High School Students Using e-Cigarettes to Vape Cannabis

Liam Davenport

September 09, 2015

Almost a fifth of high school students who have tried e-cigarettes are using them to vaporize ("vape") cannabis, suggest findings of a study that reveal the extent to which e-cigarettes have taken root among adolescent students.

The study indicates that more than a quarter of high school students have ever used e-cigarettes and that almost one third have tried cannabis. Of those who have ever used e-cigarettes and cannabis, more than a quarter have used an e-cigarette to vaporize cannabis, whether as hash oil, delta-9-tetrahydrocannabinol (THC) wax, or dried leaves.

The researchers, who surveyed almost 4000 high school students in Connecticut, say: "The current study is the first to demonstrate that high school students are using e-cigarettes to vaporize cannabis."

The findings also indicate that male students and younger students were more likely to vaporize cannabis than other students and that rates were unaffected by socioeconomic status (SES).

"Factors such as the acceptability of cannabis use within a school (ie, 'cannabis culture') or the extent to which a school has explicit policies prohibiting e-cigarette use may play a more important role in encouraging or deterring vaporizing cannabis than students' SES," the researchers, with lead author Meghan E. Morean, PhD, Department of Psychology, Oberlin College, in Ohio, and the Department of Psychiatry, Yale University School of Medicine, New Haven, Connecticut, write.

Responding to the findings, leading experts argue that although the practice may offer some reductions in the harms associated with smoking cannabis, more research is required both into the impact of vaping cannabis via an e-cigarette and the increased use of e-cigarettes in general among adolescents.

The study was published online on September 7 in the journal Pediatrics.

Anonymous Survey

An anonymous survey on attitudes toward the use of e-cigarettes and other common substances of use or abuse, including marijuana, was completed by 3847 students (mean age, 16 years) attending five high schools in southeastern Connecticut.

The results indicated that overall, 27.9% of the participants had ever used e-cigarettes, that 29.2% had ever used cannabis, and that 5.4% had vaporized cannabis via an e-cigarette.

The proportion of individuals who had ever vaporized cannabis via e-cigarettes rose to 18.0% among ever–e-cigarette users, 18.4% of ever-cannabis users, and 26.5% of ever-users of both e- cigarettes and cannabis.

In terms of the types of cannabis being vaporized, hash oil was used via an e-cigarette by 15.4% of ever–e-cigarette users, 15.5% of ever-cannabis users, and 22.9% of ever-users of both e- cigarettes and cannabis. The equivalent figures for THC wax consumed via an e-cigarette were 10.0%, 10.2%, and 14.8%, respectively. The proportion of respondents using dried leaves via portable vaporizers was 19.6%, 23.1%, and 29.1%, respectively.

On further analysis using binary logistic regression, the likelihood of vaporizing cannabis with e-cigarettes was increased among male students, younger students (with age as a continuous variable), lifetime e-cigarette users, and lifetime cannabis users (odds ratio, 2.05, 0.64, 5.27, 40.89, respectively).

Relatively Novel Method

Dr Morean told Medscape Medical News that vaporizing cannabis is "a relatively novel way of consuming cannabis."

"Being able to vaporize cannabis has been around for some time, so that isn't in itself inherently novel, but just understanding the rates at which kids are using these products was not well established," she said.

She added: "Even with these results...we're testing the waters here. We don't know the extent to which that's representative of kids in other states, or even in other areas of Connecticut, but this was really a first step in trying to see how prevalent this is."

Dr Morean explained that although the prevalence of the use of e-cigarettes to consume cannabis is worrying, "we don't know the extent to which it's worrying."

"Our study doesn't speak to this, but there certainly is research out there that points to there [potentially being] negative effects on the adolescent brain, for example, of using cannabis and other substances, alcohol, and you pretty much name it," she continued.

"We're worried about it from that perspective, but I think one of the things that is most concerning about this particular method of using cannabis is that it's not very easily detectable."

