Non-Dipping Hypertension and The Human Chronobiome

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Study Overview

Do you have high nighttime blood pressure? Are you healthy, but interested in having a blood pressure study? Penn Medicine is seeking study participants 18years of age and older to have their blood pressure, physical activity, mobility, heart health, and social behavior monitored over 24 hours on two occasions. This research study explores why some patients with high blood pressure (hypertension) do not show a dip (decrease) in their blood pressure at night.
Hypertension is a common condition that is a well-known risk factor for various conditions such as stroke, heart attack, and kidney disease. We know that our blood pressure usually decreases (dips) at night. In some patients with hypertension, that dip is absent which puts them at higher risk for heart attacks and strokes. One of the underlying reasons might be that a person’s biorhythm, their inner body clock, is disturbed. We hope that a better understanding of this will help to achieve more effective control of blood pressure with the existing prescription drugs.

Study Description

The participation of both healthy volunteers and individuals with high blood pressure is very valuable for the study. 

In the enrollment phase of this study, you will be asked to wear a 24hour ambulatory blood pressure monitor (a wearable device that measures your blood pressure every 15-to-30-minutes over 24 hours) to describe your blood pressure pattern and to identify if your blood pressure dips at night or not. After characterizing your blood pressure pattern, the 24-hour ambulatory blood pressure measurement will be repeated twice two weeks apart while wearing an actigraph activity recorder (a research-grade fitbit) and a portable heart rate monitor. You will also be asked to answer surveys and provide blood, urine, and stool samples

Participants will be compensated for the completion of their visits as follows: 
-Enrollment Phase: No compensation apart from obtaining the individual 24 hour blood pressure analysis. 
-Phase 1: Participants are compensated for each completed visit to total $220. 

The following are criteria for exclusion from this study

1)    Known history of severe psychiatric or cognitive conditions, for example mania, schizophrenia, or mental retardation.
2)    Shift work, defined as recurring work between 22:00-05:00,
3)    History of clinically significant obstructive sleep apnea;
4)    Serum creatinine > 1.5 mg/dl in men or >1.3 mg/del in women,
5)    Significant liver disease (>3x upper limit of normal),
6)    Diabetes mellitus,
7)    Transmeridian travel across ≥2 time zones in the month prior to ABP sessions,
8)   Planned transmeridian travel across more than ≥2 time zones during the planned study activities;
9)    > 2 drinks of alcohol per day;
10)  Use of illicit drugs which affect blood pressure;
11)  Use of pacemaker or implantable Cardioverter Defibrillator, (ICD);
12)  Bilateral mastectomy;
13)  Hypotension, defined as 90/60 mmHg assessed during the screening visit from ≥ 3 in-office measurements initiated after 10 minutes in seated upright position with 5 minute intervals between measurements;
14)  History of Raynaud’s phenomenon;
15)  Known allergy against natural latex rubber (contained in ABP bladder and tubing);
16) Nursing or pregnant females.

  • Study Identifier: 828944

Recruitment Status

Enrolling By Invitation

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