Associations of sensory impairment and cognitive function in middle-aged and older Chinese population: The China Health and Retirement Longitudinal Study

BACKGROUND: Little is known about the associations between vision impairment, hearing impairment, and cognitive function. The aim of this study was to examine whether vision and hearing impairment were associated with a high risk for cognitive impairment in middle-aged and older Chinese adults. METHODS: A total of 13 914 Chinese adults from the China Health and Retirement Longitudinal Study (CHARLS) baseline were selected for analysis. Sensory impairment was assessed from a single self-report question, and we categorized sensory impairment into four groups: no sensory impairment, vision impairment, hearing impairment, and dual sensory impairment. Cognitive assessment covered memory, mental state, and cognition, and the data was obtained through a questionnaire. RESULTS: Memory was negatively associated with hearing impairment (β = -0.043, 95% confidence interval (CI) = -0.076, -0.043) and dual sensory impairment (β = -0.033, 95% CI = -0.049, -0.017); mental status was negatively associated with vision impairment (β = -0.034, 95% CI = -0.049, -0.018), hearing impairment (β = -0.070, 95% CI = -0.086, -0.055), and dual sensory impairment (β = -0.054, 95% CI = -0.070, -0.039); and cognition was negatively associated with vision impairment (β = -0.028, 95% CI = -0.044, -0.013), hearing impairment (β = -0.074, 95% CI = -0.090, -0.059), and dual sensory impairment (β = -0.052, 95% CI = -0.067, -0.036), even after adjusting for demographics, social economic factors, and lifestyle behavior. CONCLUSIONS: Vision and hearing impairment are negatively associated with memory, mental status, and cognition for middle-aged and elderly Chinese adults. There were stronger negative associations between sensory impairment and cognitive-related indicators in the elderly compared to the middle-aged.