The danger e-cigarettes pose to teenagers appears to be increasing the longer e-cigarettes go unregulated. A study in the January issue of Pediatrics found 29% of teenagers surveyed have tried e-cigarettes – with 62% of those reporting using them in the last month, and 44% of those using them three or more times in the last month. Researchers also found that 67% of respondents considered e-cigarettes to be “healthier” than regular cigarettes.

Lead author Thomas A. Wills, PhD, professor at the University of Hawaii Cancer Center in Manoa, pointed out that teenagers may not realize e-cigarettes contain nicotine, which is an addictive substance. “One Surgeon General’s report in fact documented that, in several aspects, nicotine is more addictive than heroin,” Wills said.

As e-cigarette use among the total population has doubled every year since 2009, teenagers have mirrored those trends. The National Youth Tobacco Survey reports e-cigarette ever-use among teenagers was up significantly from 4.7% in 2011 to 10.1% in 2012.

There are two possible hypotheses behind the appeal of e-cigarettes to teenagers, according to the study. In one model, e-cigarettes act as a less dangerous alternative to cigarettes and were preferred by teenagers with “conservative and health oriented values.” In another model, teenagers see e-cigarettes as similar to alcohol and marijuana: a way to “rebel against conventional values.”

However, the data was unable to confirm either explanation. Although both notions are plausible, there is little empirical evidence to support or reject either theory at this time, the authors wrote.

Researchers surveyed 1,941 students in three public and two private high schools in Oahu. The mean age of respondents was 14.6 (SD = 0.7), with a 47% to 53% male-to-female demographic breakdown. Parental consent and adolescent ascent were both required to participate in a 40-minute survey, and the response rate was 76%.

To determine the prevalence of e-cigarette use compared with cigarettes, alcohol, and marijuana, respondents were asked to determine frequency of use on a scale of 0-6 (0 being “Never” and 6 being “Daily”). E-cigarette ever-use (1-2 times or more) was nearly double that of actual cigarettes (15%) and marijuana (18%), though it ranked second behind alcohol (47%).

The study then examined psychosocial variables divided into categories thought to predict risk-seeking behavior: Social-cognitive risk factors, social-cognitive protective factors, and problem-behavior risk factors. When e-cigarette users were contrasted with users of both e-cigarettes and regular cigarettes, researchers reported dual users had a higher positive correlation (P>0.001) with social and behavioral risk factors.

Respondents who only used e-cigarettes did not score high on variables such as rebelliousness, sensation seeking, and peer smoker affiliations when compared with dual users, the authors wrote. But because they scored higher on these risk factors than their nonsmoking counterparts, the study determined e-cigarette users likely fall into an “intermediate risk group.”

But when the study crossed e-cigarette users who also frequently used cigarettes, alcohol, or marijuana, there was a correlation (P>0.001) with 14 out of 15 psychosocial variables. Statements such as “I like to break the rules,” “Smoking helps you feel more [self-confident]” and “Do any of your friends smoke cigarettes” exhibited the greatest correlation with e-cigarette users who frequently used other substances.

“Our findings suggest that e-cigarettes may be operating to recruit lower-risk adolescents to smoking,” said Wills. He also points out that both cigarette and e-cigarette use has increased among teenagers, which is difficult to reconcile with the contention that tobacco is being put out of business [by e-cigarettes], he said.

The most important limitation of the study may be its location. Hawaii has particularly aggressive advertising for e-cigarettes, and the authors pointed out that may lead to parents seeing e-cigarettes as a more desirable alternative and buying them for adolescents. Other limitations include lack of information about how long teenagers have been using e-cigarettes and that the survey only collected data in one sitting.

“It would be desirable to follow a group of adolescents … and obtain several assessments about e-cigarette use and cigarette use in order to determine how one type of use affects other types of use over time,” Wills said.