Scimex: In a study appearing in the November 8 issue of JAMA, Adam
M. Leventhal, Ph.D., of the University of Southern California Keck
School of Medicine, Los Angeles, and colleagues examined associations of
e-cigarette vaping with subsequent smoking frequency and heavy smoking
among adolescents. E-cigarette vaping is reported by 37 percent of U.S. 10th-grade
adolescents and is associated with subsequent initiation of combustible
cigarette smoking. Whether individuals who vape and transition to
combustible cigarettes are experimenting or progress to more frequent
and heavy smoking is unknown. In addition, because some adolescents use
e-cigarettes as a smoking cessation aid, adolescent smokers who vape
could be more likely to reduce their smoking levels over time.
This study consisted of an analysis of data from surveys administered
to 10th grade students in ten public high schools in Los Angeles County
during the fall (baseline for this report) and spring (6-month
follow-up) of 2014-2015. Surveys included e-cigarette and combustible
cigarette use questions from prior research, which were used to
determine baseline vaping and baseline and follow-up past 30-day smoking
frequency and heaviness.
Students with complete vaping and smoking data at baseline and
follow-up constituted the analytic sample (n = 3,084; 54 percent girls;
baseline average age, 15.5 years). The prevalence rates of past 30-day
vaping and smoking were low overall. Smoking frequency at follow-up was
proportionately greater with successively higher levels of baseline
vaping. Similar trends were found for smoking heaviness.
Adjusting for baseline smoking, each increment higher on the 4-level
baseline vaping frequency continuum was associated with proportionally
higher odds of smoking at a greater level of frequency and heaviness by
follow-up. The positive association between baseline vaping and
follow-up smoking frequency was stronger among baseline nonsmokers than
baseline infrequent and frequent smokers; similar trends were found for
smoking heaviness.
“The role of nicotine and generalizability of these results to other
locations and ages, longer follow-up periods, and non-self-report
assessments are unknown and merit further inquiry. The transition from
vaping to smoking may warrant particular attention in tobacco control
policy,” the authors write.