title: Acute exacerbation of idiopathic pulmonary fibrosis associated with air pollution exposure.
abstract: Acute exacerbations of idiopathic pulmonary fibrosis are associated with high mortality and are of unknown cause. The effect of air pollution on exacerbations of interstitial lung disease is unknown. This study aims to define the association of air pollution exposure with acute exacerbation of idiopathic pulmonary fibrosis. Patients with idiopathic pulmonary fibrosis and corresponding air pollution data were identified from a longitudinal cohort. Air pollution exposures were assigned to each patient for ozone, nitrogen dioxide, particulate matter, sulfur dioxide and carbon monoxide based on geo-coded residential addresses. Cox proportional hazards models were used to estimate the association of air pollution exposures and acute exacerbations. Acute exacerbation was significantly associated with antecedent 6-week increases in mean level, maximum level and number of exceedances above accepted standards of ozone (hazard ratio (HR) 1.57, 95% CI 1.09-2.24; HR 1.42, 95% CI 1.11-1.82; and HR 1.51, 95% CI 1.17-1.94, respectively) and nitrogen dioxide (HR 1.41, 95% CI 1.04-1.91; HR 1.27, 95% CI 1.01-1.59; and HR 1.20, 95% CI 1.10-1.31, respectively). Increased ozone and nitrogen dioxide exposure over the preceding 6 weeks was associated with an increased risk of acute exacerbation of idiopathic pulmonary fibrosis, suggesting that air pollution may contribute to the development of this clinically meaningful event.
authors.affiliation: University of California San Francisco, San Francisco, CA.
authors.forename: Kerri A
authors.initials: KA
authors.lastname: Johannson
authors.forename: Eric
authors.initials: E
authors.lastname: Vittinghoff
authors.forename: Kiyoung
authors.initials: K
authors.lastname: Lee
authors.forename: John R
authors.initials: JR
authors.lastname: Balmes
authors.forename: Wonjun
authors.initials: W
authors.lastname: Ji
authors.forename: Gilaad G
authors.initials: GG
authors.lastname: Kaplan
authors.forename: Dong Soon
authors.initials: DS
authors.lastname: Kim
authors.forename: Harold R
authors.initials: HR
authors.lastname: Collard
mesh_terms: D000368:Aged; D000393:Air Pollutants / Q000032:analysis*; D000397:Air Pollution / Q000032:analysis*; D002248:Carbon Monoxide / Q000032:analysis; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D054990:Idiopathic Pulmonary Fibrosis / Q000209:etiology*; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged; D009585:Nitrogen Dioxide / Q000032:analysis; D010126:Ozone; D052638:Particulate Matter / Q000009:adverse effects; D016016:Proportional Hazards Models; D056910:Republic of Korea; D012307:Risk Factors; D012907:Smoking; D013458:Sulfur Dioxide / Q000032:analysis; D016896:Treatment Outcome
chemical_list: D000393:Air Pollutants; D052638:Particulate Matter; D013458:Sulfur Dioxide; D010126:Ozone; D002248:Carbon Monoxide; D009585:Nitrogen Dioxide