739 Association of hospital-diagnosed sleep disorders with suicide: A nationwide cohort study

Abstract

Abstract Introduction Sleep disorders and psychiatric disease are closely related, and psychiatric diseases are associated with elevated suicide risks. Yet, it is not clear if sleep disorders are associated with suicide as previous studies were limited by self-reported measures. The aim of this study was to examine whether people with a hospital-diagnosis of sleep disorders had higher suicide rates than people with no diagnosis. Methods Using a retrospective cohort design, national data on all persons aged 15 years and over who lived in Denmark during 1980–2016 (males: 3,674,563, females: 3,688,164) were obtained. People with sleep disorders were identified in somatic hospital registers. The main outcome was death by suicide as recorded in the Danish Cause of Death register. Incidence Rate Ratios were obtained using Poisson regressions while adjusting for relevant covariates. Results Out of 23,927 male and 11,556 female suicide deaths, 299 and 117 had been diagnosed with a sleep disorder, respectively. Males with sleep disorders had a suicide rate of 47.4 (95% CI, 42.0–52.7) per 100,000 person-years compared to 29.9 (95% CI, 29.5–30.3) among those with no sleep disorders. For females the respective rates were 42.3 (95% CI, 34.7–50.0) versus 13.9 (95% CI, 13.6–14.1). An adjusted IRR of 1.6 (95% CI, 1.4–1.7) and 2.2 (95% CI, 1.8–2.6) was noted among males and females with sleep disorders, respectively, when compared to those with no disorders. Excess rates were noted with respect to insomnia, narcolepsy and, in males, sleep apnea. A difference with respect to age and sex was observed (p<0.001). Furthermore,IRRs of 4.1(95% CI, 3.1–5.5) and 7.0 (95% CI, 4.8–10.1) were noted for males and females, respectively, during the first 6 months of diagnosis when compared to those not diagnosed. The association between sleep disorders and suicide remained significant when adjusting for psychiatric disorders, although those with psychiatric disorders also had elevated rates, particularly amongst females. Conclusion In this study, individuals with sleep disorders had an increased suicide rate when compared to those with no sleep disorders. Higher suicide rates were found for individuals suffering from narcolepsy, insomnia and sleep apnea. More attention towards risks of suicide among people with sleep disorders might be needed. Support (if any):