Relationship of hearing impairment, social participation and depressive symptoms to the incidence of frailty in a community cohort

Background: The mediating effect of social participation and depressive symptoms on the relationship between hearing impairment and frailty remains unclear. Methods: A total of 3981 participants from three waves of the China Health and Retirement Longitudinal Study (CHARLS) were included. The outcome was incidental frailty. Hearing impairment, social participation, and depressive symptoms were the main variables. Cox regression models and structural equation models were adopted to examine the relationship between hearing impairment, social participation, depressive symptoms, and the incidence of frailty, with adjustments for demographic characteristics and lifestyle variables at baseline. Results: Hearing impairment (hazard ratio [HR] 1.31, 95% confidence interval [CI] 1.12, 1.74), social participation (HR 0.72, 95% CI 0.55, 0.94), and depressive symptoms (HR 1.78, 95% CI 1.37, 2.30) were associated with the incidence of frailty. Hearing impairment was associated with frailty not only through social participation (beta = 0.015, 95% CI 0.003, 0.037) and depressive symptoms (beta = 0.070, 95% CI 0.037, 0.116) separately but also through social participation and depressive symptoms sequentially (beta = 0.002, 95% CI 0.001, 0.004). Furthermore, the effect of social participation on frailty occurred in participants with hearing impairment, while the effect of depressive symptoms on frailty occurred in participants with normal hearing status. Conclusions: Hearing impairment is associated with frailty, in which social participation and depressive symptoms partly mediate the association. The effect of social participation and depressive symptoms on frailty varies across hearing statuses. Integrated and comprehensive intervention measures, including hearing screenings, promoting social participation, and improving depressive symptoms, are suggested to prevent frailty.