Patterns of youth cigarette experimentation and onset of habitual smoking

Introduction Although research suggests that youth e-cigarette experimentation is associated with later combustible cigarette experimentation, it is unclear how this relates to habitual smoking. This study assesses how minors’ patterns of combustible cigarette and e-cigarette experimentation relate to habitual smoking at ages 18–21 years. Methods Between November 2016 and May 2017, a cross-sectional, online survey of current and retrospective cigarette use was fielded among individuals aged 18–21 years who had tried combustible cigarettes or e-cigarettes (n=1,424). Logistic regressions tested how experimentation patterns prior to age 18 years related to two indicators of current habitual smoking: daily smoking and current established smoking (past 30-day use among those who had smoked ≥100 cigarettes). Results Respondents who first tried combustible cigarettes or e-cigarettes as minors (n=1,096) were more likely to be current established users (64%) than those who first experimented at ages 18–21 years (41%). Experimentation patterns in individuals aged 17 years (n=328), trying only combustible cigarettes as a minor yielded a 175% increase in one's odds of being an established smoker (AOR=2.75, 95% CI=1.99, 3.79) and a 161% increase for daily smoking (AOR=2.61, 95% CI=1.75, 3.90). Trying combustibles and then e-cigarettes yielded sizable increases in both habitual smoking measures, whereas trying e-cigarettes before combustibles yielded smaller effects. Trying only e-cigarettes as a minor yielded a 78% decrease in both outcomes, relative to those who did not try either product as minors. Conclusions Minors who tried combustible cigarettes were more likely to be habitual smokers at ages 18–21 years than those who tried e-cigarettes alone.