To explore the relationship between sleep duration, its changes, and the activities of daily living (ADL) in the elderly.

Utilizing data from the China Health and Retirement Longitudinal Study, participants who took part in the surveys conducted in 2018 and 2020 were selected. Based on sleep duration, participants were categorized into three groups: short sleep (<7 hours), adequate sleep (7-9 hours), and long sleep (>9 hours). The study employed restricted cubic spline analysis to examine the dose-response relationship between sleep duration and ADL, and a Cox proportional hazards regression model to analyze the relationship between dynamic changes in sleep duration and ADL.

A total of 3 923 participants were included in this study, with 1 162 (29.6%) experiencing ADL impairment during the follow-up period. The Cox proportional hazards regression model indicated that individuals who consistently maintained short sleep and those who transitioned from adequate sleep to short sleep had a 50% and 39% increased risk of ADL impairment, respectively, with hazard ratios (HR) and 95% confidence intervals (CI) of 1.50(1.27-1.78) and 1.39 (1.14-1.71). Additionally, those with a significant reduction in sleep duration (< -2 hours) had a 20% increased risk of ADL impairment (HR=1.20, 95%CI: 1.01-1.41).

Maintaining adequate and stable sleep duration over the long term can reduce the risk of ADL impairment in the elderly.