Insomnia symptoms and the risk of all-cause mortality among stroke survivors

Abstract

Abstract Background Insomnia is more frequently reported in stroke survivors but its independent role in mortality in stroke survivors is unknown. The purpose of this study was to investigate the association of insomnia symptoms with all-cause mortality among stroke survivors. Methods The Health and Retirement Study, a survey of Americans older than 50 years and their spouses of any age from 2002 to 2018 was used. Only participants with a history of stroke were included. The exposure variable of interest was insomnia symptoms including difficulty initiating sleep, difficulty maintaining sleep, waking up too early, and nonrestorative sleep. The outcome was all-cause mortality. Cox proportional hazards regression models were employed to investigate the association between insomnia symptoms and all-cause mortality. Results A total of 3,501 stroke survivors were included of which 55% were females. Over a mean follow-up of 6 years, 1,782 deaths occurred. Difficulty initiating sleep (HR = 1.87, 95% CI: 1.07, 3.25) and difficulty maintaining sleep (1.89, 95% CI: 1.09, 3.29) were associated with all-cause mortality only among male stroke survivors younger than 65 years old while nonrestorative sleep (HR = 1.31, 95% CI: 1.05, 1.62) was associated with all-cause mortality only among male stroke survivors aged 65 years and older. Furthermore, male stroke survivors younger than 65 years of age and older than 65 with insomnia symptom scores ranging from 5 to 8 (mean = 6.2) had a higher but statistically nonsignificant risk of all-cause mortality (HR = 1.56, 95% CI: 0.81, 3.01 and HR = 1.08 95% CI: 0.85, 1.38, respectively) compared to their counterparts without insomnia symptoms. There was no association between insomnia symptoms and all-cause mortality among female stroke survivors. Conclusion Insomnia symptoms were associated with an increased risk of death especially in male stroke survivors younger than 65 years of age. Future studies should explore the benefit of insomnia symptom management in stroke survivors.

Keywords

• Stroke survivors
• All-cause mortality
• Insomnia symptoms
• Age difference
• Sex difference