Taxonomic and Functional Composition of the Intestinal Microbiome: a Predictor of Rapid Cognitive Decline in Patients With Alzheimer's Disease

Study Overview
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Brief Summary
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The objective of the study is to highlight a modification of the composition of the intestinal microbiota associated with the diagnosis of Alzheimer's disease and its most unfavorable form, Rapid Cognitive Decline (DCR). This identification could lead to diagnostic strategies based on the analysis of the intestinal microbiome, and preventive and curative treatments, based on the modulation of intestinal microbiota

Official Title
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Taxonomic and Functional Composition of the Intestinal Microbiome: a Predictor of Rapid Cognitive Decline in Patients With Alzheimer's Disease

Conditions
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Alzheimer Disease, Intestinal Microbiota

Intervention / Treatment
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* Procedure: Fecal sample collection


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: For Alzheimer groups without DCR and Alzheimer with DCR: patients between 70 and 90 years old with mild to moderate Alzheimer's disease (MMSE> 15/30), followed in the CMRR of the University Hospital of Nantes or Angers having given their informed consent For the control group (non-Alzheimer's) more patients between 70 and 90 years consultant for a subjective memory complaint isolated at the CMRR of Nantes or Angers University Hospital, having given their informed consent Exclusion Criteria: Major patients under tutorship, curatorship or safeguard of justice Cognitive disorders possibly related to a metabolic or psychiatric cause History of prescription of antibiotic treatment in the last month History of acute gastrointestinal illness in the last month History of hospitalization for an acute medical pathology or for a surgical procedure in the last month

Ages Eligible for Study
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Minimum Age: 70 Years
Maximum Age: 90 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Diagnostic
Allocation: Non-Randomized
Intervention Model: Parallel Assignment
Interventional Model Description: The study will compare three groups of 100 patients, corresponding to 200 patients with Alzheimer disease (whom 100 patients in the rapid cognitive decline group and 100 patients without rapid cognitive decline) and 100 patients in the control group.
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Alzheimer with rapid DCR<br> | Procedure: Fecal sample collection<br>* Fecal sample collection<br>|
| Experimental: Alzheimer without rapid DCR<br> | Procedure: Fecal sample collection<br>* Fecal sample collection<br>|
| Sham Comparator: Control<br> | Procedure: Fecal sample collection<br>* Fecal sample collection<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| analysis of the taxonomic and functional composition of the microbiome | (shotgun sequencing), in patients with DCR (loss of at least 3 points in the MMSE at 1 year. | 1 year | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| to determine if there is a specific modification of the composition of the intestinal microbiota of patients with Alzheimer's disease, compared to control group. |  | Day 0 | 
| create a prognostic score of DCR based on clinical data, including the responses to the MMSE, BREF and MNA questionnaires, and taking into account the microbiota analysis |  | 1 year |