Ontario students more likely to drive after consuming cannabis than alcohol

Poll of 1,161 Ontario students shows attitudes toward cannabis differ from alcohol, creating potentially risky and dangerous driving behaviour

Ontario students are more likely to get behind the wheel of a vehicle after smoking cannabis than drinking alcohol, a new study from researchers at the University of Ottawa's Faculty of Medicine has revealed.

The study, published in Preventive Medicine, found 10 percent of licensed Ontario high school students reported driving within an hour of cannabis use. Driving after drinking alcohol was much less prevalent, with 3.5 percent of students doing so.

The study, led by master's student Nathan Cantor, found that students who favour cannabis legislation and perceive cannabis to be less risky were more likely to report driving after cannabis use. The study found that graduated licencing programs tended to sway behaviours with students holding a G2 licence four times more likely to report driving after cannabis use compared to those with a G1 licence.

"This work reveals that Ontario adolescents perceive cannabis to be less risky than alcohol, and this perception affects other risky behaviours," says principal investigator Dr. Ian Colman, a Full Professor in the School of Epidemiology and Public Health. "The reason this is important is that it suggests that educating adolescents about the risks of cannabis use may be effective in reducing the dangerous practice of driving after cannabis use."

"We need to debunk the myth that cannabis use does not impair drivers," says Cantor, lead author of the study whose data originates from the period prior to the legalization of recreational cannabis in Canada.

"There's a good evidence base that shows acute cannabis consumption is associated with an increased risk of motor vehicle crash, especially for fatal collisions. This association is likely even greater in adolescents—this population has less driving experience, and proportionally represent a higher burden of motor vehicle crashes."

The study polled 1,161 students with valid driver's license about their driving behaviors, drug use, and attitudes regarding cannabis use as part of the 2017 Ontario Student Health and Drug Use Survey. The authors note the prevalence of cannabis-impaired driving should be continuously monitored moving forwards.