Cannabis use disorder (CUD) — or problematic use — among adults increased after legalization of recreational marijuana use, according to a new study from Columbia University Mailman School of Public Health and New York University (NYU) School of Medicine. Among adults aged 26 or older, past-month use after legalization was 26 percent higher than in non-recreational states. Similarly, frequent use rose by 23 percent, and CUD increased by 37 percent in these legal states. The study is the first to look at the impact of recreational marijuana legalization on both use and cannabis use disorder across multiple age groups.
“Research has shown that cannabis use disorder can be associated with long-term adverse health, economic and social consequences,” said Dr. Silvia S. Martins, associate professor of epidemiology at Columbia University Mailman School of Public Health, and the study’s senior author. “Given our findings, legalization efforts should happen in tandem with funding for prevention and treatment. The general public should be informed about both benefits and potential harms of marijuana products to make informed decisions.”
The researchers analyzed data from the National Survey on Drug Use and Health with a sample of 505,796 respondents. They looked at data from CO, WA, AK, and OR from 2008-2016, the first four states to legalize marijuana for recreational use, and compared trends to states that had not legalized recreational use. They also examined marijuana use and frequent use in the past month, and CUD over the past year.
The researchers also reported: