Longitudinal relationship between sensory impairments and depressive symptoms in older adults: The mediating role of functional limitation.

BACKGROUND: The underlying mechanism between sensory impairments (SIs) and depressive symptoms among Chinese older adults is not well understood. This study aims to explore the mediating role of functional limitation on the longitudinal relationship between SIs and depressive symptoms among older adults in China.

METHODS: A total of 4130 older adults who participated in the 3-year follow-up China Health and Retirement Longitudinal Study (CHARLS) were included in the analysis. The hierarchical multiple linear regression model and nonparametric bootstrapping method were employed to explore the relationship between SIs and depressive symptoms, and the mediating role of functional limitation in this link.

RESULTS: The prevalence of self-reported hearing impairment (HI) only, vision impairment (VI) only, and dual sensory impairment (DSI) at baseline were 5.7%, 22.2%, and 58.6%, respectively. After adjusting for controlling variables, older adults with DSI had significantly higher levels of depressive symptoms compared with those without SIs at baseline (β = .07, p = .005). The magnitude of mediation effect from DSI to depressive symptoms via functional limitation was a*b = 0.060 (BCa 95% confidence interval: 0.031-0.094).

CONCLUSIONS: Functional limitation partially mediated the relationship between DSI and depressive symptoms among Chinese older adults. Interventions of DSI and functional limitation should be included in depressive symptoms prevention among older adults in China.