: Behavioral Sciences, Behavioral Neuroscience Keywords: nap; sleep; motor adaptation; learning; consolidation
Online: 6 May 2022 (10:36:15 CEST)
Daytime napping offers benefits for motor memory learning and is used as habitual countermeasure to improve daytime functioning. A single napping is shown to ameliorate motor memory learning, although the effect of consecutive napping on motor memory consolidation remains unclear. This study aimed to explore the effect of daytime napping over multiple days on motor memory learning. Twenty university students were divided into the napping group and no-nap (awake) group. Napping group performed motor adaption tasks before and after napping for three consecutive days, whereas no-nap group performed the task on the similar time schedule as the napping group. In addition, a subsequent retest was conducted one week after the end of the intervention. The speed to complete the task of the napping group was significantly shorter than that of the awake group in the retention test. No significant difference was confirmed for trajectory length to complete the task. Thus, consecutive napping may facilitate motor learning and motor memory consolidation in the long term.
REVIEW | doi:10.20944/preprints201912.0333.v1
Subject: Keywords: memory; p75NTR; synaptic plasticity; sleep deprivation
Online: 25 December 2019 (03:27:36 CET)
In recent years, many molecular and environmental factors have been studied to understand how synaptic plasticity is modulated. Sleep, as an evolutionary conserved biological function, has shown to be a critical player for the consolidation and filtering of synaptic circuitry underlying memory traces. Although sleep disturbances do not alter normal memory consolidation, they may reflect fundamental circuit malfunctions that can play a significant role in exacerbating diseases, such as autism and Alzheimer’s disease. Very recently, scientists sought to answer part of this enigma and they identified p75 neurotrophic receptor (p75NTR) as a critical player in mediating impairments in hippocampal-dependent associative plasticity upon sleep deprivation. This paper will review the role of the p75NTR, critically discuss the impact and implications of this research as the bridge for sleep research and neurological diseases.
ARTICLE | doi:10.20944/preprints202007.0327.v1
Subject: Medicine & Pharmacology, General Medical Research Keywords: Obstructive sleep apnea; Metabolomics; Triglycerides; Phosphocholines; Ceramides; Apnea Hypopnea Index; Polysomnography; Lipid metabolism; Multilevel Sleep Surgery
Online: 15 July 2020 (09:19:05 CEST)
Background: Obstructive sleep apnea (OSA) is caused by partial or complete obstruction of the upper airways. Corrective surgeries aim at removing obstructions in the nasopharynx, oropharynx, and hypopharynx. OSA is associated with increased risk of various metabolic diseases. Our objective was to evaluate the effect of surgery on the plasma metabolome. Methods: This study included 39 OSA patients who underwent Multilevel Sleep Surgery (MLS). Clinical and anthropometric measures were taken at baseline and 5 months after surgery. Results: The mean Apnea Hypopnea Index (AHI) significantly dropped from 22.0 ± 18.5 events/hour to 8.97 ± 9.57 events/hour (p-Value <0.001). The Epworth’s sleepiness Score (ESS) dropped from 12.8 ± 6.23 to 2.95 ± 2.40 (p-Value <0.001) indicating success of the surgery in treating OSA. Plasma levels of metabolites, phosphocholines (PC) PC.41.5, PC.42.3, ceremide (Cer) Cer.44.0, and triglyceride (TG) TG.53.6, TG.55.6 and TG.56.8 were decreased (p-Value<0.05) whereas lysophosphatidylcholines (LPC) 20.0 and PC.39.3 were increased (p-Value<0.05) after surgery. Conclusion: This study highlights the success of MLS in treating OSA. Treatment of OSA resulted in improvement in metabolic status that was characterized by decreased TG, PCs and Cer metabolites post-surgery indicating that the success of the surgery positively impacted the metabolic status of these patients.
ARTICLE | doi:10.20944/preprints202204.0121.v1
Subject: Medicine & Pharmacology, Psychiatry & Mental Health Studies Keywords: cancer; insomnia; sleep; circadian; the DBST index
Online: 13 April 2022 (08:36:14 CEST)
Patients with cancer experience insomnia or sleep disturbances. This study aimed to explore whether the discrepancy between a patient's desired time in bed and total sleep time (DBST) index is a measurement tool for insomnia severity or sleep onset latency [SOL] in patients with cancer. This retrospective medical records review study gathered clinical information and rating scale scores including Insomnia Severity Scale (ISI), Cancer-related Dysfunctional Beliefs about Sleep scale (C-DBS), Patient Health Questionnaire-9 items (PHQ-9), State subcategory of State and Trait Anxiety Inventory, and Short form of Fear of Progression Questionnaire. Sleep indices of time variables (bedtime, sleep onset time, and wake-up time), duration variables [SOL, time in bed (TIB), time in bed for 24 hours (TIB/d), and duration from wake-up time to bedtime (WTB)], and the DBST index were calculated. The ISI score was predicted by PHQ-9 (β=0.34, P<0.001), C-DBS (β=0.17, P=0.034), and DBST index (β=0.22, P=0.004) with a significant correlation with the DBST index (r=0.19, p=0.020). The DBST index was significantly correlated with long SOL (r=0.23, P=0.005). Long SOL was predicted by early bedtime (β=0.18, P=0.045), short WTB (β=-0.26, P=0.004), and high DBST index (β=0.19, P=0.013). The DBST index was significantly correlated with a predicting variable each for insomnia severity and SOL in patients with cancer.
ARTICLE | doi:10.20944/preprints202105.0181.v1
Subject: Behavioral Sciences, Applied Psychology Keywords: physical activity; sleep; inhibitory performance; mediating effects
Online: 10 May 2021 (11:51:54 CEST)
The current study aimed to investigate the relationship between physical activity (PA) level and inhibitory control performance and then determine whether this association was mediated by multiple sleep parameters (i.e., subjective sleep quality, sleep duration, sleep efficiency, sleep disturbance). Methods. 180 healthy university students (age: 20.15 ± 1.92 years) from the East China Normal University were recruited in the present study. PA level, sleep parameters, and inhibitory control performance were assessed using the International Physical Activity Questionnaire (IPAQ), the Pittsburgh Sleep Quality Index Scale (PSQI), and a Stroop test, respectively. Data were analyzed using structual equation modeling. Results. A higher level of PA was linked to better cognitive performance. Furthermore, higher subjective sleep quality and sleep efficiency were associated with better inhibitory control performance. The mediation analysis revealed that subjective sleep quality and sleep efficiency mediated the relationship between PA level and inhibitory control performance. Conclusion. Our results are in accordance with the literature and buttress the idea that a healthy lifestyle that involves a relatively high level of regular PA and adequate sleep patterns is beneficial for cognition (e.g., inhibitory control performance). Furthermore, our study adds to the literature that sleep quality and sleep efficiency mediates the relationship of PA and inhibitory control performance expanding our knowledge in the field of exercise-cognition.
ARTICLE | doi:10.20944/preprints202103.0136.v1
Subject: Medicine & Pharmacology, Allergology Keywords: Sleep apnea; hypoxemia; cognitive; brain health; MRI
Online: 3 March 2021 (14:14:41 CET)
We aim to determine the sleep correlates of age-related brain loss in a sample of middle-aged to older males with obstructive sleep apnea. We evaluated consecutive treatment naïve male patients with OSA (AHI≥15 events/hr) without dementia, stroke or heart disease, from January to November of 2019. We collected demographic variables, vascular risk factors, and sleep questionnaires. We also obtained computerized neurocognitive testing with the Go-No-Go Response Inhibition Test, Stroop Interference Test, Catch Game Test, Staged Information Processing Speed Test, Verbal Memory Test and Non-Verbal Memory Test. We derived age and education adjusted domain-specific Z-scores for global cognition, memory, attention, processing speed and executive function. We used brain MRI T1-weighted images to derive total hippocampal and gray matter volumes. Partial correlations evaluated associations between the ISI, AHI, and oxygen level during sleep, with cognitive domains and brain volumes. Sixteen participants, age 40-76 years, 73% Hispanic/Latino, with mean AHI=48.9±25.5 and mean oxygen saturation of 91.4±6.9% during sleep. Hypertension was seen in 66% and diabetes in 27%. We observed that ISI and oxygen level during sleep had strong correlations with brain volumes and cognition. These preliminary findings may aid in developing future strategies to improve age-related brain loss in OSA.
REVIEW | doi:10.20944/preprints202101.0446.v1
Subject: Life Sciences, Biochemistry Keywords: Diuretic hormone; behavior; sleep; feeding; neuromodulation; neurohormone
Online: 22 January 2021 (12:48:25 CET)
Leucokinins (LKs) constitute a neuropeptide family first discovered in a cockroach and later identified in numerous insects and several other invertebrates. The LK receptors are only distantly related to other known receptors. Among insects, there are many examples of species where genes encoding LKs and their receptors are absent. Furthermore, genomics has revealed that LK signaling is lacking in several of the invertebrate phyla and in vertebrates. In insects, the number and complexity of LK expressing neurons vary, from the simple pattern in the larva of Drosophila where the entire CNS has 20 neurons of three main types, to cockroaches with about 250 of many different types. Common to all studied insects is the presence or 1-3 pairs of LK-expressing neurosecretory cells in each abdominal neuromere of the ventral nerve cord, that, at least in some insects, regulate secretion in Malpighian tubules. This review summarizes the diverse functional roles of LK signaling in insects, as well as other arthropods and mollusks. These functions include regulation of ion and water homeostasis, feeding, sleep-metabolism interactions, state-dependent memory formation, as well as modulation of gustatory sensitivity and nociception. Other functions are implied by the neuronal distribution of LK, but remain to be investigated.
ARTICLE | doi:10.20944/preprints202011.0598.v1
Subject: Keywords: caffeine; sleep habits; lifestyle; medical students; universities
Online: 23 November 2020 (20:15:40 CET)
Objectives: To determine the effects of caffeine consumption on the sleep habits and lifestyle of medical students. Methods: A cross-sectional study was conducted at Jinnah Sindh Medical University (JSMU) and Hamdard College of Medicine. On 422 undergraduate students aged 18-25 years, through random sampling. The duration of the study was from January 2019 to June 2019. The data was collected through self-administered questionnaire which included data regarding sleep habits and lifestyle of medical students. Results: Majority (81.6%) of the students consumed caffeine while only (18.4%) did not. One third of the participants (31.8%) reported caffeine consumption increased their academic performance and (57.3%) reported that it does not. More than half of the participants (63.3%) who consumed caffeine slept during class, whereas (47.2%) never had difficulty in falling asleep during the night. Conclusion: This research concluded that caffeine does have some role on sleep habits of medical students as they tend to have less sleep hours, experience day time dysfunction, average quality of sleep, and falling asleep during class. It has been concluded that caffeine has no effect on eating habits of medical students however, it does increase the screening time, keeping them active.
ARTICLE | doi:10.20944/preprints201812.0224.v1
Subject: Medicine & Pharmacology, Nutrition Keywords: self-esteem; quality of sleep; eating; nursing
Online: 18 December 2018 (12:12:23 CET)
In recent decades, organizational research has given special attention to the mechanisms promoting the health and wellbeing of nursing professionals. In this context, self-esteem is a personal resource which influences wellbeing at work and psychological wellbeing of nurses. The purpose of this study was to analyze the mediating role of eating in the effect of sleep quality on self-esteem in nursing professionals. The sample of 1073 nurses were administered the Rosenberg General Self-Esteem Scale, the Pittsburgh Sleep Quality Index and the Three-Factor Eating Questionnaire-R18. The results show that poor sleep quality and type of eating directly and indirectly affect self-esteem. More so, poor sleep quality deteriorated self-esteem through emotional eating, and even though emotional eating facilitated disinhibited eating, this relationship had no significant effects on self-esteem. The findings of this study suggest that hospital management should implement employee health awareness programs on the importance of healthy sleep and design educational interventions for improving the quality of their diet.
ARTICLE | doi:10.20944/preprints202302.0425.v1
Subject: Medicine & Pharmacology, Other Keywords: sleep apnea; hypoxia; gout; hyperuricemia; urate; metabolic comorbidities
Online: 24 February 2023 (09:31:14 CET)
Gout is not only associated with obstructive sleep apnea (OSA), but the intermittent episodes of hypoxia that occur with OSA may also have a role in causing gout. Epidemiological studies have documented a higher incidence and prevalence of gout in individuals diagnosed with OSA than in individuals never diagnosed with OSA. The pathophysiology of OSA’s chronic episodes of hypoxia leading to hyperuricemia and gout involves boththe overproduction and underexcretion of uric acid. Treating OSA may be an additional way to control gout and its life-threatening comorbidities. Clinicians are urged to evaluate their patients with hyperuricemia/gout for OSA as it may lead to alternative ways to control gout with superior outcomes that simply pharmacologic treatment alone.
