Comparing Two Types of Diets on Psychological and Gastrointestinal Symptoms

A Randomized Trial Comparing Two Types of Diets on Psychological and Gastrointestinal Symptoms

This pilot study proposes to gain a better understanding of the health benefits of the popular "paleo-diet" in patients with irritable bowel syndrome (IBS) and explore underlying mechanisms of benefit.

Study Overview

• Status: Completed
• Conditions: Irritable Bowel Syndrome
• Intervention / Treatment: Other: Paleolithic diet; Other: General Healthful Diet

Detailed Description

In the proposed study, the primary hypothesis is that, compared with a customary diet, consumption of a paleo-diet will improve psychological and gastrointestinal symptoms in patients with irritable bowel syndrome. Investigators also hypothesize consumption of the Paleolithic diet will result in decreased intestinal permeability, decreased inflammatory markers, and changes in the gut microbiome and microbiologic profiles.

• Study Type: Interventional
• Enrollment (Actual): 40
• Phase: Not Applicable

Contacts and Locations

Study Locations

• United States
  • Maryland
    • Baltimore, Maryland, United States, 21287
      • Johns Hopkins University

Participation Criteria

Eligibility Criteria

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

Description

Inclusion Criteria:

• Patients with mild to moderate Irritable Bowel Syndrome (IBS) and mild to moderate anxiety or depression
• Other causes of bowel symptoms excluded to the satisfaction of the Study Team
• Age at least 18 years at initial screening visit
• Patients who are able to sign and understand the study's informed consent form
• Patients able to complete all screening evaluations and procedures

Exclusion Criteria:

• Patients in inpatient hospital care
• Severe or refractory bowel or psychological symptoms
• Current consumption of a Paleolithic diet
• Known Celiac disease
• Uncontrolled thyroid disease as indicated by an abnormal thyroid stimulating hormone (TSH) level
• Uncontrolled diabetes as indicated by a HbA1c equal to 6.5 or greater
• Patients unable to speak English
• Inability to obtain informed consent
• Pregnant or nursing women
• Any condition, which in the opinion of the investigator, would interfere with study requirements

Study Plan

How is the study designed?

Design Details

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

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Paleolithic Diet	Other: Paleolithic diet; Paleolithic diet
Active Comparator: General Healthful Diet	Other: General Healthful Diet; General Healthful Diet

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Vitality	Vitality as measured on the vitality subscale of the short form health survey (SF36). This instrument assesses vitality (energy level and fatigue) and is a subscale of SF36, a general health survey designed for use in clinical practice and research, health policy evaluation and general population surveys. The Vitality Subscale score is determined by responses to 4 items: Did you feel full of life? Did you have a lot of energy? Did you feel worn out? Did you feel tired? The lower the score the more disability. The higher the score the less disability.	The change between baseline and 4 weeks (post-intervention).

