Gluten-Free Diet –Role in IBS?

MI Pinto-Sanchez et al. Clin Gastroenterol Hepatol 2021; 19: 2343-2352. Open Access: Gluten-Free Diet Reduces Symptoms, Particularly Diarrhea, in Patients With Irritable Bowel Syndrome and Antigliadin IgG

In this prospective study of 50 patients with IBS (ROME III, all subtypes), with and without serologic reactivity to gluten (antigliadin IgG and IgA), and 25 healthy subjects (controls) were studied before and after 4 weeks of a GFD. Celiac disease (CD) was ruled out in patients and controls by negative tissue transglutaminase (tTG) IgA antibody and deamidated gliadin IgA or IgG antibodies and by the absence of mucosal atrophy in a duodenal biopsy specimen (Marsh 0 or 1). At least 4 and 2 biopsy specimens were obtained from the second and the first part of the duodenum, respectively.

Key findings:

  • Compared with baseline, IBS symptoms improved in 18 of 24 patients (75%) with antigliadin IgG and IgA and in 8 of 21 patients (38%) without the antibodies
(A) Improvement in IBS symptoms (>4.5 points in the total Birmingham score) in antigliadin antibody (AGA)+ and AGA patients after GFD. (B) Change in IBS symptoms after a gluten-free diet (GFD) compared with baseline in AGA+ and AGA patients.

The associated editorial (A Rej et al. Open Access: Personalizing Dietary Therapies For Irritable Bowel Syndrome: What Is Gluten’s Role?) provides some useful points:

  • “A key trigger for symptom generation in IBS is diet, with more than 80% reporting food-related symptoms…It seems that wheat is a key component for symptom generation in IBS, as demonstrated by a study in 920 patients by Carroccio et al,8 which identified wheat sensitivity in 30% of patients”
  • The authors note that the Pinto-Sanchez population had a higher-than-expected rate of AGA positivity of 50% when previous studies have found rates of 7-18%.

My take: This prospective study indicates that a GFD is associated with clinical improvement in a significant number of individuals with IBS (with and without antigliadin antibodies) who did not report any gluten sensitivity or were not on a gluten-restricted diet before study entry. Based on a number of other studies, however, it seems that a low FODMAPs diet is likely to have a higher efficacy for patients with IBS.

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