Answering Questions About a Gluten-Free Diet

Prevalence of Gluten-Free Diet and Symptom Improvement in Patients with Inflammatory Bowel Diseases in CCFA Partners Cohort: A Poster Session at AIBD 2013. Presenter: Hans Herfarth, University of North Carolina Chapel Hill

Patients with inflammatory bowel disease (IBD) may be intimidated by their gastroenterologists and avoid mentioning that they’re on a gluten-free diet. So, it’ll probably fall on primary care to field the questions: Doctor, will it improve my IBD?

Some of the more irresponsible books and Web sites have already claimed that it is curative. No well-designed study to date has identified any significant benefit. But the current study reported in this poster session suggests that many patients who try it believe that it works.

Although placebo effect cannot be controlled here, the study is provocative because it shows us that we need to ask about gluten-free diet because so many patients are trying this diet. We need to know, if for no other reason than to ensure that they’re getting adequate nutrition (many currently marketed gluten-free foods are high in white flours and sweeteners).

The methodology is severely limited. It’s strictly a questionnaire-based study of 1647 patients with confirmed IBD participating in the Crohn’s and Colitis Foundation of America’s CCFA Partners program, a longitudinal, internet-based cohort study-so this is self-report only-of diagnosis, treatment, and outcomes, without validation by manual or electronic review of records.

Patients were asked about gluten-related illnesses, whether they followed a gluten-free diet, and whether gluten affected GI symptoms or flares. Current gluten-free dieters were given a validated gluten-free diet adherence questionnaire.

Ten patients (0.6%) reported that they had received a diagnosis of celiac disease, and 81 (4.9%) reported that they had received a diagnosis of “gluten sensitivity” (a condition that does not yet have diagnostic criteria); 314 (19.1%) reported ever having followed a gluten-free diet, and 135 (8.2%) were currently on it. No differences were found between dieters and nondieters with regard to disease type, disease duration, or educational status.

Of the patients trying a gluten-free diet, 66% reported improvement in GI symptoms; 38.3% thought they had fewer and less severe flares on the diet, and 23.6% reported requiring less medication. Diet adherence was found to be excellent in only 42% of those saying they were on it (which suggests at least some role for placebo here).

The question for primary care physicians and specialists is not whether gluten is implicated in the pathogenesis of IBD-this study cannot make that claim. But, it clearly shows us something we aren’t thinking about today. Patients with IBD are trying gluten-free diets in great numbers, and-by a 2-to-1 margin-they think it helps.

The results suggest that the so-called gluten-free lifestyle is going to be part of our IBD patient’s lives in the years to come, and we can’t rule out some benefit to it. Regardless of what the science shows (or doesn’t show): when patients with IBD see you, ask about diet.