Researchers from the Universities of Pennsylvania and Southern California recently conducted a longitudinal study on adolescent nicotine and cannabis use. Teens who vape or smoke hookah are up to four times more likely to use cannabis later, the study found. Results were published in the journal, Pediatrics.
In fall of 2013, over 2,600 Los Angeles high school freshmen responded to pen-and-paper, online, and telephone surveys. The surveys asked students whether they used nicotine (except smokeless tobacco or cigars) or cannabis products, either within the last 30 days or ever. Two years later, in 2015, students responded to a follow-up survey that asked if they had ever smoked, vaped, or eaten cannabis products.
Students who vaped as freshmen were three times more likely to have used cannabis products by their junior year, results showed. Freshmen who used hookah were four times more likely to have used cannabis as juniors than freshmen who hadn’t.
Despite the decline in cigarette smoking among the youth, “we’ve seen an increase in use of these other tobacco products,” lead author Janet Audrain-McGovern told CNN. Audrain-McGovern also notes the “lessening of the restrictions of marijuana use” across the US as pertinent to their findings.
Researchers controlled for variables like depression and family history of tobacco and cannabis use in their study. The authors, instead, concentrated on sociopolitical and advertising efforts that impact adolescent decision-making. Audrain-McGovern, et al write the “youth are attracted by the novelty of e-cigarettes and a wide variety of flavors specifically designed to appeal to the youth market. If youth e-cigarette use follows the same pattern as cigarette smoking, widespread use could expose youth to social environments that encourage substance use, thereby accelerating youths’ transitions to the use of other substances with more adverse health effects.”
Eleven percent of high school students vape, according to the study, which is greater than the percentage of students who smoke combustible cigarettes. Dr. Ana Navas-Acien, professor of environmental health sciences at Columbia University, tells CNN, however, “that doesn’t mean necessarily that the association is causal. I think we need to be very careful with interpreting these relationships.”
“Our study revealed that e-cigarette use was associated with an increased risk of subsequent marijuana use among youth, with a stronger temporal association among younger adolescents,” the study reads. However, the authors also acknowledge that “future studies are needed to investigate the underlying mechanism of substance transition and evaluate long-term impacts of e-cigarette use.”