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Completed

NCT Number: NCT05182593

The Effects of FODMAPs in Patients With Irritable Bowel Syndrome

Patients with Irritable Bowel Syndrome (IBS) often link their symptoms to foods. Interest in dietary management recently increased, including the use of a low FODMAP diet.

To investigate relation of FODMAPs and IBS, a randomized, double-blind, cross-over trial will be carried out in adult (>18) patients with IBS according to Rome IV criteria. The aim is to assess low FODMAP diet versus moderate/high FODMAP diet in IBS patients.

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Key information

Conditions

Irritable Bowel Syndrome Colonic Diseases Colonic Diseases, Functional Digestive System Diseases Gastrointestinal Diseases Intestinal Diseases

Age range

18 year–75 year

Sex eligibility

All sexes

Study type

Interventional

Phase

Not applicable

Primary location

Magnus Simren

Gothenburg, Non-US/Non-Canadian, 44331, Sweden

About this study

The study is a randomized, double-blind, cross-over trial.

The aim is to assess the effects of low fermentable oligosaccharides, disaccharides, monosaccharides and polyols (FODMAP) diet compared to moderate/high FODMAP diet in IBS patients on gastrointestinal symptoms and psychological factors. The primary hypothesis is that the low FODMAP diet decreases gastrointestinal symptoms compared to moderate/high FODMAP diet, and that this change is accompanied with reduced psychological distress.

IBS patients (Rome IV) are challenged with FODMAPs in this randomized, double-blinded, cross-over study. The subjects will start with the low FODMAP diet or moderate/high FODMAP diet and cross over to the other intervention (both for 7 days). In between the interventions, there is a wash-out period of at least 14 days. The subjects will receive ready-made meals from the hospital kitchen (lunch and dinner) and in between snacks. The subjects are instructed to buy breakfast themselves and the subjects will receive information on which other foods to avoid, without mentioning 'FODMAPs'. The subjects will follow their usual diet (as before initiation of the study) during the wash-out period.

Primary outcomes are change in gastrointestinal symptoms, assessed by questionnaires, including IBS Severity Scoring System (IBS-SSS) (7-10 day recall and modified daily) and Gastrointestinal Symptom Rating Scale -IBS (GSRS-IBS). A 50-point reduction in IBS-SSS indicates clinical response. Bacterial fermentation (exhaled hydrogen and methane) and visceral sensitivity will be measured using the Lactulose Nutrient Challenge Test. Secondary outcomes are change in psychological factors and assessed by questionnaires, including Central Sensitization Index (CSI), Hospital Anxiety and Depression Scale (HADS), Patient Health Questionnaire (PHQ)-15 and Visceral Sensitivity Index (VSI).

Who can participate

Healthy volunteers accepted: No

Only the study team can determine whether someone qualifies for participation.

Inclusion criteria

  • Adult patients with IBS according to Rome IV criteria

Exclusion criteria

  • allergy or documented intolerance to food
  • severe cardiovascular disease
  • severe hepatic disease
  • severe neurological disease
  • severe psychiatric disease
  • celiac disease
  • inflammatory bowel diseases
  • diabetes
  • bowel dysfunction related to previous surgery
  • pregnant or lactating women
  • use of antibiotics within four weeks before inclusion
  • strict avoidance of foods

Treatment and study plan

Diet moderate/high in FODMAPs

Other

The subjects will obtain meal boxes prepared in the hospital kitchen with a moderately high FODMAP content (23 grams/day)

Diet low in FODMAPs

Other

The subjects will obtain meal boxes prepared in the hospital kitchen with a low FODMAP content (<5 grams/day)

Primary outcomes

  1. Change in Irritable Bowel Syndrome-Severity Scoring System (IBS-SSS) (7-10 days recall questionnaire)

    Time frame: Baseline (day 0), day 7, day 21, day 28

    Irritable Bowel Syndrome-Severity Scoring System (IBS-SSS) is a validated questionnaire that incorporates typical IBS symptoms such as abdominal pain, abdominal distension and bowel dysfunction, as well as quality of life. Subjects rated their symptoms on a visual analogue scale. The maximum achievable score is 500 points (sum of the 5 scales). A reduction in the total IBS-SSS score of at least 50 points is considered to indicate a clinically significant improvement in symptoms. The scale can also be used to classify IBS symptoms severity: <75 points (no symptoms), 75-175 points (mild symptoms), 175-300 points (moderate symptoms) and >300 points (severe symptoms). Measured after both dietary periods and at baseline of both periods.

