Clinical trial NCT03306381: The Effect of Dietary Intervention on Symptoms, Epigenetics, and Gut Microbiota in IBS
Official title: The Effect of Dietary Intervention on Symptoms in Relation to Genetical Characteristics, Epigenetics, Gut Microbiota, and Autoantibodies in IBS Patients
Study type: INTERVENTIONAL
Overall status: COMPLETED
Phase: NA
Conditions: IBS - Irritable Bowel Syndrome
Keywords: IBS
Epigenetics
Dietary intervention
Gut Microbiota
Inflammation
Genetics
Lead sponsor: Region Skane
Sponsor class: OTHER
First posted: 2017-10-11
Enrollment: 105
Sex: ALL
Minimum age (years): 18
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: yes
Allocation: RANDOMIZED
Intervention model: PARALLEL
Primary purpose: BASIC_SCIENCE

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.

Statistics

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.

Eligibility criteria: 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).

Primary outcomes:
measure: Genetic variation of enzymes regulating absorption of disaccharides
timeFrame: measured at baseline
Secondary outcomes:
measure: Irritable bowel syndrome-subjective severity scores (IBS-SSS) ratings
timeFrame: 4 weeks
measure: Visual analog scale for irritable bowel syndrome (VAS-IBS) ratings
timeFrame: 4 weeks
measure: Gut microbiota composition
timeFrame: 4 weeks
measure: Cytokines
timeFrame: 4 weeks
measure: microRNA expression
timeFrame: 4 weeks
Other outcomes:
Locations:
city: Malmö
country: Sweden
facility: Deartment of INternal Medicine
Study officials:
affiliation: Region Skane
name: Bodil Ohlsson, MD, PhD
role: PRINCIPAL_INVESTIGATOR
References:
citation: 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.