Young adults with ADHD had significantly higher rates of cannabis and other substance use disorders

In a nationally representative Canadian survey, young adults with ADHD had 46% higher odds of cannabis use disorder, with one in three having a lifetime alcohol use disorder compared to one in five without ADHD.

Fuller-Thomson, Esme et al.·Alcohol and alcoholism (Oxford·2022·Moderate EvidenceCross-Sectional
RTHC-03854Cross SectionalModerate Evidence2022RETHINKTHC RESEARCH DATABASErethinkthc.com/research

Quick Facts

Study Type
Cross-Sectional
Evidence
Moderate Evidence
Sample
N=6,872

What This Study Found

After adjusting for sociodemographics, childhood adversities, and mental health, young adults with ADHD had higher odds of alcohol use disorders (OR 1.38), cannabis use disorders (OR 1.46), other drug use disorders (OR 2.07), and any substance use disorder (OR 1.69). Depression and anxiety history explained the largest portion of the ADHD-substance use disorder relationship.

Key Numbers

6,872 respondents aged 20-39. 270 with ADHD. Alcohol use disorder: 36% of ADHD vs 19% without. Cannabis use disorder OR 1.46. Other drug use disorder OR 2.07. Depression and anxiety were the strongest mediators.

How They Did This

Secondary analysis of the nationally representative Canadian Community Health Survey-Mental Health (6,872 respondents aged 20-39, including 270 with ADHD). Substance use disorders diagnosed using WHO CIDI criteria. ADHD based on self-reported professional diagnosis.

Why This Research Matters

Understanding that ADHD significantly increases substance use disorder risk, particularly through depression and anxiety pathways, can help target prevention efforts.

The Bigger Picture

The finding that depression and anxiety mediate much of the ADHD-substance use relationship suggests that treating psychiatric comorbidities in ADHD may help prevent substance use disorders.

What This Study Doesn't Tell Us

Cross-sectional design cannot establish temporal order. ADHD based on self-reported diagnosis, not standardized assessment. Canadian population may not generalize to other countries.

Questions This Raises

  • ?Would treating depression and anxiety in ADHD patients reduce their substance use disorder risk?
  • ?Are specific ADHD subtypes more vulnerable to cannabis use disorder?

Trust & Context

Key Stat:
36% of young adults with ADHD had lifetime alcohol use disorder vs 19% without
Evidence Grade:
Nationally representative survey with validated diagnostic criteria, though cross-sectional design limits causal inference.
Study Age:
Published in 2022.
Original Title:
Attention-Deficit/Hyperactivity Disorder and Alcohol and Other Substance Use Disorders in Young Adulthood: Findings from a Canadian Nationally Representative Survey.
Published In:
Alcohol and alcoholism (Oxford, Oxfordshire), 57(3), 385-395 (2022)
Database ID:
RTHC-03854

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

Why are people with ADHD more vulnerable to substance use disorders?

The study found that depression and anxiety history explained the largest portion of the increased risk, followed by childhood adversities and socioeconomic status, suggesting these co-occurring conditions drive much of the vulnerability.

How much higher was the cannabis use disorder risk?

Young adults with ADHD had 46% higher odds of developing a cannabis use disorder (OR 1.46) after adjusting for multiple factors including demographics, childhood adversity, and mental health.

Read More on RethinkTHC

Cite This Study

RTHC-03854·https://rethinkthc.com/research/RTHC-03854

APA

Fuller-Thomson, Esme; Lewis, Danielle A; Agbeyaka, Senyo. (2022). Attention-Deficit/Hyperactivity Disorder and Alcohol and Other Substance Use Disorders in Young Adulthood: Findings from a Canadian Nationally Representative Survey.. Alcohol and alcoholism (Oxford, Oxfordshire), 57(3), 385-395. https://doi.org/10.1093/alcalc/agab048

MLA

Fuller-Thomson, Esme, et al. "Attention-Deficit/Hyperactivity Disorder and Alcohol and Other Substance Use Disorders in Young Adulthood: Findings from a Canadian Nationally Representative Survey.." Alcohol and alcoholism (Oxford, 2022. https://doi.org/10.1093/alcalc/agab048

RethinkTHC

RethinkTHC Research Database. "Attention-Deficit/Hyperactivity Disorder and Alcohol and Oth..." RTHC-03854. Retrieved from https://rethinkthc.com/research/fuller-thomson-2022-attentiondeficithyperactivity-disorder-and-alcohol

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.