Trial Outcomes & Findings for Validation of WatchBP Office Ankle-brachial Index (ABI) Function (NCT NCT01002989)

NCT ID: NCT01002989

Last Updated: 2012-01-23

Results Overview

The validation process consisted of two parts: (i) measurement validation, which compared Doppler and Watch BP Office ABI values and assessed their association, and (ii) clinical validation, which compared the diagnosis of peripheral artery disease (PAD) by the two methods and assessed the association of Watch BP Office and Doppler ABI values with cardiovascular risk factors.

Recruitment status

COMPLETED

Target enrollment

98 participants

Primary outcome timeframe

once (cross-sectional)

Results posted on

2012-01-23

Participant Flow

Patients with various cardiovascular risk factors attending a hypertension or a diabetes outpatient clinic during the period 10/2009-06/2010 were invited to participate in the study

Participant milestones

Participant milestones
Measure
Hypertensives
Subjects assessed for hypertension underwent manual Doppler ABI measurement using a continuous wave Doppler device (Hadeco Bidop ES-100V3, Kawasaki, Japan) with a 8 MHz probe and automated ABI measurement using a validated oscillometric blood pressure monitor designed for professional use in the office (WatchBP Office device; Microlife, Widnau, Switzerland).
Overall Study
STARTED
98
Overall Study
COMPLETED
93
Overall Study
NOT COMPLETED
5

Reasons for withdrawal

Reasons for withdrawal
Measure
Hypertensives
Subjects assessed for hypertension underwent manual Doppler ABI measurement using a continuous wave Doppler device (Hadeco Bidop ES-100V3, Kawasaki, Japan) with a 8 MHz probe and automated ABI measurement using a validated oscillometric blood pressure monitor designed for professional use in the office (WatchBP Office device; Microlife, Widnau, Switzerland).
Overall Study
exclusion criteria, no consent
5

Baseline Characteristics

Validation of WatchBP Office Ankle-brachial Index (ABI) Function

Baseline characteristics by cohort

Baseline characteristics by cohort
Measure
Hypertensives
n=98 Participants
Subjects assessed for hypertension underwent manual Doppler ABI measurement using a continuous wave Doppler device (Hadeco Bidop ES-100V3, Kawasaki, Japan) with a 8 MHz probe and automated ABI measurement using a validated oscillometric blood pressure monitor designed for professional use in the office (WatchBP Office device; Microlife, Widnau, Switzerland).
Age, Categorical
<=18 years
0 Participants
n=99 Participants
Age, Categorical
Between 18 and 65 years
54 Participants
n=99 Participants
Age, Categorical
>=65 years
44 Participants
n=99 Participants
Age Continuous
62.5 years
STANDARD_DEVIATION 11.1 • n=99 Participants
Sex: Female, Male
Female
37 Participants
n=99 Participants
Sex: Female, Male
Male
61 Participants
n=99 Participants
Region of Enrollment
Greece
98 participants
n=99 Participants
Mean Doppler ABI
1.08 ratio
STANDARD_DEVIATION 0.17 • n=99 Participants
Watch BP Office minus Doppler Ankle-Brachial Index (ABI) difference
0.03 ratio
STANDARD_DEVIATION 0.11 • n=99 Participants
Mean Watch BP Office ABI
1.11 ratio
STANDARD_DEVIATION 0.17 • n=99 Participants

PRIMARY outcome

Timeframe: once (cross-sectional)

Population: Patients with various cardiovascular risk factors attending a hypertension or a diabetes outpatient clinic were invited to participate in the study. Subjects with atrial fibrillation or incompressible ankle arteries (ABI ≥1.4) were excluded.

The validation process consisted of two parts: (i) measurement validation, which compared Doppler and Watch BP Office ABI values and assessed their association, and (ii) clinical validation, which compared the diagnosis of peripheral artery disease (PAD) by the two methods and assessed the association of Watch BP Office and Doppler ABI values with cardiovascular risk factors.

Outcome measures

Outcome measures
Measure
Hypertensives
n=93 Participants
Subjects assessed for hypertension underwent manual Doppler ABI measurement using a continuous wave Doppler device (Hadeco Bidop ES-100V3, Kawasaki, Japan) with a 8 MHz probe and automated ABI measurement using a validated oscillometric blood pressure monitor designed for professional use in the office (WatchBP Office device; Microlife, Widnau, Switzerland).
Watch BP Office Minus Doppler Ankle-Brachial Index Difference
0.03 ratio
Standard Deviation 0.11

PRIMARY outcome

Timeframe: once (cross-sectional)

Outcome measures

Outcome measures
Measure
Hypertensives
n=93 Participants
Subjects assessed for hypertension underwent manual Doppler ABI measurement using a continuous wave Doppler device (Hadeco Bidop ES-100V3, Kawasaki, Japan) with a 8 MHz probe and automated ABI measurement using a validated oscillometric blood pressure monitor designed for professional use in the office (WatchBP Office device; Microlife, Widnau, Switzerland).
Mean Doppler Ankle-Brachial Index
1.08 ratio
Standard Deviation 0.17

PRIMARY outcome

Timeframe: once (cross-sectional)

Outcome measures

Outcome measures
Measure
Hypertensives
n=93 Participants
Subjects assessed for hypertension underwent manual Doppler ABI measurement using a continuous wave Doppler device (Hadeco Bidop ES-100V3, Kawasaki, Japan) with a 8 MHz probe and automated ABI measurement using a validated oscillometric blood pressure monitor designed for professional use in the office (WatchBP Office device; Microlife, Widnau, Switzerland).
Mean Watch BP Office Ankle-Brachial Index
1.11 ratio
Standard Deviation 0.17

SECONDARY outcome

Timeframe: Once (cross-sectional)

This outcome measure represents what percentage of the patients diagnosed with PAD using Doppler ABI method (reference method) were diagnosed with PAD using WatchBP Office ABI method. It also represents in what percentage of the patients in whom PAD was excluded with Doppler ABI method (reference method), PAD was excluded using WatchBP Office ABI method as well.

Outcome measures

Outcome measures
Measure
Hypertensives
n=93 Participants
Subjects assessed for hypertension underwent manual Doppler ABI measurement using a continuous wave Doppler device (Hadeco Bidop ES-100V3, Kawasaki, Japan) with a 8 MHz probe and automated ABI measurement using a validated oscillometric blood pressure monitor designed for professional use in the office (WatchBP Office device; Microlife, Widnau, Switzerland).
Agreement Between the Two Methods in Peripheral Artery Disease (PAD) Diagnosis
95 Percentage of participants

Adverse Events

Hypertensives

Serious events: 0 serious events
Other events: 0 other events
Deaths: 0 deaths

Serious adverse events

Adverse event data not reported

Other adverse events

Adverse event data not reported

Additional Information

George S. Stergiou, MD, FRCP, Associate Professor of Medicine

Hypertension Center, Third University Department of Medicine, Sotiria Hospital

Phone: +30 2107763117

Results disclosure agreements

  • Principal investigator is a sponsor employee
  • Publication restrictions are in place