Healthy Lifestyle Mitigates the Adverse Association of Particulate Matter with Cognitive Function: A 10-year Longitudinal Analysis of Older Adults in China

Abstract

Background Both air pollution and lifestyle are associated with cognitive function, with air pollution being detrimental and positive lifestyles being beneficial. The extent to which a favorable lifestyle can mitigate the harmful effects of air pollution on cognitive function in later life warrants further investigation. Methods 7,651 individuals aged 65 years and above from the Chinese Longitudinal Healthy Longevity Survey (CLHLS) were followed up between 2008 and 2018. Cognitive function was measured at each wave using the Mini-Mental State Examination (MMSE). Particulate matter (PM1, PM2.5, and PM10) concentrations were assessed using satellite-based spatiotemporal models. A favorable lifestyle was determined based on four lifestyle factors: never drinking, never smoking, regular exercise, and a healthy diet. Linear mixed-effects models were employed to estimate the association between PM and cognitive function as well as potential mitigation by lifestyle. Results Overall, there were significant associations between PM and cognitive function, with MMSE scores decreasing by 0.47 points (95% confidence interval (CI): -0.62, -0.33), 0.66 points (95% CI: -0.83, -0.49), and 0.62 points (95% CI: -0.78, -0.46) per IQR increase in PM1, PM2.5, and PM10, respectively. A favorable lifestyle was beneficial for cognitive function. Moreover, the adverse association between PM exposure and cognitive function was significantly attenuated by a favorable lifestyle (p-interaction = 0.007, 0.013, 0.037 for PM1, PM2.5, and PM10, respectively). Conclusions A favorable lifestyle may mitigate the adverse association between PM exposure and cognitive function. Lifestyle interventions could be beneficial in counteracting the neurological impacts of ambient air pollution.