Background Electronic cigarette (e-cigarette) use in the USA is increasing. As such, it is critical to understand who uses e-cigarettes, how e-cigarettes are used and what types of products are prevalent. This study assesses patterns of current e-cigarette use among daily and non-daily adult users in the 2013–2014 Population Assessment of Tobacco and Health (PATH) Study. Methods We examined the proportion of current adult e-cigarette users (n=3642) reporting infrequent use (use on ‘some days’ and use on 0–2 of the past 30 days), moderate use (use on ‘some days’ and use on >2 of the past 30 days) and daily use. We examined demographic characteristics, use of other tobacco products and e-cigarette product characteristics overall and by use category. Adjusted prevalence ratios (aPRs) were calculated using Poisson regression to assess correlates of daily e-cigarette use. Results Among the 5.5% of adult current e-cigarette users in the PATH Study, 42.2% reported infrequent use, 36.5% reported moderate use and 21.3% reported daily use. Cigarette smokers who quit in the past year were more likely to report daily e-cigarette use, compared with current smokers (aPR=3.21, 95% CI=2.75 to 3.76). Those who reported using rechargeable or refillable devices were more likely to report daily use compared with those who did not use these devices (aPR=1.95, 95% CI=1.44 to 2.65 and aPR=2.10, 95% CI=1.75 to 2.52, respectively). Conclusions The majority of e-cigarette users in this study reported less than daily use. Compared with non-daily use, daily use was associated with being a former smoker; however, cross-sectional data limits our ability to establish the temporality or directionality of such associations.

Introduction: Use of electronic nicotine delivery systems (ENDS), including electronic cigarettes (e-cigarettes), is increasing. One concern is the appeal of these products to youth and young adults and their potential to influence perceptions and use of conventional cigarettes. Methods: Using data from the 2012–2013 National Adult Tobacco Survey, characteristics of adults aged 18–29 who had never established cigarette smoking behavior were examined by ever use of e-cigarettes, demographics, and ever use of other tobacco products (smokeless tobacco, cigars, hookah, and cigarettes). Multivariate logistic regression was employed to examine the relationship between e-cigarette use and openness to cigarette smoking among young adults, defined as the lack of a firm intention not to smoke soon or in the next year. Results: Among young adults who had never established cigarette smoking behavior (unweighted n = 4,310), 7.9% reported having ever tried e-cigarettes—14.6% of whom reported current use of the product. Ever e-cigarette use was associated with being open to cigarette smoking (adjusted odds ratio = 2.4; 95% confidence interval = 1.7, 3.3), as was being male, aged 18–24, less educated, and having ever used hookah or experimented with conventional cigarettes. Conclusions: Ever use of e-cigarettes, as well as other tobacco products, was associated with being open to cigarette smoking. This study does not allow us to assess the directionality of this association, so future longitudinal research is needed to illuminate tobacco use behaviors over time, as well as provide additional insight on the relationship between ENDS use and conventional cigarette use among young adult populations.

Introduction This study assessed patterns of e-cigarette and cigarette use from Wave 1 to Wave 2 among adult e-cigarette users at Wave 1 of the Population Assessment of Tobacco and Health (PATH) Study. Methods We examined changes in e-cigarette use frequency at Wave 2 among adult e-cigarette users at Wave 1 (unweighted n=2835). Adjusted prevalence ratios (aPR) were calculated using a predicted marginal probability approach to assess correlates of e-cigarette discontinuance and smoking abstinence at Wave 2. Results Half (48.8%) of adult e-cigarette users at Wave 1 discontinued their use of e-cigarettes at Wave 2. Among dual users of e-cigarettes and cigarettes at Wave 1, 44.3% maintained dual use, 43.5% discontinued e-cigarette use and maintained cigarette smoking and 12.1% discontinued cigarette use at Wave 2, either by abstaining from cigarette smoking only (5.1%) or discontinuing both products (7.0%). Among dual users at Wave 1, daily e-cigarette users were more likely than non-daily users to report smoking abstinence at Wave 2 (aPR=1.40, 95% CI 1.02 to 1.91). Using a customisable device (rather than a non-customisable one) was not significantly related to smoking abstinence at Wave 2 (aPR=1.14, 95% CI 0.81 to 1.60). Conclusions This study suggests that e-cigarette use patterns are highly variable over a 1-year period. This analysis provides the first nationally representative estimates of transitions among US adult e-cigarette users. Future research, including additional waves of the PATH Study, can provide further insight into long-term patterns of e-cigarette use critical to understanding the net population health impact of e-cigarettes in USA.

In 2013–2014, nearly 28% of adults in the United States (U.S.) were current tobacco users with cigarettes the most common product used and with nearly 40% of tobacco users using two or more tobacco products. We describe overall change in prevalence of tobacco product use and within-person transitions in tobacco product use in the U.S. between 2013–2014 and 2014–2015 for young adults (18–24 years) and older adults (25+ years). Data from Wave 1 (W1, 2013–2014) and Wave 2 (W2, 2014–2015) of the Population Assessment of Tobacco and Health (PATH) Study were analyzed (N = 34,235). Tobacco product types were categorized into: (1) combustible (cigarettes, cigars, pipe tobacco, hookah), (2) noncombustible (smokeless tobacco, snus pouches, dissolvable tobacco), and (3) electronic nicotine delivery systems (ENDS). Transitions for individual combustible-product types, and for single- and multiple-product use, were also considered. Overall prevalence of current tobacco use decreased from 27.6% to 26.3%. Among W1 non-tobacco users, 88.7% of young adults and 95.8% of older adults were non-tobacco users at W2. Among W1 tobacco users, 71.7% of young adults transitioned, with 20.7% discontinuing use completely, and 45.9% of older adults transitioned, with 12.5% discontinuing use completely. Continuing with/transitioning toward combustible product(s), particularly cigarettes, was more common than continuing with/transitioning toward ENDS. Tobacco use behaviors were less stable among young adults than older adults, likely reflecting greater product experimentation among young adults. Relative stability of cigarette use compared to other tobacco products (except older adult noncombustible use) demonstrates high abuse liability for cigarettes.

More than half of adult tobacco users in the United States (U.S.) transitioned in tobacco product use between 2013–2014 and 2014–2015. We examine how characteristics of adult tobacco users in the U.S. relate to transitions in tobacco product use. Population Assessment of Tobacco and Health (PATH) Study data were analyzed from 12,862 adult current tobacco users who participated in Wave 1 (W1, 2013–2014) and Wave 2 (W2, 2014–2015). Three types of transitions were examined—(1) adding tobacco product(s); (2) switching to non-cigarette tobacco product(s); and (3) discontinuing all tobacco use—among those currently using: (1) any tobacco product; (2) cigarettes only (i.e., exclusive cigarette); and (3) cigarettes plus another tobacco product(s) (i.e., poly-cigarette). Multinomial logistic regression analyses determined relative risk of type of transition versus no transition as a function of demographic and tobacco use characteristics. Transitions in tobacco product use among adult tobacco users were common overall, but varied among different demographic groups, including by age, sex, sexual orientation, race/ethnicity, educational attainment, and poverty level. Further, cigarette smokers with higher dependence scores were more likely to add product(s) and less likely to discontinue tobacco use compared to those with low dependence scores. That high nicotine dependence is a barrier to discontinuing tobacco use adds evidence to support policy to lower nicotine content of cigarettes and to evaluate new products for their potential to reduce cigarette use.