Association Between E-Cigarette Use and Chronic Obstructive Pulmonary Disease by Smoking Status: Behavioral Risk Factor Surveillance System 2016 and 2017

Introduction: The association between e-cigarette use and chronic bronchitis, emphysema, and chronic obstructive pulmonary disease has not been studied thoroughly, particularly in populations defined by concomitant combustible smoking status. Methods: Using pooled 2016 and 2017 data from the Behavioral Risk Factor Surveillance System, investigators studied 705,159 participants with complete self-reported information on e-cigarette use, combustible cigarette use, key covariates, and chronic bronchitis, emphysema, or chronic obstructive pulmonary disease. Current e-cigarette use was the main exposure, with current use further classified as daily or occasional use. The main outcome was defined as reported ever having a diagnosis of chronic bronchitis, emphysema, or chronic obstructive pulmonary disease. For all the analyses, multivariable adjusted logistic regression was used, with the study population stratified by combustible cigarette use status (never, former, or current). All the analyses were conducted in 2019. Results: Of 705,159 participants, 25,175 (3.6%) were current e-cigarette users, 64,792 (9.2%) current combustible cigarette smokers, 207,905 (29.5%) former combustible cigarette smokers, 432,462 (61.3%) never combustible cigarette smokers, and 14,036 (2.0%) dual users of e-cigarettes and combustible cigarettes. A total of 53,702 (7.6%) participants self-reported chronic bronchitis, emphysema, or chronic obstructive pulmonary disease. Among never combustible cigarette smokers, current e-cigarette use was associated with 75% higher odds of chronic bronchitis, emphysema, or chronic obstructive pulmonary disease compared with never e-cigarette users (OR=1.75, 95% CI=1.25, 2.45), with daily users of e-cigarettes having the highest odds (OR=2.64, 95% CI=1.43, 4.89). Similar associations between e-cigarette use and chronic bronchitis, emphysema, or chronic obstructive pulmonary disease were noted among both former and current combustible cigarette smokers. Conclusions: The results suggest possible e-cigarette-related pulmonary toxicity across all the categories of combustible cigarette smoking status, including those who had never smoked combustible cigarettes. (C) 2019 American Journal of Preventive Medicine. Published by Elsevier Inc. All rights reserved.