Sleep and Circadian Contributions to Nighttime Blood Pressure

Status

Enrolling by invitation

Phases

Unknown

Study type

Interventional

Source

ClinicalTrials.gov

Registry ID

NCT05656768

Acronym

SCN-BP

Enrollment

1427

Registered

2022-12-19

Start date

2023-06-01

Completion date

2028-12-30

Last updated

2026-01-29

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Blood Pressure, Circadian Rhythm, Hypertension, Sleep

Keywords

sleep, circadian rhythm, circadian misalignment, nocturnal hypertension, non-dipping blood pressure

Brief summary

Broadly, this study (SCN-BP) seeks to examine sleep and circadian factors that contribute to blood pressure levels at night.

Detailed description

SCN-BP is imbedded in a parent grant titled "Improving the Detection of Hypertension (IDH-MEGA)" and examines a variety of sleep (e.g., sleep duration, timing, and the presence of sleep disorder) and circadian factors in Aims 1 and 2. In Aim 3, the investigators will conduct a 30-hour constant routine protocol to directly examine endogenous circadian and blood pressure rhythms. Aims 1 and 2 are purely observation. The study design design described below pertains the intervention piece of this study (Aim 3).

Interventions

OTHERConstant Routine Protocol

A constant routine protocol is used to directly examine markers of circadian rhythmicity (e.g., melatonin and core body temperature). A constant routine protocol requires an individual to remain in a dimly lit room, in a constant semi-recumbent posture, and remain awake for more than 24 hours. It is one of two gold-standard research protocols for examining circadian rhythms in humans.

Study design

Allocation

Intervention model

SINGLE_GROUP

Primary purpose

OTHER

Masking

NONE

Eligibility

Sex/Gender

ALL

Age

18 Years to No maximum

Healthy volunteers

Yes

Inclusion criteria

* Participant in the parent grant (IDH-MEGA)

Exclusion criteria

Design outcomes

Primary

Measure	Time frame	Description
Change in Melatonin	Hourly samples obtained over 30 hours	Melatonin levels obtained from saliva samples
Change in Core body temperature	Continuous measurements over 30 hours	Core body temperature

Secondary

Measure	Time frame	Description
Change in Blood pressure	Measurements obtained every 30 minutes over 30 hours	Systolic and diastolic blood pressure obtained using an ambulatory blood pressure monitor

Countries

United States

Contacts

PRINCIPAL_INVESTIGATORStephen J Thomas, PhD

University of Alabama at Birmingham

Outcome results

None listed

Source: ClinicalTrials.gov · Data processed: Feb 4, 2026