Parkinsons Disease (PD)NUTRI-GUT-PDNCT07213856
Nutritional Intervention for Constipation Symptoms in Patients With Parkinson's Disease
A study testing Dietitian-Guided Nutritional Intervention in people with Parkinsons Disease (PD) and Constipation - Functional, run by Hospital de Clinicas de Porto Alegre at 1 site in Brazil.
Trial 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… Read more about this study
- Who is it for?
- Ages 18 years and older
- Conditions the study is for
- Parkinsons Disease (PD), Constipation - Functional
- What is being tested?
- Dietitian-Guided Nutritional Intervention
- Type of treatment
- Lifestyle or therapy programme
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 54 participants
- Where
- 1 siteBrazil
- Study dates
- 2 Apr 2026to Aug 2029
- Phase
- Interventional
- Are there results?
- Not yet: the study is under way
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 18 years and older
- All sexes
- No healthy volunteers
- Adult, Older adult
Who may be able to join
- 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
Who cannot join
- 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
Show all 13Show fewer
- 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
Trial locations and contacts
1 site in 1 country. Contact the study team or a site near you to ask about taking part.
Brazil1 site, 1 recruiting
- Recruiting
Hospital de Clínicas de Porto Alegre (HCPA)
Porto Alegre, Rio Grande do Sul
Maira Rozenfeld Olchik, PhD, +55 (51) 33083020, molchik@hcpa.edu.br
Juliana Heitich Brendler, Msc
About this study
Official title: Nutritional Intervention for Constipation Symptoms in Patients With Parkinson's Disease: A Randomized Clinical Trial
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?
Read more
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
- Conditions
- Parkinsons Disease (PD), Constipation - Functional
- Being tested
- Dietitian-Guided Nutritional Intervention
- Keywords
- Microbiota, Diet, Diet, Protein-Restricted, Diet Therapy, Diet, Healthy, Nutrition Therapy, Constipation, Non-Motor Symptoms, Nutritionists
- Medical subject headings
- Parkinson Disease, Constipation
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Dietitian-Guided Nutritional InterventionBehavioural
Also called Diet plan
Participants receive a diet plan and nutritional counseling provided by a registered dietitian, based on a standardized protocol aligned with the Dietary Reference Intakes (DRIs) and adapted for the management of Parkinson's disease and constipation. The intervention includes follow-ups with the dietitian over a 3-month period.
| Study group | Role | What they receive |
|---|---|---|
| Nutritional Intervention Group | Experimental | Participants will receive a tailored diet plan made by a registered dietitian, with follow-ups for 3 months. The plan is based on Dietary Reference Intakes and adapted to Parkinson's disease and constipation management guidelines. Receives: Behavioral: Dietitian-Guided Nutritional Intervention |
| Control Group | No intervention | Participants will not receive individualized nutritional support during the study period. They will receive the dietary guidance only after the end of the study (3 months). |
What is being measured
The primary outcome is the main question the study is designed to answer.
Change in weekly bowel movement frequency
Mean change in the number of spontaneous bowel movements per week from baseline to 12 weeks, based on participant-reported bowel diaries.
Measured: Baseline and 90 days
Secondary outcomes (1)
Change in relative abundance of gut microbial taxa
Change in the relative abundance of selected bacterial genera associated with constipation and Parkinson's disease, measured by 16S rRNA sequencing of stool samples.
Measured: Baseline and 90 days
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted9 Oct 2025
- Study start2 Apr 2026
- Primary completionJun 2027 (estimated)
- Study completionAug 2029 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Publications (5)Papers the sponsor has linked to this study.
- Other trials for Parkinsons Disease (PD)Studies of the same condition, open and under way.
