Adolescents’ Use of Nicotine-Free and Nicotine E-Cigarettes: A Longitudinal Study of Vaping Transitions and Vaper Characteristics

Abstract

Introduction Although adolescents’ nicotine addiction from e-cigarettes is a concern, few studies differentiate between vaping with and without nicotine. This study examines the prevalence of nicotine and nicotine-free vaping, maps transitions between vaping behaviours, and assesses differences in the personal characteristics of vapers in a sample of Norwegian adolescents. Methods Data came from a nationwide longitudinal study of adolescents (n=2,018) conducted in 2017 (T1), 2018 (T2) and 2019 (T3) (mean age: 14.2, 15.0 and 16.2). Using an online questionnaire, we measured vaping with and without nicotine, snus use, smoking, sensation-seeking, conduct problems and levels of depression. Results Past 12-month vaping prevalence was stable (12%, 13% and 15%). Among adolescents reporting vaping at T1, 69% had used e-cigarettes without nicotine, 17% with nicotine, and 15% were unsure of nicotine content. Individual vaping trajectories were unstable: of nicotine-free vapers, 54% became non-users, whilst 14% became nicotine vapers from T1-T2. From T2-T3, 50% became non-users, whilst 17% became nicotine vapers. Of nicotine vapers, 39% became non-users from T1-T2, whilst 46% became non-users from T2-T3. Compared to nicotine-free vapers, nicotine vapers had more conduct problems (mean=3.67 vs 2.17), had more symptoms of depression (mean=11.38 vs 6.95), and comprised more past-30-day snus users (33% vs 14%) and cigarette users (33% vs 9%). Conclusions Adolescent vapers most commonly used e-cigarettes without nicotine, few of these transitioned into nicotine vaping, and a majority became non-users. Nicotine vapers were more likely to use other tobacco products and have more conduct problems and symptoms of depression compared to nicotine-free vapers. Implications Reporting the prevalence of nicotine-free vaping is critical for assessing nicotine exposure and subsequent risks of nicotine addiction. This multi-cohort longitudinal study showed that use of nicotine-free e-cigarettes is common among young vapers in Norway. Adolescents’ vaping patterns – both with and without nicotine – are generally temporal and experimental. Despite the majority of nicotine vapers becoming non-users, they are characterised by having more conduct problems and poorer mental health, and they more often used other tobacco products.

Development of a nicotine aerosol self-administration model in rats and the effects of e-liquid flavors

“…In support of this hypothesis, a past study demonstrated that mice self-administered more green apple-flavored aerosol than unflavored aerosol (Cooper et al ., 2021). Consequently, the self-administration of the flavored vehicle in the present study may mimic human use of zero-nicotine flavored e-liquids, which is common among adolescents (Korfei, 2018; Tokle et al ., 2022). Because the present data from paired vs. unpaired vehicle groups are not sufficient to determine whether flavored aerosol maintained responding, additional research is warranted to examine if the raspberry flavored aerosol is reinforcing for rats by comparing self-administration of raspberry flavored vs. unflavored aerosol.…”

Single, Dual, and Triple Use of Cigarettes, e-Cigarettes, and Snus among Adolescents in the Nordic Countries

“…The users’ patterns varied somewhat between the countries, and especially, Iceland differed considerably from the other countries, with a very high proportion of single e-cigarette users. Earlier studies have shown connections between use of different tobacco, tobacco-like, and nicotine products among adolescents [ 12 , 23 , 32 , 33 ]. Even though the proportions of dual and triple users varied by country in our study, the results show that multiple substance use is common in all Nordic countries.…”

“…Secondly, we do not have data on whether e-cigarettes contained nicotine or not. There could be differences in the use of nicotine and non-nicotine e-liquids between the Nordic countries, as differences have been found between European countries [ 12 , 23 ]. Third, we had to use data for different years (2015 and 2019) to be able to compare all Nordic countries.…”

“…The majority of adolescents who report the use of e-cigarettes are also found to have experience with other tobacco products [ 1 , 7 , 12 , 15 , 23 ]. However, smoking cessation is only rarely mentioned among youth as a reason for using e-cigarettes, and flavors, curiosity, peer influence, and perceptions of e-cigarettes as “cool” and harmless have been reported as the top reasons for experimentation with them [ 15 , 24 , 25 , 26 ].…”

“…However, smoking cessation is only rarely mentioned among youth as a reason for using e-cigarettes, and flavors, curiosity, peer influence, and perceptions of e-cigarettes as “cool” and harmless have been reported as the top reasons for experimentation with them [ 15 , 24 , 25 , 26 ]. In addition, studies differentiating between using e-cigarettes with and without nicotine have shown that many adolescents report the use of nicotine-free e-cigarettes [ 12 , 23 ].…”