title: Cannabis use provides symptom relief in patients with inflammatory bowel disease but is associated with worse disease prognosis in patients with Crohn's disease.
abstract: BACKGROUND
  Cannabinoids are used by patients with inflammatory bowel disease (IBD) to alleviate their symptoms. Little is known on patient motivation, benefit, or risks of this practice. Our aim was to assess the extent and motives for Cannabis use in patients with IBD and the beneficial and adverse effects associated with self-administration of Cannabis.
  
  
  METHODS
  Consecutive patients with IBD (n = 313) seen in the University of Calgary from July 2008 to March 2009 completed a structured anonymous questionnaire covering motives, pattern of use, and subjective beneficial and adverse effects associated with self-administration of Cannabis. Subjects who had used Cannabis specifically for the treatment of IBD or its symptoms were compared with those who had not. Logistic regression analysis was used to identify variables predictive of poor IBD outcomes, specifically surgery or hospitalization for IBD.
  
  
  RESULTS
  Cannabis had been used by 17.6% of respondents specifically to relieve symptoms associated with their IBD, the majority by inhalational route (96.4%). Patients with IBD reported that Cannabis improved abdominal pain (83.9%), abdominal cramping (76.8%), joint pain (48.2%), and diarrhea (28.6%), although side effects were frequent. The use of Cannabis for more than 6 months at any time for IBD symptoms was a strong predictor of requiring surgery in patients with Crohn's disease (odds ratio = 5.03, 95% confidence interval = 1.45-17.46) after correcting for demographic factors, tobacco smoking status, time since IBD diagnosis, and biological use. Cannabis was not a predictor for hospitalization for IBD in the previous year.
  
  
  CONCLUSIONS
  Cannabis use is common in patients with IBD and subjectively improved pain and diarrheal symptoms. However, Cannabis use was associated with higher risk of surgery in patients with Crohn's disease. Patients using Cannabis should be cautioned about potential harm, until clinical trials evaluate efficacy and safety.
authors.affiliation: *Division of Gastroenterology, Department of Medicine, University of Calgary and; †Division of Gastroenterology, Department of Medicine, University of Munich.
authors.forename: Martin
authors.initials: M
authors.lastname: Storr
authors.forename: Shane
authors.initials: S
authors.lastname: Devlin
authors.forename: Gilaad G
authors.initials: GG
authors.lastname: Kaplan
authors.forename: Remo
authors.initials: R
authors.lastname: Panaccione
authors.forename: Christopher N
authors.initials: CN
authors.lastname: Andrews
mesh_terms: D000328:Adult; D002188:Cannabis; D003093:Colitis, Ulcerative / Q000188:drug therapy*; D003424:Crohn Disease / Q000188:drug therapy*; D004363:Drug Utilization / Q000706:statistics & numerical data*; D005260:Female; D005500:Follow-Up Studies; D006760:Hospitalization / Q000706:statistics & numerical data*; D006801:Humans; D008297:Male; D016017:Odds Ratio; D008517:Phytotherapy / Q000379:methods / Q000706:statistics & numerical data*; D012720:Severity of Illness Index; D011795:Surveys and Questionnaires; D062606:Tertiary Care Centers; D016896:Treatment Outcome