Association of physical activity levels with frailty index in elderly Chinese: evidence from the China health and retirement longitudinal study (CHARLS)
Qianqian Li, Jiayi Guan, Ronghui Wang
Abstract
As the global trend of population aging intensifies, frailty among the elderly has emerged as a significant public Health concern. This study examines the relationship between physical activity levels and the Frailty Index in older adults, utilizing data from the 2018 China Health and Retirement Longitudinal Study (CHARLS). The study sample included 10,240 Chinese adults aged ≥ 60 years.Frailty was assessed using the Frailty Index (FI), which was calculated based on the accumulation of age-related health deficits. The level of physical activity were determined using the International Physical Activity Questionnaire (IPAQ) and expressed in terms of metabolic equivalent (MET) units. The dose-response relationship between physical activity and the Frailty Index was examined using restricted cubic splines (RCS) and logistic regression analysis. The results demonstrated a significant inverse relationship between physical activity level and the risk of frailty. Specifically, participants in the highest quartile of physical activity had a 45% lower risk of frailty compared to those in the lowest quartile (OR = 0.55, 95% CI: 0.48–0.63). The protective effect of physical activity remained robust across various models, even after adjusting for potential confounders, such as age, sex, education level, marital status, and health behaviors. The RCS model revealed a nonlinear relationship between physical activity and frailty risk, higher levels of physical activity significantly reduce the risk of frailty in the elderly, with moderate-to high-intensity physical activity playing a crucial role in decreasing the prevalence of frailty. However, further increase in activity beyond a certain point may not yield additional benefits.