Circadian Mechanisms Underlying Non-Dipping Blood Pressure in Blacks

NCT03934255 | Completed DMC

• 1 other identifier: IRB-300003266
• Study Type: interventional
• Target: 32
• Locations: 1 country
• Sites: 1

Brief Summary

This study seeks to examine central and peripheral circadian mechanisms in Blacks with appropriately dipping systolic blood pressure (blood pressure that dips by at least 10%) compared with non-dipping systolic blood pressure (blood pressure that dips by less than 10%) using a constant routine protocol. Constant routine protocols are commonly used in the field of circadian biology to examine rhythms in biological processes while controlling the entraining effects of light, activity, and diet.

Conditions

Circadian Rhythm; Blood Pressure

Outcome Measures

Primary Outcomes (5)

• Melatonin phase

  Circadian phase of melatonin obtained from saliva

  Melatonin phase during a 30-hour constant routine protocol

• Melatonin amplitude

  Circadian amplitude of melatonin obtained from saliva

  Melatonin amplitude during a 30-hour constant routine protocol

• Core body temperature phase

  Circadian phase of core body temperature recorded and transmitted wirelessly

  Core body temperature phase during a 30-hour constant routine protocol

• Core body temperature amplitude

  Circadian amplitude of core body temperature recorded and transmitted wirelessly

  Core body temperature amplitude during a 30-hour constant routine protocol

• Buccal cell mRNA expression

  Expression of Bmal1 and Period 3 obtained from buccal cell mRNA

  Expression of Bmal1 and Period 3 during a 30-hour constant routine protocol

Secondary Outcomes (2)

• Cortisol phase

  Cortisol phase during a 30-hour constant routine protocol

• Cortisol amplitude

  Cortisol amplitude during a 30-hour constant routine protocol

Study Arms (1)

Constant Routine Protocol

EXPERIMENTAL

Participants will be kept in constant conditions for 30 hours to observe circadian physiology in the absence of light, physical activity, and meals.

Other: Constant Routine Protocol

Interventions

Constant Routine Protocol OTHER

Constant routine protocols are used in circadian research to examine underlying circadian rhythms in the absence of light, activity, and meals

Constant Routine Protocol

Eligibility Criteria

• Age: 18 Years+
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Black or African American race
• Age 18 years or older

You may not qualify if:

• Work alternating or night shifts
• Pregnant or nursing
• Current illicit drug use
• History of severe mental illness
• Medical conditions that would be contraindicated for a constant routine protocol
• Take anti-hypertensive medications or beta-blockers
• Severe obstructive sleep apnea

Sponsors & Collaborators

• University of Alabama at Birmingham: lead
• American Heart Association: collaborator

Study Sites (1)

University of Alabama at Birmingham

Birmingham, Alabama, 35294-0017, United States

Location

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: NA
• Masking: NONE
• Purpose: BASIC SCIENCE
• Intervention Model: SINGLE GROUP
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Assistant Professor

Model Details: Constant routine protocol in Blacks with dipping and non-dipping blood pressure

Study Record Dates

• First Submitted: April 19, 2019
• First Posted: May 1, 2019
• Study Start: January 1, 2020
• Primary Completion: May 1, 2023
• Study Completion: May 1, 2023
• Last Updated: June 8, 2023

Record last verified: 2023-06

Locations

US (1)