Cannabis use among IBD patients more than doubled after Canadian legalization | Research

The takeaway

In a Canadian tertiary care center, 41% of Crohn's disease and 31% of ulcerative colitis patients reported recent cannabis use, rates that have more than doubled since legalization, yet cannabis users had worse symptoms and quality of life.

Gastroenterologists, IBD patients, and cannabis policy researchers

41% of Crohn's patients using cannabis post-legalization

What the researchers found

Recent cannabis use was reported by 41% of Crohn's disease patients and 31% of ulcerative colitis patients, more than double pre-legalization rates of ~16% and ~12% respectively. Cannabis users reported more abdominal pain, poor appetite, and flatulence, with lower quality of life scores (SIBDQ 37 vs 40). Less than half (46%) discussed cannabis with their physician.

Why it matters

The dramatic increase in cannabis use among IBD patients after legalization, combined with worse symptoms in users and low rates of physician discussion, represents a clinical blind spot.

The numbers in context

254 participants (148 CD, 90 UC, 16 indeterminate); 41% CD and 31% UC recent cannabis use; pre-legalization rates ~16% CD and ~12% UC; cannabis users SIBDQ 37 vs non-users 40; only 46% discussed with physician

How the study worked

Prospective cohort study of 254 IBD patients at a Canadian tertiary care center who completed online surveys covering demographics, disease history, cannabis use, and the Short IBD Questionnaire (SIBDQ).

What this study cannot tell us

Cross-sectional design cannot determine causation; tertiary care center patients may have more severe disease; self-reported cannabis use; pre-legalization comparison from different study populations; no data on cannabis type, dose, or frequency

How to read the evidence

Single-center prospective survey with validated quality of life measure, but cross-sectional design and tertiary care setting limit generalizability.

When this study was published

2024 study

The bigger picture

The finding that cannabis users had worse symptoms and quality of life, despite using cannabis ostensibly for symptom relief, raises questions about whether cannabis is genuinely helping or whether sicker patients are simply more likely to try it.

Questions still open

Are IBD patients using cannabis because their symptoms are worse, or is cannabis contributing to worse symptoms? Would structured cannabis counseling by gastroenterologists improve outcomes?

Common questions

How much did IBD cannabis use increase after legalization?

Cannabis use roughly doubled or more: 41% of Crohn's disease patients and 31% of ulcerative colitis patients reported recent use, compared to pre-legalization estimates of about 16% for CD and 12% for UC from US studies.

Did cannabis help IBD symptoms?

Cannabis users actually reported worse outcomes: more abdominal pain, poor appetite, and flatulence, along with lower quality of life scores. However, this could reflect sicker patients being more likely to try cannabis rather than cannabis causing the symptoms. Only 46% of users discussed cannabis with their doctor.

Read the original research

Cannabis Use in Patients With Inflammatory Bowel Disease Following Legalization of Cannabis in Canada.

Crohn's & colitis 360, 6(2), otae031

View on PubMed ↗Publisher’s paper ↗

Citation

Iablokov, Vadim; Gregor, Jamie; Chande, Nilesh; Ponich, Terry; Jairath, Vipul; Khanna, Reena; Asfaha, Samuel. (2024). Cannabis Use in Patients With Inflammatory Bowel Disease Following Legalization of Cannabis in Canada.. Crohn's & colitis 360, 6(2), otae031. https://doi.org/10.1093/crocol/otae031