Legalized Cannabis and Schizophrenia Risk For Kids
Understanding the Link Between Cannabis Use and Schizophrenia in Young Adults
Topline
New research from Ontario, Canada, reveals a sharp rise in schizophrenia cases linked to cannabis use disorder (CUD) following cannabis legalization. The study underscores concerns about increased cannabis potency and widespread use among young adults.
Study Details
A recent study published in JAMA Network Open examined the correlation between cannabis use disorder and schizophrenia diagnoses in Ontario over 16 years, spanning before and after cannabis legalization. Researchers analyzed medical records of over 13.5 million residents, investigating how cannabis policy changes influenced schizophrenia cases.
Methodology
The study segmented data into three policy periods: before legalization (2006–2015), after medical cannabis legalization (2015–2018), and after recreational cannabis legalization (2018–2022). Researchers tracked emergency department visits and hospital admissions related to cannabis use disorder and schizophrenia.
Key Findings
During the study period, 118,650 individuals (0.9%) required emergency or hospital care for cannabis use disorder.
10,583 (9%) of those with cannabis use disorder developed schizophrenia, compared to 80,523 (0.6%) of those without it.
Following full legalization, hospital visits for cannabis use disorder surged by 270%, from 1.3 per 1,000 individuals pre-legalization to 4.6 per 1,000 post-legalization.
The proportion of new schizophrenia cases linked to cannabis use disorder increased from 3.7% before legalization to 10.3% afterward, with young men (ages 19–24) being most affected.
Implications for Practice
For Patients: Young adults using high-potency cannabis should be aware of the potential mental health risks, including early-onset schizophrenia.
For Healthcare Providers: Physicians should screen for cannabis use disorder in at-risk populations and provide early interventions to mitigate long-term psychiatric consequences.
For Policymakers: The study highlights the need for regulatory oversight on cannabis potency and public education campaigns on mental health risks.