Bottom Line: Most 10th-graders who had ever used cannabis had used more than one type of the drug, including cannabis products that were combustible, edible or vaporized.
Why The Research Is Interesting: Cannabis use in adolescents is associated with increased risk for chronic use throughout adulthood, cannabis use disorder, impaired cognitive development and lower educational attainment. New cannabis products raise concerns about pediatric health amid the legalization of medical and recreational cannabis in some states and an increasing normalization of cannabis use in society.
Who and When: 3,177 10th-graders from 10 Los Angeles, California, area high schools surveyed from January to October 2015
What (Study Measures and Outcomes): Self-reported sex, race/ethnicity and socioeconomic status (exposures); self-report of ever use and past 30-day use of cannabis, as well as the frequency of use (number of days in past 30 days) of combustible, edible and vaporized cannabis (outcomes)
How (Study Design): This was a survey study.
Authors: Adam M. Leventhal, Ph.D., the Keck School of Medicine of University of Southern California, Los Angeles, and co-authors
Results: Of the 33.9 percent of 10th-graders (1,077 of 3,177) who reported ever using cannabis, combustible cannabis was the most popular followed by cannabis products that were edible or vaporized. Most 10th-graders who had ever used cannabis (665[61.7 percent]) used multiple products to administer the drug.
Study Limitations: Whether 10th-graders who used two or more different cannabis products initiated cannabis use with noncombustible products and later transitioned to combustible cannabis or vice versa was unclear; and the survey didn't differentiate cannabis products by potency, strain or types of cannabis formulation