Hearing impairment and depression in middle-aged and older Chinese adults: the potential intermediary role of sleep duration in the CHARLS cohort

BACKGROUND: Hearing impairment has been associated with depressive symptoms in older adults. Sleep duration may represent a potential contributing factor linking these conditions. METHODS: We analyzed data from the China Health and Retirement Longitudinal Study (CHARLS, 2011–2015), including 12,934 participants aged ≥ 45 years. Hearing impairment was defined by self-report, depressive symptoms by CES-D10 ≥ 10, and sleep duration as average nightly sleep hours. Logistic regression models were used to estimate associations, adjusting for sociodemographic and health-related covariates. To explore whether sleep duration contributed to the observed association, we compared effect estimates before and after adjustment for sleep duration. RESULTS: Hearing impairment was associated with higher odds of depressive symptoms (OR = 1.83, 95% CI: 1.69–1.97). After further adjustment for sleep duration, the association was slightly attenuated (OR = 1.77, 95% CI: 1.63–1.91), suggesting that sleep duration may contribute modestly to the observed relationship. Stratified analyses showed similar patterns across subgroups. CONCLUSIONS: Self-reported hearing impairment is associated with depressive symptoms among middle-aged and older Chinese adults. Sleep duration may partially contribute to this association, although causal inference cannot be established.