Emergence of electronic cigarette use in US adolescents and the link to traditional cigarette use

Background Electronic cigarettes (e-cigarettes) are increasingly used by US adolescents and may be a gateway to traditional cigarette use. We examine rates of both products by age and examine differences in age-varying rates by sex and race/ethnicity. Methods Data are from the 2014 National Youth Tobacco Survey, a national sample of US middle and high school students (n = 22.007); students ages 11–19 were included. Past 30-day e-cigarette and traditional cigarette use were examined as a function of age; sex and race/ethnicity were included as moderators. The age-varying association between e-cigarette and traditional cigarette use was also examined. Results Rates of e-cigarette use increase faster than traditional cigarette use from ages 13–16. Compared to females, males had higher rates of e-cigarette use from ages 14–17.5 and traditional cigarette use from ages 15–18. Between ages 12–14, more Hispanic adolescents used e-cigarettes compared to White or Black adolescents; after age 14 Hispanics and Whites reported similar rates, peaking at twice the rate for Blacks. Hispanic adolescents report greater traditional cigarette use versus Whites between ages 12–13, but lower rates between ages 15–18. E-cigarette use was strongly associated with traditional cigarette use, particularly during early adolescence [OR > 40 before age 12]. Conclusions Young Hispanic adolescents are at elevated risk for use of e-cigarettes and traditional cigarettes during early adolescence. During early adolescence, youth using e-cigarettes are more likely to smoke traditional cigarettes compared to youth not using e-cigarettes. The study of age-varying effects holds promise for advancing understanding of disparities in health risk behaviors.