Vaping characteristics and expectancies are associated with smoking cessation propensity among dual users of combustible and electronic cigarettes

Abstract

Background and aims: Most e-cigarette users who also smoke combustible cigarettes (dual users) begin vaping to quit smoking, yet only a subset succeeds. We hypothesized that reinforcing characteristics of e-cigarettes (vaping reinforcement) would positively predict smoking cessation propensity (SCP) among dual users.

Design: Secondary analysis of cross-sectional baseline data from dual users in an ongoing smoking cessation trial. Exploratory and confirmatory factor analysis (EFA and CFA) created latent variables for vaping reinforcement and SCP. A structural equation modeling (SEM) approach was used to test the hypothesis.

Setting: United States.

Participants: A national sample of dual users of combustible and electronic cigarettes who smoke and vape at least once per week (n = 2896) were enrolled (63% male; mean age = 29.9 years) into a randomized controlled trial in which they would receive either smoking cessation materials or no smoking cessation materials.

Measurements: Vaping reinforcement was indexed by vaping frequency (days/week vaping, times/day vaping, puffs/e-cigarette use), e-cigarette characteristics [numbers of modifications and tobacco or non-tobacco flavors, nicotine content (mg) and positive e-cigarette expectancies]. SCP was measured by items of confidence, commitment to being smoke-free, cessation motivation (contemplation ladder), change in cigarettes per day since beginning e-cigarette use and negative smoking expectancies.

Findings: Four factors emerged from the EFA: vaping propensity (vaping frequency, positive expectancies), vaping enthusiasm (e-cigarette modifications, using non-tobacco flavors, puffs per use), nicotine/tobacco flavor (nicotine strength, tobacco flavors) and SCP (negative expectancies about smoking, motivation to quit smoking, reduction in smoking). A CFA upheld the exploratory factor structure [root mean square error of approximation (RMSEA) = 0.046, CFI = 0.91]. An SEM with the three vaping latent variables directly predicting SCP had good model fit (RMSEA = 0.030, CFI = 0.97) with a positive relationship of vaping propensity (0.509, P < 0.001), and small negative relationships of vaping enthusiasm (-0.158, P = 0.014) and nicotine/tobacco flavor (-0.230, P < 0.001).

Conclusions: Among e-cigarette users who also smoke combustible cigarettes, frequent vaping combined with positive e-cigarette expectancies appears to predict greater smoking cessation propensity. However, vaping enthusiasm (measured by e-cigarette modifications, using non-tobacco flavors and puffs per use), higher nicotine content and use of tobacco flavored solution may reduce cessation propensity.

Keywords: Dual-use; e-cigarettes; latent variable; smoking; smoking cessation; structural equation modeling.