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Patterns of Suicide Attempt Presentations in Emergency Departments: A Population-Based Cross-Sectional Study (2018–2024)

Submitted:

05 August 2026

Posted:

06 August 2026

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Abstract
Background: Suicide represents a major global public health challenge, and suicide attempts are among the strongest predictors of subsequent suicide. Despite their importance, Portugal lacks comprehensive national epidemiological evidence on suicide attempts presenting to emergency departments, limiting the development of targeted prevention strategies and informed public health policy. Objective: To examine temporal trends and describe the sociodemographic and clinical characteristics of emergency department presentations for suicide attempts in Portugal between 2018 and 2024.Design: Population-based cross-sectional study. Methods: We conducted a population-based analysis of mandatory nationwide emergency department records from 2018 to 2024. Suicide attempts were identified using ICD-10 diagnostic codes. Age-standardized rates were calculated using the WHO World Standard Population. Temporal trends were evaluated using Joinpoint log-linear regression to estimate annual percentage changes (EAPCs) and corresponding 95% confidence intervals (CIs), overall and by sex. Results: A total of 158,937 emergency department presentations for suicide attempts were identified, representing 0.25% of all emergency department visits during the study period. Age-standardized rates remained relatively stable, decreasing from 85.80 to 76.38 per 100,000 population (EAPC = −3.9%, 95% CI: −14.1% to 7.5%). Self-poisoning was the predominant method, accounting for 98.7% of all presentations. The highest burden was observed among individuals aged 15–29 years and ≥65 years, and most cases were managed in second-level Ministry of Health (MINSA) facilities. Substantial regional variation in presentation rates was observed across the country. Conclusions: Emergency department presentations for suicide attempts remained largely stable in Portugal between 2018 and 2024 despite considerable regional disparities. The concentration of presentations among adolescents and young adults and older adults, together with the predominance of self-poisoning, highlights the need for age-specific suicide prevention strategies, strengthened emergency department surveillance, and interventions aimed at reducing access to commonly used lethal means.
Keywords: 
suicide attempt
;  
emergency department
;  
epidemiology
;  
time trends
;  
Portugal
;  
population-based study
Subject: 
Medicine and Pharmacology  -   Psychiatry and Mental Health

Introduction

Suicide remains one of the leading causes of preventable mortality worldwide and is recognized by the World Health Organization [1,2] as a major public health priority. More than 700,000 people die by suicide each year, representing only a fraction of the overall burden of suicidal behavior. For every suicide death, an estimated 20–30 suicide attempts occur, making non-fatal suicidal behavior a critical target for prevention efforts [1−3]. Individuals who attempt suicide are at substantially increased risk of subsequent attempts and suicide death, highlighting the importance of timely identification and intervention.
Emergency departments play a pivotal role in the management of suicidal behavior, serving as the principal point of contact with the healthcare system for many individuals following a suicide attempt. Consequently, emergency department data provide an essential source of information for monitoring the epidemiology of suicidal behavior, identifying high-risk populations, evaluating temporal trends, and informing evidence-based prevention strategies.
In Portugal, suicide mortality has shown an upward trend over the past decade, reinforcing the need to strengthen national suicide prevention policies [4]. However, despite the availability of nationwide emergency department records, there is limited epidemiological evidence describing the burden, characteristics, and temporal evolution of suicide attempts requiring emergency care. Unlike several high-income countries that routinely use emergency department surveillance to guide suicide prevention initiatives, Portugal lacks comprehensive national analyses of these presentations [5]. This evidence gap constrains health service planning, resource allocation, and the implementation of targeted clinical and public health interventions.
The present study aimed to examine national trends in emergency department presentations for suicide attempts in Portugal between 2018 and 2024. Specifically, we described the sociodemographic and clinical characteristics of these presentations and evaluated temporal changes over the study period. By providing the first nationwide epidemiological characterization of emergency department presentations for suicide attempts in Portugal, this study offers robust evidence to support surveillance systems, guide healthcare planning, and inform the development of targeted suicide prevention policies.

Methods

Study Design

We conducted a nationwide population-based cross-sectional study of emergency department presentations for suicide attempts between 2018 and 2024. The study was reported in accordance with the Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) guidelines [6]. Portugal has an estimated population of approximately 10.5 million inhabitants and provides universal healthcare through the Portuguese National Health Service (Serviço Nacional de Saúde, SNS), complemented by private healthcare providers.

