Geographical variation in hospitalization for psychosis associated with cannabis use and cannabis legalization in the United States
Lauren V. Moran, E. Tsang, D. Öngür, John Hsu, May Y. Choi
Psychiatry Research 2022 DOI: 10.1016/j.psychres.2022.114387 (opens in new tab)
Study at a glance
AI-extracted from the abstract| Characteristics | Observational study Peer reviewed |
|---|---|
| Population | Adults in the United States hospitalized in 2017, drawn from the National Inpatient Sample |
| Topics | Cannabis |
| Key findings | The Pacific census division, where most states had legalized recreational cannabis, had significantly higher adjusted odds of hospital discharge for cannabis-associated psychosis than other divisions (adjusted odds ratio 1.55; 95% confidence interval 1.25–1.93), and a cannabis legality score correlated with the proportion of such discharges (r=0.67). The authors conclude that areas with more liberal cannabis legalization laws had a higher proportion of these hospitalizations. |
Abstract
The 2017 National Inpatient Sample database was utilized to investigate the association between cannabis legalization in the United States and hospitalizations for psychosis associated with cannabis use. We compared the odds of hospital discharges for psychosis associated with cannabis use in adults between the Pacific census division (where most states legalized recreational cannabis use) and other divisions using multivariable logistic regression, adjusting for confounders. We calculated a score for each census division representing cannabis legality as the population-weighted sum of state scores: 1=illegal or cannabidiol/low potency cannabis; 2= medical marijuana; and 3=recreational and medical marijuana legalized. Pearson’s correlation coefficients (r) quantified the relationship between scores and the proportion of hospitalizations with psychosis associated with cannabis. In 2017, there were an estimated 129,070 hospital discharges for psychosis associated with cannabis use. The Pacific census division had significantly higher odds of discharges than other divisions (adjusted odds ratio 1.55; 95% confidence interval 1.25 – 1.93). There was a significant correlation between the cannabis legality score and proportion of hospital discharges for psychosis associated with cannabis use (r=0.67, p<0.05). In conclusion, we observed a higher proportion of hospital discharges for psychosis associated with cannabis use in areas with more liberal cannabis legalization laws.
Comparable studies
Other observational and cohort studies on cannabis, most cited first.
| Study | Year | Design | Participants |
|---|---|---|---|
| High-potency cannabis and the risk of psychosis People with first episode of psychosis and healthy controls from the local population | 2009 | Case-control study | n = 454 |
| Ayahuasca-Assisted Therapy for Addiction: Results from a Preliminary Observational Study in Canada Rural aboriginal population | 2013 | Observational study | |
| Impaired cognitive performance in drug free users of recreational ecstasy (MDMA) Otherwise healthy young people | 2000 | Observational | |
| Continued cannabis use and risk of incidence and persistence of psychotic symptoms: 10 year follow-up cohort study Individuals from the general population in Germany aged 14-24 at baseline | 2011 | Observational cohort | n = 1,923 |
| Cannabis-induced psychosis and subsequent schizophrenia-spectrum disorders: follow-up study of 535 incident cases Patients treated for cannabis-induced psychotic symptoms in Denmark between 1994 and... | 2005 | Observational cohort | n = 535 |
Citations in the library
Cited by 5
- Cannabis use and psychosis among patients hospitalized in psychiatric wards in Lebanon: a retrospective chart review Middle East Current Psychiatry November 13, 2023
- Emergency department use by individuals with and without psychosis after state-level cannabis legalization and commercialization Nature Mental Health June 19, 2026
- [Impact of the legalization of recreational cannabis on the risk of psychosis: A systematic review of the literature]. L'Encephale September 1, 2024
- Cannabis use among patients presenting to the emergency department for psychosis: Associations with restraint use, medication administration, psychiatric hospitalization, and repeat visits. Psychiatry Research March 17, 2023
- State Cannabis Legalization and Psychosis-Related Health Care Utilization JAMA Network Open January 25, 2023
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