What topics does this cannabis study cover?

This study covers research on: Mental Health, Addiction.

Where was this research published?

Published in Psychological medicine on September 24, 2026.

Meta-analysis links cannabis use with higher violence risk

Q: What did this Review find?

Across **63 studies involving 265,079 people**, cannabis use was associated with a significantly higher risk of perpetrating violence in both psychiatric and general-population groups.

Cannabis use is associated with increased risk of violence: A systematic review and meta-analysis.

Psychological medicine • September 24, 2026 • Review • Highly Relevant

🤖

AI Summary

This systematic review and meta-analysis examined whether cannabis use is associated with violence, either as perpetration or victimization. It combined evidence from 63 peer-reviewed studies involving 265,079 people, including psychiatric patients and people from the general population. Across the studies, cannabis users had a significantly higher likelihood of perpetrating violence in both groups, with the association also present in longitudinal and cross-sectional research designs.

The strongest associations involved violence resulting in a criminal conviction. Cannabis use was also associated with a higher risk of becoming a victim of violence, particularly among females and mixed-gender groups compared with males. These findings indicate an association, not proof that cannabis use directly causes violence: the abstract does not establish that cannabis was the cause of violent behavior, nor does it identify which patterns of use or other factors explain the relationship. This is an abstract-based summary; the most consequential limitation is that the review synthesizes observational evidence with potential confounding and cannot establish causation.

💡 Key Findings

Across 63 studies involving 265,079 people, cannabis use was associated with a significantly higher risk of perpetrating violence in both psychiatric and general-population groups.

High

90%

The association was especially strong for violence involving a criminal conviction in both general and psychiatric populations.

High

90%

Cannabis use was associated with a higher risk of becoming a victim of violence, with the relationship more pronounced in females and mixed-gender cohorts than in males.

High

90%

Because this was a meta-analysis of existing studies, the findings show association rather than causation and cannot determine whether cannabis use directly produces violent behavior.

High

95%

📄 Original Abstract

Cannabis use is a known risk factor for adverse mental health outcomes, including psychosis, which is frequently associated with aggression. However, the specific impact of cannabis use on the risk of violence remains unclear. This meta-analysis, conducted according to PRISMA guidelines, synthesized evidence from 63 peer-reviewed studies (N = 265,079) identified via MEDLINE, EMBASE, and PsycINFO searches up to November 2024 to clarify the link between cannabis use and violence, either as a perpetrator or as a victim. Random-effects models revealed that cannabis users are at a significantly higher risk of perpetrating violent acts. This association was observed in both psychiatric patients (OR 2.49, 95% CI 1.72-3.61) and the general population (OR 2.05, 95% CI 1.74-2.41), and remained significant across both longitudinal (OR 1.17, 95% CI 1.07-1.28) and cross-sectional (OR 2.37, 95% CI 1.66-3.40) study designs. There was an especially large effect for violence involving a criminal conviction in both general (OR 3.75, 95% CI 2.54-5.53) and psychiatric (OR 4.21, 95% CI 2.86-6.22) populations. Furthermore, cannabis use was significantly associated with an increased risk of becoming a victim of violence (OR 1.49, 95% CI 1.38-1.60), a risk more pronounced in females and mixed-gender cohorts compared to males. This meta-analysis indicates an increased risk of violence, especially that resulting in a criminal conviction, among cannabis users. It also highlights the potential of cannabis use as a target for interventions to decrease violence, and underscores the need for routine assessment of cannabis use among psychiatric patients.

Paper Type

📚 Review

Publication

Journal: Psychological medicine
Published: September 24, 2026
PMID: 42779465
DOI: 10.1017/S0033291726105856

Authors (10)

Giulia Trotta SGDP: King's College London Social Genetic & Developmental Psychiatry Centre, UK.
Victoria Rodriguez Department of Psychosis Studies, Institute of Psychiatry, Psychology & Neuroscience, King's College London, London, UK.
Paolo Marino Department of Psychosis Studies, Institute of Psychiatry, Psychology & Neuroscience, King's College London, London, UK.
Meklit Gurmesa SGDP: King's College London Social Genetic & Developmental Psychiatry Centre, UK.
Edoardo Spinazzola South London and Maudsley NHS Foundation Trust, London, UK.
+5 more authors