People With ADHD Start Using Cannabis and Other Drugs Earlier

Adults with ADHD and substance use disorder started using substances at a younger age and had higher rates of cannabis, alcohol, and methamphetamine use compared to those without ADHD.

Vaziri-Harami, Roya et al.·Annals of medicine and surgery (2012)·2024·Moderate EvidenceCross-Sectional
RTHC-05780Cross SectionalModerate Evidence2024RETHINKTHC RESEARCH DATABASErethinkthc.com/research

Quick Facts

Study Type
Cross-Sectional
Evidence
Moderate Evidence
Sample
N=140

What This Study Found

The ADHD group had a lower age of onset for substance use. ADHD individuals had higher rates of alcohol, cannabis, methamphetamine, and tramadol use, while the non-ADHD group had higher rates of Ritalin, methadone, ecstasy, morphine, and hypnotics. The pattern suggests ADHD is associated with earlier initiation and preference for stimulating and cannabis-type substances.

Key Numbers

50 ADHD, 90 non-ADHD. ADHD group: higher alcohol, cannabis, methamphetamine, tramadol. Non-ADHD: higher Ritalin, methadone, ecstasy, morphine, hypnotics. ADHD group started substances earlier.

How They Did This

Longitudinal study of 140 adults (50 with ADHD, 90 without) with substance use disorder in addiction detention in Tehran (2021-2022). ADHD diagnosed via SCID and Conner's questionnaire. Onset age and patterns of 10 substances compared.

Why This Research Matters

The lower age of onset in ADHD has clinical implications: earlier substance initiation is associated with worse long-term outcomes. Identifying ADHD in young people could provide a window for preventive intervention before substance use begins.

The Bigger Picture

ADHD persists into adulthood in 60% of cases and affects 4% of adults. The overlap with substance use disorders suggests shared neurodevelopmental pathways, with impulsivity and sensation-seeking as potential mechanisms driving earlier and broader substance experimentation.

What This Study Doesn't Tell Us

Study conducted in addiction detention, limiting generalizability. Small ADHD sample (n=50). Cross-sectional assessment of retrospectively reported onset ages introduces recall bias. Iranian cultural context may differ from other countries.

Questions This Raises

  • ?Would treating ADHD earlier reduce substance use initiation?
  • ?Why do ADHD individuals prefer different substances than non-ADHD individuals?
  • ?Could cannabis use in ADHD be partly self-medication for attention symptoms?

Trust & Context

Key Stat:
ADHD group started substance use at a younger age
Evidence Grade:
Small clinical sample with validated ADHD diagnosis, but limited by addiction detention setting and retrospective design.
Study Age:
2024 study using 2021-2022 data
Original Title:
Patterns of substance use and initiation timing in adults with substance abuse: a comparison between those with and without attention deficit hyperactivity disorder.
Published In:
Annals of medicine and surgery (2012), 86(8), 4397-4401 (2024)
Database ID:
RTHC-05780

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

Do people with ADHD use more cannabis?

In this study, adults with ADHD had higher rates of cannabis use (and alcohol and methamphetamine) compared to those without ADHD, and they started using substances at a younger age.

Should ADHD be screened in substance use treatment?

This study supports early ADHD screening, as the ADHD group started substances younger and used a broader range of high-risk substances, suggesting ADHD treatment could be an intervention point.

Read More on RethinkTHC

Cite This Study

RTHC-05780·https://rethinkthc.com/research/RTHC-05780

APA

Vaziri-Harami, Roya; Khademi, Mojgan; Zolfaghari, Anahita; Vaziri-Harami, Saharnaz. (2024). Patterns of substance use and initiation timing in adults with substance abuse: a comparison between those with and without attention deficit hyperactivity disorder.. Annals of medicine and surgery (2012), 86(8), 4397-4401. https://doi.org/10.1097/MS9.0000000000002272

MLA

Vaziri-Harami, Roya, et al. "Patterns of substance use and initiation timing in adults with substance abuse: a comparison between those with and without attention deficit hyperactivity disorder.." Annals of medicine and surgery (2012), 2024. https://doi.org/10.1097/MS9.0000000000002272

RethinkTHC

RethinkTHC Research Database. "Patterns of substance use and initiation timing in adults wi..." RTHC-05780. Retrieved from https://rethinkthc.com/research/vaziri-harami-2024-patterns-of-substance-use

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.