Global Disease Burden Attributable to Ambient Air Pollution: Disparities, Determinants, and Implications for Public Health

Background: Ambient air pollution is a leading environmental risk factor for premature mortality worldwide. Characterizing the associated disease burden and spatiotemporal patterns is essential for informing global health policy. Methods: Using data from the Global Burden of Disease Study 2021, we assessed temporal trends and spatial heterogeneity in disease burden attributable to ambient fine particulate matter (PM 2.5 ) and ozone (O 3 ) during 1990–2020. We further examined the association between sociodemographic index (SDI) and disease burden, and conducted decomposition analysis to quantify the driving factors of temporal changes in disease burden. Results: From 1990 to 2020, the age-standardized death rates attributable to ambient PM 2.5 and O 3 both declined globally, but substantial regional heterogeneity was observed. High-SDI regions generally experienced declining burdens, whereas low- and middle-SDI regions showed persistent or increasing trends. A significant reversed U-shaped association between SDI and both PM 2.5 - and O 3 -attributable burden was observed, consistent with an environmental Kuznets-type pattern. Despite the decline in age-standardized rates, the absolute number of deaths attributable to ambient PM 2.5 and O 3 both increased, driven primarily by population aging, population growth, and increasing exposure levels, although reductions in baseline mortality rates partly offset these increases. Conclusions: Ambient air pollution continues to contribute to substantial and persistent disparities in global disease burden. Health-oriented and region-specific air pollution control strategies are needed to effectively mitigate these inequities and improve population health.