@article {472991,
	title = {Pneumothorax Risk Factors in Smokers with and without Chronic Obstructive Pulmonary Disease},
	journal = {Annals ATSAnnals ATS},
	volume = {11},
	year = {2014},
	month = {Oct 08},
	pages = {1387-1394},
	publisher = {American Thoracic Society - AJRCCM},
	abstract = {Rationale: The demographic, physiologic, and computed tomography (CT) features associated with pneumothorax in smokers with and without chronic obstructive pulmonary disease (COPD) are not clearly defined. Objectives: We evaluated the hypothesis that pneumothorax in smokers is associated with male gender, tall and thin stature, airflow obstruction, and increased total and sub-pleural emphysema. Methods: The study included smokers with and without COPD from the COPDGene study, with quantitative chest CT analysis. Pleural-based emphysema was assessed using local histogram measures of emphysema. Pneumothorax history was defined by subject self-report. Measurements and Main Results: Pneumothorax was reported in 286 (3.2\%) of 9,062 participants. In all participants, risk of prior pneumothorax was significantly higher in men (OR 1.55, 95\% CI 1.08 - 2.22) and non-Hispanic whites (OR 1.90, 95\% CI 1.34 - 2.69). Risk of prior pneumothorax was associated with increased percent CT emphysema in all participants and participants with COPD (OR 1.04 for each 1\% increase in emphysema, 95\% CI 1.03 - 1.06). Increased pleural-based emphysema was independently associated with risk of past pneumothorax in all participants (OR 1.05 for each 1\% increase, 95\% CI 1.01 - 1.10). In smokers with normal spirometry, risk of past pneumothorax was associated with non-Hispanic white race and lifetime smoking intensity (OR 1.20 for every 10 pack-years, 95\% CI 1.09 - 1.33). Conclusions: Among smokers, pneumothorax is associated with male gender, non-Hispanic white race, and increased percentage of total and sub-pleural CT emphysema. Pneumothorax was not independently associated with height or lung function, even in participants with COPD. ClinicalTrials.gov Identifier: NCT00608764.},
	author = {Hobbs, Brian D and Foreman, Marilyn G and Bowler, Russell and Jacobson, Francine and Make, Barry J and Castaldi, Peter J and San Jose Est{\'e}par, Ra{\'u}l and Silverman, Edwin K and Hersh, Craig P}
}