ARTICLE | doi:10.20944/preprints202302.0155.v1
Subject: Behavioral Sciences, Behavioral Neuroscience Keywords: Sleep; Substance Use; Insomnia; Anxiety; Depression; Students; Stress
Online: 9 February 2023 (06:03:39 CET)
This study examined the prevalence of illegal drug use in UK students and motivators behind such behaviour. Additionally, we explored possible relationships between substance use, psychosocial motivators, and psychiatric distress. N=543 students completed online measures of substance use, anxiety, depression, perceived stress, insomnia. A series of reasons behind their use were ranked based on importance. Reported cannabis, cocaine, nitrous oxide, ketamine and MDMA use were most prevalent based on lifetime, past year, and month assessments. The experience of anxiety, depression, perceived stress, and insomnia were related to increased reports of substance use. Poor self-confidence and self-medication were key motivators of illicit drug use in those presenting greater psychiatric distress. These outcomes add to the sparse body of literature concerning illicit substance use in relation to psychiatric distress amongst UK students. Furthermore, we provided novel insight into the psychosocial motivators of such use.
ARTICLE | doi:10.20944/preprints202209.0383.v1
Subject: Medicine & Pharmacology, General Medical Research Keywords: Obstructive Sleep Apnea; COVID-19; Hospitalization; Infection; Epidemiology
Online: 26 September 2022 (08:02:12 CEST)
Background: Medical comorbidities increase the risk of severe COVID-19 infection. In some studies, obstructive sleep apnea (OSA) has been identified as a comorbid condition that is associated with an increased prevalence of COVID-19 infection and hospitalization, but few have investigated this association in a general population. Research Question: In a general population, is OSA associated with increased odds of COVID-19 infection and hospitalization and are these altered with COVID-19 vaccination? Study Design: Cross-sectional survey of a diverse sample of 15,057 U.S. adults Results: COVID-19 infection and hospitalization rates were 38.9% and 2.9% respectively. OSA or OSA symptoms were reported in 19.4%. In logistic regression models adjusted for demographic, socio-economic and comorbid medical conditions, OSA was positively associated with COVID-19 infection (aOR: 1.58, 95%CI: 1.39-1.79) and COVID-19 hospitalization (aOR: 1.55, 95% CI: 1.17-2.05). In fully adjusted models, boosted vaccination status was protective against both infection and hospitalization. Boosted vaccination status attenuated the association between OSA and COVID-19 related hospitalization, but not infection. Participants with untreated or symptomatic OSA were at greater risk for COVID-19 infection; those with untreated, but not symptomatic OSA were more likely to be hospitalized. Interpretation: In a general population sample, OSA is associated with a greater likelihood of having had a COVID-19 infection and a COVID-19 hospitalization with the greatest impact observed among persons experiencing OSA symptoms or who were untreated for their OSA. Boosted vaccination status attenuated the association between OSA and COVID-19 related hospitalization.
ARTICLE | doi:10.20944/preprints202103.0323.v1
Subject: Medicine & Pharmacology, Allergology Keywords: cardiorespiratory fitness; VO2 peak; sleep quality, physical activity
Online: 11 March 2021 (16:04:34 CET)
Abstract: Background: Recently, cardiorespiratory fitness (CRF) has been postulated as an adverse health outcome related to poor sleep quality. However, studies investigating the relationship between CRF with subjective sleep quality index are scarce. Thus, the current study aimed to investigate the association between CRF and Pittsburgh sleep quality index (PSQI) in apparently healthy people. The secondary aim was to investigate the association between reported physical activities (PA) and PSQI. Methods: 33 apparently healthy male participants volunteered to participate. CRF (VO2 peak) was measured via cardiopulmonary exercise testing on a treadmill. A short form of the International physical activity questionnaire (IPAQ) was used to measure PA, and PSQI was used for sleep quality index. Results: There was no correlation between CRF and PSQI total score or any component of the PSQI. Also, there was no correlation between IPAQ and PSQI total score. Categorical data analysis of the two questionnaires revealed that 45.5% of the participants reported low physical activity and poor sleep quality. Conclusions: There was no association between CRF, reported PA with subjective sleep quality index. The use of objective tools for assessing the quality and quantity of sleep should be recommended for future studies as it may clarify the association between CRF and sleep quality.
ARTICLE | doi:10.20944/preprints202002.0046.v1
Subject: Life Sciences, Biotechnology Keywords: wearables; biosensors; sleep; fitbit; oura; hexoskin; withings; cognition
Online: 4 February 2020 (10:49:44 CET)
Sleep quality has been directly linked to cognitive function, quality of life, and a variety of serious diseases across many clinical domains such as psychiatry and cardiology. Standard methods for assessing sleep involve overnight studies in hospital settings, which are uncomfortable, expensive, not representative of real sleep, and difficult to conduct on a large scale. Recently, a number of commercial digital devices have been developed that record physiological data which can act as a proxy for sleep quality in lieu of standard electroencephalogram recording equipment. Each device company makes different claims of accuracy and measures different features of sleep quality, and it is still unknown how well these devices correlate with one another and perform in a research setting. In this pilot study of 21 participants, we investigated whether outputs from four sensors, specifically FitBit, Withings Aura, Hexoskin, and Oura Ring, were related to known cognitive and psychological metrics, including the PSQI and N-back test. We found that sleep metrics extracted from these devices did not predict cognitive and psychological metrics well in our pilot data. However, we did identify certain signification associations, specifically the Oura Ring’s total sleep duration and efficiency in relation to the PSQI measure with p=0.004 and p=0.033, respectively. Additionally, correlation of various sleep features among the devices across the sleep cycle was almost uniformly low. These findings can hopefully be used to guide future sensor-based sleep research.
ARTICLE | doi:10.20944/preprints201810.0579.v1
Subject: Behavioral Sciences, Social Psychology Keywords: Problematic Internet use, sleep disturbance, sex difference, adolescents
Online: 24 October 2018 (14:15:09 CEST)
The Internet use has become an integral part of daily life, adolescents are especially at a higher risk to develop problematic Internet use (PIU). Although one of the most well-known comorbid conditions of PIU is sleep disturbance, little is known about the sex disparity in this association. This school-based survey in students of grades 7-9 was conducted to estimate the prevalence of PIU and sleep disturbance among Chinese adolescents, to test the association between PIU and sleep disturbance, and to investigate the role of the child’s sex in this association. A two-stage stratified cluster sampling method was used to recruit participants, and a two-level logistic regression models were fitted. The mean Internet addiction test scores was 37.2 (SD: 13.2), and 15.5% (736) met the criteria for PIU. After adjusting for control variables, problematic Internet users were at a higher risk of sleep disturbance (adjusted odds ratio=2.41, 95% CI=2.07-3.19). Sex-stratified analyses also demonstrated that association was greater in girls than boys. In this respect, paying more attention to the sleep patterns of adolescents who report excessive Internet use is recommended, and this early identification may be of practical importance for schools, parents, and adolescents themselves.
ARTICLE | doi:10.20944/preprints202303.0198.v1
Subject: Medicine & Pharmacology, Pediatrics Keywords: Covid-19 lockdown; sleep quality; parental education; SENDO project
Online: 10 March 2023 (13:36:42 CET)
Abstract: Introduction: Covid-19 lockdown has caused important changes in children's routines, especially in terms of nutrition, physical activity, screen time, social activity, and school time. Regarding these changes, recent studies show that Covid-19 lockdown was associated with higher levels of anxiety and depression in children. The objective of this study was to assess changes in sleep quality in Spanish children during lockdown decreed by the Spanish government between March and June 2020. Methodology: We compared the BEAR score of 478 participants in the SENDO project at the periods before, during and after lockdown. We used hierarchical models with two levels of clustering to account for the intra-cluster correlation between siblings. Interaction of time with and a set of a priori selected variables was assessed by introducing the interaction term into the model and calculating the likelihood ratio test. Results: Mean scores in the BEAR questionnaire referred to the periods before, during, and after lockdown were 0.52 (sd 1.25), 1.43 (sd 1.99) and 1.07 (sd 1.55), respectively, showing a worsening of sleep quality as a result of confinement. Parental level of education was found to be an effect modifier (p for interaction=0.004). Children whose parents had higher education (university graduates or higher) showed a smaller worsening than those without. Conclusion: We found that the mean score in the BEAR questionnaire significantly worsened during lockdown and significantly improved after it. However, it did not reach the initial level. The mean score in the BEAR questionnaire referred to the period after lockdown was significantly higher than before.
Subject: Life Sciences, Other Keywords: deep sleep; slow-wave activity; evolution; comparative; physiology; homeostasis
Online: 2 August 2022 (04:46:33 CEST)
A modern definition of “deep sleep” is elusive despite being ubiquitously appreciated as an important physiological state supporting health and homeostasis. In modern times, human deep sleep is identified by specific bioelectric signatures in the electroencephalogram (EEG) emerging somewhere between periods of wakefulness. However, deep sleep has been used to describe states of quiescence well before the first electrical brain recordings in the late 1800s, highlighting its own evolution in both lay and medical literature. Furthermore, EEG states are not only ill-defined in most mammals outside of humans and laboratory rodents, but non-existent in some invertebrates. Given that all organisms rest and do so with seemingly well-defined utility, it remains a challenge linguistically, scientifically, and comparatively define what “deep sleep” means—or what it should—in a research context. Here, I explore standard definitions of deep sleep from a modern, comparative perspective, and discuss potential problems of using a strict and narrow definition of such a fleeting concept that has historically undergone significant updates. Finally, I suggest a path towards resolving inconsistencies around the meaning of “deep sleep” and consider whether it is truly reflected by any one measure.
ARTICLE | doi:10.20944/preprints202207.0454.v1
Subject: Medicine & Pharmacology, Dentistry Keywords: orthodontics; airway; clear aligners; 3D diagnostics; sleep apnea; CBCT
Online: 29 July 2022 (09:37:56 CEST)
This retrospective study evaluated changes in the pharyngeal portion of the upper airway in pa-tients with constricted and normal airway treated with clear aligners (Invisalign, Align). Additionally, the paper has assessed the change of tongue position in the oral cavity from lateral view. Evaluation was performed with specialized software (Invivo 6.0, Anatomage) on pre-treatment and posttreatment pairs of cone beam computed tomography imaging (CBCT) data. The level of airway constriction, volume, cross-section minimal area, and tongue profile were evaluated. Patients with malocclusion, with pair or initial and finishing CBCT and without sig-nificant weight change between the scans, treated with Invisalign clear aligners were distributed in two groups. Group A consisted of fifty-five patients with orthodontic malocclusion and con-stricted upper airway. Control group B consisted of thirty-one patients with orthodontic malocclusions without any airway constriction. In the group with airway constriction, there was a statistically significant increase in volume during therapy (p<0.001). The surface of the most con-stricted cross-section of airway did not change significantly after treatment in any of the groups. The airway constriction was most frequently localized at the level of 2nd cervical vertebra. The final tongue position was different from initial in 62.2% of all clear aligner treatments.
REVIEW | doi:10.20944/preprints202003.0427.v1
Subject: Keywords: COVID19; natural immune boosters; vitamins; fruits and vegetables; sleep
Online: 29 March 2020 (08:26:36 CEST)
The coronavirus COVID-19 epidemic has wreaked havoc on inhabitants of earth killing thousands of humans from more than 150 countries. The epidemic has put a number of countries under complete lockdown and the deadly situation is still prevailing around the globe. Vaccines have been long known as the most effective means of preventing viral infections. However, the lack of vaccines against COVID-19 has further worsened the situation. In this time of health crisis, it is the duty of scientific research community to provide alternative, effective and affordable strategies to vaccinate human bodies against viral infections-COVID-19 based on focused experimental approaches. Growing evidence suggests that certain natural foods and lifestyle changes have potential to optimize immune functions against viral infections including improving defense function, resistance towards invading pathogens, while maintaining self-tolerance. Boosting immune system gives an edge in fending off viruses and staying healthy. This review presents the six smart steps to add to your to-do list which let the inner work of immunity take place against viral infections-COVID-19 by dissolving the powers of disease and illness. Many of these factors are associated in their functions to improve or properly maintain the immune function such as promoting anti-inflammatory functions, inhibiting pro-inflammatory mediators, modulating cell-mediated immunity, altering the antigen-presenting cellular functions as well as promoting communication between the innate and adaptive immune responses. Thus, a scientific illustration of boosting the immune system by proper sleep, moderate exercise, avoiding stress, utilizing vitamins enriched foods, intake of more water and use of fruits and vegetables will hopefully help the community to deal with the coronavirus by vaccinating the human systems naturally.
