Young Toe-Brachial Index Assessment (TBI)

Determining the Normal Toe-Brachial Index in Young Adults

The Toe-Brachial Index (TBI) that has been using in our laboratory is 0.6, but the average value we measured in normal individuals is about 1.0, furthermore, we can not find out the reference of TBI that is currently being used. The purpose of this study is to determine the more accurate value of TBI and Ankle-Brachial Index (ABI). In this study, all participants will be required to fill out a demographic questionnaire before the blood pressures test. All participants will have their toe, ankle and brachial systolic blood pressure measurements to obtain the TBI and ABI.

Study Overview

• Status: Unknown
• Conditions: Vascular Diseases; Diabetes Mellitus; Coronary Artery Disease,

Detailed Description

All participants will fill out a demographic questionnaire that includes:

• Race, gender, age
• Height and weight
• Perceived stress level (potentially measured using Cohen's Perceived Stress scale(PSS))
• Activity level, with description hours per week, cardio versus non-cardio, and intensity (mild, moderate, intense)
• Smoking history, alcohol consumption, caffeine intake, and drug use (recreational, medicine - over - the - counter and prescription, including birth control pills)
• Hand dominance, and leg dominance
• Past medical history - with emphasis on cardiovascular disease (hypertension, cancer, coronary heart disease, diabetes mellitus, high cholesterol, coagulopathies, previous thromboses) as well as renal, adrenal, and thyroid disorders, Raynaud's phenomenon
• Family medical history (cancer, coronary heart disease, diabetes mellitus, high cholesterol)

Participants with known existing diabetes, coronary artery disease, or a history of vascular disease will be included in the study; nevertheless, their results may be analyzed in a separate cohort for comparison against those undiagnosed with the aforementioned condition.

The TBI (Toe - Brachial Index) will be measured by the following procedure.

• The assessment time and room temperature will be recorded
• The participant should lay supine for a minimum of five minutes in a warm and comfortable room
• Select the appropriate cuff for each upper arm and each large toe and separately placed them around the arm and large toe.
• The blood pressure measurements will be performed with photo plethysmography (PPS) and chart recorder. The phototransducer is connected to the PPS, and the digit cuff is connected to an aneroid sphygmomanometer.
• The toe and ipsilateral arm systolic blood pressures will be measured up to three times for accuracy.
• The TBI will be calculated by dividing the averaged toe systolic blood pressure, by the averaged brachial systolic blood pressure.

The ABI (Ankle - Brachial Index) will be measured by the following procedure.

• The blood pressure cuff will be placed proximal to the malleoli and ultrasound gel cover the skin overlying the dorsalis pedis and posterior tibial arteries in the foot.
• The dorsalis pedis and posterior tibial arteries blood pressure will be measured by using hand-held Doppler probe.
• The ankle systolic blood pressure will be taken as the higher pressure of the 2 arteries at the ankle.
• The ABI will be calculated by dividing the ankle systolic blood pressure, by the averaged brachial systolic blood pressure.

The brachial, toe and ankle blood pressures will be measured on the opposite limbs, and the TBI and ABI will be calculated following the protocol outlined above.

• Study Type: Observational
• Enrollment (Anticipated): 100

Contacts and Locations

Study Locations

• Canada
  • British Columbia
    • Vancouver, British Columbia, Canada, V5Z 1M9
      • Recruiting
      • Vancouver General Hospital (VGH) - Gordon and Leslie Diamond Health Care Centre
      • Contact: York N Hsiang, MB FRCSC; Phone Number: 604 876 5882; Email: York.Hsiang@vch.ca
      • Contact: Whitney Quong; Phone Number: 604 809 7293; Email: wquong@alumni.ubc.ca
      • Principal Investigator: York N Hsiang, MB FRCSC

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 20 years to 35 years (Adult)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

• Sampling Method: Non-Probability Sample

Study Population

Participants will be recruited from the classes of Faculty of Medicine in the University of British Columbia

Description

Inclusion Criteria:

• All students from the University of British Columbia, Faculty of Medicine graduating class of 2017

Exclusion Criteria:

• Students who declined to participate in the study

Study Plan

How is the study designed?

Design Details

• Observational Models: Case-Only
• Time Perspectives: Cross-Sectional

Number of groups / cohorts

1

Cohorts and Interventions

Group / Cohort
Toe-Brachial and Ankle-Brachial Index; toe systolic blood pressure, ankle systolic blood pressure, brachial systolic blood pressure test

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Toe-Brachial Index	The toe and ipsilateral brachial systolic blood pressures will be measured on both side of limbs. The participant should be fully-supported, comfortable, warm with arms and legs at heart level.	Minimum 5 minutes post participant lying supine

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Ankle-Brachial Index	The ankle and ipsilateral brachial systolic blood pressures will be measured on both side of limbs. The participant should be fully-supported, comfortable, warm with arms and legs at heart level.	Minimum 5 minutes post participant lying supine

Collaborators and Investigators

• Sponsor: University of British Columbia
• Investigators: Principal Investigator: York N Hsiang, MB FRCSC, UBC, Division of Vascular Surgery and Vancouver General Hospital

Publications and helpful links

General Publications

• Quong WL, Fung AT, Yu RY, Hsiang YN. Reassessing the normal toe-brachial index in young healthy adults. J Vasc Surg. 2016 Mar;63(3):652-6. doi: 10.1016/j.jvs.2015.09.019.

Study record dates

Study Major Dates

• Study Start: February 1, 2014
• Primary Completion (Anticipated): September 1, 2014
• Study Completion (Anticipated): December 1, 2014

Study Registration Dates

• First Submitted: December 19, 2013
• First Submitted That Met QC Criteria: December 19, 2013
• First Posted (Estimate): December 25, 2013

Study Record Updates

• Last Update Posted (Estimate): July 4, 2014
• Last Update Submitted That Met QC Criteria: July 2, 2014
• Last Verified: July 1, 2014

More Information

Terms related to this study

• Keywords: Systolic blood pressure; Toe-Brachial Index; Ankle-Brachial Index
• Additional Relevant MeSH Terms: Myocardial Ischemia; Heart Diseases; Cardiovascular Diseases; Arteriosclerosis; Arterial Occlusive Diseases; Coronary Disease; Coronary Artery Disease; Vascular Diseases
• Other Study ID Numbers: H13-03144