Evaluating Novel Approaches for Estimating Awake and Sleep Blood Pressure

Study Overview
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Brief Summary
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The purpose of the proposed study is to test whether measuring unattended blood pressure using an automated blood pressure monitor in a clinic setting without staff being present can reduce the need for assessing out-of- clinic awake blood pressure using ambulatory monitoring. Also, the investigators will test whether asleep blood pressure can be accurately measured using a novel home blood pressure monitoring device with less burden compared with ambulatory monitoring.

Detailed Description
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For many people, blood pressure levels differ when measured in a doctor's office versus during normal daily activities. Ambulatory blood pressure monitoring, also called ABPM, involves wearing a blood pressure cuff attached to a device that is programmed to measure participants blood pressure every 30 minutes for a 24-hour period. ABPM can help better estimate a person's true average blood pressure. Although ABPM is recommended for diagnosing high blood pressure and it also measures blood pressure while people sleep, it is not available in many clinics and some people find the procedure to be uncomfortable. The purpose of this research study is to test whether blood pressure measured in a clinic setting without medical staff present is comparable to blood pressure levels measured during the daytime measured using an ABPM device. Also, the investigators will test whether asleep blood pressure can be accurately measured using a home blood pressure monitoring device. These findings may help identify new approaches for diagnosing high blood pressure without the need for ABPM. Each participant will complete four study visits. During the course of the study, participants will: Have their blood pressure measured in the clinic, six times at each of the first two study visits for a total of twelve blood pressure measurements. Complete questionnaires about their demographics, medical history, and participant sleeping habits. Have their blood drawn and provide a urine sample. Wear a Food and Drug Administration-approved ABPM device (Microlife WatchBP O3) for 24 hours. Wear a Food and Drug Administration-approved home blood pressure monitor (Microlife WatchBP Home N) while they sleep for one night. Wear an activity monitor (Actiwatch) for two 24-hour periods. The Actiwatch activity monitor measures activity levels and can be used to identify when they are asleep. Answer some questions about their experience while wearing the ABPM and home blood pressure monitor. Have an echocardiogram performed.

Official Title
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Evaluating Novel Approaches for Estimating Awake and Sleep Blood Pressure - Better BP Study

Conditions
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Blood Pressure

Intervention / Treatment
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* Other: Unattended blood pressure measurement
* Other: Attended blood pressure measurement
* Other: Ambulatory blood pressure monitoring
* Other: Home blood pressure monitoring


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Mean screening systolic blood pressure of 110 to < 160 mm Hg at most recent visit Mean screening diastolic blood pressure of 70 to <100 mm Hg at most recent visit Exclusion Criteria: Currently taking antihypertensive medications Known to be currently pregnant History of sleep apnea History of heart attack, stroke, or any cardiovascular disease History of arrhythmia (e.g. - atrial fibrillation or ventricular tachycardia) Completed ambulatory blood pressure monitoring in the past year Second shift, overnight, or jobs that will not allow ambulatory blood pressure device to measure every 30 minutes for 24 hours.

Ages Eligible for Study
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Minimum Age: 19 Years
Maximum Age: 87 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: Diagnostic
Allocation: Randomized
Intervention Model: Crossover Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Other: Unattended vs Attended Blood Pressure<br>Participants blood pressure will be measured three times attended and three times unattended. Whether investigators measure blood pressure attended first and then unattended or unattended first and then attended will be assigned using a random number generator. At visit 2, clinic blood pressure will be measured three times attended and three times unattended, as at visit 1, but in the reverse order. | Other: Unattended blood pressure measurement<br>* Participants will have their blood pressure measured three times with an automated blood pressure monitor with a technician not present in the room.<br>Other: Attended blood pressure measurement<br>* Participants will have their blood pressure measured three times with an automated blood pressure monitor with a technician present in the room.<br>|
| Other: ABPM vs HBPM<br>Participants will be fitted with either the Microlife WatchBP O3 ambulatory blood pressure monitoring device or instructed on how to use the Microlife WatchBP Home N home blood pressure device, depending on which they are assigned to complete first. The order in which participants undergo ambulatory or home blood pressure monitoring will be assigned through a random number generator. | Other: Ambulatory blood pressure monitoring<br>* Participants will have their blood pressure measured every 30 minutes over 24-hours using an ambulatory blood pressure monitor.<br>Other: Home blood pressure monitoring<br>* Participants will have their blood pressure measured three times overnight while they are asleep using a home blood pressure monitor.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Absolute difference between unattended and attended blood pressure | The difference between both systolic and diastolic blood pressure measurements when a technician is present versus when they are not present in the room. | 2 days | 
| Accuracy of measuring asleep blood pressure using a home blood pressure monitor as compared to using an ambulatory blood pressure monitor | Participants will have their systolic and diastolic blood pressure measured overnight using a home blood pressure monitor and over 24-hours using an ambulatory blood pressure monitor. | 2 days | 
| Tolerability of wearing a home blood pressure monitor versus an ambulatory blood pressure monitor: questionnaires | Participants will complete questionnaires regarding their experience wearing both the ambulatory and home blood pressure monitors as well as a questionnaire on their willingness to wear the devices again. | 3 days | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Correlation between different blood pressure measurements and LVMI | Assess the correlation between unattended versus attended clinic BP, unattended clinic BP versus awake BP on ABPM, and sleep BP on HBPM versus ABPM with left ventricular mass index (LVMI) (g/m^2). | 3 days | 
| Correlation between different blood pressure measurements and ACR | Assess the correlation between unattended versus attended clinic BP, unattended clinic BP versus awake BP on ABPM, and sleep BP on HBPM versus ABPM with albumin-to-creatinine ratio (ACR) (mg/g). | 3 days | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Ambulatory blood pressure monitoring, Home blood pressure monitoring, Clinic blood pressure, Blood pressure phenotypes