ARTICLE | doi:10.20944/preprints201907.0060.v1
Subject: Engineering, Electrical & Electronic Engineering Keywords: IoT; wearable device; machine learning; streaming data; sleep posture
Online: 3 July 2019 (09:55:40 CEST)
Sleep postures monitoring systems in the hospital aim at transforming sensing signals into quantitative data to characterize the sleep behaviors of the patient. However, a home-care sleep posture monitoring system needs to be user friendly. In this paper, we present iSleePost - a user-friendly home-care intelligent sleep posture monitoring system. We address the labor-intensive labeling issue of traditional machine learning approaches in the training phase. Our proposed mobile health (mHealth) system leverages the communications and computation capabilities of mobile phones for provisioning a continuous sleep posture monitoring service. Our experiments show that iSleePost can achieve 90 percent accuracy in recognizing sleep postures. More importantly, iSleePost demonstrates that an easily-wear wrist sensor can accurately quantify sleep postures.
ARTICLE | doi:10.20944/preprints201905.0092.v1
Subject: Biology, Physiology Keywords: sleep-wake timing; circadian clock; entrainment; light; period; phase
Online: 8 May 2019 (11:11:49 CEST)
The Munich ChronoType Questionnaire (MCTQ) has now been available for more than 15 years; its original publication has been cited 1,240 times (Google Scholar, May 2019); its online version, which was available until July 2017, has produced almost 300,000 entries from all over the world (MCTQ database). The MCTQ has gone through several versions, has been translated into 13 languages and has been validated against other more objective measures of daily timing in several independent studies. Besides being used as a method to correlate circadian features of human biology with other factors – ranging from health issues to geographical factors – the MCTQ gave rise to quantifying old wisdoms, like “teenagers are late” and has produced new concepts, like social jetlag. Some like the MCTQ’s simplicity and some view it critically; it is time to have a self-critical view on the MCTQ, to address some misunderstandings and give some definitions about MCTQ-derived chronotype and the concept of social jetlag.
ARTICLE | doi:10.20944/preprints201901.0190.v1
Subject: Biology, Physiology Keywords: Sleep, neuronal excitability, central nervous system, sensitivity, cognitive function
Online: 18 January 2019 (12:23:11 CET)
The function of sleep in mammal and other vertebrates is one of the great mysteries of biology. Many hypotheses have been proposed, but few of these have made even the slightest attempt to explain the essence of sleep - the uncompromising need for reversible unconsciousness. During sleep, epiphenomena - often of a somatic character - occur, but these cannot explain the core function of sleep. One answer could be hidden in the observations made for long periods of time of the function of the central nervous system (CNS). The CNS is faced with conflicting requirements on stability and excitability. A high level of excitability is desirable, and is also a prerequisite for sensitivity and quick reaction times; however, it can also lead to instability and the risk of feedback, with life-threatening epileptic seizures. Activity-dependent negative feedback in neuronal excitability improves stability in the short term, but not to the degree that is required. A hypothesis is presented here demonstrating how calibration of individual neurons - an activity which occurs only during sleep - can establish the balanced and highest possible excitability while also preserving stability in the CNS. One example of a possible mechanism is the observation of slow oscillations in EEGs made on birds and mammals during slow wave sleep. Calibration to a genetically determined level of excitability could take place in individual neurons during the slow oscillation, so that action potentials are generated during the oscillations “up-phase”. This can only take place offline, which explains the need for sleep. The hypothesis can explain phenomena such as the need for unconsciousness during sleep, with the disconnection of sensory stimuli, slow EEG oscillations, the relationship of sleep and epilepsy, age, the effects of sleep on neuronal firing rate and the effects of sleep deprivation and sleep homeostasis. This is with regard primarily to mammals, including humans, but also all other vertebrates.
ARTICLE | doi:10.20944/preprints201901.0162.v2
Subject: Medicine & Pharmacology, General Medical Research Keywords: ankylosing spondylitis; obstructive sleep apnea; population-based cohort study
Online: 17 January 2019 (04:52:29 CET)
Background: The aim of this study was to investigate the risk of obstructive sleep apnea (OSA) among ankylosing spondylitis (AS) patients in a nationwide population. Methods: We conducted a nationwide cohort study between 2003 and 2013 using the Taiwan National Health Insurance Research Database. The AS cohort included 2210 patients who were newly diagnosed between 2003 and 2013. Randomly selected non-AS controls were matched at a 1:4 ratio based on age, sex and index date. The endpoint of OSA was occurrence or the end of 2013. Cumulative incidences, hazard ratios (HRs) and 95% confidence intervals (CIs) were calculated after adjusting for age, gender, comorbidities and co-medications. Multivariate analyses were performed using Cox proportional hazards model. Due to violation of the proportionality assumption, landmark analysis was conducted to explore the risk of OSA during specific follow-up periods. Results: The adjusted HR (aHR) of OSA for the AS group was 2.826 (95% C.I. = 1.727–4.625) compared to the control group. On landmark analysis, aHR was 7.919 (95% C.I. = 3.169–19.792) for AS group 0–24 months from index date, and decreased to 1.816 (95% C.I. = 0.944–3.494) at ≥ 24 months from index date. On subgroup analyses increased risks of OSA in AS group compared to the control group were found for both males and females (aHRs were 4.533 (95% C.I. = 1.441–14.262) and 2.672 (95% C.I. = 1.522–4.692) for females and males, respectively). On age stratified analysis, there was significant risk only for the 40–59 age group with aHR of 3.913 (95% C.I. = 1.890–8.102). Conclusions: A higher risk of developing OSA was found among newly diagnosed AS cohort during the 12-year follow-up period, especially within 2 years after AS index date and in the 40–59 age group.
ARTICLE | doi:10.20944/preprints202205.0127.v1
Subject: Medicine & Pharmacology, Pathology & Pathobiology Keywords: hypertension; obesity; body composition; intra-abdominal fat; sleep apnea; obstructive
Online: 10 May 2022 (04:45:21 CEST)
Background: Elevated fasting plasma glucose and visceral fat area (VFA) is highly prevalent in obese adults. This study investigated the associations between systemic arterial hypertension (SAH) and laboratory, anthropometric, heart rate variability (HRV), and obstructive sleep apnea markers. Methods: Cross-sectional study with 95 obese patients treated at Obesity Treatment and Surgery Center, located in Salvador, BA, Brazil. SAH data were obtained from electronic medical records of patients. To evaluate the association of SAH with the predictor variables, the sample was stratified in Normotense Group (NG) and Hypertensive Group (HG), and laboratory markers, body composition, polysomnography data, and HRV were measured. Results: The average age of the NG was 36.3 ± 10.1 and HG 40.4 ± 10.6 years, 73.7% were women in the NG and 57.9% in HG; 82.4% in HG had insulin resistance. In the multivarious logistics regression model with adjustments age, sex, height, and oxyhemoglobin saturation, SAH was inversely associated with fasting plasma glucose mg/dL (odds ratio [OR] = 0.96; 95% interval confidence [CI] = 0.92 - 0.99) and VFA cm2 (OR = 0.98; 95% CI = 0.97 - 0.99). The area under curve the VFA was 0.728; CI 95% (0.620 - 0.836) and fasting plasma glucose 0.693; CI 95% (0.582 - 0.804). Conclusions: Lower VFA and fasting plasma glucose concentrations were inversely associated with SAH. These results indicate opportunities to improve the outcome in obese patients through counseling and clinical interventions.
ARTICLE | doi:10.20944/preprints201903.0087.v2
Subject: Medicine & Pharmacology, Other Keywords: tissue hypoxia; sleep disordered breathing; primary snoring; molecular tissue oximeter
Online: 16 August 2019 (06:27:46 CEST)
Pulse oximetry is the current standard for detecting drops in arterial blood oxygen saturation (SpO2) associated with obstructive sleep apnea and hypopnea events in polysomnographic (PSG) testing. In cases of hypoxic challenge, such as occurs during apneic events, regulatory mechanisms restrict blood flow to the skin to preferentially maintain SpO2 for more vital organs. As a result, a measure related to skin tissue oxygenation is likely to be more sensitive to inadequate breathing during sleep than pulse oximetry. Energy Conversion Monitoring (ECM) provides a method for measuring skin tissue oxygen-dependent energy conversion and, as such, is promising for more sensitively detecting sleep disordered breathing (SDB) events compared to pulse oximetry. We hypothesized that ECM would detect hypoxia occurring with SDB events associated with drops in SpO2 but also would detect hypoxic challenge occurring with SDB events not associated with drops in SpO2 (hypopneas defined by a drop in nasal pressure occurring in conjunction with an arousal, respiratory-related arousals, and primary snoring). Primary snoring is of particular interest with respect to the potential of ECM because it is statistically associated with co-morbidities of SDB, such as hypertension, but is not considered pathological because of the lack of a proximal measure of pathology occurring with PSG. In this article we review ECM technology and methodology, present preliminary data indicating that it detects hypoxia occurring in the skin during SDB events that is not detected as blood desaturation by pulse oximetry, and make the case that it is a promising tool for identifying pathology occurring at the mild end of the SDB spectrum.
ARTICLE | doi:10.20944/preprints201905.0353.v1
Subject: Keywords: sleep disorders; socioeconomic status; mediator; allostatic load; health; scoping review
Online: 29 May 2019 (14:48:06 CEST)
The variations in socioeconomic status (SES) between different social classes of a population correspond to differences in accessibility to all resources available and able to improve global health. SES can influence global health trajectory for an individual or a community, depending if SES is low or high. Sleep is sensitive to environmental stimuli, as well as living conditions. Plenty of studies linked sleep complaints with mood disorders, allostatic load or circadian disruption; but very few or none investigated deeply what happened earlier to sleep depending of SES. While SES is now known as one of the main determinants for a good health and a good aging, its influence on sleep disorders (SD) is not well understood. SES is a concept, not directly observable but estimated using indicators like income, education, occupational status and area of living. Even if recent evidence suggested that few of SES indicators like occupational status are linked with sleep disturbances, the relation between SES and health in general with sleep as an outcome or a mediator is not well documented. This scoping review synthetized studies which investigated physiological and psychological mechanisms resulting from a low SES and linked them with sleep disturbances as consequences or as mediators. This review also explore a possible role played by sleep in the relation between socioeconomic status and health inequalities.
ARTICLE | doi:10.20944/preprints201905.0317.v1
Subject: Medicine & Pharmacology, Psychiatry & Mental Health Studies Keywords: childhood trauma; stressful life events; sleep patterns; anxiety; depression; adolescence
Online: 27 May 2019 (12:36:54 CEST)
Adolescence is a critical developmental period associated with an increase in stress, the appearance of anxiety and depressive symptoms, and changes in sleep patterns. Even though the disruption of sleep patterns in stress and anxiety and depressive disorders is well known, the independent effects of childhood trauma and stressful life events on sleep patterns are less understood. We tested the independent effects of stress (childhood trauma and stressful life events) while controlling for anxiety and depression on adolescent sleep patterns. Seven hundred fifty-two adolescents completed self-report questionnaires about childhood trauma, stressful life events, anxiety, and depression. Four sleep factors identifying movement during sleep, sleep regularity, sleep disturbances and sleep pressure were extracted in the principal component analysis of sleep questions. Both childhood trauma and recent stressful life events were significantly associated with sleep disturbances before and after controlling for anxiety and depression.
ARTICLE | doi:10.20944/preprints201805.0335.v2
Subject: Life Sciences, Other Keywords: Alzheimer’s Dementia; anaerobic neurotoxicity; inflammation; neuronal apoptosis; Non-REM Sleep
Online: 4 June 2018 (13:16:46 CEST)
Research into the causes of neurotoxicity in Alzheimer’s Dementia (AD) has focused on neurofibrillary tangles and beta amyloid (Aβ) plaques. This paper proposes the heterodox theory that these hallmarks of AD are the visible effects, not direct causes of neuronal necrosis. Rather AD results from a combination of age-induced, disproportional decline in physiological support for aerobic metabolism, and dysregulation of the sleep cycle processes. The hypothesis is that the decimation of neurons in AD results from a combination of neurotoxicity and increased apoptosis caused by: 1. direct damage from toxic waste products of anaerobic glycolysis due to a progressive decline in the capacity of neurons to perform oxidative phosphorylation (OXPHOS) and an increased reliance on anaerobic glycolysis to meet metabolic needs; 2. impaired cellular repair and effluent release due to dysregulation of non-rapid eye movement (NREM) sleep allowing damage to cell membranes and synaptic junctions to accumulate inducing a chronic inflammatory response; 3. indirect damage from products produced by inflammatory reaction to toxic metabolites; 4. neuronal apoptosis from the AβPP-mediated pathway due to the age-induced decline of growth hormone (GH), GH-releasing hormone (GHRH) and insulin-like growth factor (IGF).
