Impact of Dietary Fiber Supplementation on Colonic Mucosal Microbiome

Changes in Colonic Microbiome With Fiber Supplementation

This clinical trial tests whether daily fiber supplementation will change the mucosal microbiome of the colon. The microbiome are microorganisms that live in the human gut. They serve a vital role in maintaining health. Certain microbial strains are associated with the growth of colon polyps, which eventually could go on to form colon cancer. Giving dietary fiber supplements may help prevent precancerous polyps from ever developing.

Study Overview

• Status: Recruiting
• Conditions: Benign Colorectal Neoplasm; Non-Neoplastic Anal Disorder
• Intervention / Treatment: Other: Questionnaire Administration; Dietary supplement: Dietary Fiber; Procedure: Proctoscopy or anoscopy with Biopsy; Procedure: Colonoscopy

Detailed Description

PRIMARY OBJECTIVE:

I. To identify how diet, specifically fiber supplementation, alters the microbiome of the colonic mucosa.

OUTLINE:

Patients receive dietary fiber orally (PO) once daily (QD) for 28 days. Patients may undergo standard of care proctoscopy or anoscopy with biopsy on study and at follow-up or may undergo standard of care colonoscopy on study. All patients also undergo collection of blood samples on study and at follow up.

• Study Type: Interventional
• Enrollment (Estimated): 120
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: Shahrose Rahman, M.D.; Phone Number: 503-494-8652; Email: rahmasha@ohsu.edu
• Study Contact Backup: Name: Amber O'Connor; Email: oconnoam@ohsu.edu

Study Locations

• United States
  • Oregon
    • Portland, Oregon, United States, 97239
      • Recruiting
      • OHSU Knight Cancer Institute
      • Contact: Vassiliki L. Tsikitis, M.D.; Phone Number: 503-494-1735; Email: tsikitis@ohsu.edu
      • Principal Investigator: Vassiliki L. Tsikitis, M.D.

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years and older (Adult, Older Adult)
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

• Age >= 18 years
• Ability to understand and the willingness to sign a written informed consent document
• Patients who present with a chief complaint of a benign anorectal pathology including hemorrhoids, anal fissures, and anal fistulas without underlying conditions such as cancer or Crohn's disease or are undergoing a standard of care colonoscopy procedure

Exclusion Criteria:

• Patients with an active malignancy, Crohn's disease, ulcerative colitis, and immunosuppressed patients.
• Patients with hereditary colon cancer syndrome including Lynch syndrome or Familial Adenomatous Polyposis (FAP)
• Patients with a prior history of total or partial colon resection.
• Colorectal pathology such as polyps or cancer

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Supportive Care
• Allocation: N/A
• Interventional Model: Single Group Assignment
• Masking: None (Open Label)

Number of Arms

1

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Supportive care (oral fiber); Patients receive dietary fiber PO QD for 28 days. Patients may undergo standard of care proctoscopy or anoscopy with biopsy on study and at follow up or may undergo standard of care colonoscopy on study. All patients also undergo collection of blood samples on study and at follow up.	Other: Questionnaire Administration; Ancillary studies; Dietary supplement: Dietary Fiber; Given PO; Other Names: Fiber; Procedure: Proctoscopy or anoscopy with Biopsy; Undergo proctoscopy or anoscopy; Procedure: Colonoscopy; Undergo Colonoscopy

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change in microbiome colonic mucosa: taxa abundance	Will use data visualization techniques to understand the data and determine if microbiome count overall (richness) changes occur in patients who are started on fiber supplementation. In order to visualize overall changes after fiber supplementation, will generate plots showing relative abundance of the detected taxa for each subject at baseline and post-supplementation. For each taxa, will generate box plots to visually compare the median and interquartile range (IQR) of abundance between the two time points. Wilcoxon signed rank tests with an alpha level of 0.05 will determine if there is a difference in microbial derived short chain fatty acids after fiber supplementation in the blood and mucosa.	Baseline and post-supplementation, up to 40 days
Change in microbiome colonic mucosa: microbiome diversity	Will use data visualization techniques to understand the data and determine if the types of metabolites (microbiome diversity) cases occur in patients who are started on fiber supplementation. In order to visualize overall changes after fiber supplementation. To assess for changes in microbiome diversity, our primary analysis will compare median Shannon diversity index values at baseline and post-supplementation. The Shannon index estimates diversity using richness and abundance. Will calculate Shannon index values for each participant at each time point and use a Wilcoxon signed rank test with an alpha level of 0.05 to determine if there is a difference in microbiome diversity after fiber supplementation.	Baseline and post-supplementation, up to 40 days

Collaborators and Investigators

• Sponsor: OHSU Knight Cancer Institute
• Investigators: Principal Investigator: Vassiliki L Tsikitis, M.D., OHSU Knight Cancer Institute

Study record dates

Study Major Dates

• Study Start (Actual): April 1, 2023
• Primary Completion (Estimated): December 31, 2024
• Study Completion (Estimated): December 31, 2024

Study Registration Dates

• First Submitted: September 26, 2022
• First Submitted That Met QC Criteria: December 1, 2022
• First Posted (Actual): December 9, 2022

Study Record Updates

• Last Update Posted (Actual): February 20, 2024
• Last Update Submitted That Met QC Criteria: February 16, 2024
• Last Verified: February 1, 2024

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Digestive System Diseases; Neoplasms; Neoplasms by Site; Gastrointestinal Neoplasms; Digestive System Neoplasms; Gastrointestinal Diseases; Colonic Diseases; Intestinal Diseases; Intestinal Neoplasms; Rectal Diseases; Colorectal Neoplasms
• Other Study ID Numbers: STUDY00024054 (Other Identifier: OHSU Knight Cancer Institute); NCI-2022-07495 (Registry Identifier: CTRP (Clinical Trial Reporting Program)); NCI-2022-05415

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No