Social Experiences and Sleep Study

Study Overview
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Brief Summary
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This study will test the effect of race-based social rejection on polysomnography derived sleep outcomes and nocturnal cardiovascular psychophysiology in a sample of 80 African Americans and 80 Caucasian Americans. The investigators will test group differences on these outcomes as well as within subjects by testing impact of rejection compared to a non-rejection control night in the sleep laboratory.

Detailed Description
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African Americans (AA) are disproportionally burdened by cardiovascular disease compared to Caucasian Americans (CA). Poor sleep, which is more common among AA, may serve as an important pathway in understanding these disparities. Race-based rejection has been cross-sectionally related to poor sleep and negative cardiovascular outcomes. To test the links between social experiences and sleep, participants will spend two nights in the sleep laboratory. One night will be a control night where participants complete low arousal tasks prior to bedtime. On a second night, the investigators will randomize 80 AA and 80 CA to either race-based social rejection (i.e., being rejected by an out-group member) or same-race social rejection prior to bedtime to test the causal influences of race-based rejection on objective sleep parameters, measured using polysomnography, and nocturnal cardiovascular functioning. The investigators will test group differences on these outcomes as well as within subjects by testing impact of rejection compared to a non-rejection control night in the sleep laboratory. The order of the control and rejection task night will be counterbalanced.

Official Title
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The Effects of Social Experiences on Sleep and Cardiovascular Functioning

Conditions
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Sleep, Blood Pressure

Intervention / Treatment
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* Behavioral: Social rejection


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Age: 18 to 64 years old Self-identified as African American/Black or Caucasian American/White English speaking, able to provide consent Self-reported bedtime between 10PM and 12AM for 5/7 nights for the past 3 months (stability to be confirmed by sleep diary and wrist actigraphy). Self-reported sleep duration between 6.5 and 8.5 hours for 5/7 nights for the last month (duration to be confirmed by actigraphy and sleep diary) Exclusion Criteria: Body mass index of 40 or above Participants at high risk for obstructive sleep apnea, based on high risk score from the STOP-Bang. Medical or psychiatric condition, as assessed by self-report and clinical interview that affect sleep and/or cardiovascular functioning, including doctor diagnosed arrhythmia, hypertension, congestive heart failure, major depression, bipolar disorder, post-traumatic stress disorder. Medication use that is likely to affect sleep and/or cardiovascular functioning, including antidepressants, anxiolytic or soporific medication, and beta-blockers.

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 64 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: Factorial Assignment
Interventional Model Description: All participants will complete two nights in the sleep laboratory. One night will be a non-rejection control night. The other night will be a rejection task night. In this regard, African American and Caucasian American participants will be randomized to one of two conditions. All participants will be exposed to social rejection prior to bedtime; however, they will either be rejected by a person of their own race (in-group member) or a different race (out-group member)
Masking: Double


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Social rejection by in-group<br>One hour prior to bed, participants will be exposed to a social rejection paradigm that includes a computerized ball-tossing game (Cyberball) and a speech task. Participants are made to believe that they are being rejected by someone of their own race/ethnicity (e.g., African American rejected by another African American). | Behavioral: Social rejection<br>* Social rejection paradigm<br>|
| Experimental: Social rejection by out-group<br>One hour prior to bed, participants will be exposed to a social rejection paradigm that includes a computerized ball-tossing game (Cyberball) and a speech task. Participants are made to believe that they are being rejected by someone not of their own race/ethnicity (e.g., Caucasian American rejected by another African American). | Behavioral: Social rejection<br>* Social rejection paradigm<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in sleep onset latency, as determined by polysomnography | Sleep onset latency is the time (in minutes) from lights out to sleep onset on the nights following the social rejection task and the control task laboratory to onset of sleep, as measured via polysomnography | Assessed on the night of the social rejection task and compared to the control task night; it is anticipated that these nights will take place consecutively | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in minutes of wake after sleep onset (WASO), as determined by polysomnography | Number of minutes awake once sleep is initiated, measured via polysomnography on the nights following the social rejection task and the control task | Assessed on the night of the social rejection task and the night of the control task; it is anticipated that these nights will take place consecutively | 
| Change in total sleep time, as determined by polysomnography | Total number of minutes scored as sleep, measured via polysomnography on the nights following the social rejection task and the control task | Assessed on the night of the social rejection task and the night of the control task; it is anticipated that these nights will take place consecutively | 
| Change in pre-ejection period (PEP) in response to rejection task | Pre-ejection period is measured via impedance cardiography, averaged over a 5-minute baseline period and in the minutes during the rejection task | Baseline to Post-rejection task, anticipated average of 30 minutes | 
| Change in heart rate variability (HRV) in response to rejection task | Heart rate variability is measured via EKG, averaged over a 5-minute baseline period and in the minutes during the rejection task | Baseline to Post-rejection task, anticipated average of 30 minutes | 
| Change in nocturnal heart rate variability | Heart rate variability is measured via EKG, beginning at lights out and collected across the night following the rejection task and control task; it is anticipated that the two nights will occur consecutively. | Assessed on the night of the social rejection task and the night of the control task; it is anticipated that these nights will take place consecutively | 
| Change in nocturnal pre-ejection period | Pre-ejection period will be measured by impedance cardiography, beginning at lights out and collected across the night following the rejection task and control task; it is anticipated that the two nights will occur consecutively. | Assessed on the night of the social rejection task and the night of the control task; it is anticipated that the two nights will occur consecutively | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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sleep, heart, stress