Effectiveness of a high fiber diet in improving constipation in patients with defecatory dyssynergy under treatment with anorrectal biofeedback. Exploratory, randomized clinical trial. / Eficacia de la dieta alta en fibra en la mejora del estreñimiento en pacientes con disinergia defecatoria en tratamiento con biofeedback anorrectal. Ensayo clínico exploratorio, aleatorizado.

INTRODUCTION: Fiber is the initial treatment in chronic functional constipation. However, its role in the group of patients with defecatory dyssynergy is not well established. The objective of the study is to evaluate the efficacy and safety of a high fiber diet in patients with defecatory dyssynergy in the treatment with anorectal biofeedback. PATIENTS AND METHODS: An exploratory, randomized (1:1), double-blind, controlled «add-on¼ clinical trial was carried out in a reference center in Spain in patients with functional constipation and defecatory dyssynergy according to the ROMEIV criteria. CONTROL GROUP: treatment with biofeedback and low-fiber diet (15-20g/day). Experimental group: treatment with biofeedback and high fiber diet (25-30g/day). Analyzed: responder (primary endpoint), patient whose defecatory dyssynergy had been corrected (>20% reduction in anal pressure during the defecation maneuver and normal balloon expulsion test); anorectal parameters (anal relaxation, reduced straining); safety (abdominal symptoms: flatulence, pain, borborygmus, bloating). RESULTS: A total of 44 patients were randomized: 22 per group. The percentage of responders was 75% (15/20; 95%CI: 53 89%) control group and 70% (14/20; 95%CI: 48-85%) experimental group, P=.225. Differences in favor of the control group were only observed in abdominal symptoms: flatulence (P=.028), abdominal distension (P=.041) and digestive comfort (P=.043). CONCLUSIONS: In patients with defecatory dyssynergy, a high-fiber diet not only does not improve the efficacy of anorectal biofeedback but is associated with a loss of improvement in abdominal symptoms.

Effects of Prebiotics vs a Diet Low in FODMAPs in Patients With Functional Gut Disorders.

Prebiotics and diets low in fermentable oligo-, di-, mono-saccharides and polyols (low-FODMAP diet) might reduce symptoms in patients with functional gastrointestinal disorders, despite reports that some nonabsorbable, fermentable meal products (prebiotics) provide substrates for colonic bacteria and thereby increase gas production. We performed a randomized, parallel, double-blind study of patients with functional gastrointestinal disorders with flatulence. We compared the effects of a prebiotic supplement (2.8 g/d Bimuno containing 1.37 g beta-galactooligosaccharide) plus a placebo (Mediterranean-type diet (prebiotic group, n = 19) vs a placebo supplement (2.8 g xylose) plus a diet low in FODMAP (low-FODMAP group, n = 21) for 4 weeks; patients were then followed for 2 weeks. The primary outcome was effects on composition of the fecal microbiota, analyzed by 16S sequencing. Secondary outcomes were intestinal gas production and digestive sensations. After 4 weeks, we observed opposite effects on microbiota in each group, particularly in relation to the abundance of Bifidobacterium sequences (increase in the prebiotic group and decrease in the low-FODMAP group; P = .042), and Bilophila wadsworthia (decrease in the prebiotic group and increase in the low-FODMAP group; P = .050). After 4 weeks, both groups had statistically significant reductions in all symptom scores, except reductions in flatulence and borborygmi were not significant in the prebiotic group. Although the decrease in symptoms persisted for 2 weeks after patients discontinued prebiotic supplementation, symptoms reappeared immediately after patients discontinued the low-FODMAP diet. Intermittent prebiotic administration might therefore be an alternative to dietary restrictions for patients with functional gut symptoms. ClinicalTrials.gov no.: NCT02210572.

[The diet low in fermentable carbohydrates short chain and polyols improves symptoms in patients with functional gastrointestinal disorders in Spain]. / La dieta con bajo contenido en hidratos de carbono de cadena corta y polioles fermentables mejora los síntomas en pacientes con trastornos funcionales gastrointestinales en España.

BACKGROUND AND AIMS: Successful treatment of patients with irritable bowel syndrome (IBS) often remains elusive. Recent studies in Australia, the United Kingdom and New Zealand have suggested the efficacy of a diet low in fermentable oligosaccharides, disaccharides, monosaccharides and polyols (FODMAPs) in the management of these patients. The aims of this study were to determine whether a diet low in FODMAPs improves symptoms in patients with functional gastrointestinal disorders (FGID) in Spain and to analyze the predictors of a good response. PATIENTS AND METHODS: A prospective study was carried out in consecutive patients with FGID type IBS and functioanl abdominal bloating. At inclusion all patients underwent an assessment through a baseline demographic questionnaire of symptoms of anxiety and depression and quality of life. A hydrogen breath test with lactose and fructose was performed and a low FODMAPs diet was indicated for 2 months by expert dietitians. These tests were taken as a reference. A positive response was defined as an improvement of at least 5 points out of a possible 10 in the symptom questionnaire. RESULTS: We included 30 patients (24 women, 39 [12] years). The response to the low FODMAPs diet was positive in controlling overall symptoms and specific symptoms such as functioanl abdominal bloating, abdominal pain, diarrhea, flatulence, nausea and fatigue in more than 70% of patients (P<.05). By contrast, constipation was controlled in only 48% of patients (P>.05). Adherence to the diet was good in 87% of patients and was a predictor of positive response in the univariate analysis. CONCLUSIONS: A diet low in FODMAPs is associated with symptom improvement in patients with IBS and functioanl abdominal bloating. Adherence to the diet was a determining factor.