Across nearly 22 million hospital visits in Arizona from 2016 to 2022, cannabis-related visits were consistently about seven times more likely to involve a psychotic disorder diagnosis than cannabis-unrelated visits.
Emergency clinicians, mental health researchers, and policymakers interested in cannabis-psychosis links at the population level.
~7x more likely to involve psychosis
What the researchers found
Cannabis-related hospital visits were approximately 7 times as likely to involve a psychotic disorder diagnosis as cannabis-unrelated visits, an association that remained stable from 2016 to 2022. The link was stronger for visits by females and adolescents.
Why it matters
As cannabis use and cannabis-related hospitalizations continue to rise, understanding the relationship between cannabis-related visits and psychotic disorders helps shape hospital screening and treatment coordination. The stability of this association across multiple years suggests it is not a temporary artifact of legalization changes.
The numbers in context
Cannabis-related visits increased 4.1% per year on average. Cannabis-related visits were ~7 times as likely to involve psychosis as cannabis-unrelated visits. Alcohol-related visits were ~3 times as likely. Alcohol-psychotic disorder associations decreased over time while cannabis-psychotic disorder associations stayed stable.
How the study worked
Researchers analyzed 21,934,060 emergency department and inpatient hospital visits in Arizona from 2016 to 2022 using ICD-10-CM codes. Poisson regression tested time trends in cannabis-psychotic disorder associations, with stratification by sex, age, and visit type.
What this study cannot tell us
Hospital visit data cannot establish causation. ICD-10-CM coding may misclassify some visits. People with psychotic disorders may be more likely to use cannabis (reverse causation). The study cannot account for THC potency or mode of consumption.
How to read the evidence
Large administrative dataset spanning 7 years with nearly 22 million visits and robust statistical methods, though limited by the inherent constraints of hospital coding data.
When this study was published
2025 publication analyzing 2016-2022 data
The bigger picture
This study adds to a growing body of evidence linking cannabis use with psychosis at the population level. The finding that adolescents and females showed stronger associations may inform targeted screening protocols in emergency departments.
Questions still open
- Why are cannabis-psychotic disorder associations stronger for females and adolescents? Are higher-potency products contributing to these patterns? Would coordinated care pathways reduce repeat cannabis-psychotic disorder visits?
Common questions
Did cannabis legalization in Arizona change the cannabis-psychosis link?
How did cannabis compare to alcohol for psychosis-related visits?
Read the original research
Associations between cannabis-related hospital visits and psychotic disorder-related hospital visits in Arizona from 2016 to 2022.
Drug and alcohol dependence, 273, 112717
Citation
Colby, Alana M; Barashy, Sivan; Miller, Matt L; Hummel, Haley M; Mun, Chung Jung; Meier, Madeline H. (2025). Associations between cannabis-related hospital visits and psychotic disorder-related hospital visits in Arizona from 2016 to 2022.. Drug and alcohol dependence, 273, 112717. https://doi.org/10.1016/j.drugalcdep.2025.112717
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