Respiratory symptoms after coalmine fire and pandemic: a longitudinal analysis of the Hazelwood Health Study adult cohort

Abstract

AbstractBackgroundExtreme but discrete fine particle <2.5µm (PM2.5) exposure is associated with higher prevalence of respiratory symptoms. It is unknown whether these effects abate, persist, or worsen over time, nor whether COVID-19 exacerbates PM2.5effects.MethodsWe analysed longitudinal survey data from a cohort residing near a 2014 coalmine fire in regional Australia. A 2016/2017 survey includedn=4,056 participants, of whomn=612 were followed-up in 2022. Items include questions about 7 respiratory symptoms, history of COVID-19, and time-location diaries that were combined with geospatial models of fire-related PM2.5. Associations were examined using logistic and mixed-effects logistic regressions.ResultsPM2.5exposure predicted higher prevalence of chronic cough and current wheeze 2-3 years post-fire. At the 2022 follow-up, PM2.5exposure was associated with worsening prevalence of chronic cough and possibly current wheeze. While were no detectable interaction effects between PM2.5and COVID-19, participants with a history of COVID-19 exhibited more significant associations between PM2.5exposure and respiratory symptoms.DiscussionShort-term but extreme PM2.5may increase the long-term prevalence of chronic cough, while COVID-19 may exacerbate the effect on other respiratory symptoms.