Prevalence of Insomnia and Associated Factors in Patients with Prostate Cancer Receiving Systemic Treatment

Background and Objectives: Insomnia is a prevalent yet underrecognized symptom in patients with prostate cancer, and evidence in patients receiving systemic treatment is limited. We assessed the prevalence of insomnia and its associated factors in this population. Materials and Methods: In this two-center, cross-sectional study, insomnia was assessed with the Turkish version of the Insomnia Severity Index (ISI) in patients with metastatic prostate cancer receiving systemic treatment. Insomnia was defined as an ISI score ≥ 8 and clinical insomnia as an ISI score ≥ 15. Results: Among 110 patients, insomnia was present in 52 (47.3%) and clinical insomnia in 15 (13.6%). Pain (adjusted OR, 7.06; 95% CI, 2.31–21.59; p = 0.001) and a higher last prostate-specific antigen (PSA) level (OR per 10-fold increase, 1.47; 95% CI, 1.02–2.12; p = 0.040) were independently associated with insomnia. Clinical insomnia was more frequent in patients with visceral metastasis (50.0% vs. 9.4%; p = 0.008). Insomnia did not differ by treatment group or time on androgen deprivation therapy. Conclusions: Nearly half of these patients have insomnia, associated mainly with pain and active disease. Routine insomnia screening and pain management are warranted.