Effects of fine particulate matter air pollution on cardiovascular mortality in Dhaka, Bangladesh, from 2020 to 2024.

Abstract

Introduction: Although air pollution is a leading cause of mortality in Bangladesh, epidemiological studies remain limited and largely focus on exposure rather than health outcomes. Therefore, we investigated the effects of fine particulate matter (PM_2.5) exposure on Cardiovascular Disease (CVD) mortality in Dhaka city.

Methods: We collected monthly CVD mortality records from four major government medical college hospitals in Dhaka city between 2020 and 2024. We obtained corresponding PM_2.5 concentrations from the Department of Environment and meteorological data from NASA POWER project. We applied a Generalized Additive Model (GAM) with a quasi-Poisson distribution and incorporated lag structures to estimate the percentage change in CVD mortality per 10 µg/m³ increase in PM_2.5 concentration.

Results: We found a total of 17,531 CVD deaths during the study period. A 10 µg/m³ increase in PM_2.5 concentration was associated with a 3.1 % increase in CVD mortality at lag 0 (95 % CI: 1.1 % , 5.2 %). Furthermore, an estimated 16 % of total CVD deaths during the study period were attributable to PM_2.5 exposure. Seasonal analysis showed that 28.7 % of CVD deaths in cold months were attributable to PM_2.5, compared to only 7.15 % during the hot months. The exposure-response relationship was non-linear and showed a gradual increase in CVD mortality, indicating higher health risks at high levels of PM_2.5.

Conclusion: Our study provides clear evidence that elevated PM_2.5 concentrations significantly contribute to cardiovascular mortality in Dhaka city. Therefore, reducing PM_2.5 through urgent and sustained policy action, targeted emission control, and improved monitoring could substantially lower CVD mortality and mitigate the growing health impacts of air pollution in urban Bangladesh.