Association between Air Pollutants and Initial Hospital Admission for Ischemic Stroke in Korea from 2002 to 2013

Abstract

Objectives: There is limited information regarding the association between air pollution exposure and stroke incidence. Therefore, this study aimed to assess the associations between short-term exposure to ambient air pollutants and initial hospital admission for ischemic stroke. Materials and Methods: From the Korea National Health Insurance Service–National Sample Cohort 2002–2013 database in South Korea, 55,852 first hospital admissions for ischemic stroke were identified. A generalized additive Poisson model was used to explore the association between air pollutants, including particulate matter, sulfur dioxide, nitrogen dioxide, and carbon monoxide and admissions for ischemic stroke. Results: All air pollutant models showed significant associations with ischemic stroke in the single lag model. In all air pollutant models excluding particulate matter 10 μm, a significant association was found between nitrogen dioxide exposure and initial admission for ischemic stroke after adjusting for other pollutants. An increment of 10 μg/m3 in nitrogen dioxide concentration at lag 0 and 14 days corresponded to a 0.259% (95% confidence interval, 0.231–0.287%) and 0.110% (95% confidence interval, 0.097–0.124) increase in initial admission for ischemic stroke, respectively. Conclusions: The exposure-response relationship between nitrogen dioxide and initial admissions for ischemic stroke was approximately linear, with a sharper response at higher concentrations. Short-term exposure to nitrogen dioxide was positively associated with initial hospital admission for ischemic stroke.