BACKGROUND: Cognitive frailty, encompassing cognitive decline and physical frailty, is an increasing concern in aging populations. Air pollution is associated to several health outcomes. METHODS: This study aims to investigate the potential association between air pollution and cognitive frailty in aging populations. Data of 62,098 participants from UK Biobank cohort and 3,321 participants from West China Health and Aging Trend (WCHAT) cohort were subjected to cross-sectional analyses to evaluate the association between the investigating parameters, and prospective analyses were performed in the UK Biobank. Air pollution exposure was estimated over multiple time periods, adjusting for demographic, socioeconomic, and health-related factors. RESULTS: Exposure to ambient air pollution was significantly associated with increased risk of cognitive frailty in middle-aged and older adults. In the UK Biobank prospective analysis, exposures to NOx (hazard ratio HR 1.11, 95% confidence interval CI 1.01-1.23; p = 0.0357), nitrogen dioxide (HR 1.14, 95% CI, 1.00-1.30; p = 0.0428), and PM2.5 (HR 1.18, 95% CI, 1.04-1.34; p = 0.0091) were consistently associated with cognitive frailty. Cross-sectional analyses in the UK Biobank supported these findings, with additional positive associations observed for PM10 (OR 1.02, 95% CI, 1.00-1.05; p = 0.0374). In WCHAT cohort, ozone exposure showed the most consistent associations across exposure windows and models (3-year: OR 1.29, 95% CI, 1.14-1.45; p < 0.0001; 5-year: OR 1.34, 95% CI, 1.20-1.50; p < 0.0001). Additionally, PM2.5 exposure within the 1-year exposure window also demonstrated a statistically significant association (Q3: OR 1.53, 95% CI, 1.04-2.25; p = 0.0327). Stratified analyses suggested stronger associations among adults ≥60 years, females, and overweight individuals. CONCLUSION: Higher air pollution levels were significantly associated with increased cognitive frailty risk, emphasizing on developing public health interventions to reduce air pollution exposure, especially among vulnerable populations.
Deng et al. (2026) studied this question.