Specific activities and the trajectories of cognitive decline among middle-aged and older adults: A five-year longitudinal cohort study

Background: How specific activities influence cognitive decline among different age groups, especially the late middle-aged and the early old, remains inadequately studied. Objective: To examine the association between specific activities with trajectories of cognitive functions in different age groups in China. Methods: A longitudinal cohort study was conducted based on data from the China Health and Retirement Longitudinal Study (CHARLS). Mixed effects growth models were applied to analyze the association between specific activities and cognitive functions. Results: Interacting with friends (infrequent: β= 0.13, confidence interval [CI] = 0.03 to 0.22; daily: β= 0.19, CI = 0.09 to 0.28), playing Mah-jong or other games (infrequent: β= 0.12, CI = 0.02 to 0.22; daily:β= 0.26, CI = 0.10 to 0.42), infrequent providing help to others (β= 0.24, CI = 0.11 to 0.37), and going to a sport (infrequent: β= 0.31, CI = 0.08 to 0.54); daily: β= 0.22, CI = 0.05 to 0.38) are significantly associated with participants' memory. Infrequently playing Mah-jong or other games (β= 0.30, CI = 0.17 to 0.43) and daily sports (β= 0.24, CI = 0.03 to 0.45) are significantly associated with better mental status. Effect of each activity varies among population of different age, education level, gender, and residence. Conclusion: This study identifies four social activities that are associated with better cognitive functions, and provides a comprehensive, in-depth understanding on the specific protective effect of each activity among different subgroups.