The association between PM_2.5 and frailty: evidence from 122 cities in China and 7 countries in Europe

The accelerated aging process worldwide is placing a heavy burden on countries. PM_2.5 particulate matter exposure is a significant factor affecting human health and is crucial in the aging process.

We utilized data from China Health and Retirement Longitudinal Study (CHARLS) and the Survey of Health, Aging, and Retirement in Europe (SHARE) to study the relationship between PM_2.5 exposure and the frailty index. Acquire PM_2.5 exposure data for China and Europe, match them according to geographic location within the database. Our study used frailty index to evaluate frailty, which comprises 29 items. We examined the association between PM_2.5 and frailty index using fixed-effects regression models and Mendelian randomization (MR) analysis.

We first examined the association between PM_2.5 and frailty index using fixed-effects regression models, revealing a notable positive link across populations in China (coefficient = 0.0003, P = 0.0380) and Europe (Coefficient = 0.0019, P < 0.0001). This suggests that PM_2.5 exposure is a significant risk factor for frailty, leading to accelerated frailty. Moreover, our MR analysis uncovered a possible causal association (OR = 1.2933, 95%CI: 1.2045–1.3820, P < 0.0001) between PM_2.5 exposure and the frailty index.

Our findings indicate that long-term exposure to PM_2.5 in the environment is a risk factor for physical frailty and may have a potential causal relationship. Given the rapid global aging trend, public health measures are needed to reduce PM_2.5 concentrations and prevent frailty.