Systemic Sclerosis DIet for GastrointESTinal Symptoms (DIGEST)

SSc-DIGEST Trial: Systemic Sclerosis DIet for GastrointESTinal Symptoms Randomized Controlled Trial of Low FODMAP, CDED, and NICE Diets for Gastrointestinal Symptoms in Systemic Sclerosis

This research will evaluate the effect of diets on bloating/distention, assess changes in abdominal pain, and overall gastrointestinal symptom burden in Systemic Sclerosis. The researchers will do this by comparing outcomes of people assigned to 3 different diets. Following the research specifics of the diets will be available upon contact with the details listed below.

Study Overview

• Status: Recruiting
• Conditions: Systemic Sclerosis (SSc)
• Intervention / Treatment: Behavioral: Diet 1: Restriction of fermentable carbohydrates; Behavioral: Diet 2: Elimination of foods harmful to gut barrier and microbiome; Behavioral: Diet 3: Regular meal patterns, soluble fiber, and portion control

Detailed Description

The rationale for keeping the diets (arms/interventions names) vague is it prevents other researchers from using these diets in their studies, minimizes expectation bias of patients (who can have preference for one diet over other) and prevents participants from trying other diets before end of study period in case they don't respond.

• Study Type: Interventional
• Enrollment (Estimated): 60
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: Rosemary Gedert; Phone Number: 734-764-6466; Email: ssc-digest@med.umich.edu

Study Locations

• United States
  • Michigan
    • Ann Arbor, Michigan, United States, 48109
      • Recruiting
      • University of Michigan
      • Principal Investigator: Dinesh Khanna, MD, MSc
      • Contact: Rosemary Gedert; Phone Number: 734-764-6466; Email: ssc-digest@med.umich.edu

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

• Diagnosis of systemic sclerosis (SSc) as per ACR/EULAR classification criteria

  .• Self-reported moderate to severe gastrointestinal bloating or distension, with a UCLA SCTC-GIT 2.0 bloating Scale score ≥2.00 on (0.00-3.00 scale) at screening.

• Willingness and ability to comply with dietary intervention and study procedures.
• Ability to provide informed consent.

Exclusion Criteria:

• Diagnosis of inflammatory bowel disease (Crohn's disease or ulcerative colitis) or celiac disease.
• Use of systemic antibiotics within 4 weeks prior to baseline.
• History of gastrointestinal surgery (other than cholecystectomy or appendectomy unless in the last 3 months).
• Severe cognitive impairment or psychiatric illness that would limit ability to follow dietary instructions.
• Known allergy or intolerance to major components of any of the study diets (e.g., lactose, gluten) unless manageable within diet framework.
• Current or recent (within 3 months) dietary intervention for managing GI symptoms (e.g. gluten-free diet, low FODMAP diet, etc.).
• Clinically significant self-reported (≥10 percent weight loss) in the last 3 months
• BMI less than 20
• Ongoing tube feeds or TPN
• Participating in another interventional trial
• Pregnancy or lactation, or planning pregnancy in the next 6 months

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Double

Number of Arms

3

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Diet 1: Restriction of fermentable carbohydrates	Behavioral: Diet 1: Restriction of fermentable carbohydrates; 6 weeks guided diet under the supervision of a dietician restricting fermentable carbohydrates known to trigger GI symptoms.
Experimental: Diet 2: Elimination of foods harmful to gut barrier and microbiome	Behavioral: Diet 2: Elimination of foods harmful to gut barrier and microbiome; 6 weeks guided diet under the supervision of a dietician eliminating of foods harmful to gut barrier and microbiome
Experimental: Diet 3: Regular meal patterns, soluble fiber, and portion control	Behavioral: Diet 3: Regular meal patterns, soluble fiber, and portion control; 6 weeks guided diet under the supervision of a dietician emphasizing regular meal patterns, soluble fiber, and portion control.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change in Bloating severity	As assessed by the Patient-Reported Outcomes Measurement Information System (PROMIS) Scale v1.1 - Gastrointestinal Gas and Bloating 13a - 13 questions with raw summed scores ranging from 13-36.	Baseline to week 6

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change in Bloating severity	As assessed by the UCLA Scleroderma Clinical Trial Consortium Gastrointestinal Tract (UCLA SCTC GIT 2.0). The bloating score is a subsection of 4 questions with 4 options each. The score ranges from .0-3 where higher numbers indicate more frequent bloating.	Baseline to week 6
Change in Abdominal pain severity	As assessed by the PROMIS Scale v1.0 - Gastrointestinal Belly Pain 5a - 5 questions with raw summed score range of 6-25.	Baseline to week 6
Change in Overall GI symptom	UCLA SCTC GIT 2.0 total score (all sections but constipation) with a range of (0-2.83). Higher scores indicate more severe symtoms.	Baseline to week 6

Collaborators and Investigators

• Sponsor: University of Michigan
• Investigators: Principal Investigator: Dinesh Khanna, MD, MSc, University of Michigan

Study record dates

Study Major Dates

• Study Start (Estimated): March 16, 2026
• Primary Completion (Estimated): April 1, 2027
• Study Completion (Estimated): April 1, 2027

Study Registration Dates

• First Submitted: January 21, 2026
• First Submitted That Met QC Criteria: February 6, 2026
• First Posted (Actual): February 11, 2026

Study Record Updates

• Last Update Posted (Actual): March 24, 2026
• Last Update Submitted That Met QC Criteria: March 20, 2026
• Last Verified: March 1, 2026

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Connective Tissue Diseases; Skin Diseases; Skin and Connective Tissue Diseases; Scleroderma, Systemic; Environment and Public Health; Microbiological Phenomena; Biota; Biodiversity; Ecosystem; Environment; Ecological and Environmental Phenomena; Biological Phenomena; Microbiota
• Other Study ID Numbers: HUM00285136

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

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