Short-term exposure to air pollution and risk of ischemic stroke requiring intravenous thrombolysis: a population-level analysis in Poland from the EP-PARTICLES study

Air pollution is an important non-classical cardiovascular risk factor. Ischemic stroke (IS) is an increasing healthcare challenge, with the ageing population and associated presence of atrial fibrillation worldwide. In patients with IS, intravenous thrombolysis (IVT) is an effective treatment method within 4.5 hours from symptoms onset. Our aim was to assess the association between exposure to air pollution and IVT-treated IS, allowing for high temporal precision in exposure assessment. We conducted a retrospective population-based cohort study including 5.4 million inhabitants in Eastern Poland in the Years 2011–20. IVT-treated IS patients were enrolled into this study based on ICD-10 and ICD-9 code (I63 with 99.101/99.102/99.103). To ensure high spatial resolution, we used the GEM-AQ model for air quality modeling. Generalized linear mixed model with a Poisson distribution and random intercepts were used to examine municipality-specific associations between short-term exposure to air pollutants and IVT-treated IS. We recorded 96,189 IS cases with a dominance of females (52.5%) and patients 65 years old and over (78.8%). 10,486 (10.9%) patients received IVT treatment. In this group there was lower share of women (51.3% vs. 52.7%, p < 0.001), fewer elderly individuals (76% vs. 79.1%, p < 0.001), and lower in-hospital mortality (13.6% vs. 15.5%, p < 0.001). The rate of IVT use increased significantly from 3.2% in 2011 to 18.3% in 2020 (Kendall’s τ = 0.956, p < 0.001). Exposure to benzo(a)pyrene was associated with the highest negative effects, causing 10.3% and 13.5% increase in risk of IVT-treated IS on LAG 0 and LAG 0–6 in the overall population, respectively. There was also an association between increased PM2.5 and IVT-treated incidence across all analyzed populations. Exposure to NO2 significantly increased the risk of IVT-treated IS only in females. Increases in SO2 and O3 levels did not influence IVT-treated incidence. There were no age or sex differences in the effects of air pollution exposure. Exposure to air pollution might serve as a trigger for IVT-treated IS, exerting a comparable effect across different sexes and age groups. The IVT-treated IS group was characterized by improved survival. Public health efforts should focus on reducing air pollution levels and ensuring rapid access to advanced IS treatment in high-risk, highly polluted areas. ClinicalTrials.gov (NCT05198492).