In a new study just published in the American Journal of Psychiatry, researchers found that any use of marijuana was associated with increased risk of self-reported psychotic disorders. The study included data on over 75,000 subjects who participated in the National Epidemiologic Survey on Alcohol and Related Conditions (NESARC) from 2001-2002 or 2012-2013. In the analysis, the investigators used logistic regression to estimate prevalence of past-year self-reported psychotic disorders among users and non-users of marijuana. They found that compared to non-users, participants with any history of nonmedical marijuana use were 6.1 (2001-2002 survey) and 2.8 (2012-2013 survey) times more likely to experience a psychotic disorder. In further analyses of data from the 2012-2013 survey, frequent (>3x/week) or daily marijuana users were 4.1 and 3.7 times more likely to experience a psychotic disorder, respectively. This association was not present in the data from the 2001-2002 survey.
Drug Free America Foundation epidemiologist Dr. Sharif Mohr stated “The results of this study provide further confirmation of what we already know—use of high-potency marijuana products drastically increases risk of developing psychotic disorders and schizophrenia. The increasing normalization of marijuana use, coupled with the growing availability of high-potency marijuana products throughout the country, will likely result in a large increase in mental illness at the population level”
Source: Livne O, Shmulewitz D, Sarvet AL, Wall MM, Hasin DS. Association of Cannabis Use-Related Predictor Variables and Self-Reported Psychotic Disorders: U.S. Adults, 2001-2002 and 2012-2013. Am J Psychiatry. 2021