Nutritional Intervention for Constipation Symptoms in Patients With Parkinson's Disease

Not Applicable

Not yet recruiting

• Conditions: Parkinsons Disease (PD); Constipation - Functional

• Registration Number: NCT07213856
• Lead Sponsor: Hospital de Clinicas de Porto Alegre

Brief Summary

The goal of this clinical trial is to evaluate whether a dietitian-guided nutritional intervention can improve constipation symptoms in people with Parkinson's disease (PD). The main questions it aims to answer are:

* Can a dietitian-guided nutritional intervention increase the number of weekly bowel movements in individuals with PD and functional constipation?

* Can this intervention positively influence gut microbiota composition, dietary intake, and nutritional status?

Researchers will compare the intervention group to a control group that will receive general dietary guidance only after the study period, to see if the intervention leads to improvements in bowel function and related health outcomes.

Participants will:

* Follow a diet plan developed by a dietitian, based on dietary reference intakes and tailored to the needs of individuals with PD and constipation

* Participate in follow-up sessions with the dietitian for 3 months

* Complete assessments at baseline, midpoint, and end of the intervention to evaluate bowel function, constipation symptoms, gut microbiota, nutritional status, and diet quality

Detailed Description

Not available

Study Timeline

• Status Verified: 2025-10
• Study Start: 2025-10-01
• Study First Submitted: 2025-10-02
• Study First Submitted QC: 2025-10-02
• Last Update Submitted: 2025-10-02
• Study First Posted: 2025-10-09
• Last Update Posted: 2025-10-09
• Primary Completion: 2027-06
• Study Completion: 2029-08-01

Recruitment & Eligibility

• Status: NOT_YET_RECRUITING
• Sex: All
• Target Recruitment: 54

Inclusion Criteria

• Adults with a previous diagnosis of Parkinson's disease
• On a stable dose of levodopa for at least 3 months
• Diagnosis of Functional Constipation by the Rome IV protocol

Exclusion Criteria

• Diagnosis of atypical or secondary parkinsonism
• Hoehn and Yahr stage greater than 2
• Presence of severe neurological or psychiatric disorders that impair the ability to participate in study procedures
• Previous diagnosis of dementia
• Presence of comorbidities such as active cancer, chronic obstructive pulmonary disease (COPD), heart failure, and/or chronic kidney disease
• History of gastrointestinal cancers, inflammatory bowel diseases, or surgeries involving the gastrointestinal tract
• Constipation secondary to clinical conditions such as hypothyroidism or diabetes mellitus
• Use of opioids
• Use of probiotics or antibiotics in the past 8 weeks
• Continuous use of laxatives in the past 8 weeks
• Presence of severe dysphagia according to the Functional Oral Intake Scale (FOIS)
• Individuals receiving enteral or parenteral nutrition
• Individuals under nutritional follow-up in the past 3 months

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: PARALLEL

Primary Outcome Measures

Name	Time	Method
Change in weekly bowel movement frequency	Baseline and 90 days	Mean change in the number of spontaneous bowel movements per week from baseline to 12 weeks, based on participant-reported bowel diaries.

Secondary Outcome Measures

Name	Time	Method
Change in relative abundance of gut microbial taxa	Baseline and 90 days	Change in the relative abundance of selected bacterial genera associated with constipation and Parkinson's disease, measured by 16S rRNA sequencing of stool samples.

Trial Locations

Locations (1)

Hospital de Clínicas de Porto Alegre (HCPA); 🇧🇷 Porto Alegre, Rio Grande do Sul, Brazil