Cannabis Use Linked to Higher Odds of Suicide Death in National Case-Control Study

After adjusting for alcohol and demographics, cannabis use was associated with 83% increased odds of suicide death in a national dataset.

Shi, Qiongyu et al.·Journal of cannabis research·2025·Moderate EvidenceObservational
RTHC-07642ObservationalModerate Evidence2025RETHINKTHC RESEARCH DATABASErethinkthc.com/research

Quick Facts

Study Type
Observational
Evidence
Moderate Evidence
Sample
Not reported

What This Study Found

Toxicology-verified cannabis use was associated with 83% increased odds of suicide (aOR 1.83, 95% CI: 1.36-2.31), independent of alcohol use, which showed a 20-fold increase in suicide odds.

Key Numbers

17.1% of suicide cases tested positive for THC compared to 7.2% of controls. Cannabis aOR for suicide: 1.83. Alcohol aOR for suicide: 20.53. Other risk factors included male sex, White race, ages 35-49, and less than high school education.

How They Did This

Case-control study using 2013 National Violent Death Reporting System suicide decedents as cases and 2013 NSDUH respondents as controls, with data fusion from the 2013 National Roadside Survey to correct for self-report misclassification. Weighted multivariable logistic regression estimated adjusted odds ratios.

Why This Research Matters

Most research on cannabis and suicide focuses on ideation or attempts. This study directly examined completed suicide deaths using toxicological verification rather than self-report, addressing a significant gap in the literature.

The Bigger Picture

While this study found an association between cannabis use and suicide, the cross-sectional design cannot establish causation. The alcohol association was dramatically larger (20-fold vs. 83%), and unmeasured confounders like mental health diagnoses were not fully accounted for.

What This Study Doesn't Tell Us

Cross-sectional case-control design prevents causal conclusions. Controls were from a general population survey while cases were suicide decedents, creating potential selection bias. Mental health conditions were not included as covariates. THC positivity indicates recent use but not frequency or dose.

Questions This Raises

  • ?Does the association hold when controlling for diagnosed mental health conditions?
  • ?What role does frequency and dose of cannabis use play in suicide risk?

Trust & Context

Key Stat:
Evidence Grade:
Large national datasets with toxicological verification strengthen the findings, but the case-control design, potential confounders, and inability to establish causation limit evidence to moderate.
Study Age:
Uses 2013 data from three national databases.
Original Title:
Cannabis use and suicide: a case-control study based on integrative data analysis.
Published In:
Journal of cannabis research, 7(1), 93 (2025)
Database ID:
RTHC-07642

Evidence Hierarchy

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

Watches what happens naturally without intervening.

What do these levels mean? →

Frequently Asked Questions

Does this prove cannabis causes suicide?

No. This is a case-control study showing an association, not causation. Unmeasured factors like mental health diagnoses could explain some of the relationship.

How does the cannabis risk compare to alcohol?

Alcohol showed a dramatically larger association with suicide (20-fold increased odds) compared to cannabis (83% increased odds).

Read More on RethinkTHC

Cite This Study

RTHC-07642·https://rethinkthc.com/research/RTHC-07642

APA

Shi, Qiongyu; Li, Guohua. (2025). Cannabis use and suicide: a case-control study based on integrative data analysis.. Journal of cannabis research, 7(1), 93. https://doi.org/10.1186/s42238-025-00352-1

MLA

Shi, Qiongyu, et al. "Cannabis use and suicide: a case-control study based on integrative data analysis.." Journal of cannabis research, 2025. https://doi.org/10.1186/s42238-025-00352-1

RethinkTHC

RethinkTHC Research Database. "Cannabis use and suicide: a case-control study based on inte..." RTHC-07642. Retrieved from https://rethinkthc.com/research/shi-2025-cannabis-use-and-suicide

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.