An additional 1.1 million adult illicit cannabis users and an additional 500,000 adults with a DSM-IV cannabis disorder may be attributable to medical marijuana law passage according to new research funded by the National Institute on Drug Abuse (NIDA) and the National Institute on Alcohol Abuse & Alcoholism (NIAAA), both part of the National Institutes of Health.
Comparing overall trends in states with medical marijuana laws to states without these laws, the authors examined data from three NIAAA-supported surveys conducted in 1991-1992, 2001-2002, and 2012-2013. In addition, the definition of cannabis use disorder was based upon the DSM-IV definition of cannabis abuse or dependence in the past 12 months. However, investigators also note there could be other contributing factors.
These findings underscore the importance of examining how more permissive state marijuana laws can increase the risk of cannabis-related health consequences. An accompanying commentary on the article by NIDA scientists highlights the potential negative effects of cannabis on mental health.