Longitudinal associations between social relationships and cognitive function among Chinese older adults: The mediating role of healthy lifestyles

Background: We aimed to explore whether social relationships and cognitive function were reciprocally related and whether healthy lifestyles mediate their association. Methods: This study included 3372 Chinese adults from the years 2014–2018 wave of the Chinese Longitudinal Healthy Longevity Survey. Results: Baseline social relationships were negatively associated with a change in cognitive function (β = –0.030, p = 0.043). Participants with a 1 standard deviation (SD) increase in social relationships had an approximately 6% reduced risk of developing cognitive impairment. However, baseline cognitive function did not independently predict social relationships. The association between △social relationships and △cognitive function was partially mediated by △a healthy lifestyle (B = 0.025, 95% CI = 0.013–0.041). Conclusions: The association between social relationships and cognitive function may be unidirectional. Policies that promote cognitive function based on social relationships would benefit by taking into account lifestyle factors.