Teenage cannabis use is linked with a higher risk of developing psychiatric disorders in adolescence and young adulthood, according to a massive study co-authored by USC Price School Professor Rosalie Liccardo Pacula, who is also a senior scholar at the USC Schaeffer Institute.
- What they researched: Study authors examined a large cohort of 463,396 adolescents (ages 13 to 17) in a Northern Californian health system over ten years (2013-2023). The teenagers were universally screened for past-year cannabis use and followed through about age 26 to see if cannabis use was associated with new diagnoses of psychotic, bipolar, depressive, or anxiety disorders.
- What they found: Adolescents reporting past-year cannabis use had about double the risk of being diagnosed later with psychotic and bipolar disorders, even after controlling for other substance use and prior disruptive disorders, as well as increased risk for depressive and anxiety disorders.
- Why it matters: With cannabis becoming more legally available and socially accepted, there are growing concerns about its potential impact on adolescent mental health. While effects on adults may differ from those studied here, adolescent brains are still developing and hence are more vulnerable to negative outcomes. The findings of this large study highlight the importance of early prevention, clinician and parent education, and policies aimed at reducing youth cannabis exposure as legalization expands.
Read the study in JAMA Health Forum and NPR’s coverage of the study
