RT Journal Article
SR Electronic
T1 Nitrogen Dioxide Increases the Risk of Mortality in Idiopathic Pulmonary Fibrosis
JF European Respiratory Journal
JO Eur Respir J
FD European Respiratory Society
SP 2001877
DO 10.1183/13993003.01877-2020
A1 Hee-young Yoon
A1 Sun-Young Kim
A1 Ok-Jin Kim
A1 Jin Woo Song
YR 2020
UL http://erj.ersjournals.com/content/early/2020/11/05/13993003.01877-2020.abstract
AB Ambient air pollution is associated with prognosis of idiopathic pulmonary fibrosis (IPF) patients. We aimed to identify the impacts of individual exposure to particulate matter with aerodynamic diameter ≤10 μm (PM10) and nitrogen dioxide (NO2) on IPF patients' mortality.Total 1114 patients (mean age, 65.7 years; male, 80.5%) diagnosed with IPF between 1995 and 2016 were included in this study. Individual-level long-term concentrations of PM10 and NO2 at residential addresses of patients were estimated using a national-scale exposure prediction model. The effect of PM10 and NO2 on mortality was estimated using a Cox proportional hazards model adjusted for individual- and area-level covariates.The median follow-up period was 3.8 years, and 69.5% of all the patients died or underwent lung transplantation. When adjusted for individual- and area-level covariates, a 10-ppb increase in NO2 concentration was associated with a 17% increase in mortality (hazard ratio [HR], 1.172 [95% CI: 1.030–1.344, p=0.016]). When IPF patients were stratified by age (≥65 years versus <65 years) or by sex, NO2 was a significant prognostic factor for mortality in the elderly (HR, 1.331 [95% CI: 1.010–1.598, p=0.010]). When stratified by age and sex jointly, NO2 showed the stronger association with mortality in elderly male (HR, 1.305 [95% CI: 1.072–1.598, p=0.008]) than in other groups. PM10 was not associated with IPF mortality in all patients and in subgroups stratified by age or sex.Our findings suggest that increased exposure to NO2 can increase risk of mortality in patients with IPF, specifically in elderly men.FootnotesThis manuscript has recently been accepted for publication in the European Respiratory Journal. It is published here in its accepted form prior to copyediting and typesetting by our production team. After these production processes are complete and the authors have approved the resulting proofs, the article will move to the latest issue of the ERJ online. Please open or download the PDF to view this article.Conflict of interest: Dr. Yoon has nothing to disclose.Conflict of interest: Dr. Kim has nothing to disclose.Conflict of interest: Dr. Kim has nothing to disclose.Conflict of interest: Dr. Song has nothing to disclose.