Predictors of continued e-cigarette use included low-cost, desire to quit smoking cigarettes, and the ability to use e-cigarettes anywhere, a small longitudinal survey of middle and high school students found.
The most common reasons teens gave for initially trying e-cigarettes were curiosity, a cool factor and because of their friends. But six months later, none of those reasons were significant predictors of continued e-cigarette use, reported Krysten W. Bold, PhD, of Yale University, in New Haven, Conn., and colleagues, writing in Pediatrics.
Only 5.9% of students said they tried e-cigarettes in an effort to quit smoking, but smoking cessation was the only reason that was significantly associated with continued e-cigarette use in a multivariate analysis, albeit with wide confidence intervals (adjusted OR 14.54, 95% CI 1.80-117.80, P<0.05). Other demographic predictors of continued use were combustible cigarette use and younger age at e-cigarette initiation.
The authors also noted that after 6 months, 80% of teens who said they were using e-cigarettes to quit smoking were still smoking traditional cigarettes.
Harold J. Farber, MD, of Texas Children's Hospital in Houston, told MedPage Today via email that this study was impressive not for what was found, but for what was not found, especially in terms of predictors for continued use.
"Coolness, appeal, flavors, low cost, use by peers, etc. drives initiation, but nicotine dependence drives continued use," said Farber, who was not involved with the research. "These results highlight the great importance of prevention of initiation of e-cigarette use by youth."
Bold and colleagues also examined predictors of the frequency of e-cigarette use among teens. Not surprisingly, good flavors, hiding from adults and the ability to use anywhere were several reasons for trying e-cigarettes that predicted more frequent use, while curiosity was more likely to be associated with less frequent use. After 6 months, the biggest predictor of continued frequent use of e-cigarettes was low cost.
Regulatory strategies can be instrumental in preventing e-cigarette use in the first place, and Bold told MedPage Today separately that she hoped the results of their research might be able to inform such programs and policies.
"Many reasons youth cite for trying e-cigarettes speak more to programs at state and federal level," she said. "States differ in terms of types of programs implemented, but if there's a way to put restrictions on minor purchasing or increasing taxation, that could have a big impact."
Bold added that some states, such as Connecticut, are already restricting the use of e-cigarettes in non-smoking facilities.
Researchers examined 340 ever e-cigarette users in middle school and high school in two waves: Wave 1 in fall 2013 and wave 2 in spring 2014. This subsample was 47.4% girls and 86.2% white, with a mean age of 15.6 years. Covariates included age, sex, race and smoking of traditional cigarettes.
While two waves of this study have been completed, the third wave is ongoing -- with this same cohort of students, in an attempt to track their patterns of use over time.
"The best science is going to come from these longitudinal studies where we can follow people over long-term and see what the potential risks of e-cigarette use are," added Bold. "There's still a lot we don't know."