title: A study evaluating the bidirectional relationship between inflammatory bowel disease and self-reported non-celiac gluten sensitivity.
abstract: BACKGROUND
  Non-celiac gluten sensitivity and the associated use of a gluten-free diet (GFD) are perceived to belong to the spectrum of irritable bowel syndrome (IBS). However, recent reports suggest substantial use of a GFD in inflammatory bowel disease (IBD). We assessed the bidirectional relationship between IBD and self-reported non-celiac gluten sensitivity (SR-NCGS).
  
  
  METHODS
  A cross-sectional questionnaire screened for SR-NCGS and the use of a GFD in 4 groups: ulcerative colitis (n = 75), Crohn's disease (n = 70), IBS (n = 59), and dyspeptic controls (n = 109). We also assessed diagnostic outcomes for IBD in 200 patients presenting with SR-NCGS.
  
  
  RESULTS
  The prevalence of SR-NCGS was 42.4% (n = 25/59) for IBS, followed by 27.6% (n = 40/145) for IBD, and least among dyspeptic controls at 17.4% (n = 19/109); P = 0.015. The current use of a GFD was 11.9% (n = 7/59) for IBS, 6.2% (n = 9/145) for IBD, and 0.9% (1/109) for dyspeptic controls; P = 0.02. No differences were established between ulcerative colitis and Crohn's disease. However, Crohn's disease patients with SR-NCGS were significantly more likely to have stricturing disease (40.9% versus 18.9%, P = 0.046), and higher mean Crohn's Disease Activity Index score (228.1 versus 133.3, P = 0.002), than those without SR-NCGS. Analysis of 200 cases presenting with SR-NCGS suggested that 98.5% (n = 197) could be dietary-related IBS. However, 1.5% (n = 3) were found to have IBD; such patients had associated alarm symptoms, and/or abnormal blood parameters, prompting colonic investigations.
  
  
  CONCLUSIONS
  SR-NCGS is not only exclusive to IBS but also associated with IBD, where its presence may be reflecting severe or stricturing disease. Randomized studies are required to further delineate the nature of this relationship and clarify whether a GFD is a valuable dietetic intervention in selected IBD patients.
authors.affiliation: *Department of Gastroenterology, Royal Hallamshire Hospital, Sheffield Teaching Hospitals, Sheffield, United Kingdom; and †Gastroenterology and Endoscopy Unit, Department of Pathophysiology and Transplantation, Fondazione IRCCS Cà Granda Ospedale Maggiore Policlinico, Department of Pathophysiology and Transplant, Università degli Studi di Milano, Milan, Italy.
authors.forename: Imran
authors.initials: I
authors.lastname: Aziz
authors.forename: Federica
authors.initials: F
authors.lastname: Branchi
authors.forename: Katherine
authors.initials: K
authors.lastname: Pearson
authors.forename: Josephine
authors.initials: J
authors.lastname: Priest
authors.forename: David S
authors.initials: DS
authors.lastname: Sanders
mesh_terms: D000328:Adult; D000368:Aged; D002446:Celiac Disease / Q000453:epidemiology*; D003093:Colitis, Ulcerative / Q000453:epidemiology; D003424:Crohn Disease / Q000453:epidemiology; D003430:Cross-Sectional Studies; D055050:Diet, Gluten-Free / Q000706:statistics & numerical data*; D004415:Dyspepsia / Q000150:complications*; D005260:Female; D005983:Glutens / Q000009:adverse effects; D006801:Humans; D015212:Inflammatory Bowel Diseases / Q000453:epidemiology*; D043183:Irritable Bowel Syndrome / Q000453:epidemiology; D008297:Male; D008875:Middle Aged; D015995:Prevalence; D057566:Self Report; D012720:Severity of Illness Index; D011795:Surveys and Questionnaires
chemical_list: D005983:Glutens