Effects of different sizes of ambient particulate matter and household fuel use on physical function: National cohort study in China.

BACKGROUND: Impact of outdoor and household air pollution on physical function remains unelucidated. This study examined the influence of various ambient particulate sizes (PM1 , PM2.5 , and PM10 ) and household fuel usage on physical function.

METHODS: Data from the China Health and Retirement Longitudinal Study (CHARLS) spanning 2011 and 2015 were utilized. The physical functional score was computed by summing scores from four tests: grip strength, gait speed, chair stand test, and balance. Multivariate linear and linear mixed-effects models were used to explore the separate and combined effects of PM1 , PM2.5 , PM10 and household fuel use on physical function in the cross-sectional and longitudinal analyses, respectively, and to further observe the effects of fuel cleanup on physical function in the context of air pollution exposure.

RESULTS: Both cross-sectional and longitudinal analyses revealed negative correlations between PM1 (β = -0.044; 95% CI: -0.084, -0.004), PM2.5 (β = -0.024; 95% CI: -0.046, -0.001), PM10 (β = -0.041; 95% CI: -0.054, -0.029), and physical function, with a more pronounced impact observed for fine particulate matter (PM1 ). Cleaner fuel use was associated with enhanced physical function compared to solid fuels (β = 0.143; 95% CI: 0.070, 0.216). The presence of air pollutants and use of solid fuels had a negative impact on physical function, while cleaner fuel usage mitigated the adverse effects of air pollutants, particularly in areas with high exposure.

CONCLUSION: This study underscores the singular and combined detrimental effects of air pollutants and solid fuel usage on physical function. Addressing fine particulate matter, specifically PM1 , and prioritizing efforts to improve household fuel cleanliness in regions with elevated air pollution levels are crucial for preventing physical disability.