Abstract
RATIONALE: Post-traumatic stress disorder (PTSD) has been associated with asthma in cross-sectional studies. Whether PTSD leads to clinically significant bronchodilator response (BDR) or new-onset asthma is unknown. OBJECTIVES: We sought to determine the relationship between probable PTSD and both BDR and incident asthma in a high-risk cohort of World Trade Center workers in New York (NY). METHODS: This study was conducted on data from a high-risk cohort of 11,481 World Trade Center workers in New York, including 6,133 never smokers without a previous diagnosis of asthma. Of the 6,133 never smokers without asthma, 3,757 (61.3%) completed a follow-up visit several years later (mean = 4.95 yr, interquartile range = 3.74-5.90 yr). At the baseline visit, probable PTSD was defined as a score 44 points or greater in the PTSD Checklist questionnaire, and BDR was defined as both a change of 12% or greater and an increment of 200 ml or greater in FEV(1) after bronchodilator administration. Incident asthma was defined as a self-report of new physician-diagnosed asthma after the baseline visit. Multivariable logistic regression was used for the analysis of probable PTSD and baseline BDR or incident asthma. Measurements and Main and Results: At baseline, probable PTSD was associated with BDR among all participants (adjusted odds ratio = 1.43; 95% confidence interval = 1.19-1.72), with similar results among never smokers without asthma. Among 3,757 never smokers, probable PTSD at baseline was associated with incident asthma, even after adjustment for baseline BDR (odds ratio = 2.41; 95% confidence interval = 1.85-3.13). This association remained significant in a confirmatory analysis after excluding 195 subjects with baseline BDR. CONCLUSIONS: In a cohort of adult workers exposed to a severe traumatic event, probable PTSD is significantly associated with BDR at baseline and predicts incident asthma.