ARTICLE | doi:10.20944/preprints201805.0482.v1
Subject: Medicine & Pharmacology, Other Keywords: screen time; sleep duration; body mass index (BMI); time use
Online: 31 May 2018 (16:34:38 CEST)
Today, due to recent developments in technology, children devote plenty of time for screen viewing. However, its harmful effects are not yet clear. The purpose of present study was to examine the associations among screen viewing and sleep duration, and body mass index (BMI) in under-five years old children. This cross-sectional study was conducted with 322 under-five healthy children that were selected using multistage stratified cluster sampling method in 2017. The data that were gathered by time-use diary method were analyzed using Kolmogorov-Smirnov test, Spearman correlation tests, multiple linear regression analysis, one-way ANCOVA, two-way ANCOVA. There was a negative correlation between screen time and sleep duration (rs = -0.42, p = 0.00), positive correlation between screen time and BMI (rs = 0.38, p = 0.00) and sleep duration negatively correlated with BMI (rs = -0.22, p = 0.00). screen viewing was a predictive factor for both sleep duration (β = -0.26, p = 0.00) and BMI (β = -0.26, p = 0.00). screen viewing had a significant impact on sleep duration (4, 314) = 5.02, P = 0.001) and BMI (F (4, 314) = 1.16, P=0.298). Results of this study indicated that screen viewing is related to sleep duration and BMI in under-five children. furthermore, screen time has an impact on sleep duration and BMI scores of children. findings of our study suggest that sleep duration negatively is associated with BMI in under-five-year-old children.
REVIEW | doi:10.20944/preprints201703.0095.v1
Subject: Medicine & Pharmacology, Behavioral Neuroscience Keywords: autism spectrum disorders; fragile X syndrome (FXS); sleep disorder; melatonin
Online: 15 March 2017 (07:40:49 CET)
Fragile X syndrome (FXS) is the most frequent monogenic form of autism spectrum disorder (ASD). Autistic FXS is caused by loss of the fmr1 gene product, the fragile X mental retardation protein (FMRP), triggering physiological and behavioral abnormalities. It is correlated with clock components for behavioral circadian rhythm. Mutation of this gene causes the disturbances in sleep patterns and circadian behavior commonly observed in patients with autistic FXS, accompanied by frequent dysregulation of melatonin synthesis and melatonin-dependent signaling. These changes impair vigilance, learning and memory, and are also linked to autistic behavior including the abnormal anxiety response. However, although several possible causes, symptoms, and clinical features of ASD have been investigated, the correlation between an altered circadian rhythm and autistic FXS has not been extensively studied. Recent works have highlighted the impact of melatonin on the nervous, immune, and metabolic systems. Even though utilization of melatonin for sleep disorder in ASD has been considered in clinical research, further studies should be aimed at its neuroprotective role in ASD during developmental period. In this review, we focus on the regulatory circuits involved in melatonin dysregulation and circadian system disruption in those with autistic FXS. Additionally, we discuss the neuroprotective effect of melatonin intervention. This may improve neuroplasticity and physical capability. We also review the underlying molecular mechanisms, and suggest that melatonin may be a useful novel treatment for autistic FXS, countering the adverse effects of circadian variation.
ARTICLE | doi:10.20944/preprints202212.0102.v1
Subject: Life Sciences, Other Keywords: Physical inactivity; work from home; sleep; Covid-19 and public health.
Online: 6 December 2022 (11:33:34 CET)
To examine the association of sleep quality and work from home with physical inactivity (PI) in leisure time during Covid-19 pandemic. A population-based household survey was conducted in two Bra-zilian municipalities from October to December 2020. Leisure-time physical activity (PA) was self-reported, and individuals who practiced less than 150 minutes of moderate PA or 75 minutes of vigorous PA weekly were classified as PI. Sleep quality was measured using the Pittsburgh Sleep Quality Index (PSQI). WFH was assessed by: "Currently, how is your work routine regarding location? Associations were investigated using logistic regression and directed acyclic graphs (DAG) for the multivariate models. A total of 1,750 adults were interviewed, 69.1% were PI and 51.9% had poor sleep quality. Furthermore, 79.8% were not in WFH. In multivariate analysis, leisure PI was associated with poor sleep quality (OR:1.59: 95% CI: 1.02-2.48), and not being in WFH (OR:1.62: 95% CI: 1.05-2.50). When performing the combined analysis between these two factors, and who were not in WFH were four times more likely to be PI at leisure (OR=4.22;95%CI:2.05-8.65). The results indicate a high prevalence of PI, with poor quality sleep and non-WFH associated with leisure PI. These combined factors exacer-bated the occurrence of PI.
ARTICLE | doi:10.20944/preprints202204.0301.v1
Subject: Biology, Other Keywords: glucose metabolism disorders; circadian clocks; sleep; blood glucose; glycated hemoglobin H1Ac
Online: 29 April 2022 (11:38:26 CEST)
Background: Evidence supports a causal relationship between circadian disturbance and impaired glucose homeostasis. Method: To determine the effect of a nursing educational intervention on improving healthy sleep, a parallel, open-label clinical trial in subjects with Impaired Fasting Glucose (IFG) or Type 2 Diabetes Mellitus (T2DM) and 18 and older was performed. Study variables were sex, age, fasting glucose, glycated hemoglobin A1c (HbA1c), Pittsburgh Sleep Quality Index (PSQI), sleep duration and efficiency, BMI, antidiabetic treatment and diet and physical exercise. An individual informative educational intervention was carried out following a bidirectional feedback method. It was intended to develop skills to improve sleep through 9 simple tips. An analysis of covariance was performed on all the mean centered outcome variables controlling for the respective baseline scores. Results: After the intervention, in the experimental group, PSQI dropped, the duration and quality of sleep increased. Further, a decrease in fasting glucose and in HbA1c levels was observed. Conclusion: The proposed intervention has proven to be effective to improve sleep quality, time, and efficiency and in only 3 months, to achieve a decrease in fasting glucose and HbA1c levels. These findings support the importance of sleep and circadian rhythms education focused on improving in T2DM or IFG.
ARTICLE | doi:10.20944/preprints202108.0079.v1
Subject: Behavioral Sciences, Applied Psychology Keywords: autism; sleep; fetal alcohol spectrum disorders; nightmares; anxiety; executive function; behaviour
Online: 3 August 2021 (13:07:06 CEST)
Children with Fetal Alcohol Spectrum Disorders (FASD) and Autism Spectrum Disorders (ASD) experience significantly higher rates of sleep disturbances than their typically developing peers. Pre-sleep anxiety and waking emotional content is known to affect the content and frequency of nightmares, which can be distressing to children and caregivers. This is the first study to analyse nightmare frequency and content in FASD, and to assess its association with psychometric outcomes. We assessed reports from 277 caregivers of children with ASD (n=61), FASD (n=112), and TD children (n=104) using the Children’s Sleep Habits Questionnaire (CSHQ), the Child Behavior Checklist (CBCL), the Spence Children’s Anxiety Scale (SCAS) and the Behavior Rating Inventory for Executive Functioning (BRIEF). Within the ASD group, 40.3% of caregivers reported their children had nightmares. Within the FASD group, 73.62% of caregivers reported their children had nightmares and within the TD group, 21.36% of caregivers reported their children had nightmares. Correlation analysis revealed significant associations between anxiety and nightmares, maladaptive behaviour and nightmares, and executive functioning and nightmares in the TD and FASD groups, but not ASD group. This paper adds to the emerging body of work supporting the need for sleep interventions as part of clinical practice with regard to children with ASD and FASD. As a relatively niche but important area of study this warrants much needed further research.
ARTICLE | doi:10.20944/preprints202105.0099.v1
Subject: Biology, Physiology Keywords: COVID-19-sleep disorders; brain mechanisms; the blood-brain barrier permeability.
Online: 6 May 2021 (15:09:41 CEST)
Here, we review findings and trends in sleep research in 2020-2021 demonstrating how COVID-19 and sleep disorders can induce the BBB leakage via neuroinflammation, which might contribute to the 'coronasomnia' phenomenon. The new studies suggest that the controlling of sleep hygiene and quality should be incorporated into the rehabilitation of COVID-19 patients. We also discuss perspective strategies for prevention of COVID-19-related BBB disorders. We demonstrate that sleep might be a novel biomarker of the BBB leakage and the analysis of sleep EEG patterns can be a breakthrough non-invasive technology for diagnosis of the COVID-19-caused BBB disruption.
REVIEW | doi:10.20944/preprints202103.0484.v1
Subject: Medicine & Pharmacology, Allergology Keywords: excessive daytime sleepiness; socioeconomic position; sleep; systematic review; sleepiness; health disparities
Online: 18 March 2021 (13:02:59 CET)
Objective: (1) Describe the current literature on the relationship between EDS and SEP and (2) provide recommendations for consideration of SEP in sleep medicine and biomedical research. Methods: Databases Medline/Pubmed, Web of Science, Google scholar and Scopus were screened using PRISMA guidelines and 19 articles were included in the final synthesis. Results: All studies were cross-sectional. Among these studies, 21.05% (n = 4) are focused on children and adolescent and the lasting 88.95% (n = 15) focused on adults and old people. Age ranged between 8 and 17 years old for children/adolescent and ranged from 18 until 102 years old for adults. Main SEP measures presented in these studies were education, income, perceived socioeconomic status and employment. Sample size in these studies varied from N = 90 participants until N = 33865 participants. Overall, a lower educational level, a lower income and full-time employment were associated with EDS. EDS symptoms are prevalent in women, especially those with a low income or no job; and children and adolescents with difficult living conditions or people working part-time reported more sleep disturbances. Conclusions: SEP is already considered as an important determinant for many health outcomes, but if SEP is embedded in experimental design in psychosomatic research, biomedical research and clinical practice as a constant variable regardless of outcome; it will move forward future investigations.
REVIEW | doi:10.20944/preprints202005.0021.v1
Subject: Medicine & Pharmacology, Clinical Neurology Keywords: anti-IgLON5 disease; sleep disorders; tau protein accumulation; immunotherapy; neurodegenerative diseases
Online: 2 May 2020 (16:26:03 CEST)
The objective of this review is to do an overview about the current knowledge of Anti Iglon5 Syndrome, a disease that was first described in 2014. The IgLON proteins are a family of cell adhesion molecules and the presence of antibodies against IgLON5 are crucial for diagnosis of Anti IgLON5 Syndrome. This syndrome has an expanded clinical spectrum that involves prominent sleep disorder, progressive bulbar dysfunction, gait instability with abnormal eye movements reminiscent and cognitive deterioration sometimes associated with chorea. The main neuropathological finding is the neuronal loss with hyperphosphorylated tau (p-Tau) protein accumulation at hypothalamus, brainstem tegmentum, hippocampus, periaqueductal gray matter, medulla oblongata and upper cervical cord. The exact pathogenesis is still unclear and involves a neurodegenerative process and autoimmune response. The early diagnosis is important to avoid unnecessary tests and prevent complications. Important resources for diagnosis are the antibody testing of serum and CSF for IgLON5-IgG. The mortality of anti IgLON5 syndrome is high and new studies published described a good response to immune therapy. However, the response to immune therapy depends of some clinical and analytical characteristic. In addition, future studies are needed to thoroughly study the aspects of pathogenesis and treatment of this important pathological syndrome.
HYPOTHESIS | doi:10.20944/preprints202004.0215.v1
Subject: Medicine & Pharmacology, Behavioral Neuroscience Keywords: endocanabinoid system; sleep deprivation; animal models; psychosis-like symptoms; drug development
Online: 14 April 2020 (06:28:23 CEST)
The interaction between endocannabinoid (eCB) system with in key brain structures such as hippocampus, amygdala and prefrontal cortex and sleep deprivation (SD)-induced psychosis has been less studied. The present hypothesis revolves around the question whether altered chemical dynamics within the eCB system with the resultant impact on cannabinoid receptors in key cortical hubs would impact SD-induced psychosis-like symptoms. Having this investigated research is expected to pave the path towards identifying newer drug targets namely for schizophrenia.
