Global burden of cardiometabolic diseases attributable to ambient and household PM 2.5 exposure: an analysis based on the 1990-2021 global burden of disease study

Background Ambient and household fine particulate matter (PM2.5) exposure is a major modifiable risk factor for cardiometabolic diseases (CMDs). However, evidence on long-term trends, inequalities, and future burden remains limited.Objective To quantify the global burden of CMDs attributable to ambient and household PM2.5 exposure from 1990 to 2021 and project future burden through 2050.Methods: Using Global Burden of Disease (GBD) 2021 data from 204 countries and territories, we estimated PM2.5-attributable deaths and disability-adjusted life years (DALYs) for cardiovascular disease (CVD), ischemic heart disease (IHD), stroke, and type 2 diabetes mellitus (T2DM). Socioeconomic inequalities were assessed using the Slope Index of Inequality and Concentration Index. Decomposition analysis quantified the contributions of population growth, population ageing, and epidemiological change. Bayesian age-period-cohort models projected disease burden through 2050.Results From 1990 to 2021, the global burden of PM2.5-attributable CMDs increased substantially, with T2DM showing the largest relative increases (141% in deaths and 182% in DALYs). In 2021, PM2.5 exposure accounted for 4.48 million CVD deaths, with ambient PM2.5 contributing more than household PM2.5. The burden was highest among males, older adults, and populations in low-SDI regions. Absolute socioeconomic inequality in CVD mortality declined, whereas relative inequalities for IHD and T2DM increased. Projections suggested increasing CVD burden but declining T2DM burden through 2050.Conclusions Ambient and household PM2.5 exposure remains an important contributor to the global CMDs burden, with substantial geographic and socioeconomic disparities. This study provides epidemiological evidence on the long-term distribution and trends of PM2.5-attributable CMDs burden.