Independent and joint associations of sleep and 24-Hour rest-activity rhythms with reduced kidney function in older...

This study aimed to investigate the independent and joint associations of sleep and 24-hour rest-activity rhythms with reduced kidney function among older adults in rural China.

Data from 1493 participants in the baseline survey of the Rural Physical Activity Behavior and Healthy Aging Cohort were analyzed. Sleep and 24-hour rest-activity rhythm parameters, including total sleep time (TST), wakefulness after sleep onset (WASO), interdaily stability (IS), intradaily variability (IV), Least active 5 h span (L5), Most active 10 h span (M10), and relative amplitude (RA). Multivariable logistic regression models were employed to examine the independent and joint associations of sleep and 24-hour rest-activity rhythms with reduced kidney function.

Independent analyses revealed that IS, L5, and M10 were significantly inversely associated with reduced kidney function (IS: OR = 0.13, 95% CI: 0.04-0.49; L5: OR = 0.89, 95% CI: 0.82-0.97; M10: OR = 0.97, 95% CI: 0.96-0.99), whereas IV and TST were significantly positively associated with reduced kidney function (IV: OR = 2.90, 95% CI: 1.37-6.15; TST: OR = 1.35, 95% CI: 1.15-1.57). Joint analyses demonstrated that compared with the long sleep group, the moderate and short sleep groups exhibited significantly lower ORs. Regardless of sleep duration, the stable rest-activity rhythm group showed significantly lower ORs than the unstable group.

These findings suggest that maintaining stability in rest-activity rhythms should be emphasized in older rural Chinese populations, as it may play an important role in the early prevention and management of reduced kidney function.