Bronchodilator Responsiveness and Airflow Limitation Are Associated With Deployment Length in Iraq and Afghanistan Veterans

OBJECTIVE: The aim of this study was to determine the relationship between deployment length and indices of airflow obstruction in Iraq and Afghanistan veterans with airborne hazards exposure. METHODS: One hundred twenty-four post-9/11 veterans completed pulmonary function testing and questionnaires. We examined the association of airflow limitation [forced expiratory volume in 1 second (FEV1)/forced vital capacity (FVC)] and bronchodilator responsiveness (ΔFEV1 and ΔFVC) with deployment length, adjusting for smoking. RESULTS: Longer deployment length was associated with lower FEV1/FVC [β = -0.19; 95% confidence interval (95% CI), -0.39 to 0.01], greater ΔFEV1 (β = 0.27; 95% CI, 0.09 to 0.45) and ΔFVC (β = 0.19; 95% CI, 0.05 to 0.33). In our model adjusted for smoking history, longer deployment length remained associated with greater ΔFEV1 and ΔFVC (P < 0.01), but not with FEV1/FVC (P = 0.059). CONCLUSION: In our sample of post-9/11 veterans, longer deployment lengths were associated with significant bronchodilator responsiveness and a trend toward airflow limitation independent of tobacco use.