- More trials run by Hospital de Clinicas de Porto AlegreThe sponsor's other registered studies.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase N/A
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- Single blind
- Who is masked
- Outcomes assessor
- Enrolment
- 54 participants (estimated)
Sponsor and investigators
- Lead sponsor
- Hospital de Clinicas de Porto Alegre
- Sponsor type
- University, hospital or other
- Responsible party
- Sponsor
- Investigators
- Maira Rozenfeld Olchik, PhD, Principal investigator, Federal University of Rio Grande do Sul
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT07213856
- Sponsor's protocol ID
- 2025-0374
- Acronym
- NUTRI-GUT-PD
- Status last verified
- Jun 2026
- First submitted
- 2 Oct 2025
- Last updated
- 16 Jun 2026
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- No
Publications
National Academies of Sciences, Engineering, and Medicine; Health and Medicine Division; Food and Nutrition Board; Committee on the Dietary Reference Intakes for Energy. Dietary Reference Intakes for Energy. Washington (DC): National Academies Press (US); 2023 Jan 17. Available from http://www.ncbi.nlm.nih.gov/books/NBK588659/
PubMed 36693139Barichella M, Cereda E, Cassani E, Pinelli G, Iorio L, Ferri V, Privitera G, Pasqua M, Valentino A, Monajemi F, Caronni S, Lignola C, Pusani C, Bolliri C, Faierman SA, Lubisco A, Frazzitta G, Petroni ML, Pezzoli G. Dietary habits and neurological features of Parkinson's disease patients: Implications for practice. Clin Nutr. 2017 Aug;36(4):1054-1061. doi: 10.1016/j.clnu.2016.06.020. Epub 2016 Jul 5.
PubMed 27406858Drossman DA, Hasler WL. Rome IV-Functional GI Disorders: Disorders of Gut-Brain Interaction. Gastroenterology. 2016 May;150(6):1257-61. doi: 10.1053/j.gastro.2016.03.035. No abstract available.
PubMed 27147121Postuma RB, Berg D, Stern M, Poewe W, Olanow CW, Oertel W, Obeso J, Marek K, Litvan I, Lang AE, Halliday G, Goetz CG, Gasser T, Dubois B, Chan P, Bloem BR, Adler CH, Deuschl G. MDS clinical diagnostic criteria for Parkinson's disease. Mov Disord. 2015 Oct;30(12):1591-601. doi: 10.1002/mds.26424.
PubMed 26474316Brendler JH, da Silva KY, Dall'Alba V, Martins AF, Teixeira-Dos-Santos D, Schuh AFS, Olchik MR. Dietitian-led intervention to manage constipation in Parkinson's disease: Study protocol for a parallel-group randomized controlled trial (NUTRI-GUT-PD). PLoS One. 2026 Jul 27;21(7):e0354608. doi: 10.1371/journal.pone.0354608. eCollection 2026.
PubMed 42507749
Study at a glance
From the registry record, last updated by the sponsor on 16 Jun 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Nutritional Intervention for Constipation Symptoms in Patients With Parkinson's Disease: A Randomized Clinical Trial
- ClinicalTrials.gov ID
- NCT07213856
- Acronym / sponsor ID
- NUTRI-GUT-PD / 2025-0374
- Conditions
- Parkinsons Disease (PD), Constipation - Functional
- Keywords
- Microbiota, Diet, Diet, Protein-Restricted, Diet Therapy, Diet, Healthy, Nutrition Therapy, Constipation, Non-Motor Symptoms
- Study type
- Interventional
- Recruitment status
- Recruiting
- Enrolment
- 54 participants (estimated)
- Lead sponsor
- Hospital de Clinicas de Porto AlegreUniversity, hospital or other
- Study start
- 2 Apr 2026 (actual)
- Primary completion
- Jun 2027 (estimated)
- Study completion
- Aug 2029 (estimated)
- First posted
- 9 Oct 2025 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
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
Study design
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- Single blind (outcomes assessor)
- Number of arms
- 2
| Arm | Type | Receives |
|---|---|---|
| Nutritional Intervention Group | Experimental | Behavioral: Dietitian-Guided Nutritional InterventionParticipants will receive a tailored diet plan made by a registered dietitian, with follow-ups for 3 months. The plan is based on Dietary Reference Intakes and adapted to Parkinson's disease and constipation management guidelines. |
| Control Group | No intervention | –Participants will not receive individualized nutritional support during the study period. They will receive the dietary guidance only after the end of the study (3 months). |
Who may qualify
- Ages
- 18 years and older
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Adult, Older adult
Key inclusion criteria (3 listed)
- 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
Key exclusion criteria (13 listed)
- 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
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| Dietitian-Guided Nutritional InterventionAlso: Diet planParticipants receive a diet plan and nutritional counseling provided by a registered dietitian, based on a standardized protocol aligned with the Dietary Reference Intakes (DRIs) and adapted for the management of Parkinson's disease and constipation. The intervention includes follow-ups with the dietitian over a 3-month period. | Behavioural | Nutritional Intervention Group |
Primary outcome
Change in weekly bowel movement frequency
Time frame: 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.
