States with More Liberal Cannabis Laws Had More Psychosis Hospitalizations

In 2017, the U.S. Pacific census division (where most states legalized recreational cannabis) had 55% higher odds of psychosis-related hospitalizations associated with cannabis use.

Moran, Lauren V et al.·Psychiatry research·2022·Moderate EvidenceCross-Sectional
RTHC-04079Cross SectionalModerate Evidence2022RETHINKTHC RESEARCH DATABASErethinkthc.com/research

Quick Facts

Study Type
Cross-Sectional
Evidence
Moderate Evidence
Sample
Not reported

What This Study Found

There were an estimated 129,070 hospital discharges for psychosis associated with cannabis in 2017. The Pacific division had 55% higher odds of such discharges (aOR=1.55, 95% CI 1.25-1.93). A cannabis legality score correlated significantly with the proportion of psychosis-cannabis hospitalizations (r=0.67, P<0.05).

Key Numbers

129,070 psychosis-cannabis hospital discharges; Pacific division aOR 1.55; legality-psychosis correlation r=0.67 (P<0.05)

How They Did This

Analysis of the 2017 National Inpatient Sample database using multivariable logistic regression comparing psychosis-cannabis hospitalizations across U.S. census divisions. Cannabis legality scores were population-weighted sums of state-level legal status.

Why This Research Matters

This national-level data provides evidence that more liberal cannabis legalization is associated with more psychosis-related hospitalizations, a finding with direct policy implications.

The Bigger Picture

As more states legalize cannabis, monitoring psychiatric hospitalizations related to cannabis use becomes increasingly important. This geographic variation suggests legalization may have measurable public health impacts on psychosis.

What This Study Doesn't Tell Us

Cross-sectional data from one year. Cannot establish causation. Higher rates in legal states could reflect better detection, more use, higher potency, or other factors. Hospital discharge codes may not accurately capture cannabis involvement.

Questions This Raises

  • ?Are the higher rates in legal states driven by increased cannabis use, higher potency products, or more clinicians coding cannabis involvement?
  • ?Would longitudinal data show psychosis hospitalizations increasing after legalization?

Trust & Context

Key Stat:
55% higher psychosis hospitalization odds in Pacific division
Evidence Grade:
National database analysis with multivariate adjustment, but cross-sectional design and potential coding variability limit causal inference.
Study Age:
Published in 2022
Original Title:
Geographical variation in hospitalization for psychosis associated with cannabis use and cannabis legalization in the United States: Submit to: Psychiatry Research.
Published In:
Psychiatry research, 308, 114387 (2022)
Database ID:
RTHC-04079

Evidence Hierarchy

Meta-Analysis / Systematic Review
Randomized Controlled Trial
Cohort / Case-Control
Cross-Sectional / ObservationalSnapshot without intervening
This study
Case Report / Animal Study

A snapshot of a population at one point in time.

What do these levels mean? →

Frequently Asked Questions

Does cannabis legalization increase psychosis hospitalizations?

This study found states with more liberal cannabis laws had significantly higher rates of psychosis-related hospitalizations. The Pacific division (mostly legal states) had 55% higher odds, and cannabis legality correlated with hospitalization rates (r=0.67).

How many people are hospitalized for cannabis-related psychosis?

In 2017, there were an estimated 129,070 hospital discharges for psychosis associated with cannabis use in the United States.

Read More on RethinkTHC

Cite This Study

RTHC-04079·https://rethinkthc.com/research/RTHC-04079

APA

Moran, Lauren V; Tsang, Erica S; Ongur, Dost; Hsu, John; Choi, May Y. (2022). Geographical variation in hospitalization for psychosis associated with cannabis use and cannabis legalization in the United States: Submit to: Psychiatry Research.. Psychiatry research, 308, 114387. https://doi.org/10.1016/j.psychres.2022.114387

MLA

Moran, Lauren V, et al. "Geographical variation in hospitalization for psychosis associated with cannabis use and cannabis legalization in the United States: Submit to: Psychiatry Research.." Psychiatry research, 2022. https://doi.org/10.1016/j.psychres.2022.114387

RethinkTHC

RethinkTHC Research Database. "Geographical variation in hospitalization for psychosis asso..." RTHC-04079. Retrieved from https://rethinkthc.com/research/moran-2022-geographical-variation-in-hospitalization

Access the Original Study

Study data sourced from PubMed, a service of the U.S. National Library of Medicine, National Institutes of Health.

This study breakdown was produced by the RethinkTHC research team. We analyze and report published research findings without making health recommendations. All interpretations are based solely on the published abstract and study data.