Effect of Total Sleep Deprivation on Vascular Function

Study Overview
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Brief Summary
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Insufficient sleep is associated with an increased risk for cardiovascular disease. The causal mechanisms are currently unknown, but may include endothelial dysfunction. The purpose of this study is to examine the influence of sex and aging on the effects of total sleep deprivation on vascular function and whether exercise training attenuates these effects.

Official Title
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Effect of Total Sleep Deprivation on Vascular Function

Conditions
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Sleep Deprivation

Intervention / Treatment
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* Other: Exercise
* Other: Supervised Total Sleep Deprivation


Participation Criteria
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Eligibility Criteria
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Inclusion criteria: Males and females 20 to 30 and 50 to 60 years of age Females will be eumenorrheic at enrollment or postmenopausal for at least 1 year No major clinical disease (e.g., diabetes, cardiovascular, liver or chronic kidney disease) to minimize confounding of vascular measures Participants will be sedentary (≤3x per week of ≤30 minutes of aerobic exercise/session) or trained (≥5x per week of moderate/vigorous aerobic exercise training) Exclusion criteria: Age <20 or 31 to 49 or >60 years Body mass index ≥30 kg/m^2 because obesity may affect vascular function Use of medication that may affect vascular measures Hormone replacement therapy or hormonal contraceptives within past year Use of tobacco products (chewing tobacco, traditional or e-cigarettes) because they may influence vascular function Being perimenopausal, pregnant or lactating because may influence vascular function Being a shift worker because habitual sleep deprivation and altered circadian rhythm may influence vascular function. Not having an intermediate chronotype based on the Morningness-Eveningness Questionnaire (MEQ; score <31 or >69) because this would influence the effect of overnight sleep deprivation on vascular function. Sleep complaints based on the Pittsburgh Sleep Quality Index (PSQI; score >5) because this would influence the effect of overnight sleep deprivation on vascular function.

Ages Eligible for Study
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Minimum Age: 20 Years
Maximum Age: 60 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: Basic Science
Allocation: Randomized
Intervention Model: Crossover Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Group A<br>Participants will have vascular function assessed following total sleep deprivation | Other: Supervised Total Sleep Deprivation<br>* Laboratory-monitored total sleep deprivation<br>|
| No Intervention: Group B<br>Participants will have vascular function assessed following a full night of sleep | |
| Experimental: Group C<br>Participants will have vascular function assessed following total sleep deprivation preceded by exercise | Other: Exercise<br>* 60 minutes of moderate-intensity treadmill exercise (70% of maximal heart rate determined from the maximal graded exercise test)<br>Other: Supervised Total Sleep Deprivation<br>* Laboratory-monitored total sleep deprivation<br>|
| No Intervention: Group D<br>Participants will have vascular function assessed following a full night of sleep | |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Endothelial function | Endothelial function will be determined using brachial artery flow-mediated dilation via high resolution duplex ultrasonography. Reactive hyperemia will be produced by inflating a forearm cuff to  250 mmHg for 5 minutes followed by rapid deflation. | through study completion, an average of 1 month | 
| Microvascular function | Microvascular function will be assessed using the forearm blood flow response to submaximal handgrip exercise. Brachial artery blood flow and diameter will be assessed using Doppler ultrasound. | through study completion, an average of 1 month | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Central arterial stiffness | The SphygmoCor XCEL device will be used to measure carotid to femoral pulse wave velocity. | through study completion, an average of 1 month | 
| Central arterial hemodynamics | The SphygmoCor XCEL device will be used to obtain central pulse wave analysis. | through study completion, an average of 1 month |