Particulate matter (PM) is known to increase the risk of cardiovascular disease (CVD). However, the association between short-term PM exposure and CVD incidence among older adults remains unclear. We aimed to assess the impact of PM2.5 and PMcoarse on CVD risk and its specific types, including overall CVD, coronary heart disease, acute myocardial infarction, ischemic stroke, and hemorrhagic stroke.
We recruited 471,706 patients aged 65 years and older who were newly diagnosed with CVD between 2015 and 2021, using data from the National Health Insurance Service (NHIS) database in South Korea. PM concentrations, specifically those with diameters smaller than 2.5 μm (PM2.5) and 10 μm (PM10), were obtained from the National Ambient Air Monitoring System. The concentration of PMcoarse was calculated by subtracting PM2.5 from PM10. A time-stratified case-crossover design was applied to estimate adjusted odds ratios (aORs) and 95% confidence intervals (CIs) for CVD using conditional logistic regression.
Compared to the lowest quartile of PM2.5, the highest quartile of lag0 (aOR 1.04, 95% CI 1.02–1.05) and lag0-1 (aOR 1.03, 95% CI 1.02–1.04) had higher CVD risk. Similarly, the 4th quartile of lag0 (aOR 1.03, 95% CI 1.02–1.04) and lag0-1 (aOR 1.02, 95% CI 1.01–1.03) had higher odds for CVD compared to the 1st quartile of PMcoarse. The highest quartile of lag0-1 for PM2.5 (aOR 1.04, 95% CI 1.02–1.06) and PMcoarse (aOR 1.02, 95% CI 1.00–1.04) showed increased odds of coronary heart disease. For stroke, however, a significant increase in CVD risk was observed only for ischemic stroke, not hemorrhagic stroke.
We found a significant dose-response relationship indicating that higher levels of short-term PM exposure were associated with an increased risk of CVD among older adults. Systematic management of short-term exposure to PM in older adults may reduce the risk of future CVD occurrence.