Changes in Incident Schizophrenia Diagnoses Associated With Cannabis Use Disorder After Cannabis Legalization
Daniel T. Myran, Michael Pugliese, Lyndsay D. Harrison, Marco Solmi, Kelly K. Anderson, Jess G. Fiedorowicz, Yaron Finkelstein, Doug Manuel, M. Taljaard, Colleen Webber, Peter Tanuseputro
JAMA Network Open February 1, 2025 DOI: 10.1001/jamanetworkopen.2024.57868 (opens in new tab)
Study at a glance
AI-extracted from the abstract| Characteristics | Population-based cohort study Peer reviewed |
|---|---|
| Sample size | 13,588,681 |
| Population | Canadian population (13,588,681 individuals) |
| Topics | Cannabis |
| Key findings | The population-attributable fraction of cannabis use disorder associated with schizophrenia increased significantly from 3.7% in the prelegalization period to 10.3% in the postlegalization period. The authors suggest this association is an important consideration for cannabis legalization policy. |
Abstract
Key Points Question Were the liberalization of medical cannabis and the legalization of nonmedical cannabis in Canada associated with changes in the population-attributable fraction of cannabis use disorders associated with schizophrenia? Findings In this population-based cohort study comprising 13 588 681 individuals, the population-attributable fraction of cannabis use disorder associated with schizophrenia increased significantly from 3.7% in the prelegalization period to 10.3% during the postlegalization period. Meaning These findings suggest that the association between cannabis use disorders and schizophrenia is an important consideration for the legalization of cannabis.