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The Effect of Dietary Intervention on Symptoms, Epigenetics, and Gut Microbiota in IBS

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ClinicalTrials.gov Identifier: NCT03306381
Recruitment Status : Completed
First Posted : October 11, 2017
Last Update Posted : December 10, 2019
Information provided by (Responsible Party):
Region Skane

Tracking Information
First Submitted Date  ICMJE September 18, 2017
First Posted Date  ICMJE October 11, 2017
Last Update Posted Date December 10, 2019
Actual Study Start Date  ICMJE January 15, 2018
Actual Primary Completion Date February 28, 2019   (Final data collection date for primary outcome measure)
Current Primary Outcome Measures  ICMJE
 (submitted: October 4, 2017)
Genetic variation of enzymes regulating absorption of disaccharides [ Time Frame: measured at baseline ]
Genetic expression of disaccharide-degradating enzymes will be measured at baseline and related to the response of study participants to dietary intervention.
Original Primary Outcome Measures  ICMJE Same as current
Change History
Current Secondary Outcome Measures  ICMJE
 (submitted: October 4, 2017)
  • Irritable bowel syndrome-subjective severity scores (IBS-SSS) ratings [ Time Frame: 4 weeks ]
    Changes from baseline in subjective symptoms according to the IBS-SSS.
  • Visual analog scale for irritable bowel syndrome (VAS-IBS) ratings [ Time Frame: 4 weeks ]
    Changes from baseline in subjective symptoms according to the VAS-IBS.
  • Gut microbiota composition [ Time Frame: 4 weeks ]
    Changes from baseline in fecal microbiota analysed by 16rs
  • Cytokines [ Time Frame: 4 weeks ]
    Changes from baseline in cytokine plasma concentrations will be assessed by ELISA.
  • microRNA expression [ Time Frame: 4 weeks ]
    Changes from baseline in microRNA expression will be assessed.
Original Secondary Outcome Measures  ICMJE Same as current
Current Other Pre-specified Outcome Measures Not Provided
Original Other Pre-specified Outcome Measures Not Provided
Descriptive Information
Brief Title  ICMJE The Effect of Dietary Intervention on Symptoms, Epigenetics, and Gut Microbiota in IBS
Official Title  ICMJE The Effect of Dietary Intervention on Symptoms in Relation to Genetical Characteristics, Epigenetics, Gut Microbiota, and Autoantibodies in IBS Patients
Brief Summary The aim of the present study is to research whether subjects with irritable bowel syndrome (IBS) display epigenetic/genetic changes or altered microbiota compared to a non-IBS control group. Further, we will investigate if these parameters as well as subjective IBS symptoms are affected by a 4-week long dietary intervention within the IBS patient group.
Detailed Description

The study will be performed on 140 subjects with verified IBS. Patients will be recruited from the clinic of Gastroenterology or Internal medicine as well as primary health care centers. At the start of the study patients will fill out protocols concerning Rom IV criteria (to validate that IBS criteria are filled) as well as IBS symptom rating scales. They will be examined by a physician/researcher who will complete protocols of clinical data. Blood and fecal samples will be collected. A control group of healthy, non-IBS individuals will go through the same procedure as described above.

Study participants with IBS will thereafter be randomized to receive an alternative diet resembling the FODMAP (Fermentable, Oligo-, Di-, Mono-saccharides And Polyols) diet (n=130), or to continue with their regular diet (control group; n=20). After 4 weeks of dietary intervention, there will be a follow-up where blood and fecal samples are once again collected. At this point in time, participants will also fill in IBS symptom rating scales again.

Samples from baseline and 4 weeks will be used for genetic/epigenetic (including genomic-wide association studies), gut microbiota and inflammatory parameter analyses.


To study differences in the above-mentioned parameters between patients and controls as well as before and after dietary intervention, Mann-Whitney U-test and Wilcoxon test will be used, respectively.

Study Type  ICMJE Interventional
Study Phase  ICMJE Not Applicable
Study Design  ICMJE Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: None (Open Label)
Primary Purpose: Basic Science
Condition  ICMJE IBS - Irritable Bowel Syndrome
Intervention  ICMJE Other: Dietary intervention
Elimination of certain products.
Study Arms  ICMJE
  • Experimental: Dietary intervention subject group
    n=130. Participants on low FODMAP-similar diet during 4-week study period.
    Intervention: Other: Dietary intervention
  • No Intervention: Control group
    n=20. Participants on traditional IBS diet during 4-week study period.
Publications * Nilholm C, Manoharan L, Roth B, D'Amato M, Ohlsson B. A starch- and sucrose-reduced dietary intervention in irritable bowel syndrome patients produced a shift in gut microbiota composition along with changes in phylum, genus, and amplicon sequence variant abundances, without affecting the micro-RNA levels. United European Gastroenterol J. 2022 May;10(4):363-375. doi: 10.1002/ueg2.12227. Epub 2022 Apr 28.

*   Includes publications given by the data provider as well as publications identified by ClinicalTrials.gov Identifier (NCT Number) in Medline.
Recruitment Information
Recruitment Status  ICMJE Completed
Actual Enrollment  ICMJE
 (submitted: December 9, 2019)
Original Estimated Enrollment  ICMJE
 (submitted: October 4, 2017)
Actual Study Completion Date  ICMJE February 28, 2019
Actual Primary Completion Date February 28, 2019   (Final data collection date for primary outcome measure)
Eligibility Criteria  ICMJE

Inclusion Criteria:

  • Verified IBS according to Rom IV criteria.

Exclusion Criteria:

  • Serious mental or somatic disease
  • Abuse
  • Inability to understand he Swedish language
  • Already on a diet (e.g. vegan, FODMAP, gluten-free).
Sex/Gender  ICMJE
Sexes Eligible for Study: All
Ages  ICMJE 18 Years and older   (Adult, Older Adult)
Accepts Healthy Volunteers  ICMJE Yes
Contacts  ICMJE Contact information is only displayed when the study is recruiting subjects
Listed Location Countries  ICMJE Sweden
Removed Location Countries  
Administrative Information
NCT Number  ICMJE NCT03306381
Other Study ID Numbers  ICMJE IBS-2017
Has Data Monitoring Committee Not Provided
U.S. FDA-regulated Product
Studies a U.S. FDA-regulated Drug Product: No
Studies a U.S. FDA-regulated Device Product: No
IPD Sharing Statement  ICMJE
Plan to Share IPD: No
Current Responsible Party Region Skane
Original Responsible Party Same as current
Current Study Sponsor  ICMJE Region Skane
Original Study Sponsor  ICMJE Same as current
Collaborators  ICMJE Not Provided
Investigators  ICMJE
Principal Investigator: Bodil Ohlsson, MD, PhD Region Skane
PRS Account Region Skane
Verification Date December 2019

ICMJE     Data element required by the International Committee of Medical Journal Editors and the World Health Organization ICTRP