Two small but significant new studies are answering very big questions regarding e-cigarette use in teens and young adults. As suspected, the popular tobacco alternatives are a gateway to smoking. And they might also be tempting teens with a sneaky way to smoke pot, too.
The tobacco and teens study, published Tuesday in JAMA Pediatrics, was conducted by a “crackerjack” team of smoking researchers at the University of Pittsburgh School of Medicine and Dartmouth University, according to Fred Hutch smoking cessation expert Dr. Jonathan Bricker.
“They’ve been studying the influences on youth smoking for several decades,” he said. “There’s been a lot of debate about whether e-cigarettes are a gateway to smoking cigarettes. This study says, ‘Yes, it is a gateway to smoking cigarettes’ and that makes it significant.”
In the first national, longitudinal study to examine the e-cig gateway issue, researchers from the two institutions followed 694 U.S. teens and young adults aged 16 to 26 for a full year.
To be included, participants had to be “never smokers” as well as “non-susceptible to smoking” (NSNS), determined by asking if 1) they would try a cigarette offered by a friend and 2) they were likely to smoke a cigarette in the next year. Those who answered “definitely no” to both were considered NSNS; everyone else was defined as a “susceptible nonsmoker” (SNS).
At the start of the study, 16 of the 694 participants were e-cig smokers. After a year, six of the e-cig users had started smoking cigarettes and five more had become “susceptible nonsmokers,” i.e. they no longer felt certain they would not take up smoking in the next year. By comparison, just 128 of the 678 nonsmokers (and nonvapers) either started smoking cigarettes or indicated they might start.
Statistically, that means only 19 percent of nonsmokers turned to tobacco or thought they might while 38 percent of e-cig users actually became smokers and a whopping total of 69 percent of e-cig users progressed toward tobacco use.
“The most striking finding of the study was that initial e-cigarette users were very likely to progress to regular smoking, even though initially they did not intend on smoking regular cigarettes,” said lead author Dr. Brian Primack of the University of Pittsburgh School of Medicine.
His findings, he said, indicate e-cigs users are “about eight times as likely to progress” to smoking as non e-cig users.
“So many of the initial e-cigarette users progressed -- and so few of the non-e-cigarette users progressed -- that we can be confident that this is a real effect,” he said.
This is particularly worrisome because the rate of e-cig use in teens is skyrocketing. Recent data published by the Centers for Disease Control and Prevention and the U.S. Food and Drug Administration’s Center for Tobacco Products indicate e-cigarette use among middle and high school students has tripled in just one year.
Bricker noted that despite the small number of participants, the new study packed a statistical punch.
“That’s a powerful effect with a well-designed study,” he said. “And when you get that, you take it seriously.”
He also emphasized that this particular study was not about whether e-cigarettes are safer or whether they help adults stop smoking, but rather whether they lead teens and young adults to escalate from e-cigarettes to more dangerous cigarette use.
And the answer is a resounding yes.
“It’s not a commentary on e-cigarettes being a dangerous substance,” he said. “It’s a commentary on how they might normalize the behavior of smoking: the inhaling; the exhaling; the holding of the device for smoking. What it might be doing is basically habituating the body to nicotine in a small dose and then you need more to get a more powerful hit.”
The second study, published in the journal Pediatrics, focused on teens’ use of electronic cigarettes to smoke pot.
Researchers from Yale University and Oberlin College in Ohio surveyed 3,847 Connecticut high school students from five schools, asking about e-cig tobacco use, cannabis use and what devices they used for smoking one or the other.
The results, the first to show that teens are using e-cigs to vaporize pot, found that the practice was “common,” at least with regard to students who used e-cigs (18 percent), students who’d tried any form of cannabis (18.4 percent) and students who had experimented with both e-cigs and cannabis (26.5 percent).
Only 5.5 percent of the nearly 3,850 students surveyed said they used e-cigs to get high – mostly by loading the devices with hash oil, THC-infused wax or dried cannabis leaves—but the practice still raised concerns with researchers.
For one thing, smoking pot with a battery-powered e-cig device doesn’t give off the “pungent and characteristic odor of smoked cannabis,” making it tough for parents or police to track the behavior (and much easier for teens to surreptitiously smoke pot during class, at home or just walking around their neighborhood).
For another, THC concentrations are higher with vaporized hash oil and waxes, exceeding that of dried cannabis anywhere from 4 to 30 times.
“A recent study indicated that adults who vaporized hash oil experienced increased subjective tolerance and evidence of dependence relative to smoking combustible cannabis,” they wrote in their conclusion. “This increased risk likely is linked to the increased potency of hash oil and THC-infused waxes compared to combustible cannabis.”
Future research, they said, is needed to determine if e-cigarette use may serve as a gateway to cannabis use.
As for the proven e-cig gateway to tobacco, Fred Hutch’s Bricker said the University of Pittsburgh School of Medicine/Dartmouth study may prompt important policy changes.
“This is the kind of data that could make the FDA take e-cigarettes very seriously,” he said. “Right now, they’re taking in all the science and trying to decide how to regulate e-cigarettes. This is a result that says now the FDA really needs to start regulating sales to minors, marketing to minors and the flavoring of e-cigarettes that appeal to minors.”
Bricker said for him, the two studies are a “clear implication that you have to control access of e-cigarettes to young people.”
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Solid tumors, such as those of the lungs, are the focus of Solid Tumor Translational Research, a network comprised of Fred Hutchinson Cancer Research Center, UW Medicine and Seattle Cancer Care Alliance. STTR is bridging laboratory sciences and patient care to provide the most precise treatment options for patients with solid tumor cancers.
Diane Mapes is a staff writer at Fred Hutchinson Cancer Research Center. She has written extensively about health issues for NBC News, TODAY, CNN, MSN, Seattle Magazine and other publications. A breast cancer survivor, she also writes the breast cancer blog doublewhammied.com. Reach her at firstname.lastname@example.org.