Short-, Mid-, and Long-Term Associations Between PM2.5 and Stroke Incidence in Taiwan

Objective: To investigate the association between the risk of stroke and exposure to particulate matter with an aerodynamic diameter less than 2.5 μm (PM 2.5 ) over various exposure periods. Methods: This was a nationwide population-based case–control study in which 10,035 incident patients with a primary diagnosis of ischemic stroke each were matched with two randomly selected controls for sex, age, Charlson Comorbidity Index, year of stroke diagnosis, and level of urbanization. Multiple logistic models adjusted for potential confounders were used to assess the association of PM 2.5 with ischemic stroke incidence. Results: There were significant short-term, medium-term, and long-term relationships between PM 2.5 exposure and ischemic stroke incidence. Conclusions: This study supports existing evidence that PM 2.5 should be considered a risk factor for ischemic stroke.