Flavored E-cigarette Use and Cigarette Smoking Reduction and Cessation-A Large National Study among Young Adult Smokers.

Background: E-cigarette use prevalence has increased drastically among young adult cigarette smokers in recent years.

Objectives: This study seeks to understand which e-cigarette flavors-sweet and fruity or tobacco and menthol/mint-are more likely to be associated with smoking reduction and cessation among young adults.

Methods: Longitudinal data (waves 1 and 2) of the Population Assessment of Tobacco and Health (PATH) Study from young adult (aged 18-34) cigarette smokers (n = 4,645) at wave 1 and current e-cigarette users (n = 844) at wave 2 were used. Univariate and multivariate regressions were conducted to examine the associations between past-year smoking reduction and cessation and current e-cigarette flavor use at wave 2.

Results: At wave 2, 25.9% of respondents either reduced or quit smoking, and 6.7%, 5.2%, and 6.3% of them reported currently using e-cigarettes with tobacco/menthol (TM) flavors, one non-tobacco/non-menthol (NTM) flavor, and multiple NTM flavors, respectively. E-cigarette users with one (AOR = 2.5, p < 0.001) and multiple NTM flavors (AOR = 3.0, p < 0.001) were more likely to have reduced or quit smoking over the past year compared to non-e-cigarette users. NTM flavor use was positively associated with e-cigarette use of a higher frequency and larger amount.

Conclusions: The positive association between past-year smoking reduction and cessation and current NTM flavored e-cigarette use may be explained by young adults' escalated e-cigarette use with NTM flavors. Public health professionals should prevent and reduce multiple tobacco use through enhanced education about the harm of vaping NTM flavors and by advising young adult smokers to quit tobacco altogether using evidence-based methods.