The impact of sensory impairments and eye diseases on cognitive function in elderly Chinese: The mediating effects of social participation

BACKGROUND: Sensory impairments and eye diseases increase the risk of cognitive decline, but little is known regarding their influence on cognitive function in elderly Chinese and the underlying mechanisms. We aimed to explore these influence mechanism from the social participation perspective. METHODS: We selected 2876 respondents aged ≥60 from the China Health and Retirement Longitudinal Study (CHARLS) conducted in 2013, 2015, and 2018. We assessed sensory impairments and eye diseases based on self-reported responses, and evaluated its relation to social participation and cognitive function by fixed-effects regression and mediation effect analysis over a five-year period. RESULTS: Respondents with visual impairment and cataracts had poor memory and mental status. Compared with near visual impairment, distance visual impairment was associated with a 1.7 times higher likelihood of cognitive decline (correlation coefficient (β) = -0.051; 95% confidence interval (CI) = -0.065, -0.036)). Respondents with hearing impairment had bad memory (β = -0.046; 95% CI = -0.065, -0.036), but not mental status. Social participation partially mediated the relationships of sensory impairments and cataracts with cognitive function in elderly Chinese. Individuals with sensory impairments affected by limited social participation reported a faster cognitive decline compared to those with eye disease. CONCLUSIONS: We found that sensory impairments and eye diseases were negatively associated with cognitive function. Furthermore, sensory impairments and cataracts influence cognitive function partly via social participation. Our results have important theoretical and practical implications and suggests that early interventions for sensory impairments and eye diseases may improve the cognitive function of elderly people.