Impact of air pollution and behavioral factors on cognitive decline among middle-aged and elderly populations in China: a retrospective cohort study based on CHARLS.

This retrospective cohort study was based on the China Health and Retirement Longitudinal Study (CHARLS) database, utilizing longitudinal data collected from 2011 to 2018 and comprising 65,159 person-wave observations from 23,412 unique participants, combined with a high-resolution air pollution model, to systematically assess the impact of multidimensional factors (sociodemographic characteristics, lifestyle, health status, and air pollution) on cognitive decline in middle-aged and elderly individuals. The study revealed that age is the primary factor affecting cognitive function, which decreases with increasing age. Through stratified regression and interaction tests, factors significantly affecting cognitive decline were identified and ranked according to importance via a random forest model. The results indicated that PM was the most significant factor affecting cognitive decline, regardless of sex, followed by fuel type usage, BMI, and physical activity, among other factors. This study comprehensively integrated the effects of air pollution and multidimensional factors on cognitive decline, providing a scientific basis for developing gender-specific and personalized cognitive intervention strategies.