Data Source and Study Population

Data were obtained from the Portuguese National Health Service (SNS) national database of mandatory emergency department records, covering the period from January 1, 2018, to December 31, 2024. All emergency department presentations with a diagnosis of suicide attempt were identified using the International Classification of Diseases, Tenth Revision (ICD-10). Variables extracted included the year of presentation, patient’s age and sex, geographic region, healthcare facility level, and method of suicide attempt.

Variables

Suicide attempts were identified using ICD-10 external cause codes for intentional self-harm. Methods were classified as self-poisoning (X60–X69), hanging or suffocation (X70), drowning (X71), firearm discharge (X72–X74), cutting or piercing (X78), and other or unspecified methods according to the ICD-10 classification. Sociodemographic variables included sex and age, categorized into five-year age groups. Geographic distribution was defined according to the region of the reporting healthcare facility. Healthcare facilities were classified according to their level of complexity (Levels I–III), reflecting the organization of emergency care services within the Portuguese National Health Service (SNS).

Methods

Study Design

We conducted a nationwide population-based cross-sectional study of emergency department presentations for suicide attempts in Portugal between 2018 and 2024. The study was reported in accordance with the Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) guidelines [6]. Portugal has an estimated population of approximately 10.5 million inhabitants and provides universal healthcare through the Portuguese National Health Service (Serviço Nacional de Saúde, SNS), complemented by private healthcare providers.

Data Source and Study Population

Data were obtained from the Portuguese National Health Service (SNS) national database of mandatory emergency department records, covering the period from 1 January 2018 to 31 December 2024. The database comprises routinely collected records from emergency departments across the country. All emergency department presentations with a diagnosis of suicide attempt were identified using the International Classification of Diseases, Tenth Revision (ICD-10). Variables extracted included the year of presentation, patient’s age and sex, geographic region, healthcare facility level, and method of suicide attempt.

Variables

Suicide attempts were identified using ICD-10 external cause codes for intentional self-harm. Methods of suicide attempt were categorized as self-poisoning (X60–X69), hanging or suffocation (X70), drowning (X71), firearm discharge (X72–X74), cutting or piercing (X78), and other or unspecified methods according to the ICD-10 classification. Sociodemographic variables included sex and age, categorized into five-year age groups. Geographic distribution was defined according to the region of the reporting healthcare facility. Healthcare facilities were classified according to their level of complexity (Levels I–III), reflecting the organization of emergency care services within the Portuguese National Health Service (SNS).

Statistical Analysis

Descriptive statistics were used to summarize the annual distribution of emergency department presentations for suicide attempts. Age-standardized rates were calculated per 100,000 population using the WHO World Standard Population to facilitate comparisons across calendar years [9].
Temporal trends in age-standardized rates were evaluated using Joinpoint log-linear regression models, overall and stratified by sex. Joinpoint regression identifies statistically significant changes in temporal trends by estimating points at which the slope changes over time. For each trend segment, the annual percentage change (APC) and its corresponding 95% confidence interval (CI) were estimated. The average annual percentage change (AAPC) was calculated to summarize the overall trend during the study period (2018–2024).
Regression models were fitted on the natural logarithm of the age-standardized rates and weighted by the standard errors of the rates to account for heteroscedasticity. All statistical analyses were performed using R version 4.5.1 (R Foundation for Statistical Computing, Vienna, Austria). Statistical significance was defined as a two-sided p value < 0.05.

Ethical Considerations

This study was based on secondary analysis of anonymized administrative data obtained from the Portuguese National Health Service (Serviço Nacional de Saúde, SNS). As the dataset contained no personally identifiable information and all analyses were conducted using anonymized records, ethics committee approval and informed consent were not required under Portuguese legislation governing research using secondary health data.

