ArticleThe International journal on drug policy2022
Impact of cannabis legalization on healthcare utilization for psychosis and schizophrenia in Colorado.
Article in The International journal on drug policy, 2022. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 11 papers, 1 of them a synthesis that pooled it.
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Who cites it
11 citing papers in PubMed, 1 synthesis or guideline pooled it, 32 citations in OpenAlex.
- A systematic review and meta-analysis of the prevalence of alcohol and other drug use and problematic use among people accessing mental health treatment in Australia.The Australian and New Zealand journal of psychiatry · 2025Pooled it
- Evidence-based atlas of risk and protective factors for psychotic disorders: an umbrella review to inform personalized prognosis and prevention.World psychiatry : official journal of the World Psychiatric Association (WPA) · 2026Article
- Hallucinogen-Psychosis Associations Are Confounded by Baseline Psychiatric History.The Journal of clinical psychiatry · 2026Article
- Falling Through the Cracks: Perspectives From Local Leaders on Substance Use and Psychosis Treatment for Youth.Journal of dual diagnosis · 2025Article
- Medical Cannabis Dispensary Availability Improved Self-Reported Mental Health among Older Adults in New York.Economics letters · 2025Article
- Measuring the Impact of Medical Cannabis Law Adoption on Employer-Sponsored Health Insurance Costs: A Difference-in-Difference Analysis, 2003-2022.Applied health economics and health policy · 2025Article
- The Impact of Adult Cannabis Use Legalization in California: A Qualitative Review of Subject Matter Expert Opinions on Proposition 64.Cannabis (Albuquerque, N.M.) · 2025Article
- Exploring the impact of drug decriminalization and legalization policies on mental health outcomes: A scoping review.PLOS mental health · 2025Article
- The association between physical availability of cannabis retail outlets and frequent cannabis use and related health harms: a systematic review.Lancet regional health. Americas · 2024Review
- Association between non-medical cannabis legalization and emergency department visits for cannabis-induced psychosis.Molecular psychiatry · 2023Article
- Cannabis Use Disorder Among People With and Without HIV.Journal of addiction medicineArticle
Corrections and comments
PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.
Authors and funding
6 authors at 4 institutions in 1 country.
Funding
Abstract
backgroundEmergency department (ED) visits involving psychosis and schizophrenia have increased at a rate exceeding population growth in the United States over the past decade. Research shows a strong dose-response relationship between chronic use of high-potency cannabis and odds of developing symptoms of psychosis. The aim of this study was to evaluate the impact of cannabis legalization on psychosis and schizophrenia-related ED visits in Colorado.
methodsUsing administrative data from Colorado Hospital Association (CHA) on county-level quarterly ED visits between January 1, 2013, and December 31, 2018, we applied a difference-in-difference analysis to examine how new exposure to recreational cannabis dispensaries after 2014 differentially influenced the rate of ED visits for psychosis and schizophrenia, comparing counties with no prior medical cannabis dispensary exposure to counties with low or high medical dispensary exposure.
resultsAs recreational dispensaries per 10,000 residents increased, there was no significant association with the rate of schizophrenia ED visits per capita (incidence rate ratio or IRR: 0.95, 95% CI [0.69, 1.30]) while the rate of psychosis visits increased 24% (IRR: 1.24, 95% CI [1.02, 1.49]). Counties with no previous medical dispensaries experienced larger increases in schizophrenia ED visits than counties already exposed to a low level of medical dispensaries, but this effect was not significant. Counties with low baseline medical exposure had lower increases in rates of psychosis visits than counties with high baseline medical exposure (IRR 0.83, 95% CI [0.69, 0.99]).
conclusionsThere was a positive association between the number of cannabis dispensaries and rates of psychosis ED visits across all counties in Colorado. Although it is unclear whether it is access to products, or the types of products that may be driving this association, our findings suggest there is a potential impact on the mental health of the local population that is observed after cannabis legalization.
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Registered trials
Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.