Problematic Use

Marijuana use among adolescents and adults increased after legalization of recreational marijuana and that maybe problematic, according to a new study from New York University’s Grossman School of Medicine and Columbia University’s Mailman School of Public Health.

Published online November 13 in JAMA Psychiatry, the study claims to be the first to look at the impact of recreational marijuana legalization on both use and cannabis use disorder (commonly referred to as problematic marijuana use) across multiple age groups. Presently, 11 states and Washington, D.C. have legalized marijuana for recreational use while 33 states and D.C. have legalized marijuana for medical use.

After examining usage following the enactment of marijuana legalization in 2012 to 2015, the researchers found that problematic use among adolescents aged 12 to 17 was 25% higher (a small increase from 2.18 to 2.72%) compared to states without legal recreational use. There was no change in the prevalence of past-month or frequent use among teens.

Among adults aged 26 or older, past-month marijuana use after legalization was 26% higher than in non-recreational states. Past-month frequent use rose by 23%, and past-year problematic use increased by 37%.

Among young adults aged 18 to 25, there was no difference found in past-month, frequent or problematic marijuana use.

“There are, indeed, important social benefits that legalizing marijuana can provide, particularly around issues of equity in criminal justice,” said Magdalena Cerda, DrPH, associate professor and director of the Center for Opioid Epidemiology and Policy in the Department of Population Health at NYU Langone Health, and the study’s lead author. “Our findings suggest that as more states move toward legalizing marijuana for recreational use, we also need to think about investing in substance use prevention and treatment to prevent unintended harms — particularly among adolescents.”

Cerda and colleagues analyzed data from the National Survey on Drug Use and Health (NSDUH) with a sample of 505,796 respondents. The investigators specifically looked at data from Colorado, Washington, Alaska and Oregon from 2008-2016, the first four states to legalize marijuana for recreational use. They compared trends in these four states to trends in states that had not legalized recreational marijuana use. The team examined marijuana use and frequent use (more than 20 days) in the past month, and cannabis use disorder over the past year.

“Cannabis use disorder in adolescence is associated with long-term adverse health, economic and social consequences,” said Silvia S. Martins, MD, PhD, associate professor of Epidemiology at Columbia University Mailman School of Public Health, and the study’s senior author. “The general public should be informed about both benefits and potential harms of marijuana products to make informed decisions,” Martins added.

Topics Cannabis