Global burden of ischemic heart disease attributable to ambient and household PM_2.5 exposure: a comprehensive analysis (1990–2021) from socioeconomics perspective

Objectives: Socioeconomic status links to exposure of air pollutants. This study evaluates global PM_2.5-attributable ischemic heart disease (IHD) burden from 1990 to 2021. Methods: Using Global Burden of Disease (GBD) 2021 data, PM_2.5-related IHD burdens were analyzed. Joinpoint regression identified annual percentage changes (AAPCs); Pearson correlation assessed associations with Socio-demographic Index (SDI); Slope Index of Inequality (SII) and Concentration Index (CI) were applied to quantify inequality; Frontier analysis was conducted to evaluate the efficiency of health outcomes relative to development level; Decomposition analysis was performed to identify key drivers of burden changes over time. Results: From 1990 to 2021, age-standardized rates (ASMR, ASDR) of IHD attributable to ambient PM_2.5 declined to 20.85 per 100,000 (AAPC = −0.7), with attributable to household PM_2.5 decreased to 9.02 per 100,000 (AAPC = −2.49). Middle-low SDI regions exhibited the highest increases in ambient PM_2.5-related burden, whereas high SDI regions showed marked declines (AAPC = −4.31). All regions showed downward in household PM_2.5-attributable ASMR and ASDR. Disease burden was disproportionately higher among males and older populations. ASMR and ASDR of IHD exhibited a nonlinear association with SDI. PM_2.5 demonstrated positive correlation in regions with SDI < 0.49, and negative correlation in regions with SDI > 0.623. SII and CI indicated rising inequality in ambient PM_2.5-related burden. Frontier analysis revealed efficiency gaps in low-SDI regions. Decomposition highlighted population aging and ambient PM_2.5 exposure as major drivers of burden trends. Conclusion: Ambient pollution burdens increase in middle-SDI and household pollution impacts focus on low-SDI, which needs prioritizing clean energy and protecting high-risk populations.