Evaluating Suicidal Ideation and Anhedonic Symptoms in Obstructive Sleep Apnea Patients with Insomnia

ObjectiveInsomnia and obstructive sleep apnea (OSA) are prevalent in the geriatric population, with co-morbid insomnia and sleep apnea (COMISA) increasing the risk of suicidal ideation. Anhedonia, a core depression feature, is associated with suicidal ideation. This study aimed to explore the relationship between COMISA and suicidality including the mediating effect of anhedonic symptoms.MethodsFrom August 2021 to December 2023, 243 participants from South Korea were enrolled in a prospective case-control study at a Veterans' hospital. Participants underwent interviews, self-report measures, and polysomnography. 214 untreated OSA participants were categorized into COMISA and OSA-only groups. Anhedonic symptoms and their correlates were investigated.Results69 participants (32.2%) had an Insomnia Severity Index score >15, forming the COMISA group. Suicidal ideation was more prevalent in the COMISA group (43.1% vs 23.4%, P = 0.007). After adjusting for covariates such as age, gender, body mass index, alcohol and smoking consumption, caffeine intake, hypertension, diabetes mellitus, and sleep-related factors, the odds of suicidal ideation were higher in the COMISA group (OR = 2.42, 95% CI = 1.14 - 5.11). However, after adjusting for anhedonic symptoms, this association was no longer significant. Anhedonic symptoms mediated the relationship between insomnia and suicidal ideation (OR = 1.045, 95% CI = 1.013-1.074).ConclusionsThe findings of this study underscore the emergence of suicidal ideation among individuals with COMISA. Understanding the mechanisms of anhedonic symptoms underlying the relationship between COMISA and suicidal ideation is crucial for developing targeted interventions to mitigate suicidality in this population.