Declining Rates of Adolescent Marijuana Use Disorders During the Past Decade May Be Due to Declining Conduct Problems

The article by Grucza et al. in this issue of the Journal uses data from the National Survey on Drug Use and Health from 2002 to 2013 to examine trends of past-year adolescent marijuana use and DSM-IV marijuana use disorders in a large (N = 216,852), nationally representative sample of adolescents. The primary findings are that there has been a modest (9.8%) decrease during that period in past-year marijuana use in 12- to 17-year-olds and a more substantial (24%) decrease in past-year marijuana use disorders. Grucza et al. examined several potential protective or risk factors as possible explanations for these findings, specifically conduct problems, permissive parental attitudes toward substance use, parental monitoring, positive parental relationships, exposure to drug education, religious commitment, and number of activities outside school. What stood out was that a decrease in conduct problems accounted for the decrease in marijuana use disorders. In particular, in marijuana users without conduct problems, there was no decrease in the prevalence of marijuana use disorders; however, there was a decrease in the development of marijuana use disorders in those with conduct problems. Another finding of interest to clinicians is that overall rate of marijuana use disorders in 12- to 17-year-olds was quite high, with a past-year prevalence of 3.5%, which was higher than substance use disorders for all other illicit substances combined (1.8%) and only slightly lower than alcohol use disorders (4.9%).