Association Between Internet Use and Sleep Health Among Middle-Aged and Older Chinese Individuals: Nationwide Longitudinal Study

Background Sleep disorders are common among older adults and have a bidirectional impact on their emotional well-being. While some studies suggest that internet use may offer mental health benefits to this population, the relationship between internet use and sleep outcomes remains underexplored. Objective This study investigates the association between internet use (including use frequency) and sleep quality and duration in middle-aged and older Chinese adults. Methods A longitudinal analysis was conducted using the China Health and Retirement Longitudinal Study data from 2015 to 2018. Sleep quality was assessed using the sleep item from the Centre for Epidemiologic Studies Depression Scale, categorized as “good” (<1 day; reference), “fair” (1-4 days), or “poor” (5-7 days). Sleep duration was classified as short (<6 hours), medium (6-9 hours; reference), or long (>9 hours). Adjusted multinomial logistic regressions were used to examine the associations between internet use or frequency in 2015 and sleep quality or duration in 2018, controlling for age, sex, residence, diseases, smoking, drinking, and napping time and further exploring sex and age group variations. Results The baseline analysis included 18,460 participants aged 45 years and older, with 1272 (6.9%) internet users, 8825 (48.1%) participants had fair or poor sleep, and 6750 (37.2%) participants had abnormal sleep duration. Internet users, particularly those who used it almost daily, were less likely to report poor sleep quality (relative risk [RR] 0.71, 95% CI 0.54-0.94) and longer sleep duration (RR 0.22, 95% CI 0.11-0.44) than nonusers. In the longitudinal analysis, baseline internet users had a significantly reduced risk of fair (RR 0.66, 95% CI 0.51-0.86) and poor sleep quality (RR 0.60, 95% CI 0.44-0.81), as well as short (RR 0.73, 95% CI 0.53-1.00) and long sleep duration (RR 0.39, 95% CI 0.21-0.72) during the follow-up period than nonusers. These associations remained significant for almost daily internet use (RR 0.32, 95% CI 0.15-0.69). Subgroup analyses by sex revealed a positive relationship between internet use and sleep quality, with a stronger effect in female (poor sleep: RR 0.57, 95% CI 0.36-0.89) than male (poor sleep: RR 0.61, 95% CI 0.40-0.92) participants. The effect on sleep duration was significant only in daily male users, showing a reduced risk of long sleep duration (RR 0.30, 95% CI 0.11-0.78). In the age subgroup analysis, most internet users were in the 45- to 59-year age group, with results consistent with the overall findings. Conclusions This study suggests that internet use is associated with a reduced risk of sleep problems in middle-aged and older adults. The findings indicate that moderate, regular internet engagement—such as daily use—may promote better sleep health in this population.