Dr Morean pointed out that, when used in an e-cigarette, cannabis does not smell as strongly as when smoked conventionally, which makes it more easily concealable. Moreover, the cannabis substances used, such as hash oil, can be considerably stronger than the forms that are smoked conventionally.

She said: "We're concerned that it might be stronger than what kids might be smoking or that they are just not aware of the fact that it could be stronger, so you could inadvertently get a whole lot higher than you anticipated."

Reducing Harm to Lungs

Joseph J. Palamar, PhD, MPH, assistant professor in the section on tobacco, alcohol, and drug use in the Department of Population Health, New York University Langone Medical Center, New York City, commented that more research is needed both into the use of e-cigarettes to consume cannabis and into which cannabis users are vaping.

Speaking to Medscape Medical News, he said that in comparison with traditional joint smoking, there may be health benefits for marijuana users who vape marijuana, adding: "Vaping appears to be a good way of reducing potential harm to your lungs if you reject abstinence."

"Anyone who engages in any potentially risky or unhealthy behavior should use harm reduction," Dr Palamar continued. "This is why we wear seatbelts when we drive, helmets when we ride bikes, and condoms when we have sex."

"People who insist on smoking weed and do so by vaporizing are merely practicing harm reduction. We don't want teens smoking weed at all, but if they do, it's probably much safer if they vape."

Noting that the smell of cannabis is not as strong with e-cigarettes as when smoking it, Dr Palamar said that vaping may reduce the chances of a user being detected or arrested.

"Since arrest is one of the most serious consequences of marijuana use ― if not the most serious consequence ― then in this sense, vaping may also reduce harm associated with arrest," he said.

"Again, we shouldn't condone teens smoking marijuana via any method, even in states where recreational use is now legal, but if a teen insists of smoking it, it does appear to be a bit safer to vape rather than smoke using a more traditional method."

New Phenomena

Also approached for comment, Michael Weitzman, MD, professor, Departments of Pediatrics and Environmental Medicine, New York University School of Medicine, New York City, described the research as "extremely important," because it "draws attention to new phenomena that have profound public health implications."

Although the study did not offer anything new in terms of "anecdotes," inasmuch he is aware of "countless" young people who use marijuana with e-cigarettes, he continued: "You need anecdotes to change people's behavior, but you need hardcore data to develop rational, clinical, and public health policy, and this is the first study that I'm aware of with this combination."

Dr Weitzman pointed that little is known about the nonpsychoactive effects of marijuana and that multiple new forms of the drug are available. Moreover, there are "at least two and probably more" psychoactive components in marijuana, alongside numerous other constituents, which remain to be fully elucidated.

Using cannabis via e-cigarettes may reduce exposure to some constituents of marijuana, but "it also may lead to more potent or higher levels of the psychoactive components," Dr Weitzman told Medscape Medical News.

These components are associated with impairment of executive functioning and coordination and an increase in distractibility. In the adolescent brain, there are data to suggest that brain development is affected and that motivation may be reduced.

A further concern is the increasing use of e-cigarettes among adolescents. Dr Weitzman said that nicotine is the "most addictive drug" of which we are aware, adding: "Nicotine is more difficult, once you are addicted to it, to break the habit of than is cocaine or heroin."

"So if using e-cigarettes for marijuana use translates into increased use of e-cigarettes for nicotine, then you are exposing kids to a profoundly addictive chemical that, in itself, has many untoward biologic effects."

Citing a recent article in the New England Journal of Medicine, Dr Weitzman said that nicotine not only alters synaptic connections and the molecular function of the brain but also may be "the most potent gateway drug there is."

Consequently, "e-cigarettes may be a profound public health problem in terms of facilitating drug use, which has enormous implications," he concluded.

The research was supported by a grant from the National Institute of Drug Abuse (NIDA). Dr Morean and several coauthors were also partially supported by the National Institute on Alcohol Abuse and Alcoholism, the NIDA, and Clinical and Translational Science Award grants.

Pediatrics. Published online September 7, 2015. Abstract


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