Cannabis Use in Patients with Inflammatory Bowel Disease Following Legalization of Cannabis in Canada

Background: Cannabis is used by patients with Crohn's disease (CD) and ulcerative colitis (UC) as an alternative to, or in combination with, conventional therapies to treat symptoms such as abdominal pain, poor sleep, and reduced appetite. The clinical efficacy of cannabis for these disorders is controversial, with some studies showing harmful outcomes associated with its use. Previous studies suggest that cannabis is used by similar to 12% of patients with UC and similar to 16% of patients with CD in the USA despite legal prohibition. Methods: We conducted a prospective cohort study of adult patients with inflammatory bowel diseases (IBD) followed in a Canadian tertiary care center. Patients completed an online 40-question survey that included demographics, IBD disease history, cannabis use, and the Short Inflammatory Bowel Disease Questionnaire (SIBDQ). Results: Completed surveys were obtained from 254 participants (148 with CD, 90 with UC, and 16 with indeterminate colitis). Recent cannabis use was reported by 41% of CD and 31% of UC participants. Interestingly, only 46% of participants who used cannabis discussed their use with their physician. Participants who recently used cannabis reported more abdominal pain, poor appetite, and flatulence, and importantly this was associated with lower SIBDQ scores (recent use 37 vs non-recent use 40). Conclusions: Cannabis use among patients with IBD has more than doubled since its legalization. Cannabis use is associated with worse abdominal symptoms and quality of life. Physicians should inquire about cannabis use and optimize symptom control with evidence-based therapies. In a Canadian prospective cohort study, findings determined that cannabis use among IBD patients has increased since its legalization, oftentimes without their physician's knowledge. The study found cannabis use increased or worsened abdominal symptoms and quality of life.