Middle and high school students in Canada who tried an e-cigarette are twice as likely to be susceptible to smoking cigarettes, which researchers call concerning.
In a study published in the journal Preventive Medicine, public health investigators analyzed data from the most recent Canadian Student Tobacco, Alcohol and Drugs Survey of students in grades seven to 12.
About 10 per cent of the sample of more than 25,000 students said they'd ever tried an e-cigarette.
These children and adolescents were more than twice as likely to report being susceptible to smoking cigarettes, after controlling for other potential factors such as living in areas of Canada with higher smoking rates, behavioural issues and feelings of social connectedness to parents and teachers."Intentions are a strong predictor of eventual tobacco use," study author Bruce Baskerville, a senior scientist at the University of Waterloo's Propel Centre for Population Health Impact, said Monday.
"What we're seeing in our sample is that there were a considerable number of kids who were intending on trying cigarettes. That's concerning to us because we've made great headway over the last decade in reducing the amount of tobacco use, particularly amongst young people, and we see the potential of e-cigarettes now as being a possible threat to that success."
The researchers defined susceptibility to smoking as a lack of a firm decision not to smoke in the future, based on answers to questions such as: "Do you think in the future you might try smoking cigarettes?"
'We think e-cigarette use may be facilitating the use of tobacco as the e-cigarette use they're mimicking the smoking behaviour and they're producing similar feelings.'- Bruce Baskerville
Of the 25,637 never-smoking students surveyed, 32 per cent or 8,423 were considered susceptible to smoking, the study's authors said.
About two per cent of students said they'd used e-cigarettes in the past 30 days.
While Health Canada had indicated since 2009 that e-cigarettes are regulated and need market authorization, which hasn't been approved, research from the Waterloo team testing e-cigarette products from a random sample of stores found half do contain nicotine.
The concern, Baskerville said, is that young people trying e-cigarettes are likely using products with nicotine and as a consequence, becoming addicted to it. Cigarettes are a very efficient delivery mechanism for nicotine.
"We think e-cigarette use may be facilitating the use of tobacco as the e-cigarette use they're mimicking the smoking behaviour and they're producing similar feelings," he said.
Baskerville pointed to several potential legislative ideas stemming from the findings, including:
The study was based on survey findings at one point in time and simply shows an association between e-cigarette use as a stepping stone to smoke cigarettes.
It isn't possible to test for a cause-and-effect relationship from such observational research. Longitudinal research in the U.S. that followed people from high school into adulthood supports the association.
Elizabeth Saewyc is a professor of nursing at the University of British Columbia who focuses on adolescent health. She was not involved in the vaping findings, which she said were based on a rigorous, national survey on substance use that offers important evidence in line with studies done in other countries.
If most e-cigarettes in Canada include nicotine then it is likely that young people who vape will end up addicted to nicotine, Saewyc said. Early use of nicotine can lead to regular, heavy use of nicotine products like cigarettes.For parents, it's important to have conversations about tobacco and vaping early and often to explain the risks of nicotine in e-cigarettes.
"It's important to make sure you explain the risks of nicotine in e-cigarettes, because if young people don't know whether the e-juice they're getting has nicotine in it, they may become dependent on nicotine without meaning to, and kicking that addiction can be really tough," Saewyc suggested, adding it also helps if parents set good examples.
Providing accurate, up-to-date information about the health risks of both cigarette use and e-cigarette use is important, said Saewyc, co-investigator of the Canadian team of the Health Behaviour of School-Age Children survey sponsored by the World Health Organization.
Saewyc also called on governments to enforce the existing rules around e-cigarette products with nicotine, including restricting access by minors, and for Canadians to keep enforcing social norms against smoking, second-hand smoke and maybe vaping.
Baskerville hopes to conduct a national study tracking young people as they mature to provide more conclusive evidence on the long-term effects of e-cigarette use, to make interprovincial comparisons to contribute to policy decisions.