ARTICLE | doi:10.20944/preprints202003.0462.v1
Subject: Medicine & Pharmacology, Nutrition Keywords: iron; blood donation; restless legs syndrome; quality of life; sleep; fatigue
Online: 31 March 2020 (22:32:59 CEST)
Background: Besides anemia, iron deficiency may cause more subtle symptoms including those of the restless legs syndrome (RLS), the chronic fatigue syndrome (CFS) or sleeping disorders. Objective: The aim of this pre-planned secondary analysis was to compare the frequency and severity of symptoms associated with iron deficiency before and after (intravenous or oral) iron supplementation in iron deficient blood donors. Methods/Design: Prospective, randomized, controlled, single centre trial. (ClinicalTrials.gov: NCT01787526). Setting: Tertiary care center in Graz, Austria Participants: 138 female and 38 male whole blood and platelet apheresis donors aged ≥18 and ≤65 years with iron deficiency (ferritin ≤30ng/ml at the time of blood donation). Interventions: Intravenous iron (1 g ferric carboxymaltose, n=86) or oral iron supplementation (10 g iron fumarate, 100 capsules, n=90). Measurements: Clinical symptoms were evaluated by a survey before iron therapy (visit 0, V0) and after 8-12 weeks (visit 1, V1) including questions about symptoms of RLS, CFS, sleeping disorders, quality of life and symptoms like headaches, dyspnoea, dizziness, palpitations, pica and trophic changes of fingernails or hair. Results: We found a significant improvement in the severity of symptoms for RLS, fatigue and sleep quality (p<0.001). Furthermore, a significant decrease of headaches, dyspnoea, dizziness and palpitations was reported (p<0.05). There was no difference between the type of iron supplementation (intravenous versus oral) and clinical outcome data. Conclusion: Iron supplementation in iron deficient blood donors may be an effective strategy to improve symptoms related to iron deficiency and the wellbeing of blood donors.
CASE REPORT | doi:10.20944/preprints202303.0017.v1
Subject: Medicine & Pharmacology, Nursing & Health Studies Keywords: healthy aging; autonomic nervous activities; heart rate variability; sleep status; well-being
Online: 1 March 2023 (09:12:46 CET)
This case report examined the characteristics of body composition, sleep quality, and autonomic nerve activity in active older adults with a younger body age—calculated from age trends in body composition and basal metabolic rate. We selected two cases who had a metabolic age younger than their actual age. They had good sleep quality, low sleep quality scores, no sarco-penia, strong muscle and grip strength, and balanced autonomic nervous system activity. Fur-thermore, they were determined to be much younger than their actual age. They were compared with two other age- and sex-matched cases, who had poor sleep quality, unbalanced autonomic nervous system activity, and had a physical age closer to their actual age. Older adults with more muscle mass and higher basal metabolism were younger than their actual age, had a better sleep status, and a good balance of autonomic nervous activity in the exercise stimulation. They also had lower percentages of body- and visceral fat and higher body water. Meanwhile, the older adults with standard muscle mass and basal metabolic rate had a poor sleep status and no sympathetic hyperactivity in the exercise simulation.
ARTICLE | doi:10.20944/preprints202211.0552.v1
Subject: Life Sciences, Microbiology Keywords: periodontitis; obstructive sleep apnea; oral microbiota; pathogenic microbiota; chronic diseases; MALDI-TOF
Online: 29 November 2022 (13:09:35 CET)
Commonly the periodontitis has been linked to periodontopathogens categorized in Socransky's microbial complexes, however, there is a lack of knowledge regarding “other microorganisms” or "cryptic microorganisms", which are rarely thought of as significant oral pathogens and are neither previously categorized nor connected to illnesses in the oral cavity. This study hypothesized that these cryptic microorganisms could contribute to the modulation of oral microbiota present in health or disease (periodontitis and/or OSA patients). For this purpose, the presence and the correlation among these cultivable cryptic oral microorganisms were identified and their possible role in both conditions was determined. Data from oral samples of individuals with or without periodontitis and with or without OSA were obtained from a previous study. Demographic data, clinical oral characteristics, and genera and species of cultivable cryptic oral microorganisms identified by MALDI-TOF were recorded. The data of 75 participants were analyzed to determine the relative frequencies of cultivable cryptic microorganisms’ genus and species, microbial clusters and correlations tests were performed. According to periodontal condition, Gingivitis - dental biofilm-induced in reduced periodontium and stage III periodontitis were found to have the highest diversity of cryptic microorganism species. Based on the experimental condition these findings showed that there are genera related to disease conditions and others related to healthy conditions, with species that could be related to different chronic diseases being highlighted as comorbidities periodontitis and OSA. The cryptic microorganisms within the oral microbiota of patients with periodontitis and OSA are present as potential pathogens, promoting the development of dysbiotic microbiota, and the occurrence of chronic diseases, which have been previously proposed to be common risk factors for periodontitis and OSA. Understanding the function of possible pathogens in the oral microbiota will take more research.
ARTICLE | doi:10.20944/preprints202108.0472.v1
Subject: Behavioral Sciences, Developmental Psychology Keywords: adolescents; Internet addiction; game addiction; social media addiction; sleep problems; daytime sleepiness
Online: 24 August 2021 (14:07:14 CEST)
This study aims to establish a link between disturbances in the night sleep habitus, quality of sleep, and daytime sleepiness in adolescents with Internet addiction and different types of content consumed. Methods: This is a cross-sectional observational study of a school sample in three large cities in Central Siberia. 4,615 schoolchildren of 12–18 years old were examined. The Russian-language versions of the Chen Internet Addiction Scale, the Game Addiction Scale for Adolescents, and the Social Media Disorder Scale were used to identify Internet addiction. Questions from the Pittsburgh Sleep Quality Index questionnaire were used to assess nighttime sleep. Daytime sleepiness was assessed using the Pediatric Daytime Sleepiness Scale questionnaire. Results: Adolescents with Internet addiction go to bed and wake up late; they are characterized by a decrease in the duration of nighttime sleep, an increase in sleep onset latency, and frequent nighttime awakenings, as well as more pronounced daytime sleepiness. Among the sleep parameters studied, the indicators of daytime sleepiness and night awakening scales have the highest effect size in Internet-addicted adolescents, regardless of the media consumed. Conclusion: Internet-addicted adolescents are characterized by significant disturbances in the quality of nighttime sleep and excessive daytime sleepiness, which requires appropriate psychological correction.
REVIEW | doi:10.20944/preprints202106.0241.v1
Subject: Medicine & Pharmacology, Allergology Keywords: Neurons; Astrocytes; Neurodegeneration; Neurodevelopmental diseases; Memory; Learning; Inflammation; Oxidative Stress; sleep disorders
Online: 9 June 2021 (07:36:28 CEST)
Inside Central Nervous System (CNS) appears neurons and glia cells. There are more glial cells than neurons and have more functions than neurons. Glia name represents different kind of cells, ones from neural origin (astrocytes, radial glia, and oligodendroglia), and others from blood monocytes (microglia). During ontogeny, neurons appear first (rat fetal 15th) and after astrocytes (rat fetal 21th) indicating a bigger importance function in the CNS. Also, during the phylogeny, reptiles have less astrocytes compared to neurons and in humans, astrocytes are double in number than neurons. This data, perhaps means that astrocytes are more special cells and work in memory and learning? Astrocytes have an important role in different mechanisms protecting CNS across the production of antioxidant and anti-inflammatory proteins, cleaning extracellular medium and helping neurons to communicate with each other correctly. Inflammatory mediators production are important to prevent changes in normal physiology. But, excessive or continue production leads to many diseases, such as Alzheimer's disease (AD), Sclerosis Lateral Amyotrophic (ELA), Multiple sclerosis (MS), and neurodevelopment diseases, like Bipolar disorder, Schizophrenia, and Autism's symptomatology. Different drugs and thecniques can reverse oxidative stress and/or inflammatory excess. This review is intended to serve as an approximation to the field.
ARTICLE | doi:10.20944/preprints202008.0041.v1
Subject: Medicine & Pharmacology, Nutrition Keywords: COVID-19; Lockdown; endocrine diseases; daily habits; food consumption; sleep disorders; anxiety
Online: 2 August 2020 (15:32:38 CEST)
In March 2020 the World Health Organization declared the “pandemic state” due to COVID-19 imposing strict confinement of the world population. People were forced to spend more time at home, changing some daily routines, including social interactions, the possibility to perform sports, and diet habits. These changes could exert a greater impact on patients suffering from chronic diseases, such as endocrine patients. This study aimed to assess the effects of Covid-19 induced quarantine on daily habits in a group of patients with endocrine disorders, focusing on food consumption, eating, and sleep habits during the confinement. Eighty-five endocrine patients were enrolled. A structured interview was administered investigating: socio-demographic information, general medical conditions and habits adopted during the quarantine. All patients underwent the Spielberger State Anxiety Inventory (STAI-Y1) to assess state anxiety. Subjects had mainly a sedentary lifestyle. We found a significant increase in the number of cigarettes in smokers, an increase of meals consumed during the confinement and a high rate of sleep disorder occurrence, especially insomnia. The changes of daily habits were, probably, due to the alterations of routine, that determined more bore and inactivity during the day.
REVIEW | doi:10.20944/preprints201905.0040.v1
Subject: Life Sciences, Other Keywords: breast cancer; sleep; IL-6; hypocretin/orexin; leptin; EEG; autonomic nervous system
Online: 6 May 2019 (08:52:31 CEST)
Sleep is essential for health. Indeed, poor sleep is consistently linked to the development of systemic disease, including depression, metabolic syndrome, and cognitive impairments. Further evidence has accumulated suggesting a role for sleep in cancer initiation and progression (primarily breast cancer). Indeed, patients with cancer and cancer survivors frequently experience poor sleep, manifested as insomnia, circadian misalignment, hypersomnia, somnolence syndrome, hot flushes, and nightmares. These problems are associated with a reduction in patients’ quality of life and increased mortality. Due to the heterogeneity among cancers, treatment regimens, patient populations, and lifestyle factors, the etiology of cancer-induced sleep disruption is largely unknown. Here, we discuss recent advances in understanding the pathways linking cancer and the brain and how this leads to altered sleep patterns. We describe a conceptual framework where tumors disrupt normal homeostatic processes, resulting in aberrant changes in physiology and behavior that are detrimental to health. Finally, we discuss how this knowledge can be leveraged to develop novel therapeutic approaches for cancer-associated sleep disruption, with special emphasis on host-tumor interactions.
REVIEW | doi:10.20944/preprints201810.0641.v1
Subject: Medicine & Pharmacology, Psychiatry & Mental Health Studies Keywords: sleep, socioeconomic status, stress, circadian rhythm, allostatic load, mood disorder, social class
Online: 26 October 2018 (16:32:56 CEST)
Sleep disorders (SD) have a complex aetiology, and socioeconomic status (SES) as determined by social class, household income, ethnicity and education plays an important role in their development. As SD are associated with cognitive impairment and mood disorders, they in turn impact SES. Socioeconomic status also influences allostatic load caused by chronic accumulation of stress throughout life. Environmental and psychological stressors have a direct effect on SD, and they are modulated by SES, in combination with comorbidities like obesity and cardiovascular disease. This review explores the recent theories about the influence of SES on the development of SD in the general population, whether or not occurring with comorbidities, and also focusses on the interplay between socioeconomic status, circadian rhythms, aging and clinical outcomes like metabolic diseases and cancer.
ARTICLE | doi:10.20944/preprints202209.0084.v2
Subject: Medicine & Pharmacology, Pediatrics Keywords: long COVID; Post COVID-19 condition; sleep disorders, SARS-CoV-2; Coronavirus; children
Online: 14 October 2022 (10:13:22 CEST)
Acute SARS-CoV-2 infections in children and adolescents are usually mild. However, they can suffer from ongoing symptoms generally referred as long COVID. Sleep disorders are one of the most frequent complaints in long COVID although precise data are missing. We assessed the sleep behavior of children and adolescents who presented at our outpatient clinic between January 2021 and May 2022 with the Children's Sleep Habits Questionnaire (CSHQ-DE). We compared sleep behavior at three different time points: pre-COVID-19, post-COVID-19 at initial presentation and post-COVID-19 at re-presentation. Data from 45 patients were analyzed. Of those, 64% were female and the median age was 10 years (range 0-18 years). Asymptomatic or mild COVID-19 disease was experienced in 89% of patients, whilst 11% experienced moderate disease. Initial presentation occurred at a median of 20.4 weeks (6 weeks - 14 months) after infection. The CSHQ-DE score increased significantly from pre-COVID-19 (45.82+8.7 points) to post-COVID-19 (49.40+8.3 points; p=<0.01). The score then normalized at re-presentation (46.98+7.8; p=0.1). The greatest changes were seen in the CSHQ-DE subscale score "daytime sleepiness". Our data show that children and adolescents with long COVID often suffer from sleep disturbance. For most children and adolescents these sleep disorders decreased over time without further medical intervention, aside from a basic sleep consultation.
