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Sleep and Circadian Mechanisms of Non-dipping Blood Pressure

Not Applicable
Completed
Conditions
Cardiovascular Risk Factor
Hypertension
Interventions
Behavioral: Forced Desynchrony
Registration Number
NCT03558893
Lead Sponsor
Oregon Health and Science University
Brief Summary

This study will be the first to distinguish the relative contributions of sleep, circadian and behavioral mechanisms to the non-dipping BP profile in Black adults and will lay the groundwork for optimizing therapies dependent on mechanisms, such as targeting sleep, targeting circadian rhythmicity, or targeting behaviors, and raising the possibility that ideal therapy for hypertension (HTN) may differ by race. This research will ultimately help to improve health and survival in black populations with HTN.

Detailed Description

By studying standardized behaviors and regulators of BP during sleep and behavioral stresses across all circadian phases, this protocol will allow us specifically to:

1. To determine if poor sleep, while controlling for circadian phase, contributes to the higher overall BP and reduced nocturnal drop in BP in Blacks compared to Whites.

2. To determine if reduced BP responses to standardized behavioral changes across the day and night contribute to the higher overall BP and reduced nocturnal drop in BP in Blacks compared to Whites.

3. To determine if reduced circadian amplitude of BP contributes to the higher overall BP and reduced nocturnal drop in BP in Blacks compared to Whites.

Recruitment & Eligibility

Status
COMPLETED
Sex
All
Target Recruitment
30
Inclusion Criteria
  • Self-identified Black or White
  • 'normotensive' (resting systolic blood pressure (SBP) <140/90 mmHg) or uncomplicated stage 1 'hypertensive' (systolic BP between 140 and 160 mmHg or a diastolic (DBP) between 90 and 100 mmHg).
  • free of all prescription and non-prescription drugs (including caffeine, nicotine, alcohol and herbal medications)
Exclusion Criteria
  • Currently treated with pharmacologic agents for hypertension
  • Blood pressure >160/100 mmHg
  • Smoked within the last year
  • Regular night work or rotating shift work for the three months prior to the study
  • Travel across more than three time zones during the three months prior to the study.
  • Any acute, chronic or debilitating medical conditions, other than mild hypertension (140<SBP<160 or 90<DBP<100 mmHg) and severe renal disease (glomerular filtration rate <30)
  • Moderate to severe obstructive sleep apnea (OSA)
  • History of severe psychiatric illnesses or psychiatric disorders will be excluded, including alcoholism, drug dependency, major depression, manic depressive illness, schizophrenic disorders, panic disorder, generalized anxiety disorder, post-traumatic stress disorder, agoraphobia, claustrophobia, paranoid personality disorder, schizoid personality disorder, schizotypal personality disorder, borderline personality disorder, and antisocial personality disorder.

Study & Design

Study Type
INTERVENTIONAL
Study Design
SINGLE_GROUP
Arm && Interventions
GroupInterventionDescription
Forced DesynchronyForced DesynchronyAll participants will undergo a forced desynchrony protocol.
Primary Outcome Measures
NameTimeMethod
Blood pressure7-day lab stay

Blood pressure will be measured via automatic and manual-operated sphygmomanometer. Readings will be recorded in units of mmHg.

Heart rate variability7-day lab stay

Two channel ECG will be recorded for heart rate variability analysis.

Secondary Outcome Measures
NameTimeMethod
venous aldosterone7-day lab stay

venous aldosterone will be measured as an end point of renin-angiotensin and sympathetic nerve activation

venous endocannabinoids7-day lab stay

venous endocannabinoids will be measured to estimate stress habituation.

venous epinephrine7-day lab stay

Venous epinephrine will be measured for adrenal cortex contribution to sympathetic activity.

venous norepinephrine7-day lab stay

venous norepinephrine will be measured for sympathetic nerve activity's contribution to sympathetic activity.

saliva cortisol7-day lab stay

Saliva cortisol will be measured as a sympathetic potentiating hormone.

saliva melatonin7-day lab stay

saliva melatonin will be measured as a sympathetic attenuating hormone.

beat-by-beat blood pressure7-day lab stay

Beat-by-beat Blood Pressure will be measured in the fingers using a non-invasive blood pressure monitoring device.

24-hr ambulatory blood pressure2 day ambulatory period

Ambulatory blood pressure will be measured with an automatic 24-hr blood pressure monitoring device to estimate of blood pressure dipping status.

flow mediated dilation7-day lab stay

Flow mediated dilation will be measured as an indication of endothelial function.

Trial Locations

Locations (1)

Oregon Health & Science University

🇺🇸

Portland, Oregon, United States

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