One of the excuses that e-cigarette advocates have used to dismiss the papers linking e-cigarette use with lung disease — that most e-cigarette users are current or former smokers — just got blown away with publication of a new study by Emine Bircan and colleagues of the association between e-cigarette use and lung disease in never-smokers.
In their paper “Electronic cigarette use and its association with asthma, chronic obstructive pulmonary disease (COPD) and asthma-COPD overlap syndrome among never cigarette smokers,” published in Tobacco Induced Disease, they estimated the odds of asthma and COPD in e-cigarette users in the Behavioral Risk Factor Surveillance System (BRFSS) from 2016 to 2018. Controlling for demographic factors using propensity score matching, they found that e-cigarette use was associated with increased odds of asthma by a factor of 1.26 (CI 1.25-1.27) and chronic obstructive pulmonary disease of 1.44 (1.42-1.46) and both of 2.27 (2.29-2.31).
Interestingly these risks are about the same that Dharma Bhatta and I estimated in our longitudinal study of the association between e-cigarette and lung disease, controlling for any current or former smoking of 1.29 (1.03-1.61). In that study we concluded that the effects of e-cigarette and cigarette use were independent; the similar results in the Bircan paper of nonsmokers only supports our earlier conclusions.
The new results are also consistent with the risks of e-cigarette use (controlling for smoking) in a recent meta-analysis of e-cig use and pulmonary disease that found studies of asthma yielded a pooled adjusted odds ratio of 1.39 (CI 1.28-1.51) for asthma and 1.49 (CI 1.36-1.65) for COPD.
I am still waiting for the e-cig enthusiasts to seriously engage the evidence of substantial pulmonary and cardiovascular risks of e-cig use.
Here is the abstract:
Introduction. Although smoking is a strong risk factor for lung diseases including asthma, COPD, and asthma-COPD overlap syndrome (ACOS), studies are needed to examine the association between e-cigarettes and asthma, COPD, and ACOS. This study evaluated the association between e-cigarette use and self-reported diagnosis of asthma, COPD, and ACOS using a large nationally representative sample of adults aged ≥18 years in the United States.
Methods. Cross-sectional data from the Behavioral Risk Factor Surveillance System (BRFSS) from 2016 to 2018 was used to examine self-reported information on current e-cigarette use, demographic variables, and asthma and COPD status among never cigarette smokers (n=8736). Asthma and COPD were measured by self-reported diagnosis, and respondents who reported having both diagnoses were then classified as having ACOS. Of the 46079 never cigarette smokers, 4368 non-e-cigarette smokers were 1:1 propensity score-matched to e-cigarette smokers on age, sex, race/ethnicity and education level. We used multinomial logistic regression to examine association between current e-cigarette use and self-report asthma, COPD, and ACOS while controlling for marital status and employment in addition to matching variables.
Results. Compared with never e-cigarette smokers, e-cigarette smokers had increased odds of self-reported ACOS (OR=2.27; 95% CI: 2.23–2.31), asthma (OR=1.26; 95% CI: 1.25–1.27) and COPD (OR=1.44; 95% CI: 1.42–1.46).
Conclusions. Data from this large nationally representative sample suggest that e-cigarette use is associated with increased odds of self-reported asthma, COPD, and ACOS among never combustible cigarette smokers. The odds of ACOS were twice as high among e-cigarette users compared with never smokers of conventional cigarettes. The findings from this study suggest the need to further investigate the long-term and short-term health effects of e-cigarette use, since the age of those at risk in our study was 18–24 years.
The full citation is: Bircan E, Bezirhan U, Porter A, Fagan P, Orloff MS. Electronic cigarette use and its association with asthma, chronic obstructive pulmonary disease (COPD) and asthma-COPD overlap syndrome among never cigarette smokers. Tob Induc Dis. 2021;19:23. Published 2021 Apr 7. doi:10.18332/tid/132833. It is available here.