NCT05934188 · RECRUITING

Exploring the Gut-Brain Axis in Ageing and Neurodegeneration

This observational study is mapping connections between gut bacteria and brain health across several conditions, including prodromal Alzheimer's disease, Parkinson's, and multiple sclerosis. Participants get an MRI, stool and blood tests, cognitive assessments, and diet questionnaires. No drugs or treatments are involved. Because no phase is listed, this is early exploratory research — the goal is to find patterns, not to test a therapy.

Eligibility criteria

INCLUSION CRITERIA:
Healthy Young and Old Subjects:
* 20-50 or 60-90 years old
* Cognitively healthy (Mini-Mental State examination ≥ 26)
* Absence of significant neurological disorders
Patients with prodromal Alzheimer's Disease:
* Subjective cognitive complaint (corroborated by the informant)
* Episodic memory deficit on neuropsychological testing
* Clinical Dementia Rating = 0.5
* Mini-Mental State Examination (MMSE) > 23
* Independently functioning in activities of daily living
Patients with Parkinson's Disease:
* Recent diagnosis of Parkinson's Disease
* Mild-moderate score at the Unified Parkinson's Disease Rating Scale (UPDRS)
* Cognitively healthy (Mini-Mental State examination ≥ 26)
* In case of taking medications for Parkinson's Disease: stable dosage for at least 6 months
Patients with Multiple Sclerosis:
* Recent diagnosis of relapsing-remitting Multiple Sclerosis
* Expanded Disability Status Scale score ≤ 4.0
* Cognitively healthy (Mini-Mental State examination ≥ 26)
* In case of taking medications for Multiple Sclerosis: stable dosage for at least 6 months.
EXCLUSION CRITERIA:
For both healthy participants and patients:
* Contraindications to magnetic resonance imaging (metal implant in body, known claustrophobia, pacemakers)
* Severe comorbidities
* Antibiotics treatments over the last 3 months

The sponsor's own eligibility wording, lightly reformatted. The study team makes the final eligibility decision — worth discussing with your doctor.

Eligibility criteria as of 2026-01-09

View full record on ClinicalTrials.gov

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