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

Impact of outdoor and household air pollution on physical function remains unelucidated. This study examined the influence of various ambient particulate sizes (PM₁, PM_2.5, and PM₁₀) and household fuel usage on physical function.

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, PM_2.5, 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.

Both cross-sectional and longitudinal analyses revealed negative correlations between PM₁ (β = -0.044; 95% CI: -0.084, -0.004), PM_2.5 (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.

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.