Mechanisms Underlying the Blood Pressure Lowering Effect of Sleep

Study Overview
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Brief Summary
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The main purpose of this study is to learn about the influence of two different behavioral interventions (lasting 8 weeks) involving sleep for lowering blood pressure, and to study the mechanisms involved. There is research evidence that healthy sleep promotes heart-health and may decrease blood pressure, and that sensitivity to insufficient or disrupted sleep may be influenced by sex. This research will compare two interventions that are each designed to improve sleep health, and will investigate sex differences in response. The project includes 3 in-hospital stays with biological measurements to evaluate the underlying mechanisms associated with the effectiveness of two different blood pressure lowering behavioral interventions.

Detailed Description
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The study involves home-based sleep-wake data collection before and during behavioral intervention, and 3 overnight stays in the hospital. For each hospital stay participants will be asked to arrive in the afternoon, and stay until the next evening. They will be provided dinner on the first day and breakfast, lunch and dinner on the second day. If they are taking any blood pressure medication they will continue to take it through the study. During the in-hospital stays, blood pressure will be measured continuously using two small finger cuffs. In order to monitor and record brain waves to determine sleep and wakefulness, small gold-coated disks called electrodes will be placed on the head and body. Heart rate, blood pressure and brain activity will be recorded for a little over 24 hours on each in-hospital stay. Before as well as during the in-hospital stays questions will be asked about sleep times, subjective sleepiness and other indices relating to well-being.

Official Title
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Mechanisms Underlying the Blood Pressure Lowering Effect of Sleep Extension

Conditions
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Hypertension

Intervention / Treatment
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* Behavioral: Sleep Extension
* Behavioral: Sleep Timing


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: pre-hypertension or stage one hypertension (BP ≥120/80 and <160/100). usual sleep period occurs at night Exclusion Criteria: significant active or uncontrolled sleep disorders shiftwork current pregnancy diabetic patients who are insulin dependent (or have HbA1c>9.0%) current use of hypnotics or clonidine renal/electrolyte disorders and any other condition that the study screening physician considers would significantly impede participation in the study

Ages Eligible for Study
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Minimum Age: 25 Years
Maximum Age: 70 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: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Double


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: Sleep Timing<br>Intervention will include basic education concerning sleep hygiene and regularity of sleep timing | Behavioral: Sleep Timing<br>* Regularize the timing of the sleep period.<br>|
| Experimental: Sleep Extension<br>Intervention will include basic education concerning sleep hygiene and an extension of the sleep period. | Behavioral: Sleep Extension<br>* Lengthen the duration of sleep time.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Reduction in 24 hour blood pressure | 24h blood pressure (daily averaged). | The primary outcome measure will be measured during 3 hospital visit periods of approximately 28 hours each. The primary outcome will be evaluated based on an 8 week behavioral intervention. | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Lowering of sleep period blood pressure | Blood pressure during day wake period minus blood pressure at night during sleep period | he primary outcome measure will be measured during 3 hospital visit periods ofThe secondary outcome will be evaluated based on an 8 week behavioral intervention. |