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Anxiety	Anxiety as measured by the Generalized Anxiety Disorder 7-item (GAD-7) questionnaire. GAD-7 Questionnaire: This is a 7 item inventory rated on a 4 point Likert-type scale. Its purpose is to allow for brief and accurate detection of anxiety as well as for longitudinal anxiety symptom evaluation. Lower scores indicate less severe symptoms and higher scores equal more severe symptoms.	The change between baseline and 4 weeks (post-intervention).
Depression	Depression as measured by the Patient Health Questionnaire-9' (PHQ-9) questionnaire. PHQ-9: This is a 9 item inventory rated on a 4 point Likert-type scale. Its purpose is to allow for brief and accurate diagnosis of depression as well as for longitudinal depression symptom evaluation. Lower scores indicate less severe symptoms and higher scores equal more severe symptoms.	The change between baseline and 4 weeks (post-intervention).
Activity level	Activity level/amount of exercise as measured by the Godin Leisure-Time Exercise Questionnaire. The Godin Leisure-Time Exercise Questionnaire is a simple questionnaire to measure a person's leisure time exercise. It is designed to be reliable valid and easy to complete quickly without a need for detailed review. Lower scores indicate less activity and higher scores equal more activity.	The change between baseline and 4 weeks (post-intervention).
Gastrointestinal symptoms	Gastrointestinal symptoms as measured by the NIH-Promis Gastrointestinal Symptom Scale a. NIH-Promis Gastrointestinal Symptom Scales for 8 domains: Gastroesophageal reflux (13 items), disrupted swallowing (7 items), diarrhea (5 items), bowel incontinence/soilage (4 items), nausea and vomiting (4 items), constipation (9 items), belly pain (6 items), and gas/bloat/flatulence (12 items). Lower scores indicate less severe symptoms and higher scores equal more severe symptoms.	The change between baseline and 4 weeks (post-intervention).
Visceral sensitivity	Visceral sensitivity as measured by the Visceral Sensitivity Index. Visceral Sensitivity Index assesses gastrointestinal-specific anxiety, the cognitive, affective, and behavioral response to fear of gastrointestinal sensations, symptoms, and the context in which these visceral sensations and symptoms occur. Lower scores indicate less severe symptoms and higher scores equal more severe symptoms.	The change between baseline and 4 weeks (post-intervention).
Overall health status (Short Health Scale)	Overall health status as measured by the Short Health Scale questionnaires. The "Short Health Scale" is a 4-item questionnaire covering aspects of subjective health. Lower scores indicate less severe symptoms and higher scores equal more severe symptoms.	The change between baseline and 4 weeks (post-intervention).
Overall health status (EQ-5D)	Overall health status (global health outcomes measure) as measured by the EuroQol 5 Dimension (EQ-5D) The EQ-5D descriptive system consists of five dimensions: Mobility, Self-care, Usual activities, Pain/discomfort, Anxiety/depression. Scores range from 5-25, with higher scores indicating more severe symptoms/decreased quality of life.descriptive system consists of five dimensions: Mobility, Self-care, Usual activities, Pain/discomfort, Anxiety/depression. Lower scores indicate less severe symptoms and higher scores equal more severe symptoms.	The change between baseline and 4 weeks (post-intervention).

Other Outcome Measures

Outcome Measure	Measure Description	Time Frame
Intestinal permeability	Change in intestinal permeability as measured by plasma zonulin levels	The change between baseline and 4 weeks (post-intervention).
Change in inflammatory markers	Change in inflammatory markers as measured by serum C-reactive protein levels	The change between baseline and 4 weeks (post-intervention).
Change in stool metabolomics	Change in stool metabolomics as measured by stool metabolite testing.	The change between baseline and 4 weeks (post-intervention).
Change in stool microbiome profile	Change in stool microbiota profile as measured by 16S DNA sequencing of stool samples.	The change between baseline and 4 weeks (post-intervention).
Biobank specimen collection of urine.	Biobank specimen collection of stool, blood, urine, and saliva to be studied in future studies	The change between baseline and 4 weeks (post-intervention).
Biobank specimen collection of stool.	Biobank specimen collection of stool, blood, urine, and saliva to be studied in future studies	The change between baseline and 4 weeks (post-intervention).
Biobank specimen collection of saliva.	Biobank specimen collection of stool, blood, urine, and saliva to be studied in future studies	The change between baseline and 4 weeks (post-intervention).
Biobank specimen collection of blood.	Biobank specimen collection of stool, blood, urine, and saliva to be studied in future studies	The change between baseline and 4 weeks (post-intervention).

Collaborators and Investigators

• Sponsor: Johns Hopkins University

Study record dates

Study Major Dates

• Study Start (Actual): April 24, 2018
• Primary Completion (Actual): April 1, 2020
• Study Completion (Actual): April 1, 2020

Study Registration Dates

• First Submitted: January 18, 2017
• First Submitted That Met QC Criteria: January 25, 2017
• First Posted (Estimate): January 30, 2017

Study Record Updates

• Last Update Posted (Actual): May 7, 2020
• Last Update Submitted That Met QC Criteria: May 5, 2020
• Last Verified: May 1, 2020

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Digestive System Diseases; Gastrointestinal Diseases; Colonic Diseases, Functional; Colonic Diseases; Intestinal Diseases; Irritable Bowel Syndrome
• Other Study ID Numbers: IRB00082222

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: UNDECIDED

Drug and device information, study documents

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