People With Inflammatory Bowel Disease Were More Likely to Have Used Cannabis and Started Younger

A national survey found that people with IBD had higher rates of ever using cannabis (67.3% vs. 60%), started using at a younger age, and used more per session than matched controls.

Weiss, Alexandra et al.·Drug and alcohol dependence·2015·Moderate EvidenceCross-Sectional
RTHC-01076Cross SectionalModerate Evidence2015RETHINKTHC RESEARCH DATABASErethinkthc.com/research

Quick Facts

Study Type
Cross-Sectional
Evidence
Moderate Evidence
Sample
Not reported

What This Study Found

Using data from the NHANES national health survey, researchers compared cannabis use patterns between people with inflammatory bowel disease (IBD) and matched controls.

People with IBD were more likely to have ever used cannabis (67.3% vs. 60.0%) and started at a younger average age (15.7 years vs. 19.6 years). When they did use, IBD patients tended to use heavier amounts per session: 64.9% reported three or more joints per day compared to 80.5% of non-IBD subjects using two or fewer.

However, IBD patients were less likely to have used cannabis consistently every month for a year. In regression analysis, having IBD, being male, and being over 40 predicted cannabis use.

Key Numbers

Weighted populations: ~2.08 million IBD subjects, ~2.01 million controls. Ever used cannabis: 67.3% (IBD) vs. 60.0% (controls). Age of first use: 15.7 years (IBD) vs. 19.6 years (controls). 20% of IBD patients had a history of drug or alcohol use disorder.

How They Did This

Cases were identified from the NHANES database (2009-2010) as having ulcerative colitis or Crohn's disease. They were matched with controls using propensity score matching based on age, gender, and sample weighting. After weighting, approximately 2 million subjects per group were represented.

Why This Research Matters

Cannabis use among IBD patients is common but poorly understood. These population-level data suggest that IBD patients may use cannabis differently than the general population, potentially as symptom management, and that older males with IBD are the most likely users.

The Bigger Picture

As interest grows in cannabis as a potential therapy for IBD symptoms, understanding existing use patterns helps frame the conversation. The higher rates and heavier use among IBD patients suggest many are already self-medicating, which underscores the need for clinical research on efficacy and safety.

What This Study Doesn't Tell Us

NHANES relies on self-reported data, which may undercount cannabis use. The cross-sectional design cannot determine whether IBD drives cannabis use or whether cannabis use affects IBD. The 2009-2010 data predate widespread legalization. The study could not assess whether cannabis use improved or worsened IBD outcomes.

Questions This Raises

  • ?Are IBD patients using cannabis specifically for symptom relief?
  • ?Does the earlier age of cannabis onset among IBD patients reflect a biological connection or simply correlation?

Trust & Context

Key Stat:
67.3% of IBD patients had ever used cannabis vs. 60% of controls
Evidence Grade:
This is a large population-based cross-sectional study using NHANES data with propensity score matching, providing moderate-quality evidence on use patterns.
Study Age:
Published in 2015, using 2009-2010 data. Cannabis access and attitudes have changed substantially since then.
Original Title:
Patterns of cannabis use in patients with Inflammatory Bowel Disease: A population based analysis.
Published In:
Drug and alcohol dependence, 156, 84-89 (2015)
Database ID:
RTHC-01076

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

Are people with IBD using cannabis to manage their symptoms?

The study documented use patterns but could not determine motivations. The heavier per-session use and higher overall rates suggest possible symptom management, but this was not directly measured.

Does cannabis help or hurt inflammatory bowel disease?

This study did not assess outcomes. Some other research suggests cannabis may help with IBD symptoms like pain and appetite, but whether it affects the underlying inflammation remains unclear and requires more clinical trials.

Read More on RethinkTHC

Cite This Study

RTHC-01076·https://rethinkthc.com/research/RTHC-01076

APA

Weiss, Alexandra; Friedenberg, Frank. (2015). Patterns of cannabis use in patients with Inflammatory Bowel Disease: A population based analysis.. Drug and alcohol dependence, 156, 84-89. https://doi.org/10.1016/j.drugalcdep.2015.08.035

MLA

Weiss, Alexandra, et al. "Patterns of cannabis use in patients with Inflammatory Bowel Disease: A population based analysis.." Drug and alcohol dependence, 2015. https://doi.org/10.1016/j.drugalcdep.2015.08.035

RethinkTHC

RethinkTHC Research Database. "Patterns of cannabis use in patients with Inflammatory Bowel..." RTHC-01076. Retrieved from https://rethinkthc.com/research/weiss-2015-patterns-of-cannabis-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.