BACKGROUND AND AIMS

Cigarette smoking often results in nicotine dependence. With use of electronic cigarettes as an alternative source of nicotine, it is important to assess dependence associated with e-cigarette use. This study assesses dependence among current and former adult e-cigarette users on cigarettes and e-cigarettes, compared with dependence on cigarettes.

DESIGN

Cross-sectional data from the Population Assessment of Tobacco and Health (PATH) study from 2013-2016. Psychometrically assessed dependence was compared for cigarettes and e-cigarettes among current and former exclusive and dual users of the products and among e-cigarette users who had and had not recently stopped smoking. Setting A population-based representative sample of US adults. Participants Participants were 13 311 US adults (18+) in Waves 1-3 of PATH reporting current established smoking, current use of e-cigarettes, or stopping use of either product in the past year who were administered dependence assessments for cigarettes and/or e-cigarettes. Measurements A 16-item scale assessing tobacco dependence (on a 1-5 scale), previously validated for assessment and comparison of dependence on varied tobacco products, including cigarettes and e-cigarettes, with a variation assessing residual dependence among users who stopped in the past year. Findings Among current users, dependence on e-cigarettes was significantly lower than dependence on cigarettes, in within-subjects comparisons among dual users of both e-cigarettes and cigarettes (1.58 [SE = 0.05] vs. 2.76 [0.04]), P < 0.0001), and in separate groups of e-cigarette users and cigarette smokers (1.95 [0.05] vs. 2.52 [0.02], P < 0.0001), and among both daily and non-daily users of each product. Among former users, residual symptoms were significantly lower for e-cigarettes than cigarettes, both among former dual users (1.23 [0.07] vs. 1.41 [0.06], P < 0.001) and among users of one product (1.28 [0.03] vs. 1.53 [0.03], P < 0.0001). The highest level of e-cigarette dependence was among e-cigarette users who had stopped smoking (2.17 [0.08]). Conclusion Use of e-cigarettes appears to be consistently associated with lower nicotine dependence than cigarette smoking.