ARTICLE | doi:10.20944/preprints202112.0449.v1
Subject: Behavioral Sciences, Other Keywords: behavioral economics; wearables; consumer sleep technology; Internet of Things; economical survey; expert elicitation
Online: 28 December 2021 (13:58:14 CET)
Global demand for sleep-tracking wearables, or consumer sleep technologies (CSTs), is steadily increasing. CST marketing campaigns often feature a scientific component, but the scientific relevancy and monetary value of CST features within the sleep research community remains unquantified. Sleep medicine experts were recruited through social media and nonprobability sampling techniques to complete a survey identifying sleep metrics and device features that are most desirable to the scientific community. A hypothetical purchase task (HPT) estimated economic valuation for devices with different features by price. Forty-six (N=46) respondents with an average of 10±6 years’ experience conducting research in real-world settings completed the online survey. Total sleep time was ranked as the most important measure of sleep followed by objective sleep quality while sleep architecture/depth and diagnostic information were ranked as least important. Experts preferred wrist-worn devices that could reliably determine sleep episodes as short as 20 minutes. Economic value was greater for hypothetical devices with longer battery life. These data set a precedent to determine how scientific relevance of a product impacts the potential market value of a CST device. This is the first known attempt to establish consensus opinion or economic valuation for scientifically-desirable CST features and metrics using expert elicitation.
ARTICLE | doi:10.20944/preprints202103.0234.v1
Subject: Medicine & Pharmacology, Allergology Keywords: chronic fatigue syndrome; fatigue; myalgic encephalomyelitis; melatonin; quality of life; sleep quality; zinc
Online: 8 March 2021 (16:00:25 CET)
Myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) is a complex, multisystem, and profoundly debilitating condition, probably of multifactorial etiology. No effective approved drugs are currently available for its treatment. Several studies have proposed symptomatic treatment with melatonin and zinc supplementation in chronic illnesses; however, little is known about the synergistic effect of this treatment on fatigue-related symptoms in ME/CFS. The primary endpoint of the study was to assess the effect of oral melatonin plus zinc supplementation on fatigue in ME/CFS. Secondary measures included participants’ sleep disturbances, anxiety/depression, and health-related quality of life. A proof-of-concept, 16-week, randomized, placebo-controlled, double-blind trial was conducted in 50 ME/CFS patients assigned to receive either oral melatonin (1 mg) plus zinc (10 mg) supplementation (n = 24) or matching placebo (n = 26) once daily. Endpoint outcomes were evaluated at baseline and then reassessed at 8 and 16 weeks of treatment and 4 weeks after treatment cessation, using self-reported outcome measures. Treatment was safe and well-tolerated. The most relevant results were the significant reduction in the perception of physical fatigue in the active group at the final follow-up versus placebo (p < 0.05), and the significant improvement in the physical component summary at all follow-up visits in the experimental group. Our findings suggest that oral melatonin plus zinc supplementation for 16 weeks is safe and potentially effective in reducing fatigue and improving the quality of life in ME/CFS. This clinical study was registered on ClinicalTrials.gov (NCT03000777).
ARTICLE | doi:10.20944/preprints202012.0038.v1
Subject: Medicine & Pharmacology, Allergology Keywords: physical activity; sedentary behaviour; sleep; active play; outdoor time; movement behaviours; COVID-19
Online: 1 December 2020 (16:08:08 CET)
The aim was to examine the sociodemographic predictors associated with changes in movement behaviours (physical activity, screen time and sleep) among toddlers and pre-schoolers during the early stages of the coronavirus disease 2019 pandemic in Chile. Caregivers of 1- to 5-year-old children completed an online survey between March 30th and April 27th, 2020. Information about the child's movement behaviours before (retrospectively) and during the pandemic, as well as family characteristics were reported. In total, 3,157 participants provided complete data (mean children age: 3.1±1.38 years). During early stages of the pandemic, time spent in physical activity decreased, recreational screen time and sleep duration increased, and sleep quality declined. Toddlers and pre-schoolers with space to play at home and living in rural areas experienced an attenuated impact of the pandemic restrictions on their physical activity levels, screen time, and sleep quality. Older children, those whose caregivers had a higher educational level, and children living in apartments had greater changes, mainly a decrease in total physical activity and increase in screen time. This study has shown the significant impact of the pandemic restrictions on movement behaviours in toddlers and pre-schoolers in Chile.
REVIEW | doi:10.20944/preprints202007.0373.v1
Subject: Medicine & Pharmacology, Psychiatry & Mental Health Studies Keywords: autism spectrum disorder; cannabinoids; cannabidiol; cannabidivarin; THC; problem behaviors; sleep; epilepsy; side effects.
Online: 17 July 2020 (09:19:13 CEST)
The etiopathogenesis of autism spectrum disorder (ASD) remains largely unclear. Among other biological hypotheses, researchers have evidenced an imbalance in the endocannabinoid (eCB) system, which regulates some functions typically impaired in ASD, such as emotional responses and social interaction. Also, cannabidiol (CBD), the non-intoxicating component of Cannabis sativa, has been recently approved for treatment-resistant epilepsy. Seizures represent frequent medical comorbidities of ASD and could be responsible for the onset or worsening of behavioral problems. Thus, it has been hypothesized that cannabinoids could be useful in improving some ASD symptoms. Our systematic review was conducted according to the PRISMA guidelines and aimed to summarize the literature regarding the use of cannabinoids in ASD. After searching in Web of KnowledgeTM, PsycINFO, and Embase, we included ten studies (eight papers and two abstracts). Four ongoing trials were retrieved in ClinicalTrials.gov. Findings are promising, as cannabinoids appeared to improve problem behaviors, sleep, hyperactivity, and communication deficits, with limited cardiac and metabolic side effects. Interestingly, they generally allowed to reduce the number of prescribed medications and decreased the frequency of seizures in epileptic patients. Mechanisms of action could be linked to the excitatory/inhibitory imbalance found in people with ASD. However, further trials need to be implemented with better characterization and homogenization of samples, and well-defined outcomes.
ARTICLE | doi:10.20944/preprints202005.0118.v2
Subject: Life Sciences, Biochemistry Keywords: Memory; talin; mechanobiology; information-processing; MeshCODE; brain; neuroscience; integrin; learning; cytoskeleton; REM sleep; vinculin; actin
Online: 22 October 2020 (05:40:50 CEST)
One of the major unsolved mysteries of biological science concerns the question of where and in what form information is stored in the brain. I propose that memory is stored in the brain in a mechanically encoded binary format written into the conformations of proteins found in the cell-extracellular matrix adhesions that organise each and every synapse. The MeshCODE framework outlined here represents a unifying theory of data storage in animals, providing read-write storage of both dynamic and persistent information in a binary format. Mechanosensitive proteins that contain force-dependent switches can store information persistently, which can be written or updated using small changes in mechanical force. These mechanosensitive proteins, such as talin, scaffold each synapse, creating a meshwork of switches that together form a code, the so-called MeshCODE. Large signalling complexes assemble on these scaffolds as a function of the switch patterns and these complexes would both stabilise the patterns and coordinate synaptic regulators to dynamically tune synaptic activity. Synaptic transmission and action potential spike trains would operate the cytoskeletal machinery to write and update the synaptic MeshCODEs, thereby propagating this coding throughout the organism. Based on established biophysical principles, such a mechanical basis for memory would provide a physical location for data storage in the brain, with the binary patterns, encoded in the information-storing mechanosensitive molecules in the synaptic scaffolds, and the complexes that form on them, representing the physical location of engrams. Furthermore, the conversion and storage of sensory and temporal inputs into a binary format would constitute an addressable read-write memory system, supporting the view of the mind as an organic supercomputer.
ARTICLE | doi:10.20944/preprints201902.0199.v1
Subject: Medicine & Pharmacology, Other Keywords: polymyalgia rheumatica; elderly-onset rheumatoid arthritis; sleep impairment; seronegative rheumatoid arthritis; elderly patients
Online: 21 February 2019 (09:55:22 CET)
Background: Differential diagnosis between polymyalgia rheumatica (PMR) and seronegative elderly-onset rheumatoid arthritis (SEORA) is not easy, to the point that in the past they were considered the same entity. In these patients, sleep disorders have been scarcely assessed, and considered as expression of mood disorders such as depression and anxiety. Methods: In 38 Caucasian elderly patients (median age: 73.9 ± 8.06 years) consecutively referred to two outpatient clinics from January to May 2018 with diagnosis of PMR and SEORA, sleep impairment was assessed using the Medical Outcomes Study-Sleep scale (MOS-SS). Depression and anxiety were assessed using the Neuropsychiatric Inventory (NPI) score, with point 0 for absent and point 3 for severe. Comorbidities were assessed using the Cumulative Illness Rating Scale (CIRS). Patients taking medications used to treat sleep disturbance or that could favor sleep disturbances were excluded. The study was approved by the local ethics committee and carried out in accordance with the Helsinki Declaration, revised 2013. Every patient signed an informed consent form at the time of the first visit. Results: MOS-SS total point in PMR patients was significantly higher than in SEORA patients (47.60 ± 8.4 vs 28.26 ± 12.4; P = 0.000). After six-month therapy with prednisone (12.5–15 mg/day, followed after 4 weeks by gradual tapering), MOS-SS total point improved in the two groups of patients, with no significant difference (17.0 ± 6.2 vs 17.8 ± 4.2; P = 0.644). No correlation was found between MOS-SS and comorbidities, and between MOS-SS, anxiety or depression. Conclusions: Our data suggest that the assessment of sleep impairment could be very useful in the differential diagnosis between PMR and SEORA. Up today, the reasons why patients with PMR have—at the time of diagnosis—a sleep impairment higher than SEORA are speculative. Further ad hoc complementary studies in multicenter cohorts are needed.
CASE REPORT | doi:10.20944/preprints202111.0331.v1
Subject: Medicine & Pharmacology, Oncology & Oncogenics Keywords: wearable sensor; pulse oximetry; sleep disturbance; blood oxygenation; haptic feedback; home care; oxygen concentration
Online: 18 November 2021 (14:32:09 CET)
The study reports about a case of a lung cancer patient with increasing difficulties in falling asleep and frequent periods of wakefulness. Severe dyspnea related to pneumonitis caused as a side effect of immunotherapy worsened the situation. Eventually, fear of falling asleep developed, including panic attacks and anxiety of choking, which was shown to lead to nights of complete wakefulness. The patient did not only sleep poorly; he did not sleep at all at night for several days, as evidenced by the notes he made during the night. Polygraphy showed no evidence of sleep-disordered breathing, but frequent periods of wakefulness and reduced basal saturation around 90% during sleep due to lung changes such as extensive functional failure of the left upper lobe with position-dependent shunts. The authors hypothesized that the symptoms described were causally related to a drop in oxygen saturation in the patient's blood. Therefore, they pursued the goal of finding a measurement technique that is as inexpensive as possible and that the patient can operate without outside assistance and great effort. So the patient started using a low-cost wearable device that allows simultaneous measurements of blood oxygen content, pulse rate and movement intensity. It consists of a finger ring with pulse oximetry sensor and a wristband with the control unit containing a vibration motor. The described device reliably warned of disturbances in oxygen concentration in the blood during the night with its vibration alarm. By use of that device during the whole night at home, the events of reduced oxygen saturation and the anxiety symptoms were reduced. Sleep disturbances with sudden awakenings did not occur when using the device. The patient benefited from the security gained in this way and slept much more peacefully, and he could spend nights without waking up again. In conclusion, wearable oximeters with vibration alarm can be recommended for patients’ home care in lung cancer patients.
ARTICLE | doi:10.20944/preprints202006.0150.v1
Subject: Medicine & Pharmacology, Pharmacology & Toxicology Keywords: cognitive impairment screening; cognitive reserve; subjective memory complaints; Internet; television; reading; marital status; sleep.
