Effect of Hypoxic Conditioning on Cerebrovascular Health in the Elderly

Study Overview
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Brief Summary
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In line with the ever-growing aging of Western populations, the development of preventive strategies to slow down the effects of aging on cardiovascular health represents a major challenge in order to preserve functional capacities and a sufficient quality of life in the elderly. The alteration of vascular function (at the cerebral and systemic level) with aging is an important feature in the clinical picture including a decrease in physical and cognitive capacities. Although physical activity is recognized as an essential means of combating the effects of aging, optimizing its effects by defining the most effective strategies of practice remains a key objective. Offering alternative interventions to exercise training is also necessary for people who are unwilling or unable to engage in a physical activity program. In this context, hypoxic conditioning, alone or in conjunction with rehabilitative exercise training, is a new therapeutic modality with strong preclinical validity, in particular from a cardiovascular standpoint, and used in other pathologies to improve cardiovascular function and exercise performance and quality of life. Our aim is, therefore, to investigate the effect of hypoxic conditioning (alone or in conjunction with exercise training) on cerebrovascular health in the elderly.

Official Title
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Effect of Hypoxic Conditioning on Cerebrovascular Health in the Elderly

Conditions
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Hypoxia, Cerebral Hypoxia, Brain Diseases, Exercise, Aging, Cognitive Decline, Healthy Aging

Intervention / Treatment
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* Procedure: Hypoxia and/or Exercise


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: 60 to 80 years of age; Being physically inactive (less than 150 min/week of moderate to intense physical activity); No chronic cardiovascular, respiratory, metabolic or neuromuscular disease counterindicating an exercise training or hypoxic conditioning program; Health coverage; Being able to provide written fully informed consent. Exclusion Criteria: Body-mass index >30 kg/m2; Smoking (> cigarettes/day); Alcohol use (> 10g/day); Mental disorder or history of mental disorder; Beta-blockade treatment; Inability or refusal to provide informed consent; No health coverage People exceeding the annual ceiling of allowances received as a result of their participation in other clinical trials; People deprived of freedom by judicial or administrative decision; People subject to legal protection, who cannot be included in clinical trials.

Ages Eligible for Study
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Minimum Age: 60 Years
Maximum Age: 80 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: Prevention
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Quadruple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Hypoxia - Rest<br>Sessions of intermittent hypoxia at rest; 3 sessions/week; 8 weeks. To be compared with the placebo (normoxia) group at rest. | Procedure: Hypoxia and/or Exercise<br>* Hypoxia at rest versus normoxia at rest; Hypoxia during exercise versus Normoxia during exercise.<br>|
| Placebo Comparator: Normoxia - Rest<br>Sessions of normoxia at rest; 3 sessions/week; 8 weeks. | Procedure: Hypoxia and/or Exercise<br>* Hypoxia at rest versus normoxia at rest; Hypoxia during exercise versus Normoxia during exercise.<br>|
| Experimental: Hypoxia - Exercise<br>Sessions of exercise training under hypoxia; 3 sessions/week; 8 weeks. To be compared with the placebo (exercise under normoxia) group. | Procedure: Hypoxia and/or Exercise<br>* Hypoxia at rest versus normoxia at rest; Hypoxia during exercise versus Normoxia during exercise.<br>|
| Active Comparator: Normoxia - Exercise<br>Sessions of exercise training under hypoxia; 3 sessions/week; 8 weeks. | Procedure: Hypoxia and/or Exercise<br>* Hypoxia at rest versus normoxia at rest; Hypoxia during exercise versus Normoxia during exercise.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Middle cerebral artery flow velocity | Changes in middle cerebral artery flow velocity in response to hypercapnia (5% CO2) | Before intervention; right after intervention; 2 months after intervention | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Peak oxygen uptake | Peak oxygen uptake during a cardiopulmonary exercise test | Before intervention; right after intervention; 2 months after intervention | 
| Flow-mediated dilation | Flow-mediated dilation in response to ischemia-reperfusion of the brachial artery | Before intervention; right after intervention; 2 months after intervention | 
| Blood pressure | 24h (systolic, diastolic and mean) blood pressure assessment | Before intervention; right after intervention; 2 months after intervention | 
| Sleep | Sleep features assessed by polygraphy | Before intervention; right after intervention; 2 months after intervention | 
| Cognitive function | Cognitive function assessed by the Montreal Cognitive Assessment questionnaire | Before intervention; right after intervention; 2 months after intervention | 
| Health-related quality of life | Health-related quality of life assessed by the SF-36 questionnaire | Before intervention; right after intervention; 2 months after intervention |