Sleep Duration and Sleep Disturbances as Predictors of Healthy and Chronic Disease-Free Life Expectancy between Ages 50 and 75: A Pooled Analysis of Three Cohorts.

Background: The aim of this study was to examine the associations of sleep duration and sleep disturbances with healthy and chronic disease-free life expectancy (LE) between ages 50 and 75.

Methods: Data were drawn from repeated waves of three occupational cohort studies in England, Finland and Sweden (n=55,494) and the follow-up ranged from 6 to 18 years. Self-reported sleep duration was categorized into <7h, 7-8.5h and ≥9h and sleep disturbances into no, moderate, and severe. Health expectancy was estimated with two health indicators: healthy LE based on years in good self-rated health and chronic disease-free LE based on years without chronic diseases. Multistate life table models were used to estimate healthy and chronic disease-free LE from age 50 to 75 years for each category of sleep measures in each cohort. Fixed-effects meta-analysis was used to pool the cohort-specific results into summary estimates.

Results: Persons who slept 7-8.5 hours could expect to live 19.1 (95% CI 19.0-19.3) years in good health and 13.5 (95% CI 13.2-13.7) years without chronic diseases between ages 50 and 75. Healthy and disease-free years were 1-3 years shorter for those who slept less than 7 hours or slept 9 hours or more. Persons who did not have sleep disturbances could expect to live 20.4 (95% CI 20.3-20.6) years in good health and 14.3 (95% CI 14.1-14.5) years without chronic diseases between ages 50 and 75. Healthy and disease-free years were 6-3 years shorter for those who reported severe sleep disturbances.

Conclusions: Sleeping 7-8.5 hours and having no sleep disturbances between ages 50 to 75 are associated with longer healthy and chronic disease-free LE.