Results

Between 2018 and 2024, a total of 158,937 emergency department presentations for suicide attempts were identified, accounting for 0.25% of all emergency department visits during the study period. The annual proportion of suicide attempt-related presentations remained relatively stable over time. The distribution by sex was broadly balanced, although the decline in age-standardized rates was more pronounced among men than among women.
The highest proportion of presentations occurred among young adults aged 20–24 years (14.2%), followed by adolescents aged 15–19 years (13.7%) and older adults (10.4%). Self-poisoning was the predominant method of suicide attempt, accounting for 98.7% of all presentations. Most patients were treated in Level II hospitals within the Portuguese National Health Service, highlighting the central role of secondary-level emergency departments in the management of suicidal behavior.
Age-standardized suicide attempt rates declined between 2018 and 2024. However, Joinpoint regression analysis showed no statistically significant temporal trend in the overall population (EAPC = −3.9%; 95% CI: −14.1% to 7.5%; p = 0.404). Similarly, no statistically significant changes were observed after stratification by sex, either among men (EAPC = −6.2%; p = 0.232) or women (EAPC = −1.6%; p = 0.712).
Marked geographical variation in age-standardized suicide attempt rates was observed across Portugal throughout the study period. Although the national trend remained stable, substantial regional differences persisted, with some regions consistently reporting higher rates than others.

Discussion

This nationwide population-based study provides, to our knowledge, the first comprehensive analysis of emergency department presentations for suicide attempts in Portugal over a seven-year period. Three principal findings emerged. First, although age-standardized suicide attempt rates showed a modest numerical decline between 2018 and 2024, Joinpoint regression did not identify a statistically significant temporal trend, indicating that the overall burden of suicide attempt presentations remained largely stable. Second, presentations were concentrated among adolescents, young adults, and older adults, highlighting two vulnerable age groups that require particular attention within suicide prevention strategies. Third, self-poisoning was by far the most frequently recorded method of suicide attempt, accounting for nearly all emergency department presentations.
The apparent stability in suicide attempt rates contrasts with the widespread perception that suicidal behavior has increased substantially in recent years. While fluctuations were observed throughout the study period, these did not translate into statistically significant changes after adjustment for age or stratification by sex. This finding suggests that, at the population level, the burden of suicide attempts requiring emergency care has remained relatively constant. Nevertheless, the persistence of high numbers of presentations underscores the continuing public health importance of suicidal behavior in Portugal.
The predominance of adolescents, young adults, and older adults among emergency department presentations is consistent with previous international research demonstrating that suicidal behavior follows a bimodal age distribution. Adolescence and early adulthood are characterized by major developmental, educational, occupational, and social transitions, whereas later life is frequently associated with chronic disease, social isolation, bereavement, and functional decline. These life-course transitions may increase vulnerability to suicidal behavior and emphasize the need for age-specific prevention and intervention strategies.
Self-poisoning represented the overwhelming majority of suicide attempts in this study, a finding that is consistent with reports from other European countries. Because self-poisoning is commonly associated with the availability of medications and toxic substances, restricting access to commonly used means, improving medication safety, and strengthening community-based mental health services may contribute to reducing suicide attempts. Although less frequent, highly lethal methods warrant continued surveillance because of their greater association with suicide mortality.
An important finding was the marked geographical variation observed across Portugal. Although the national trend remained stable, regional differences suggest that the burden of suicidal behavior is not uniformly distributed. These disparities may reflect differences in socioeconomic conditions, demographic composition, availability of mental health services, healthcare access, or clinical coding practices. Further investigation is needed to identify the determinants of these regional patterns and to support targeted prevention strategies.
From a clinical perspective, our findings support the implementation of a standardized emergency department management pathway for patients presenting after a suicide attempt within the Portuguese National Health Service. Such a pathway should include: (1) immediate medical stabilization and triage; (2) standardized suicide risk assessment using a validated instrument; (3) comprehensive psychiatric evaluation before discharge; (4) stratification into low-, moderate-, and high-risk categories to guide clinical decision-making; (5) development of an individualized Safety Plan, including restriction of access to lethal means and involvement of family or caregivers whenever appropriate; (6) referral to community mental health services or psychiatric hospitalization according to the assessed level of risk; and (7) proactive follow-up, ideally within 48–72 hours after discharge, with continuity of care in specialized mental health services. Implementing a structured protocol across Portuguese emergency departments may improve the consistency of clinical management, reduce variation in practice, strengthen continuity of care, and contribute to reducing the risk of repeat suicide attempts.
This study has several strengths. It is based on a large nationwide dataset including more than 100,000 emergency department presentations over seven years, providing comprehensive population coverage and allowing the assessment of temporal and geographical patterns at the national level. The use of standardized ICD-10 coding and age-standardized rates further enhances the comparability of the findings.
Several limitations should also be acknowledged. First, the study relied on routinely collected administrative data, which may be subject to coding errors and variability in diagnostic practices across healthcare institutions. Second, the database captures only suicide attempts resulting in emergency department presentations and therefore does not include episodes managed exclusively in primary care or those that did not receive medical attention, potentially underestimating the true burden of suicidal behavior. Third, the available data did not include important individual-level variables such as psychiatric diagnoses, previous suicide attempts, socioeconomic status, substance use, or access to mental health services, precluding adjustment for potential confounders. Finally, because of the cross-sectional design, causal relationships cannot be established.
Overall, these findings provide important epidemiological evidence on suicide attempt presentations within the Portuguese National Health Service. Despite the absence of significant temporal changes, the sustained number of emergency department presentations, the concentration of cases among adolescents, young adults, and older adults, and the substantial regional variation indicate that suicide attempts remain a persistent public health challenge. Future research should integrate emergency department data with mortality records and mental health information systems to improve surveillance, identify high-risk populations, and evaluate the effectiveness of standardized emergency care pathways and targeted suicide prevention strategies.

