FODMAP meal challenge test: a novel investigation to predict response to low‐FODMAP diet in non‐constipating irritable bowel syndrome

Abstract

BackgroundThough a low‐FODMAP diet improves 50% irritable bowel syndrome (IBS) patients, regional dietary variations, vegetarianism, and long‐term nutritional consequences challenge its implementation. We aimed developing a FODMAP meal challenge test (FMCT). We prospectively studied whether (i) high‐ than low‐FODMAP foods produce more breath H2 among IBS patients than controls; (ii) post‐meal symptoms relate to breath H2; and (iii) novel FMCT predicts response to a low‐FODMAP diet?MethodsForty Rome III IBS and 20 healthy controls underwent an eight‐hour H2 breath test following a low‐ (rice, brinjal, corn, and banana [450 Kcal]) and a high‐FODMAP meal (wheat, kidney bean, pulse, and card [450 Kcal]). Breath H2 (every 15 min) and symptoms following low‐ and high‐FODMAP meals were recorded. IBS‐symptom severity scores were recorded every month for 3‐months on low‐FODMAP diet.ResultsForty Rome III IBS (19 Rome IV positive) were comparable to 20 controls in age and gender. IBS patients (n = 39 excluding one H2 non‐producer) and controls produced more breath H2 after high‐ (greater in IBS) than low‐FODMAP meal. Post‐meal symptoms were commoner in IBS (4/40 [10%] and 27/40 [67.5%] with low‐ and high‐FODMAP, respectively [P < 0.00001]; none in healthy). IBS patients developing post‐high‐FODMAP meal symptoms produced greater H2 (18 PPM [IQR 10.5–23] vs 6 [0–7.2]; P < 0.001). A positive FMCT (breath H2 > 10 PPM above basal with symptoms following high‐FODMAP food) had sensitivity, specificity, and diagnostic accuracy of 78.6%, 66.6%, and 75.6%, respectively, to predict low‐FODMAP diet response.ConclusionsThe novel FMCT predicts response to a low‐FODMAP diet in IBS.

The Role of the FODMAP Diet in IBS

“…In a recent limited pilot investigation, the positive FODMAP meal challenge test (indicated by breath H2 levels exceeding 10 PPM above baseline accompanied by symptoms after consuming a high FODMAP meal) demonstrated sensitivity, specificity, and diagnostic accuracy of 78.6%, 66.6%, and 75.6%, respectively, in forecasting the response to a low FODMAP diet [121].…”

Predicting Response to Low Fermentable Oligo-, Di-, Mono-saccharides, and Polyols Diet in Patients With Abdominal Bloating Using Hydrogen Methane Breath Test: Is a Spot Sample Enough?

“…The sensitivity observed by Somvanapanich et al 1 (66.7%) is lower than our study (78%). 4 The above-mentioned factors might explain the difference in sensitivity in these 2 studies. 1 , 4 We believe that studying breath H 2 over a longer duration along with symptoms generation is expected to predict microbial metabolic index in the gut lumen and visceral hypersensitivity to predict response to a low-FODMAP meal as reported by us recently.…”

“… 3 In our recent study on FODMAP-meal challenge test, we observed that rise in breath H 2 was most prominent after the first 4 hours of ingestion of a standardized high FODMAP meal. 4 Somvanapanich et al 1 claimed that they replicated their previous protocol wherein, rise in breath H 2 was not observed after breakfast until 2 hours post-lunch. 5 However, it raises a question whether 2-hour post-lunch rise is exclusively attributed to lunch and not influenced by the breakfast.…”