Association between hearing aid use and cognitive function among Chinese middle-aged and older adults with hearing impairment: the mediating effect of social activity

Background: In China's ageing population, hearing-impaired middle-aged and older adults face cognitive vulnerability. We aimed to explore the effects of hearing aid use on cognitive function and to examine the mediating role of social activity in this relationship. Methods: We sourced data from the China Health and Retirement Longitudinal Study for the years 2011, 2013, 2015, 2018, and 2020. Using multiple linear regression and binary logistic regression, we analysed the association between hearing aid use and cognitive scores, as well as the risk of cognitive impairment in middle-aged and older adults with hearing impairments. PROCESS models explored whether social activities mediated the relationship between hearing aid use and cognitive function. Results: Hearing aid use was significantly positively associated with cognitive performance among middle-aged and older adults with hearing impairment (coefficient = 1.226). Hearing aid use was also significantly associated with a 29.6% lower risk of cognitive impairment compared with nonusers within this population (odds ratio = 0.704). Moreover, hearing aid use was associated with higher cognitive scores and a reduced risk of cognitive impairment, linked to increased participation in social activities, particularly intellectual and physical pursuits. Finally, the direct associations between hearing aid use and cognitive function, and the mediating role of social activities in this relationship, varied by gender and age. Conclusions: Promoting hearing aid use and social activity is vital to improve cognitive function and reduce impairment risk in middle-aged and older adults with hearing loss. Tailored interventions should address gender- and age-related differences to maximise benefits.