Association between Physical Activity Changes Trajectories and Frailty in Older Adults

Background With the intensification of population aging in China, the issue of frailty among the elderly is becoming increasingly prominent, making research on its prevention and intervention particularly important. Currently, most studies lack discussion on the dynamic relationship between changes in physical activity and frailty. Objective This study is based on the five waves of data from the China Health and Retirement Longitudinal Study (CHARLS) from 2011 to 2020, aiming to explore the association between physical activity changes trajectories and frailty in older adults, and to provide a scientific basis for the prevention and intervention of frailty in the elderly. Methods Group-based trajectory modeling (GBTM) was used to identify the potential subgroups and trajectory characteristics of physical activity over time among the survey participants during the follow-up period. Multivariate unconditional logistic regression models were employed to analyze the association between different physical activity trajectory types and frailty, as well as subgroup analyses. Results The physical activity trajectories of the survey participants were divided into four groups: persistent low group (262 individuals, 13.87%), low-to-increasing group (993 individuals, 52.57%), high-to-decreasing group (122 individuals, 6.46%), and persistent high group (512 individuals, 27.10%). There were significant differences in frailty among the four groups (χ2=20.867, P