1 secondary outcome
Change in relative abundance of gut microbial taxa
Time frame: Baseline and 90 days
Results and safety
This study is still under way. Results are not available in the source record yet.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 16 Jun 2026.
- Background: PubMed 36693139National Academies of Sciences, Engineering, and Medicine; Health and Medicine Division; Food and Nutrition Board; Committee on the Dietary Reference Intakes for Energy. Dietary Reference Intakes for Energy. Washington (DC): National Academies Press (US); 2023 Jan 17. Available from http://www.ncbi.nlm.nih.gov/books/NBK588659/
- Background: PubMed 27406858Barichella M, Cereda E, Cassani E, Pinelli G, Iorio L, Ferri V, Privitera G, Pasqua M, Valentino A, Monajemi F, Caronni S, Lignola C, Pusani C, Bolliri C, Faierman SA, Lubisco A, Frazzitta G, Petroni ML, Pezzoli G. Dietary habits and neurological features of Parkinson's disease patients: Implications for practice. Clin Nutr. 2017 Aug;36(4):1054-1061. doi: 10.1016/j.clnu.2016.06.020. Epub 2016 Jul 5.
- Background: PubMed 27147121Drossman DA, Hasler WL. Rome IV-Functional GI Disorders: Disorders of Gut-Brain Interaction. Gastroenterology. 2016 May;150(6):1257-61. doi: 10.1053/j.gastro.2016.03.035. No abstract available.
- Background: PubMed 26474316Postuma RB, Berg D, Stern M, Poewe W, Olanow CW, Oertel W, Obeso J, Marek K, Litvan I, Lang AE, Halliday G, Goetz CG, Gasser T, Dubois B, Chan P, Bloem BR, Adler CH, Deuschl G. MDS clinical diagnostic criteria for Parkinson's disease. Mov Disord. 2015 Oct;30(12):1591-601. doi: 10.1002/mds.26424.
- Derived from this study: PubMed 42507749Brendler JH, da Silva KY, Dall'Alba V, Martins AF, Teixeira-Dos-Santos D, Schuh AFS, Olchik MR. Dietitian-led intervention to manage constipation in Parkinson's disease: Study protocol for a parallel-group randomized controlled trial (NUTRI-GUT-PD). PLoS One. 2026 Jul 27;21(7):e0354608. doi: 10.1371/journal.pone.0354608. eCollection 2026.
- Individual participant dataSharing planned: No
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Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part.
Maira Rozenfeld Olchik, PhD principal investigator
Federal University of Rio Grande do Sul
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A study testing Dietitian-Guided Nutritional Intervention in people with Parkinsons Disease (PD) and Constipation - Functional, run by Hospital de Clinicas de Porto Alegre at 1 site in Brazil.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 3 inclusion and 13 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: looking for participants now, as of the sponsor's last update on 16 Jun 2026. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 1 site in Brazil. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
Are results available for this study?
This study is still under way. Results are not available in the source record yet.
How can a doctor refer a patient or contact the research team?
Contact Maira Rozenfeld Olchik, PhD (+55 (51) 33083020, molchik@hcpa.edu.br), or a site near the patient. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Change in weekly bowel movement frequency (time frame: Baseline and 90 days). It is what the study was designed to measure, not a finding.
Where can I read the original study information?
On the ClinicalTrials.gov record for NCT07213856, which also lists 5 linked publications.
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 16 Jun 2026.