Original Investigation
November 2015

Progression to Traditional Cigarette Smoking After Electronic Cigarette Use Among US Adolescents and Young Adults

Author Affiliations
  • 1Division of General Internal Medicine, Department of Medicine, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania
  • 2Center for Research on Media, Technology, and Health, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania
  • 3Division of Adolescent Medicine, Department of Pediatrics, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania
  • 4Norris Cotton Cancer Center, Geisel School of Medicine, Dartmouth University, Hanover, New Hampshire
  • 5Dartmouth Institute for Health Policy and Clinical Practice, Geisel School of Medicine, Dartmouth University, Hanover, New Hampshire
  • 6Oregon Social Learning Center, College of Education, University of Oregon, Eugene
  • 7Center for Health Equity and Research Promotion, VA Pittsburgh Healthcare System, Pittsburgh, Pennsylvania
  • 8Department of Pediatrics, Geisel School of Medicine, Dartmouth University, Hanover, New Hampshire

Copyright 2015 American Medical Association. All Rights Reserved. Applicable FARS/DFARS Restrictions Apply to Government Use.

JAMA Pediatr. 2015;169(11):1018-1023. doi:10.1001/jamapediatrics.2015.1742

Importance  Electronic cigarettes (e-cigarettes) may help smokers reduce the use of traditional combustible cigarettes. However, adolescents and young adults who have never smoked traditional cigarettes are now using e-cigarettes, and these individuals may be at risk for subsequent progression to traditional cigarette smoking.

Objective  To determine whether baseline use of e-cigarettes among nonsmoking and nonsusceptible adolescents and young adults is associated with subsequent progression along an established trajectory to traditional cigarette smoking.

Design, Setting, and Participants  In this longitudinal cohort study, a national US sample of 694 participants aged 16 to 26 years who were never cigarette smokers and were attitudinally nonsusceptible to smoking cigarettes completed baseline surveys from October 1, 2012, to May 1, 2014, regarding smoking in 2012-2013. They were reassessed 1 year later. Analysis was conducted from July 1, 2014, to March 1, 2015. Multinomial logistic regression was used to assess the independent association between baseline e-cigarette use and cigarette smoking, controlling for sex, age, race/ethnicity, maternal educational level, sensation-seeking tendency, parental cigarette smoking, and cigarette smoking among friends. Sensitivity analyses were performed, with varying approaches to missing data and recanting.

Exposures  Use of e-cigarettes at baseline.

Main Outcomes and Measures  Progression to cigarette smoking, defined using 3 specific states along a trajectory: nonsusceptible nonsmokers, susceptible nonsmokers, and smokers. Individuals who could not rule out smoking in the future were defined as susceptible.

Results  Among the 694 respondents, 374 (53.9%) were female and 531 (76.5%) were non-Hispanic white. At baseline, 16 participants (2.3%) used e-cigarettes. Over the 1-year follow-up, 11 of 16 e-cigarette users and 128 of 678 of those who had not used e-cigarettes (18.9%) progressed toward cigarette smoking. In the primary fully adjusted models, baseline e-cigarette use was independently associated with progression to smoking (adjusted odds ratio [AOR], 8.3; 95% CI, 1.2-58.6) and to susceptibility among nonsmokers (AOR, 8.5; 95% CI, 1.3-57.2). Sensitivity analyses showed consistent results in the level of significance and slightly larger magnitude of AORs.

Conclusions and Relevance  In this national sample of US adolescents and young adults, use of e-cigarettes at baseline was associated with progression to traditional cigarette smoking. These findings support regulations to limit sales and decrease the appeal of e-cigarettes to adolescents and young adults.