The association between health-related factors, physical and mental diseases, social activities, and cognitive function in elderly Koreans: a population-based cross-sectional study

Aim The purpose of this study was to verify the association of cognitive function with health-related variables, diseases, and social activities. Methods Data from the 2016 Korean Longitudinal Study of Aging were analyzed. The participants of that study were 5678 adults aged 60 years or older living in 17 major Korean regions nationwide. Results Hierarchical multiple regression analyses indicated that gender, age, education, marital status, depressive symptoms, body mass index, regular exercise, activities of daily living, instrumental activities of daily living, hand grip strength, and social activities were all significantly associated with cognitive function in elderly Koreans. However, socioeconomic status, diabetes, smoking, alcohol consumption, attendance at school reunions, volunteer work, and participation in political or civic organizations had no impact on cognitive function. First, the results indicated that men had better cognitive function than women; likewise, married individuals and those with a higher level of education also had better cognitive function. As age increased, cognitive function declined. Second, higher body mass index was related to poorer cognitive function, whereas regular exercise was positively associated with better cognitive function. In addition, higher activities of daily living and instrumental activities of daily living scores were associated with poorer cognitive function. Third, depressive symptoms were negatively associated with cognitive function. Finally, religious activities, social activities, and participation in leisure activities, cultural events, and sports were associated with better cognitive functioning. The possibility of reverse association exists between some of the variables (e.g. religious activity and cognitive function), and it is necessary to verify this possibility through a longitudinal study. The biggest limitation is that this is a cross-sectional study, which made it unfeasible to investigate the causal pathways. Conclusions This study suggests that regularly exercising and attending social activities each help to improve cognitive function in the elderly.