Association Between Cerebral Arterial Vascular Flow and Sleep Apnea in Neurodegenerative Alterations

Study Overview
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Brief Summary
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Obstructive sleep apnea syndrome (OSAS) is a sleep-disordered breathing characterized by the occurrence of repeated upper airway obstructions leading to airflow reduction (hypopnea) or cessation (apnea). The apnea-hypopnea index (AHI) is the number of apneas and hypopneas per hour of sleep. OSA patients often report cognitive complaints. About 25% of the elderly population is affected by this syndrome with a drastic increase of this rate among dementia patients. OSAS is considered to be an important risk factor for the development of hypertension, heart disease and stroke.

Detailed Description
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Numerous studies pointed out the close relationship between sleep apnea and cognitive impairment. To the investigators' knowledge, no trials have assessed the existence of a relationship between the IAH index and the cerebral arterial blood flow rate (macrocirculation). Developments in magnetic resonance imaging (MRI) provide new insights into the quantitative study of blood flow through phase contrast MRI also called flow MRI. The main hypothesis tested in this study is the existence of a relationship between OSAS and total cerebral arterial vascular inflow measured by PC-MRI (in mL/min) in the elderly population. Primary outcome: The apnea/hypopnea index (measured by nocturnal respiratory polygraphy) and total arterial flow rate (measured by PC-MRI) Secondary outcomes: Measurement of arrhythmia Measurement of arterial blood pressure

Official Title
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Association Between Cerebral Arterial Vascular Flow and Sleep Apnea in Neurodegenerative Alterations

Conditions
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Alzheimer Disease

Intervention / Treatment
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* Other: Vascular flow measurement by PC-MRI


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Elderly patients about or over 75 years Any gender Dementia Group: 3.1. MMSE (Mini Mental State Examination)> 15 3.2. Diagnosis of dementia established according to DSM-IV 3.3. Dementia of the Alzheimer type from NINCDS-ADRDA (National Institute of Neurological and Communicative Disorders and Stroke and the Alzheimer's Disease and Related Disorders Association) Control Group: Preserved cognitive function corresponding to a normal MMSE score by the standards of Poitrenaud Ability to understand and give consent freely (for demented subjects, a legal representative will be delegate) Exclusion Criteria: Elderly patients under 75 years Anyone with a classic contraindication to MRI 2.1 Major behavioral disorders that do not allow the realization of MRI in optimal conditions 2.2 Claustrophobia 2.3 Presence of foreign non-compliant material 2.4 Presence of intraocular metal body Having a history of chest surgery or neurosurgical Chronic respiratory failure Suffering from dementia other than that associated with Alzheimer's disease Patients with a handicap Patients under legal protection

Ages Eligible for Study
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Minimum Age: 75 Years
Maximum Age: 120 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

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
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Dementia group<br>Assessed by the insertion of an interaction parameter between cerebral blood flow and the group label(dementia or no-dementia). ROC method will be used to find a threshold value of IAH that separates the two groups. Interventions: Vascular flow measurement by PC-MRI Neuropsychological assessment Registration of sleep apnea Registration of blood pressure ECG holters Blood test Geriatric standard evaluation | Other: Vascular flow measurement by PC-MRI<br>* participants will undergo vascular flow measurement by PC-MRI at intra and extracranial levels<br>|
| Other: control group<br>Assessed by the insertion of an interaction parameter between cerebral blood flow and the group label(dementia or no-dementia). ROC method will be used to find a threshold value of IAH that separates the two groups. Interventions: Vascular flow measurement by PC-MRI Neuropsychological assessment Registration of sleep apnea Registration of blood pressure ECG holters Blood test Geriatric standard evaluation | Other: Vascular flow measurement by PC-MRI<br>* participants will undergo vascular flow measurement by PC-MRI at intra and extracranial levels<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Total arterial flowrate (measured by PC-MRI debit ml/Mn) |  | at day 1 after inclusion | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| sleep apnea measured by elderly polygraphy (Number of apneas / night) |  | at day 1 after inclusion up to 24 heures | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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sleep apnea, phase-contrast MRI, cerebral blood flow, vascular risk factor, dementia