Reduced social activities and networks, but not social support, are associated with cognitive decline among older chinese adults: A prospective study

Social relationships consist of distinct dimensions. The literature on the effect of specific social relationship subdomains on cognitive function is limited. This large-scale, prospective cohort study examined the associations of social relationships with cognitive decline and further explored which subdomains of social relationships were predictive of cognitive decline among elderly Chinese individuals. A total of 3314 older Chinese adults aged 65–110 years from the 2011–2012 wave of the Chinese Longitudinal Healthy Longevity Survey (CLHLS) were included. Cognitive decline was defined based on the Chinese version of the Mini-Mental State Examination (MMSE). Social relationships were divided into three subdomains: social activities, social networks, and social support. Linear and binary logistic regression analyses were conducted to assess the effect of social relationships and the social relationship subdomains on cognitive decline after adjusting for age, sex, education, residence, exercise, drinking, smoking, activities of daily living, chronic diseases, depression, and baseline cognitive function. Seven hundred and sixty-eight participants (23.17%) developed greater cognitive decline during the 3-year follow-up. The social relationships score was negatively associated with cognitive decline. Binary adjusted odds ratios showed that after potential covariates were controlled, social relationships, activities, and networks significantly reduced the risk of cognitive decline. When all social relationships variables were entered simultaneously with all covariates, the effect of social activities and networks on the risk of greater cognitive decline remained significant. However, we did not observe a significant association between social support and the risk of greater cognitive decline. Our findings suggest that social relationships and the subdomains of social activities and networks, but not social support, have a protective effect against greater cognitive decline in older adults. This implies that structural dimensions of social relationships might be more important than functional dimensions in preserving cognitive health among elderly Chinese individuals.