IgG-Based Elimination Diets Reduce IBS Abdominal Pain, Bloating

Elimination diets based on immunoglobulin G (IgG)-confirmed food sensitivities effectively reduce abdominal pain, bloating, and overall symptoms in patients with irritable bowel syndrome (IBS), according to study results presented at the American College of Gastroenterology (ACG) 2022 Annual Meeting, held from October 21 to 26, 2022, in Charlotte, North Carolina, and virtually.

Researchers conducted a prospective, multicenter, double-blind, placebo-controlled study, analyzing the effectiveness of elimination diets in relieving symptoms of IBS in 223 patients treated for IBS in 6 centers in the United States.

Included patients reported an average daily abdominal pain intensity of 3 up to 7.5 on a 10-point scale. The patients also tested positive for at least 1 food sensitivity or intolerance on the IgG panel, although the researchers commented on the controversial nature of identifying patients with food sensitivities using IgG antibodies.

Patients randomly assigned to the treatment group eliminated foods for which they tested positive on the IgG panel for 8 weeks, while patients in the placebo group eliminated foods on the panel for which they tested negative.

Daily self-reported assessments included bowel habits, bloating, and abdominal pain intensity. Weekly assessments included the Global Improvement Scale (GIS), the Subject Global Assessment of Relief (SGA), and IBS Adequate Relief (AR).

Abdominal pain intensity and bloating decreased more in patients with IBS on active elimination diets compared with patients on sham elimination diets; however, these changes did not achieve statistical significance (P =.0718 and P =.0827, respectively).

In contrast, patients in the treatment group demonstrated significant improvements in overall global symptoms compared with the sham treatment group, according to changes in both GIS (P =.0302) and SGA scores (P =.0093).

When analyzing the different IBS subgroups as classified using the Rome IV diagnostic criteria, the researchers observed that patients with IBS subtypes (n=149) other than the subtype causing diarrhea demonstrated the largest improvements from baseline measurements in abdominal pain intensity (P =.0139), bloating (P =.0214), and global symptoms (P =.0020 for and P =.0010 for SGA). This finding suggested that patients with specific IBS subtypes responded better to elimination diets than others.

“These results suggest that IgG-based elimination diets using a novel, proprietary diagnostic to guide therapy may offer benefit to patients with IBS,” the study authors said.

Disclosure: Some study authors declared affiliations with biotech, pharmaceutical, and/or device companies. Please see the original reference for a full list of authors’ disclosures.