Electronic cigarette (e-cigarette) use may be associated with an increased risk of chronic obstructive pulmonary disease (COPD), according to study results published in Journal of Public Health.
It is well established that tobacco smoking is the primary risk factor for COPD. However, there are little data examining the relationship between e-cigarette use and COPD. To address this gap, researchers used data from the 2018 Behavioral Risk Factor Surveillance Survey (BRFSS) to study the possible relationship between e-cigarette use and COPD. They collected data on COPD status, e-cigarette use, and combustible (ie, conventional) cigarette use. Variables such as past month leisure activity and demographics (age, sex, race, marital status, education level and BMI) were also included in the analysis.
Of the 177,209 individuals who participated in the survey, 7175 were current e-cigarette users, 26,260 were current combustible cigarette smokers, 3253 were dual users of e-cigarettes and combustible cigarettes, and 9569 individuals self-reported being diagnosed with COPD. Because of the known correlation between asthma and COPD, respondents with asthma were excluded.
Adjusting for covariates, a multivariable logistic regression model was run to assess the association between e-cigarette use and COPD. Compared with never e-cigarette users, the odds of having COPD was greater among daily e-cigarette users (odds ratio [OR], 1.53; 95% CI, 1.11-2.03), occasional users (OR, 1.43; 95% CI, 1.13-1.80), and former users (OR, 1.46; 95% CI, 1.28-1.67).
The relationship between e-cigarette users and COPD in current, former, and never combustible smokers was examined in a subgroup analysis. After controlling for covariates, a significant association was found between daily e-cigarette use and COPD in former combustible cigarette smokers (OR, 1.90; 95% CI, 1.25-2.88) and in never combustible cigarette smokers (OR, 3.17; 95% CI, 1.04-9.63) compared to former combustible smokers who were never e-cigarette users. However, no statistical association was found between e-cigarette use and COPD in current combustible smokers.
Researchers acknowledged limitations to this study. Firstly, data were self-reported which could have resulted in nonrandom misclassification as well as underreporting. Secondly, because the study was cross-sectional, results are not indicative of causal relationships. Thirdly, e-cigarette use was only quantified as daily, former, or never and did not reflect duration or degree of use. Also, the study did not include possible confounders including underlying risk factors. Lastly, although there was a relationship found between e-cigarette use and COPD, because the data were cross-sectional and observational, the study authors could not determine the direction of the association.
The study authors concluded that despite limitations, the findings provide a significant first step in studying the link between e-cigarette and COPD and suggests the need for further research.
Antwi G, Rhodes D. Association between E-cigarette use and chronic obstructive pulmonary disease in non-asthmatic adults in the USA. J Public Health (Oxf). doi:10.1093/pubmed/fdaa229