One in Four People With HIV Were High Cannabis Users Over a Decade, Linked to Depression and Tobacco

A 10-year study of 3,299 people with HIV identified four cannabis use trajectories: Low/No Use (67%), High Use (26%), Increased (4%), and Decreased (2%), with high use associated with older age, university education, tobacco smoking, and significant depression.

RTHC-06906Longitudinal CohortStrong Evidence2025RETHINKTHC RESEARCH DATABASErethinkthc.com/research

Quick Facts

Study Type
Longitudinal Cohort
Evidence
Strong Evidence
Sample
N=3,299

What This Study Found

Four trajectories: Low/No Use (67%), Increased Use (4%), Decreased Use (2%), High Use (26%). High Use group predictors: older age, university education, tobacco smoking, significant depressive symptoms. The majority (67%) had consistently low or no cannabis use over the decade.

Key Numbers

3,299 participants; 81% male; 57% gay; 58% current/former smokers; 43% significant depression; 26% high use trajectory; 67% low/no use.

How They Did This

Latent class growth analysis of the Ontario HIV Treatment Network Cohort Study (2008-2017). 3,299 participants with interview data over up to 10 years. Chi-square tests for trajectory group predictors.

Why This Research Matters

Cannabis use is common among people with HIV, often for symptom management. Understanding long-term use patterns and their correlates helps clinicians identify who may need intervention and who is using cannabis stably.

The Bigger Picture

The association between high cannabis use and depressive symptoms raises the question of whether cannabis is being used to self-medicate depression or whether heavy use contributes to depressive symptoms. This pre-legalization dataset provides a baseline for tracking post-legalization changes.

What This Study Doesn't Tell Us

Pre-legalization data (2008-2017) may not reflect current patterns. Self-reported cannabis use. Observational design cannot determine depression-cannabis directionality. Ontario cohort may not generalize.

Questions This Raises

  • ?Did cannabis legalization in 2018 change use trajectories among PWH?
  • ?Is the depression-cannabis association causal in either direction?

Trust & Context

Key Stat:
26% of people with HIV were in the High Use trajectory
Evidence Grade:
Large cohort with decade-long follow-up and sophisticated trajectory analysis. Pre-legalization timeframe may limit current relevance.
Study Age:
2025 publication analyzing 2008-2017 pre-legalization data from Ontario.
Original Title:
Cannabis Use Trajectories Among People Living With HIV in the Decade Prior to Recreational Legalization in Ontario, Canada (2008-2017).
Published In:
AIDS education and prevention : official publication of the International Society for AIDS Education, 37(2), 142-159 (2025)
Database ID:
RTHC-06906

Evidence Hierarchy

Meta-Analysis / Systematic Review
Randomized Controlled Trial
Cohort / Case-ControlFollows or compares groups over time
This study
Cross-Sectional / Observational
Case Report / Animal Study

Follows a group of people over time to track how outcomes develop.

What do these levels mean? →

Frequently Asked Questions

How common is cannabis use among people with HIV?

In this Ontario cohort, 26% were consistently high users over a decade, while 67% had consistently low or no use.

Why do people with HIV use cannabis?

This study found high use was linked to depressive symptoms, suggesting self-medication may play a role, though the direction of causation is unclear.

Read More on RethinkTHC

Cite This Study

RTHC-06906·https://rethinkthc.com/research/RTHC-06906

APA

Lazor, Tanya; Sanches, Marcos; Wardell, Jeffrey D; Wang, Wei; Burchell, Ann N; Margolese, Shari; Bekele, Tsegaye; Kroch, Abigail E; Rueda, Sergio. (2025). Cannabis Use Trajectories Among People Living With HIV in the Decade Prior to Recreational Legalization in Ontario, Canada (2008-2017).. AIDS education and prevention : official publication of the International Society for AIDS Education, 37(2), 142-159. https://doi.org/10.1521/aeap.2025.37.2.142

MLA

Lazor, Tanya, et al. "Cannabis Use Trajectories Among People Living With HIV in the Decade Prior to Recreational Legalization in Ontario, Canada (2008-2017).." AIDS education and prevention : official publication of the International Society for AIDS Education, 2025. https://doi.org/10.1521/aeap.2025.37.2.142

RethinkTHC

RethinkTHC Research Database. "Cannabis Use Trajectories Among People Living With HIV in th..." RTHC-06906. Retrieved from https://rethinkthc.com/research/lazor-2025-cannabis-use-trajectories-among

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.