  2. Change in Irritable Bowel Syndrome-Severity Scoring System (IBS-SSS) (modified, daily IBS-SSS)

    Time frame: Daily during day 7 to 14, and day 21 to 28

    Irritable Bowel Syndrome-Severity Scoring System (IBS-SSS) is a validated questionnaire that incorporates typical IBS symptoms such as abdominal pain, abdominal distension and bowel dysfunction, as well as quality of life. Subjects rated their symptoms on a visual analogue scale. The maximum achievable score is 500 points (sum of the 5 scales). A reduction in the total IBS-SSS score of at least 50 points is considered to indicate a clinically significant improvement in symptoms. The scale can also be used to classify IBS symptoms severity: <75 points (no symptoms), 75-175 points (mild symptoms), 175-300 points (moderate symptoms) and >300 points (severe symptoms). Measured after both dietary periods and at baseline of both periods.

  3. Change in Gastrointestinal Symptom Rating Scale - Irritable Bowel Syndrome (GSRS-IBS)

    Time frame: Baseline (day 0), day 7, day 21, day 28

    Change in Gastrointestinal Symptom Rating Scale - Irritable Bowel Syndrome (GSRS-IBS) measures symptom severity and symptom frequency in IBS patients and is a reliable and validated questionnaire. Thirteen questions are evaluated and rated from 1 (no discomfort at all) to 7 (very severe discomfort) on a Likert scale. The total scores can range from 13 to 91 (sum of the domains). The GSRS-IBS evaluates 5 domains: abdominal pain, bloating, constipation, diarrhea and satiety. Measured after both dietary periods and at baseline of both periods.

Secondary outcomes

  1. Change in stool consistency and frequency, measured by Bristol Stool Form (BSF)

    Time frame: Baseline (day 0), day 7, day 21, day 28

    Change in Bristol Stool Form, stool consistency/frequency per day after both dietary periods

  2. Change in Hospital Anxiety and Depression Scale (HADS) score

    Time frame: Baseline (day 0), day 7, day 21, day 28

    The Hospital Anxiety and Depression Scale (HADS) contains 7 items for depression and 7 for anxiety. Each item is scored from 0 to 3, and therefore the total score per sub-scale can range from 0 to 21. When subjects score >10 on 1 or 2 of the sub-scales, clinically significant psychological distress (anxiety or depression) is likely present. Measured after both dietary periods and at baseline of both periods.

  3. Change in Patient health questionnaire-15 (PHQ-15)

    Time frame: Baseline (day 0), day 7, day 21, day 28

    The (PHQ-15) is a validated questionnaire that evaluates 15 somatic symptoms and can be used as a screening tool for somatization in clinical research. The maximum score for men is 28 and 30 for women due to a question about menstrual problems. Measured after both dietary periods and at baseline of both periods.

  4. Change in Visceral Sensitivity Index (VSI)

    Time frame: Baseline (day 0), day 7, day 21, day 28

    The Visceral Sensitivity Index (VSI) is a validated and reliable psychometric instrument which assesses gastrointestinal symptom-specific anxiety. The VSI contains 15 items that are scored from 0 to 5, therefore the total score can range from 0 to 75. Higher scores indicate more severe gastrointestinal symptom-specific anxiety. Measured after both dietary periods and at baseline of both periods.

Other outcomes

  1. Visceral Sensitivity and Bacterial Fermentation

    Time frame: Baseline (day 0)

    Visceral Sensitivity and Bacterial Fermentation measured by the Lactulose Nutrient Challenge Test. To assess if visceral sensitivity and/or bacterial fermentation are predictors of clinical response to the low FODMAP diet or clinical worsening to the moderate/high FODMAP diet.

  2. Change in microbiota content of frozen fecal samples

    Time frame: Baseline (day 0), day 7, day 21, day 28

    Fecal microbiota analysis using 16 S RNA technique and Dysbiosis Test. Analyses will be done on samples from before and after both dietary periods.

  3. Change in metabolites content

    Time frame: Baseline (day 0), day 7, day 21, day 28

    Frozen urine/serum/fecal samples will be analyzed in the future by gas/liquid chromatography mass spectrometry (metabolomics) analysis.Analyses will be done on samples from before and after both dietary periods.

Sponsors and collaborators

Lead sponsor

Sahlgrenska University Hospital

Other

Registry information

Official study title

The Effects of Fermentable Oligosaccharides, Disaccharides, Monosaccharides and Polyols (FODMAPs) in Patients With Irritable Bowel Syndrome

Acronym: Sens-IBS

Important dates

Study start
2019
Primary completion
2020
Study completion
2020
First posted
Jan 10, 2022
Registry last updated
Jan 26, 2022

OpenTrials presents study information sourced from ClinicalTrials.gov. The official registry record should be consulted for the latest information.

View the official ClinicalTrials.gov record (opens in a new tab)

This listing is for discovery and informational purposes only. It is not medical advice, does not guarantee that a study is recruiting, and does not determine eligibility. Contact the study team and a qualified healthcare professional when considering participation.

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