Predictors of response to a dietary intervention in patients with irritable bowel syndrome.

BACKGROUND

Different diets have emerged as potential therapeutic options for patients with irritable bowel syndrome (IBS).

OBJECTIVE

To identify predictors of improvement after a low-FODMAP, low-starch and low-sucrose diet among patients with IBS.

METHODS

We performed a descriptive cross-sectional study including patients with IBS according to Rome IV criteria undertaking a social-media based program with a two-week dietary intervention. Patients completed an online survey before and after the intervention including the presence of intestinal and extra-intestinal symptoms, the IBS-SSS (irritable bowel syndrome symptoms severity scale) and the PHQ-9 (patient health questionnaire-9). Clinical improvement was defined as a decrease of at least 50% in IBS-SSS post dietary intervention. Variables associated with symptomatic response were identified with logistic regression analysis. A clinical score to predict response was created and tested with a with a receiver operating characteristic (ROC) curve analysis.

RESULTS

A total of 3583 patients with IBS were included. Mean IBS-SSS before and after dietary intervention was 295.5±52.32 and 240±48.66, respectively (p=0.01); 1178 (32.8%) patients showed clinical improvement. A mean basal IBS-SSS >400 (OR 3.04), chronic headache (OR 1.96), and chronic fatigue (OR 1.81) were significantly associated with symptomatic response. Patients with arthralgia (OR 0.41) and/or fibromyalgia (OR 0.33) were less likely to improve. Each variable received the following individuals scores: IBS-SSS >400: +2, chronic headache: +1.5, chronic fatigue: +1, arthralgia: -1, and fibromyalgia: -1. The ROC curve analysis of the proposed score showed an area under the curve of 0.72 (95% CI 0.69-0.76). A score ≥3 had a sensitivity of 72.64% and specificity of 60.56% for predicting symptomatic improvement.

CONCLUSIONS

There are clinical variables that could serve as reliable predictors of response to a low-FODMAP, low-sucrose, low-starch diet among patients with IBS. Further research is needed to understand the link between the presence of extra-intestinal symptoms and clinical improvement after dietary interventions for IBS.