Mediterranean Diet Intervention to Improve Gastrointestinal Function in Parkinson's Disease a Randomized, Controlled, Clinical Trial

Not Applicable

Completed

• Conditions: Parkinson Disease
• Interventions: Other: Standard of care + Mediterranean diet (intervention); Other: Standard of care (control)

• Registration Number: NCT04683900
• Lead Sponsor: University of Florida

Brief Summary

This is a 10-week randomized, controlled study to investigate the effect of a Mediterranean diet intervention on gastrointestinal function in Parkinson's disease. After a 2-week run-in period, participants will be instructed to receive standard of care for constipation or receive standard of care + follow a Mediterranean diet for 8 weeks and answer daily and weekly questionnaires. Nutritional and neurological evaluations and stool samples will be collected at 0, 4 and 8 weeks.

Detailed Description

Not available

Study Timeline

• Study First Submitted: 2020-12-17
• Study First Submitted QC: 2020-12-23
• Study First Posted: 2020-12-24
• Study Start: 2021-02-08
• Primary Completion: 2022-06-07
• Study Completion: 2022-06-07
• Status Verified: 2022-07
• Last Update Submitted: 2022-07-11
• Last Update Posted: 2022-07-12

Recruitment & Eligibility

• Status: COMPLETED
• Sex: All
• Target Recruitment: 46

Inclusion Criteria

• Physician-diagnosed Parkinson's disease aged 40-85 years
• Drug naïve or on stable dosage of Parkinson's medications with no plans to change for the duration of the study protocol
• Hoehn & Yahr stage =<2.5 in the clinical "ON" state
• Constipation syndrome scores >=2.0 based on the GSRS
• Consume <20 grams of fiber daily based on the Block Fruit/Vegetable/Fiber screener
• Able to complete informed consent in English
• Willing to maintain habitual diet through the pre-baseline period.
• Willing to make dietary changes to follow a Mediterranean diet and/or receive standard of care for constipation during the intervention period.
• Willing to complete daily and weekly questionnaires and 12 dietary recalls over approximately 10 weeks.
• Able to provide stool samples during the study collection periods.
• Willing to avoid strenuous exercise and alcohol such as beer, wine, and cocktails 24 hours prior to each of the 3 study visits.
• Able to fast (no food or drink, except water, or decaf tea) at least 12 hours before each study visit
• Willing to discontinue taking prebiotic, herbal, or high-dose vitamin or mineral supplements that may impact inflammation during the pre-baseline period and throughout the study protocol.

Exclusion Criteria

• Atypical or secondary Parkinsonism
• Underweight (BMI <18.5)
• History of deep brain stimulation (DBS) surgery
• Regular use of enemas or suppositories to alleviate constipation (e.g., >1 time per week)
• Use of another investigational product within 3 months of the screening visit
• Antibiotic or probiotic supplement use within 2 months from the day of stool collection
• Currently being treated for a physician-diagnosed GI disease or condition other than constipation, irritable bowel disease, gastroparesis, reflux or diverticular disease

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: PARALLEL

Arm && Interventions

Group	Intervention	Description
Standard of Care + Mediterranean Diet	Standard of care + Mediterranean diet (intervention)	Participants will be given standard of care for constipation (handout) plus individualized diet education on the Mediterranean diet and instructed to follow the diet during the 8-week intervention period. Diet education will be administered by a study dietitian and followed with weekly phone calls to ensure compliance, improve adherence to the diet and monitor for adverse events.
Standard of Care	Standard of care (control)	Participants will be given standard of care for constipation (handout) to utilize during the 8-week intervention period. A study dietitian will follow up with weekly phone calls to support adherence and monitor for adverse events.

Primary Outcome Measures

Name	Time	Method
GSRS Constipation Syndrome Score	10 weeks	The difference between mean change (final - baseline) in constipation syndrome scores for the Med diet versus control diet.

Secondary Outcome Measures

Name	Time	Method
Quality of Life Related to Digestive Health	Every week up to 10 weeks	Weekly GI experiences assessed using an in-house Digestion-Associated Quality of Life questionnaire.
Digestive Health	Every week up to 10 weeks	Weekly GI symptoms assessed using the Gastrointestinal Symptom Rating Scale (GSRS). The GSRS consists of 15 questions related to 5 syndromes, constipation, diarrhea, reflux, abdominal pain, and indigestion. Symptoms are scored 1=no discomfort to 7=very severe discomfort. Scores from each of the 15 questions are summed for the total GSRS score.
Fecal Microbial Diversity	Baseline (Week 0); Midpoint (Week 4); Final (Week 8)	Changes in fecal microbial composition and diversity (i.e. alpha and beta diversity) will be assessed.
Laxative Usage	Each week up to 10 weeks	Compare number of days using laxative medications between the intervention and control groups.
Fecal Microbial Quantitative Polymerase Chain Reaction (qPCR)	Baseline (Week 0); Midpoint (Week 4); Final (Week 8)	Changes in fecal microbial composition to quantify bacterial species of interest (e.g., F. prausnitzii, Prevotella, Roseburia, Bilophila, Akkermansia, etc.) will be assessed.
Stool Frequency	Each week up to 10 weeks	Compare the number of stools between the intervention and control groups
Stool Form	Each day up to 10 weeks	Compare stool form, as measured by the Bristol Stool Form Scale (BSFS), between the intervention and control groups. The BSFS is scored between 1 (hard stool) - 7 (liquid stool).
Intestinal Inflammation and Permeability	Baseline (Week 0); Midpoint (Week 4); Final (Week 8)	Changes in fecal calprotectin and zonulin will be assessed using enzyme-linked immunosorbent assay

Trial Locations

Locations (1)

University of Florida; 🇺🇸 Gainesville, Florida, United States