Patient case (clinical description): A 70-year-old man comes to the office accompanied by his wife.  The patient has experienced progressive memory loss over the last years.  He needs help with some of his routine activities, such as paying bills.  The patient's wife says, "He used to be such an independent person, but now he needs help with many things, even finding direction to home!"  Medical history includes hypertension, hyperlipidemia, and type 2 diabetes mellitus.  Family history includes Alzheimer disease in his father.  MRI reveals diffuse cortical and hippocampal atrophy. The diagnosis of AD is made using the National Institute on Aging and the Alzheimer's Association (NIA-AA) criteria.

Patient's own account: I am a 70-year-old man, and I paid a visit to the doctor with my wife the other day. I noticed that I tend to forget small things and that my memory has decreased over the past few years. I even ask my wife to help me out with my daily routine. I used to be the one paying the bills, but now she has to give me a hand. My wife mentioned to the doctor that I used to be independent and that I tend to forget where we live. I suffer from hypertension, high cholesterol, and type 2 diabetes. My poor dad was suffering from Alzheimer disease, so I hope I'm not going to end the same way! I did an MRI and they found out that some part of my brain was decreasing. I also did an Alzheimer test.

Clinical trial: Exploration of the Enteric Nervous System in Alzheimer Disease

Eligibility criteria:
Inclusion Criteria:

          -  For the 3 groups of patients : colonoscopy planned by a gastroenterologist in the
             context ot the usual medical follow-up of the patient

        For patients with Alzheimer's disease :

          -  Patient with early to moderate Alzheimer disease (continuum of patients with mild
             cognitive impairment due to Alzheimer's disease and patients diagnosed with probable
             Alzheimer's disease) according to the National Institute of Aging-Alzheimer's
             Association (NIA AA) criteria

          -  Mini-Mental State Examination (MMSE) score ≥18;

          -  Has one informant or care partner;

          -  No parkinsonian syndrome

          -  No sign of lewy Body dementia

        For patients with Parkinson's disease:

          -  patients with Parkinson Disease according to the United Kingdom Parkinson's Disease
             Society Brain Bank (UKPDSBB) criteria

          -  No dementia sign or cognitive deficit associated to Alzheimer's disease

        For patients without neurodegenerative disease:

          -  No history or current neurological/degenerative condition (e.g, lewy body dementia,
             Parkinson's disease, Parkinsonian syndrome, Alzheimer's disease,…)

          -  No memory complaint with a Mac Nair score ≤15

          -  MMSE score ≥28 ;

          -  Patient at risk of colic cancer with a colonoscopy scheduled

        Exclusion Criteria:

        For the 3 groups of patients : :

          -  History of colonic disorder ((e.g inflammatory condition, adenocarcinoma)

          -  contra-indications to colonoscopy

        For patients with Alzheimer's disease and for patients with Parkinson's disease:

        - Any neurological/neurodegenerative condition different from the group to which it belongs
        (e.g other than Alzheimer's disease for Alzheimer's disease group or other than Parkinson's
        disease for Parkinson's disease group….)

        For patients without neurodegenerative disease:

          -  Any neurological/neurodegenerative condition (e.g lewy body dementia, Parkinsonian
             syndrome, Parkinson's disease, Alzheimer's disease..)..

          -  functional colopathy
No condition on gender to be admitted to the trial.
Accepts Healthy Volunteers
Subject must be at least 50 Years old.
Subject must be at most 80 Years

Eligibility (NLI label): Entailment