Cannabis Users in Brazil Had Three Times the Rate of Suicidal Thoughts as the General Population

In a nationally representative Brazilian survey, cannabis users had markedly elevated rates of suicidal ideation (31.5%) and suicide attempts (16.5%) that remained significant even after controlling for demographics, tobacco use, family history, and depression.

Abdalla, Renata R et al.·Revista brasileira de psiquiatria (Sao Paulo·2019·Moderate EvidenceCross-Sectional
RTHC-01892Cross SectionalModerate Evidence2019RETHINKTHC RESEARCH DATABASErethinkthc.com/research

Quick Facts

Study Type
Cross-Sectional
Evidence
Moderate Evidence
Sample
N=4,607

What This Study Found

Among cannabis users, 31.5% reported suicidal ideation and 16.5% reported suicide attempts, compared to 9.9% and 5.4% in the general sample. After adjusting for demographic characteristics, tobacco use, family history of suicide, and depression, cannabis use remained positively associated with both suicidal ideation and attempts.

Key Numbers

4,607 participants. Cannabis users: 31.5% suicidal ideation (vs 9.9% overall), 16.5% suicide attempts (vs 5.4% overall). Associations remained significant after adjusting for depression, tobacco use, family history, and demographics.

How They Did This

National probability sample survey (II BNADS) of 4,607 Brazilians aged 14+ using multistage cluster design. Self-reported substance use, suicidal ideation, and suicide attempts. Response rate 77%.

Why This Research Matters

The persistence of the cannabis-suicide association after adjusting for depression and other confounders suggests cannabis use may be an independent risk marker for suicidal behavior, warranting screening in cannabis-using populations.

The Bigger Picture

This study from Brazil adds to a growing body of evidence linking cannabis use with suicidal behavior across diverse populations and cultures. The finding that the association persists after controlling for depression is particularly noteworthy.

What This Study Doesn't Tell Us

Cross-sectional design cannot determine causation. Self-reported measures of both substance use and suicidality. Cannabis users may differ from non-users in unmeasured ways. Brazilian context may differ from other countries.

Questions This Raises

  • ?Does cannabis use contribute to suicidal behavior or do shared risk factors explain the association?
  • ?Would cannabis cessation reduce suicide risk?
  • ?Should suicide screening be standard in cannabis use disorder treatment?

Trust & Context

Key Stat:
31.5% of cannabis users reported suicidal ideation vs 9.9% of the general sample; the association persisted after controlling for depression.
Evidence Grade:
Moderate - large nationally representative sample with 77% response rate and multivariable adjustment, but cross-sectional.
Study Age:
Published in 2019.
Original Title:
Suicidal behavior among substance users: data from the Second Brazilian National Alcohol and Drug Survey (II BNADS).
Published In:
Revista brasileira de psiquiatria (Sao Paulo, Brazil : 1999), 41(5), 437-440 (2019)
Database ID:
RTHC-01892

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

Is cannabis use linked to suicide?

This Brazilian national survey found cannabis users had markedly higher rates of suicidal ideation (31.5% vs 9.9%) and suicide attempts (16.5% vs 5.4%). The association remained significant even after accounting for depression, tobacco use, and family history of suicide.

Does depression explain the link between cannabis and suicide?

Not entirely. While depression was also associated with suicidal behavior, the cannabis-suicide association persisted after controlling for depression, demographics, tobacco use, and family history. This suggests cannabis use may be an independent risk marker.

Read More on RethinkTHC

Cite This Study

RTHC-01892·https://rethinkthc.com/research/RTHC-01892

APA

Abdalla, Renata R; Miguel, André C; Brietzke, Elisa; Caetano, Raul; Laranjeira, Ronaldo; Madruga, Clarice S. (2019). Suicidal behavior among substance users: data from the Second Brazilian National Alcohol and Drug Survey (II BNADS).. Revista brasileira de psiquiatria (Sao Paulo, Brazil : 1999), 41(5), 437-440. https://doi.org/10.1590/1516-4446-2018-0054

MLA

Abdalla, Renata R, et al. "Suicidal behavior among substance users: data from the Second Brazilian National Alcohol and Drug Survey (II BNADS).." Revista brasileira de psiquiatria (Sao Paulo, 2019. https://doi.org/10.1590/1516-4446-2018-0054

RethinkTHC

RethinkTHC Research Database. "Suicidal behavior among substance users: data from the Secon..." RTHC-01892. Retrieved from https://rethinkthc.com/research/abdalla-2019-suicidal-behavior-among-substance

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.