Low FODMAP Plus PEG 3350 for the Treatment of Patients with Irritable Bowel Syndrome-Constipation

NCT03687814 | Recruiting

• 1 other identifier: HUM00139784
• Study Type: interventional
• Target: 78
• Locations: 1 country
• Sites: 1

Brief Summary

Consecutive patients with Irritable Bowel Syndrome with Constipation (IBS-C) will be recruited from the outpatient clinics of the University of Michigan Health System. Eligible patients will be asked to participate in a study that will test the efficacy the PEG 3350 + a diet low in fermentable oligo, di, monosaccharides, and polyols (FODMAP) vs. PEG 3350 plus sham diet. Blinding dietary advice trials is challenging and therefore the sham diet was based on the criteria set forth by Staudacher et al. which emphasizes that the diet must give the impression that is the true intervention diet with similar restrictions, modifications, and time intensity without impacting the intake of essential nutrients, fiber, and FODMAPs. An example of the sham diet's carbohydrates includes: apples, bananas, and pears, and wheat. Oranges, raspberries, strawberries and rice would not be allowed. Additionally, the physicians analyzing the data will be blinded as to which group the patients were randomized.

Conditions

Irritable Bowel Syndrome Characterized by Constipation

Outcome Measures

Primary Outcomes (1)

• Improvement of abdominal pain as measured by 11-point numerical rating scale

  Compare the proportion of patients with IBS-C on a diet of low FODMAP diet plus PEG 3350 vs. sham diet plus PEG 3350 reporting an improvement of abdominal pain. It is defined 30% reduction in abdominal pain during weeks 3 \& 4 of each diet compared with baseline using an 11-point numerical rating scale (NRS) (0-no pain, 11-intolerable pain). Appropriate between-group statistical comparisons will be conducted.

  during weeks 3 and 4

Secondary Outcomes (11)

• Bloating

  each treatment week (4 weeks)

• abdominal discomfort

  during weeks 3 and 4

• Mean number of SBMs per day

  week 4

• Mean weekly number of spontaneous complete bowel movements

  last treatment week

• Composite endpoint: Full responder was defined as a patient with >3 SBM per week, an increase of ≥1 SBM per week and >30% pain reduction.

  during weeks 3 & 4

Study Arms (2)

Low FODMAP diet plus PEG 3350

EXPERIMENTAL

Subjects will follow a low FODMAP diet and will take PEG 3350 (Miralax).

Other: Low FODMAP diet/PEG 3350

Sham diet plus PEG 3350

SHAM COMPARATOR

Subjects will follow a sham diet and will take PEG 3350 (Miralax).

Other: sham diet/PEG 3350

Interventions

Low FODMAP diet/PEG 3350 OTHER

Subjects will follow a low FODMAP diet and will take PEG 3350 (Miralax) at 17.7 g (single dose) daily for 4 weeks.

Also known as: low FODMAP diet

Low FODMAP diet plus PEG 3350

sham diet/PEG 3350 OTHER

Subjects will follow a sham diet and will take PEG 3350 (Miralax) at 17.7 g (single dose) daily for 4 weeks.

Also known as: sham diet

Sham diet plus PEG 3350

Eligibility Criteria

• Age: 18 Years+
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• \. Subjects aged 18 and older meeting the Rome IV criteria for IBS-C\*:
• Recurrent abdominal pain, on average, at least 1 day/week in the last 3 months, associated with two or more of the following:
• related to defecation
• associated with a change in the frequency of stool (reduction of stools)
• associated with a change in the form of stool (hard or lumpy stools) AND \>25% hard stools and \<25% loose stools \* Criteria fulfilled for the last 3 months

You may not qualify if:

• any other IBS subtype other than IBS-C
• \>3 spontaneous bowel movements during the last 7 days of run-in
• Have cognitive dysfunction or unable to understand or provide written informed consent
• Pregnancy (evaluated by self-report)
• Comorbid medical problems that may affect gastrointestinal transit or motility:
• Inflammatory bowel disease
• Extra-intestinal disease known to affect the gastrointestinal system (i.e., scleroderma, unstable thyroid disease, etc.)
• Severe renal or hepatic disease
• Previous abdominal surgery other than appendectomy, cholecystectomy, and gynecologic/urologic surgery if performed more than six months prior to enrollment
• Previous treatment with the low FODMAP diet under a dietician guidance
• Concurrent medications not permitted including probiotics, antibiotics, prescription or over-the-counter medication for IBS, and narcotics
• New antidepressant use (less than 3 months on stable dose)
• Active participation in another form of dietary therapy

Sponsors & Collaborators

• University of Michigan: lead

Study Sites (1)

University of Michigan

Ann Arbor, Michigan, 48109, United States

RECRUITING

MeSH Terms

Interventions

FODMAP Diet

Intervention Hierarchy (Ancestors)

Elimination Diets; Diet; Nutritional Physiological Phenomena; Diet, Food, and Nutrition; Physiological Phenomena

Study Officials

• Stacy B Menees, MD, MS

  University of Michigan

  PRINCIPAL INVESTIGATOR

Central Study Contacts

Stacy Menees, MD, MS

CONTACT

734-232-3739; sbartnik@med.umich.edu

Amy Liu, BS

CONTACT

734-647-4794; liuyalie@med.umich.edu

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: DOUBLE
• Who Masked: PARTICIPANT, OUTCOMES ASSESSOR
• Purpose: TREATMENT
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Assistant Professor

Study Record Dates

• First Submitted: September 25, 2018
• First Posted: September 27, 2018
• Study Start: November 8, 2018
• Primary Completion: January 1, 2026
• Study Completion: January 1, 2026
• Last Updated: March 4, 2025

Record last verified: 2025-02

Locations

US (1)