Conclusion

Overall, these findings provide important epidemiological evidence on suicide attempt presentations within the Portuguese National Health Service (SNS). Despite the absence of significant temporal changes, the sustained number of emergency department presentations, the concentration of cases among adolescents, young adults, and older adults, and the marked regional variation indicate that suicide attempts remain a persistent public health challenge requiring coordinated, evidence-based interventions.
Beyond their epidemiological relevance, these findings have important implications for clinical practice. The predominance of self-poisoning and the high volume of emergency department presentations support the implementation of a standardized national protocol for the assessment and management of patients presenting after a suicide attempt within the SNS. Standardization would reduce variability in clinical practice, facilitate early identification of high-risk individuals, and improve continuity of care following discharge.
A proposed emergency department management pathway should include seven sequential steps: (1) immediate medical stabilization and triage; (2) systematic suicide risk assessment using a validated instrument together with a comprehensive psychosocial and psychiatric evaluation; (3) identification of dynamic and static risk factors, protective factors, previous suicide attempts, psychiatric comorbidities, and access to lethal means; (4) individualized safety planning, including restriction of access to medications or other potential means of suicide, identification of warning signs, coping strategies, emergency contacts, and involvement of family members or caregivers whenever appropriate; (5) risk stratification to determine the need for discharge with structured follow-up or psychiatric hospitalization; (6) referral to community mental health services with a scheduled appointment before discharge; and (7) proactive follow-up, ideally within 48–72 hours after discharge, to reinforce adherence to treatment, monitor suicide risk, and facilitate continuity of care. This structured approach is consistent with contemporary cognitive-behavioural interventions for suicidal behaviour, which emphasize collaborative safety planning, cognitive restructuring, development of coping skills, crisis response planning, and continuity of therapeutic care.
The implementation of a standardized national pathway across ortuguese emergency departments could improve the quality and consistency of care, facilitate communication between emergency physicians, psychiatrists, psychologists, and primary care professionals, and reduce fragmentation in post-discharge management. Such an approach would also strengthen surveillance by promoting standardized clinical documentation and facilitating linkage between emergency department, psychiatric, and mortality databases.
This study has several strengths. It is based on a large nationwide dataset including more than 158,000 emergency department presentations over seven years, providing comprehensive population coverage and allowing the assessment of temporal and geographical patterns at the national level. The use of standardized ICD-10 coding and age-standardized rates further enhances the comparability of the findings.
Several limitations should also be acknowledged. First, the study relied on routinely collected administrative data, which may be subject to coding errors and variability in diagnostic practices across healthcare institutions. Second, the database captures only suicide attempts resulting in emergency department presentations and therefore does not include episodes managed exclusively in primary care or those that did not receive medical attention, potentially underestimating the true burden of suicidal behaviour. Third, the available data did not include important individual-level variables such as psychiatric diagnoses, previous suicide attempts, socioeconomic status, substance use, or access to mental health services, precluding adjustment for potential confounders. Finally, because of the cross-sectional design, causal relationships cannot be established.
Future research should evaluate the effectiveness of implementing a standardized emergency department protocol within the Portuguese National Health Service, integrating epidemiological surveillance with longitudinal clinical follow-up and national mortality records. Such an approach would enable more accurate identification of individuals at highest risk of repeated suicide attempts and suicide death, while providing robust evidence to inform national suicide prevention policies.

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