Insomnia symptoms and increased risk of all-cause mortality by age and sex.

Study objectives: Prior research suggests that insomnia may increase the risk of death. However, the potential influence of age and sex is unclear. This study aimed to investigate the association of insomnia symptoms with all-cause mortality by age and sex.

Methods: This prospective cohort was drawn from the Health and Retirement Study, a survey of Americans older than 50 years and their spouses of any age from 2002-2018. Insomnia symptom scores were based on difficulties initiating sleep, difficulty maintaining sleep, waking up too early, and nonrestorative sleep. Cox proportional-hazards regression models were employed to investigate the association between insomnia symptoms and all-cause mortality stratified by age and sex.

Results: A total of 33,004 participants were included with a mean age of 61.7 years and 56.8% females. Over a mean follow-up of 8.4 years, 8,935 (27.1%) deaths were recorded. After adjusting for confounding, males with insomnia symptom scores ranging from 5-8 had a 71% increased risk of death (hazard ratio = 1.71; 95% confidence interval: 1.27, 2.30) compared with their counterparts without insomnia symptoms. Similarly, males aged ≥ 60 years and females aged < 60 years with insomnia symptoms ranging from 5-8 had an increased risk of death compared with their counterparts without insomnia symptoms (hazard ratio = 1.15; 95% confidence interval: 1.02, 1.31 and hazard ratio = 1.38; 95% confidence interval: 1.00, 1.90, respectively). However, there was no increased risk of death for females aged ≥ 60 years (hazard ratio = 0.94; 95% confidence interval: 0.84, 1.06).

Conclusions: These findings suggest that insomnia symptoms may serve as predictors of low life expectancy.

Citation: Sawadogo W, Adera T. Insomnia symptoms and increased risk of all-cause mortality by age and sex. J Clin Sleep Med. 2024;20(10):1585-1593.