Online: 12 June 2020 (12:25:24 CEST)
Subjective cognitive decline (SCD) would correspond to a preclinical phase of Alzheimer's disease. The aim of this study was to find associations between lifestyle individual factors compatible scores with cognitive impairment (CI) in SCD people. Methods: This is a case-control study to detect SCD, CI and potential associated factors in 497 patients over 50 years in Community Pharmacies. Three screening tests detected possible CI and patients with at least one test compatible with CI were referred to Primary Care to be evaluated. Results: In self-complaint patients statistically significant with depressive feelings were found (86.8%) with benzodiazepines consumers (83.9%) and female patients (81.2%). Thirty percent of our sample obtained scores compatible with CI. Being older than 70 years old increased the odds of obtaining scores compatible with CI. High level education, reading and internet use were able to reduce the odds of positive scores compatible with CI (37%-91%, 7%-18% and 67%-86%), whereas, one extra hour television/day increased the risk in 8%-30%. Reading was able to nullify the effect of both internet and TV consumption. Conclusion: Not just the age but also modifiable lifestyle factors are acting in favour of a cognitive decline.
ARTICLE | doi:10.20944/preprints202207.0447.v1
Subject: Medicine & Pharmacology, Pediatrics Keywords: COVID-19 pandemic; school closures; school-aged children; physical activity; screen time; sleep; Hong Kong
Online: 29 July 2022 (03:57:32 CEST)
Despite concerns about the negative effects of social distancing and prolonged school closures on children’s lifestyle and physical activity (PA) during the COVID-19 pandemic, robust evidence is lacking on the impact of the COVID-19 pandemic on children’s wellbeing and daily life. This study aimed to examine changes in the PA levels, sleep patterns and screen time of school-aged children during the different phases of COVID-19 outbreak in Hong Kong using a repeated cross-sectional design. School students (Grades 1 to 12) were asked to report their daily electronic device usage and to fill in a sleep dairy recording their daily sleep and wake-up time. They were equipped with a PA monitor, Actigraph wGT3X-BT, to obtain objective data on their PA levels and sleep patterns. Students were recruited before the pandemic (Sep 2019 – Jan 2020; n=577), during school closures (Mar 2020 – Apr 2020; n=146), and after schools partially reopened (Oct 2020 – Jul 2021; n=227). Our results indicated lower PA levels, longer sleep duration, and longer screen time among participants recruited during school closures than those recruited before the COVID-19 outbreak. Primary school students were found to sleep on average for an extra hour during school closures. Our findings illustrate the impact of social distancing policies during the COVID-19 pandemic on the sleep pattern, screen time, and PA level in school-aged children in Hong Kong. Professionals should reinforce the importance of maintaining a physically active lifestyle, good sleep hygiene, and healthy use of electronic devices to parents and school-aged children during the COVID-19 Pandemic.
ARTICLE | doi:10.20944/preprints202204.0306.v1
Subject: Behavioral Sciences, Clinical Psychology Keywords: Fear of missing out; FoMO; social media; Social networking sites; addiction; depression; anxiety; sleep; exercise
Online: 29 April 2022 (13:50:46 CEST)
The fear of missing out (FoMO) is characterized in the literature as a fear that others are having rewarding experiences while one is missing out, and a constant need to keep connected with one’s social network. Driven by Social Determination Theory (SDT) FoMO has been linked with Problematic Social Networking Sites use (PSNSU), negative affectivity (NA), self-esteem (SE) and sleep disturbances. The present study reports findings from 512 individuals (79.1% women, mean age 30.5 years, SD= 8.61). Structural equation modelling (SEM) suggests that the duration of SNSs use and the numbers of SNSs platforms actively used partially mediated the relationship between FoMO and PSNSU. In turns, PSNSU partially mediated the relationship between FoMO and NA. Furthermore, the present study has extended the literature by incorporating the Vulnerability Model in the FoMO concept, identifying that SE partially mediated the relationship between FoMO and NA, while NA fully mediated the relationship between FoMO and sleeping disturbances. Accordingly, the present has extended previous research findings in showing exercise as a potential protective factor to prevent against FoMO. Practical and theoretical implications are discussed.
ARTICLE | doi:10.20944/preprints202107.0649.v1
Subject: Mathematics & Computer Science, Algebra & Number Theory Keywords: Sleep deficiency severity; Monte-Carlo Feature Selection; Bayesian Regression; Artificial Neural Network; Smart Health; Wearables
Online: 29 July 2021 (11:36:05 CEST)
Sleep deficiency impacts the quality of life and may have serious health consequences in the long run. Questionnaire-based subjective assessment of sleep deficiency has many limitations. On the other hand, objective assessment of sleep deficiency is challenging. In this study, we propose a polysomnography-based mathematical model for computing baseline sleep deficiency severity score and then investigated the estimation of sleep deficiency severity using features available only from wearable sensor data including heart rate variability and single-channel electroen-cephalography for a dataset of 500 subjects. We used Monte-Carlo Feature Selection (MCFS) and inter-dependency discovery for selecting the best features and removing multi-collinearity. For developing the Regression model we investigated both the frequentist and the Bayesian ap-proaches. An Artificial Neural Network achieved the best performance of RMSE = 5.47 and an R-squared value of 0.67 for sleep deficiency severity estimation. The developed method is com-parable to conventional methods of Functional Outcome of Sleep Questionnaire and Epworth Sleepiness Scale for assessing the impact of sleep apnea on sleep deficiency. Moreover, the results pave the way for reliable and interpretable sleep deficiency severity estimation using a wearable device in Smart Health.
REVIEW | doi:10.20944/preprints202107.0602.v1
Subject: Biology, Anatomy & Morphology Keywords: epigenetic mechanisms of disease; fetal programming; obstructive sleep apnea; DNA methylation; histone modifications; chronic disease
Online: 27 July 2021 (11:45:08 CEST)
Pediatric obstructive sleep apnea (OSA) has significant negative effects on health and behavior in childhood including depression, failure to thrive, neurocognitive impairment, and behavioral issues. It is strongly associated with an increased risk for chronic adult disease such as obesity and diabetes, accelerated atherosclerosis, and endothelial dysfunction. Accumulating evidence suggests that adult-onset non-communicable diseases may originate from early life through a process by which an insult applied at a critical developmental window causes long-term effects on the structure or function of an organism. Recently, much attention has been paid to the role of epigenetic mechanisms in the pathogenesis of adult disease susceptibility. Epigenetic mechanisms that influence adaptive variability include histone modifications, non-coding RNAs, and DNA methylation. This review will highlight what is currently known about the phenotypic associations of epigenetic modifications in pediatric OSA and will emphasize the importance of epigenetic changes as both modulators of chronic disease and potential therapeutic targets.
ARTICLE | doi:10.20944/preprints201810.0371.v1
Subject: Medicine & Pharmacology, Nutrition Keywords: fructose; sleep-wake cycle; locomotor activity; dopamine; orexin-A; lateral hypothalamic area; ventral tegmental area
Online: 17 October 2018 (05:39:34 CEST)
It has been widely described that chronic intake of fructose causes metabolic alterations which can be associated with brain function impairment. In this study, we evaluated the effects of fructose intake on the sleep-wake cycle, locomotion and neurochemical parameters in Wistar rats. The experimental group was fed with 10% fructose in drinking water for five weeks. After treatment, metabolic indicators were quantified in blood. Electroencephalographic recordings were used to evaluate the sleep architecture and the spectral power of frequency bands. Likewise, the locomotor activity and the concentrations of orexin A and monoamines were estimated. Our results show that fructose diet significantly increased the blood levels of glucose, cholesterol, and triglycerides. Fructose modified the sleep-wake cycle of rats increasing the waking duration and conversely decreasing the non-rapid eye movement sleep. Furthermore, these effects were accompanied by increases of the spectral power at different frequency bands. Chronic consumption of fructose caused a slight increase in the locomotor activity as well as an increase of orexin-A and dopamine levels in the hypothalamus and brainstem. Specifically, immunoreactivity for orexin-A was increased in the ventral tegmental area after the intake of fructose. Our study suggests that fructose induces metabolic changes and stimulates the activity of orexinergic and dopaminergic neurons which may be responsible for alterations of the sleep-wake cycle.
ARTICLE | doi:10.20944/preprints201807.0589.v1
Subject: Medicine & Pharmacology, Nutrition Keywords: Sleep; Social Jetlag; Diet Food and Nutrition; Nutrition Surveys; Cross-sectional; Epidemiology; Adults; Public Health
Online: 30 July 2018 (14:41:06 CEST)
Limited observational studies have described the relationship between sleep duration and overall diet. The present study investigated the association between sleep duration at weekdays and empirically derived dietary patterns in a nationally representative sample of UK adults, aged 19-64 years old, participating in the 2008-2012 UK National Diet and Nutrition Survey Rolling Programme. Survey members completed between three to four days of dietary records. Sleep duration at weekdays was categorised into tertiles to reflect short, normal and long sleep duration. Social jetlag was calculated as the difference between sleep duration at weekends and weekdays. The association between sleep duration/ social jetlag and dietary patterns, derived by principal components analysis, was assessed regressing diet on sleep whilst accounting for the complex survey design and adjusting for relevant confounders. Survey members in the highest tertile of sleep duration had on average 0.45 (95% CI -0.78, -0.12) lower healthy dietary pattern score compared to middle tertile (p =0.007). There was an inverted u-shaped association between social jetlag and a healthy dietary pattern, such that when sleep at weekends exceeded weekday sleep by 1h 45min, scores for indicating a healthy dietary pattern declined (p =0.005). In conclusion, long sleep duration at weekdays and an increased social jetlag are associated with a lower healthy dietary pattern score. Further research is required to address factors influencing dietary patterns in long sleepers.
ARTICLE | doi:10.20944/preprints202111.0041.v1
Subject: Engineering, Biomedical & Chemical Engineering Keywords: Obstructive sleep apnea; Continuous positive airways pressure therapy; Near-infrared spectroscopy; Oxygen desaturation; Arm; Pulse oximeter
Online: 2 November 2021 (10:52:45 CET)
Obstructive sleep apnea (OSA) is a common sleep disorder, and continuous positive airways pressure (CPAP) is the most effective treatment. Poor adherence is one of the major challenges in CPAP therapy. The recent boom of wearable optical sensors measuring oxygen saturation makes the at-home multiple-night CPAP titrations possible, which may essentially improve the adherence of CPAP therapy by optimizing its pressure in a real-life setting economically. We tested whether the oxygen desaturations (OD) measured in the arm muscle (arm_OD) by gold-standard frequency-domain multi-distance near-infrared spectroscopy (FDMD-NIRS) changes with titrated CPAP pressures in OSA patients together with polysomnography. We found that the arm_OD (2.08 ± 1.23%, mean ± standard deviation) was significantly smaller (P-value <0.0001) than the fingertip OD (finger_OD) (4.46 ± 2.37%) measured by polysomnography pulse oximeter. Linear mixed-effects models suggested that CPAP pressure was a significant predictor for finger_OD but not for arm_OD. Since FDMD-NIRS measures a mixture of arterial and venous OD, whereas fingertip pulse oximeter measures arterial OD, our results of no association between arm_OD and finger_OD indicate that the arm_OD mainly represented venous desaturation. Arm_OD measured by near-infrared optical sensors may be not a suitable indicator of the effectiveness of CPAP titration.
ARTICLE | doi:10.20944/preprints202110.0345.v1
Subject: Medicine & Pharmacology, Cardiology Keywords: Loss of consciousness; Mental health; Working life; Effort Reward Imbalance; Sleep Dis-orders; Health promotion; Workplace
Online: 25 October 2021 (11:54:17 CEST)
Syncope and presyncope occurring during work can affect safety and impair occupational performance. Few data are available regarding the prevalence of these events among workers. The possible role of sleep quality, mental stress and metabolic disorders in promoting syncope, presyncope and falls in workers is unknown. In the present study, 741 workers (male 35.4%; mean age 47±11 years), employed in different companies, underwent clinical evaluation and blood tests and completed questionnaires to assess sleep quality, occupational distress and mental disorders. The occurrence of syncope, presyncope and unexplained falls during their working life was assessed by an ad hoc interview. The prevalence of syncope, presyncope and falls of unknown origin was 13.9%, 27.0%, and 10.3%, respectively. The occurrence of syncope was associated with an increased risk of occupational distress (adjusted Odds Ratio aOR: 1.62, Confidence Intervals at 95%: 1.05-2.52), low sleep quality (aOR: 1.79 CI 95%: 1.16-2.77) and poor mental health (aOR: 2.43 CI 95%: 1.52-3.87). Presyncope was strongly associated with occupational distress (aOR: 1.77 CI 95%: 1.25-2.49), low sleep quality (aOR: 2.95 CI 95%: 2.08-4.18) and poor mental health (aOR: 2.61 CI 95%: 1.78-3.84), while no significant relationship was found between syncope or presyncope and metabolic syndrome. These results suggest that occupational health promotion interventions aimed at improving sleep quality, reducing stressors and increasing worker resilience might reduce syncope and presyncope events in the working population.
