E-cigarettes, Cigarettes, and the Prevalence of Adolescent Tobacco Use

Introduction:
This text is a summary of a research study examining the relationship between e-cigarette use and tobacco use among adolescents. The study aims to determine whether e-cigarettes are a substitute for cigarettes or a gateway to tobacco use for non-smoking adolescents. The study uses data from the Southern California Children's Health Study (CHS) spanning over 20 years and five cohorts of adolescents.

Key Points:

* The study found that e-cigarette use among adolescents has increased rapidly in recent years, surpassing cigarette use for the first time in several national studies.
* The study compared the rate of total e-cigarette or cigarette use in 2014 to the rate of cigarette use in 2004 before e-cigarettes were available, and found that the rate of combined use in 2014 was similar to or greater than that for cigarette use alone 10 to 15 years ago.
* The study also found that the prevalence of ever cigarette use in 2014 was substantially higher than the adjusted prevalence of ever cigarette use in 2004, and slightly higher than the adjusted prevalence in 2001.
* The study examined the prevalence of cigarette and e-cigarette use by sex and ethnicity and found that the patterns of decline in smoking over time were similar for both male and female adolescents and for both non-Hispanic white adolescents and Hispanic adolescents.
* The study also found that the combined prevalence of e-cigarette or cigarette use (both current and ever) was greater in Hispanic whites than non-Hispanic whites in 11th grade, but the opposite was true in 12th grade.
* The study adjusted for the Cohort E distribution of race/ethnicity, sex, and parental education, indicating that differences across cohorts were unlikely to be influenced by changes in sociodemographic characteristics of the population over time.
* The study did not collect data on tobacco products other than cigarettes from earlier cohorts, and thus, the contribution of hookah, cigar/cigarillo, pipe, or smokeless tobacco use to the prevalence of all tobacco product use in earlier cohorts is not known.

Main Message:
The main message of this study is that e-cigarette use among adolescents is not merely substituting cigarettes but is instead recruiting a new group of users who would not likely have initiated combustible tobacco product use in the absence of e-cigarettes. This poses a potential threat to the public health of adolescent populations, and further research is needed to understand the role of e-cigarettes in nicotine addiction and whether e-cigarette users who have not used combustible cigarettes will progress to combustible cigarette users or dual users of both products.

Barrington-Trimis, Jessica L., Robert Urman, Adam M. Leventhal, W. James Gauderman, Tess Boley Cruz, Tamika D. Gilreath, Steve Howland, et al. “E-Cigarettes, Cigarettes, and the Prevalence of Adolescent Tobacco Use.” Pediatrics 138, no. 2 (August 1, 2016): e20153983. https://doi.org/10.1542/peds.2015-3983.