Short-term ambient air pollution risk for ischemic stroke hospitalization and related economic burden: A multi-city time-series study in southwest China

Short-term exposure to air pollution is associated with hospitalization for ischemic stroke (IS); however, evidence of the impact of the exposure on IS in highly polluted developing regions is limited. This study aimed to assess the relationships between air pollutants and IS hospitalization, as well as economic burden attributable to the hospitalization in Sichuan, China. Records from 160,555 IS hospitalizations were collected from medical institutions in nine cities in Sichuan from 2017 to 2019, along with simultaneous meteorological and air pollution data. Generalized additive model (GAM) was used to analyze the relationship between air pollutants and IS hospitalizations. The economic burden due to air pollutants exposure were further assessed using a cost-of-illness (COI) method. All p values were corrected for multiple comparisons. The single pollutant model showed that the effects of each interquartile range (IQR) increase in PM2.5, PM10, O3, and CO, on IS hospitalization peaked on lag 07, with relative risk values of 1.057(95% CI: 1.030–1.085), 1.060(95% CI:1.032–1.090), 1.110(95% CI:1.043–1.181), and 1.096 (95% CI:1.060–1.132), respectively. Stratified analysis shows that older people are more susceptible to the impact of air pollutants, and compared to the warm season, IS hospitalization in the cold season is more susceptible to exposure to O3 and CO. It has been determined that during the study period, the number of IS hospitalizations attributable to PM2.5 pollution was 5,157 and to PM10 pollution was 3,650, with an economic cost of CNY 67, 966, 100 and 48, 107, 900, respectively. In this study, we found that short-term exposure to PM2.5, PM10, O3, and CO can lead to increased hospitalizations for stroke and a quantifiably greater economic burden.