A Retrospective, Time-Stratified, Case-Crossover Study of the Effect of PM2.5 on Asthma Exacerbations in Wisconsin's Rural Counties

Abstract

Air pollution is a pervasive environmental health hazard with the potential to worsen respiratory health outcomes, including asthma exacerbations. The impact of PM on asthma exacerbations among 2.5 rural populations is not well understood. Our analysis used a retrospective, time-stratified, case-crossover study design to examine the relationship be tween PM and asthma exacerbations. We included asthma exacerbations 2.5 that occurred January 1, 2019–June 30, 2022, among residents of seven ru ral counties in Wisconsin with a PM air monitor. We also used PM data 2.5 2.5 collected by the Wisconsin Department of Natural Resources and weather data available from the National Oceanic and Atmospheric Administration (NOAA). Further, we used conditional logistic regression to assess the asso ciation between asthma exacerbations and lagged PM levels, adjusting for 2.5 maximum daily temperature. We found PM levels (µg/m3) 2 days prior to 2.5 exacerbation were significantly associated with asthma exacerbations (haz ard ratio 1.184; 95% confidence interval [1.051, 1.344]). Our study dem onstrated an increased hazard of asthma exacerbations with higher levels of PM in rural populations. These findings highlight the need for further 2.5 research and efforts to mitigate the effects of air pollution in rural areas.

Publication
Journal of Environmental Health