REVIEW | doi:10.20944/preprints202101.0461.v1
Subject: Life Sciences, Biochemistry Keywords: Diuretic hormone; sleep, feeding; metabolism; ion transport peptide; tachykinin; short neuropeptide F; insulin-like peptide; neuromodulation
Online: 25 January 2021 (09:23:22 CET)
Leucokinins (LKs) constitute a family of neuropeptides identified in numerous insects and many other invertebrates. The LKs act on G-protein coupled receptors that display only distant relations to other known receptors. In adult Drosophila, 26 neurons/neurosecretory cells of three main types express LK. The four brain interneurons are of two types, and these are implicated in several important functions in the fly’s behavior and physiology, including feeding, sleep-metabolism interactions, state-dependent memory formation, as well as modulation of gustatory sensitivity and nociception. The 22 neurosecretory cells (ABLKs) of the abdominal neuromeres coexpress LK and a diuretic hormone (DH44), and together these regulate water and ion homeostasis and associated stress, as well as food intake. In Drosophila larvae, LK neurons modulate locomotion, escape responses, and aspects of ecdysis behavior. A set of lateral neurosecretory cells, ALKs, in the brain express LK in larvae, but inconsistently so in adults. These ALKs coexpress three other neuropeptides and regulate water and ion homeostasis, feeding and drinking, but the specific role of LK is not yet known. This review summarizes Drosophila data on embryonic lineages of LK neurons, functional roles of individual LK neuron types, interactions with other peptidergic systems, and orchestrating functions of LK.
ARTICLE | doi:10.20944/preprints202002.0186.v1
Subject: Medicine & Pharmacology, Anesthesiology Keywords: breakthrough cancer pain; cancer-associated pain; cancer; health-related quality of life; sleep disorders; transmucosal fentanyl
Online: 14 February 2020 (03:36:53 CET)
Objectives: To explore the effect of breakthrough cancer pain (BTcP) treatment on quality of sleep and other aspects of the health-related quality of life (HRQoL) in patients with cancer pain. Methods: In an observational, multicenter, cohort study, cancer patients from palliative care units, oncology departments, and pain clinics and affected by BTcP were included. Enrolled patients were assessed at the four visits: T0 (baseline), T7, T14, and T28. Well-controlled chronic background pain during the whole study period was mandatory. BTcP was treated through transmucosal fentanyl. Three questionnaires were used to measure the HRQoL: EORTC QLQ-C15-PAL, Pittsburgh Sleep Quality Index (PSQI), and the Edmonton Symptom Assessment System (ESAS). Results: In 154 patients, the HRQoL showed a significant improvement for all physical and emotional characteristics in the EORTC QLQ-C15-PAL, except for nausea and vomiting (Linear p-value = 0.1) and dyspnoea (Linear p-value =0.05). The ESAS and PSQI questionnaires confirmed these positive results (p<0.0001 and p=0.002, respectively). Conclusions: This prospective investigation by an Italian expert group, has confirmed that careful management of BTcP induces a paramount improvement on the HRQoL. Because in cancer patients there is a high prevalence of BTcP and this severe acute pain has deleterious consequences, this information can have an important clinical significance
REVIEW | doi:10.20944/preprints201806.0054.v1
Subject: Medicine & Pharmacology, Behavioral Neuroscience Keywords: Lyme disease; Borrelia burgdorferi; tickborne diseases; persistent infection; treatment; assessment; depression; anxiety; sleep disorders; opioid addiction
Online: 5 June 2018 (08:33:20 CEST)
There is increasing evidence and recognition that Lyme borreliosis, and other associated tick-borne diseases (LB/TBD) cause mental symptoms. Data was drawn from databases, search engines and clinical experience to review current information on LB/TBD. LB/TBD infections cause immune and metabolic effects that result in a gradually developing spectrum of neuropsychiatric symptoms, usually presenting with significant comorbidity and may include developmental disorders, autism spectrum disorders, schizoaffective disorders, bipolar disorder, depression, anxiety disorders (panic disorder, social anxiety disorder, generalized anxiety disorder, posttraumatic stress disorder, intrusive symptoms), eating disorders, decreased libido, sleep disorders, addiction, opioid addiction, cognitive impairments, dementia, seizure disorders, suicide, violence, anhedonia, depersonalization, dissociative episodes, derealization and other impairments. Screening assessment followed by a comprehensive psychiatric clinical exam relevant to patient’s complaints and findings with a thorough history, mental status exam, review of systems, neurological exam, physical exam, a knowledgeable interpretation of laboratory findings, pattern recognition and clinical judgment facilitate diagnosis. Psychotropics and antibiotics may help improve functioning and prevent further disease progression. Awareness of the association between LB/TBD and neuropsychiatric impairments and studies of their prevalence in neuropsychiatric conditions can improve understanding of the causes of mental illness and violence and result in more effective prevention, diagnosis and treatment.
ARTICLE | doi:10.20944/preprints202303.0430.v1
Subject: Medicine & Pharmacology, Psychiatry & Mental Health Studies Keywords: COVID-19; Endurance athletes; mental health; sleep; cardiopulmonary exercise testing; cardiorespiratory fitness; exercise capacity; physical exercise; psychology
Online: 24 March 2023 (12:23:44 CET)
COVID-19 has harmful impact on health. It is especially important for endurance athletes (EAs). Sleep and psychology influence sport performance. Aims of this study were: (1) investigation of the consequences of mild COVID-19 on sleep and psychology and (2) assessment of the conse-quences of the infection on cardiopulmonary exercise test (CPET) results. 49 EAs (males= 43; 87.76%, females= 6; 12.24%, age= 39.9±7.8 years, height= 178.4±6.8 cm, weight= 76.3±10.4 kg; BMI= 24.0±2.6 kg·m−2) underwent maximal cycling or running CPET pre- and post- COVID-19 and completed a survey. Exercise performance was deteriorated after COVID-19 (maximal oxy-gen uptake; VO2max= 47.81±7.81 vs 44.97±7.00 ml·kg·min−1 respectively pre- and post- infection; p<0.001). Waking up at night affected heart rate (HR) at the respiratory compensation point (RCP) (p=0.028). Sleep time influenced pulmonary ventilation (p=0.013), breathing frequency (p=0.010), and blood lactate concentration (Lac) (p=0.013) at RCP. Maximal power/speed (p=0.046) and HR (p=0.070) linked with the quality of sleep. Stress management and relaxation techniques linked with VO2max (p=0.046), maximal power/speed (p=0.033), and maximal Lac (p=0.045). Cardiorespiratory fitness was deteriorated after mild COVID-19 and was correlated with sleep and mental health. Medical Professionals should encourage EAs to maintain proper mental health and sleep after COVID-19 infection to facilitate recovery.
REVIEW | doi:10.20944/preprints202205.0029.v1
Subject: Mathematics & Computer Science, Information Technology & Data Management Keywords: Sleep tracking; Context aware recommender system; Quantified self; Personal informatics; Ubiquitous computing; Mobile computing; mHealth; CBI-I
Online: 5 May 2022 (09:34:09 CEST)
The practice of quantified-self sleep tracking is increasingly common nowadays among healthy individuals as well as patients with sleep problems. However, existing sleep-tracking technologies only support simple data collection and visualization, and are incapable of providing actionable recommendations that are tailored to users' physical, behavioral and environmental context. Here we coined the term context-aware sleep health recommender system (CASHRS) as an emerging multidisciplinary research field that bridges ubiquitous sleep computing and context-aware recommender systems. In this paper, we presented a narrative review to analyze the type of contextual information, the recommendation algorithms, the context filtering techniques, the behavior change techniques, the system evaluation, and the challenges in peer-reviewed publications that meet the characteristics of CASHRS. Analysis results identified current research trends, the knowledge gap, and future research opportunities in CASHRS.
ARTICLE | doi:10.20944/preprints202112.0284.v1
Subject: Medicine & Pharmacology, Other Keywords: Retina; Retinal nerve fiber layer; Obstructive sleep apnea syndrome; Optical coherence tomography; OCT; CPAP; Upper airway surgery.
Online: 17 December 2021 (08:47:15 CET)
Retinal findings may change in patients with obstructive sleep apnea syndrome (OSAS). The present study aims to evaluate several retinal findings such as macula layer thickness, peripapillary retinal nerve fiber layer, and the optic nerve head in patients with OSAS using optical coherence tomography (OCT) and monitor the result of several types of treatment of OSAS with OCT. A prospective comparative study was designed. Patients were recruited at a Sleep Unit of a University Hospital and underwent comprehensive ophthalmological examinations. Following exclusion criteria, fifty-two patients with OSAS were finally included. Patients were examined by OCT twice: first, before treatment; secondly, after six months of treatment. In mild-moderate patients, where retinal swelling has been demonstrated, retinal thicknesses decreased [fovea (p=0.026), as well as inner ring macula (p=0.007), outer ring macula (p=0.015), and macular volume (p=0.015)]. In severe patients, where retinal atrophy had been observed, retinal thickness increased [fovea (p<0.001)]. No statistically significant differences in efficacy between treatments were demonstrated. In conclusion, OCT can evaluate the retina in patients with OSAS and help monitor results after treatment. In severe OSAS, retinal thickness increased six months after treatment.
Subject: Medicine & Pharmacology, General Medical Research Keywords: bed bugs; Cimex spp.; Hong Kong; sleep disturbance; health impact; public health; causal agent; infectious agent; vector
Online: 6 October 2021 (09:09:17 CEST)
Bedbug (Cimex spp.) are a nuisance public-health pest that is on the rise globally, particularly in crowded cities such as Hong Kong. To investigate the health impacts of bedbug infestations among bedbug victims, online surveys were distributed in Hong Kong between June 2019 to July 2020. Data on sociodemographics, self-rated health, average hours of sleep per day, and details of bedbug infestation were collected. Bivariate and multivariable analysis were performed using logistic regression. The survey identified 422 bedbug victims; among them, 223 (52.9%) experienced ≥5 bites in the past month, most bites occurred on the arms (n=202, 47.8%) and legs (n=215, 51%), and the most common reaction to bites were itchiness (n=322, 76.3%), redness, and swelling of the skin (n=246, 58.1%), and difficulties sleeping or restlessness (n=125, 29.6%). Bites usually occurred during sleep (n=230, 54.5%). For impact on daily life in the past month, most bedbug victims reported moderate to severe impact on mental and emotional health (n=223, 52.8%) and sleeping quality (n=239, 56.6%). Lower self-rated health (aOR<1) was independently associated with impact to physical appearance (p=0.008), spending money on medication or doctor consultation (p=0.04), number of bites in the past month (p=0.023), and irregular time of bites (p=0.003). Lower average hours of sleep per day (aOR<1) was independently associated with impact on mental and emotional health (p=0.016). This study brings attention to the neglected issue of bedbug infestation by considering bedbugs as an infectious agent instead of a vector and providing empirical evidence describing its health impacts.
ARTICLE | doi:10.20944/preprints201909.0094.v1
Subject: Medicine & Pharmacology, Other Keywords: sleep quality; road traffic noise; actimetry; indoor noise; noise measurements; noise annoyance; noise sensitivity; time of day
Online: 9 September 2019 (08:45:43 CEST)
It is unclear which noise exposure time window and noise characteristics during nighttime are most detrimental for sleep quality in real life settings. We have conducted a field study with 105 volunteers wearing a wrist actimeter to record their sleep during seven days, together with concurrent outdoor noise measurements at their bedroom window. Actimetry recorded sleep latency increased by 5.6 minutes (95% confidence interval: 1.6 to 9.6 minutes) per 10 dB(A) increase in noise exposure during the first hour after bedtime. Actimetry assessed sleep efficiency was significantly reduced by 2-3 percent per 10 dB(A) increase in measured outdoor noise (Leq, 1h) for the last three hours of sleep. For subjectively reported sleepiness, noise exposure during the last hour prior to wake up was most crucial with an increase in the sleepiness score of 0.31 units (95% CI: 0.08 to 0.54) per 10 dB(A) Leq,1h. Associations for estimated indoor noise were not more pronounced than for outdoor noise. Considering noise events in addition to equivalent sound pressure levels (Leq) only marginally improved the statistical models. Our study provides evidence that matching the nighttime noise exposure time window to the individual’s diurnal sleep-wake pattern results in a better estimate of detrimental nighttime noise effects on sleep. We found that noise exposure at the beginning and the end of the sleep is most crucial for sleep quality.