Ankle-Brachial Index Changes Post Exercise and Its Effects on Patient-Centered Outcomes and Gait (ExerciseABI)

Exercise-Induced Ankle-Brachial Index Dynamics as a Predictive Marker in Peripheral Arterial Disease

The goal of this observational study or clinical trial is to investigate how exercise can affect different areas of a person's life, especially those people with vascular disease. This is important because exercise can be beneficial for people with vascular disease. The study could include any of the following: those aged 65 years of age and older, between the ages of 50-64 who smokes, has diabetes, high blood pressure, high cholesterol, or has a family member with vascular disease, between the ages of 18-49 with diabetes and one other factor listed above, or those with vascular disease. The main question[s] it aims to answer is if exercise testing can better predict vascular disease.

The following research questions will be addressed in this study:

1. Does baseline ABI influence the magnitude and recovery trajectory of ABI following an acute bout of exercise across a spectrum of vascular function?
2. What association does exercise-induced ABI changes have on patient-reported outcomes of quality of life and intermittent claudication?
3. Do functional outcomes of gait speed, time to claudication, gait variables related to rest breaks in 6MWT, and walking distance predict the magnitude of exercise-induced ABI reduction?

Participants will :

• complete various questionnaires and a routine screening for vascular disease *walk for 6 minutes at your own pace
• additional vascular screening tests will be performed.

Study Overview

• Status: Not yet recruiting
• Conditions: Peripheral Arterial Disease(PAD)

Detailed Description

The purpose of this study is to examine if dynamic, exercise induced changes in the ankle- brachial index (ABI) are associated with pain, quality of life, and functional outcomes to better characterize peripheral vascular disease.

Individuals will be screened for eligibility if they meet the inclusion criteria. All data collection will occur during a single laboratory visit. It is anticipated the research study will take 1-2 hours, with 1 visit total to complete the study.

The primary study endpoint is to assess the use of the ankle-brachial test after exercise. This will be accomplished when the proposed number of subjects have been enrolled and completed the proposed protocol. Secondarily, the study may be stopped due to lack of funding. The final endpoint will be the completion of all data analysis including long-term follow up data and preparation for dissemination of the research findings.

The primary safety endpoint will occur if the study participant is unable to complete any part of the protocol.

All participants will give written consent to participate in the study. Participants will be instructed to refrain from alcohol, caffeine, nicotine, and exercise for at least one hour prior to testing to minimize confounding physiological effects. Testing will occur in a temperature-controlled environment maintained between 74-78°F (23-26°C) to ensure thermal stability and vascular consistency. Participant information including age, body mass index (BMI), diabetes status, past medical history, smoking history, and a list of current medications will be collected.

Participants will be comfortably positioned supine with the head of bed flat and legs fully extended. A 10-minute rest period will precede the initial ABI test to allow for hemodynamic stabilization.

For all ABI measurements, systolic blood pressures will be measured at the brachial and dorsalis pedis or posterior tibial arteries in both lower extremities using a hand-held 8-10 MHz continuous wave Doppler ultrasound probe (Huntleigh or equivalent) and appropriately sized sphygmomanometer cuffs. See Appendix A for ABI procedure details.

The order of arterial site measurements for initial resting ABI will be determined using a computer-generated randomization schedule. The limb exhibiting the lowest resting ABI will be selected for inclusion in the statistical analysis. The ABI will be calculated as the ratio of the higher ankle systolic pressure (either dorsalis pedis or posterior tibial) to the higher brachial systolic pressure (left or right arm). All data will be recorded to the nearest 2 mmHg.

Participants will then complete a 6-minute walk test, up to max pain on the 1 to 5 Claudication Symptom Rating Scale, to elicit claudication symptoms. ABI immediately post-exercise and at 1-, 3-, and 5-minute recovery intervals will be assessed in the same position as the resting ABI.

A participant will be considered to have completed the study after participating in the single visit. No in person follow up visits are anticipated.

Demographic history and SF-36 questionnaire may be collected by phone if needed.

Participation in this study is completely voluntary, and subjects can withdraw at any time. No specimens are associated with this study. All data will be stored according to study and subject number on an LSU network server. Electronic data and analysis will be retained for a minimum of seven years after study closure, and indefinitely after that.

Standard research practices will be used to document informed consent and schedule study visits. Consented subjects will be assigned a study number. A subject log relating subject name and subject number will be maintained by study personnel on a secure computer workstation by Dr Murnane in the School of Health Professions. Original signed and dated documents for all subjects will be securely maintained in the School of Health Professions.

A research team member will contact and discuss the study with potential participants to assess his/her interest in participating. The study design outlines methods of ensuring ongoing consent. Formal consent and signing of the consent form will occur in the School of Allied Health Professions or vascular clinic at Ochsner LSU Health Shreveport with a member of the study team before any testing begins.

Subjects will have the opportunity to ask questions and decline participation in this study. A copy of the informed consent will be provided to the subject.

• Study Type: Observational
• Enrollment (Estimated): 85

Contacts and Locations

• Study Contact: Name: Sarah Murnane, PT, DPT, PhD(c); Phone Number: 318-813-2980; Email: sarah.murnane@lsuhs.edu

Study Locations

• United States
  • Louisiana
    • Shreveport, Louisiana, United States, 71130
      • LSU Health Shreveport
      • Contact: Sarah Murnane, PT, DPT, PhD(c); Phone Number: 318-813-2980; Email: sarah.murnane@lsuhs.edu
      • Principal Investigator: Sarah Murnane, PT, DPT, PhD(c)

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: Yes

• Sampling Method: Non-Probability Sample

Study Population

recruited from local outpatient rehabilitation, vascular, and internal medicine clinics

Description

Inclusion Criteria

• individuals over 65 years of age
• individuals aged 50-64 with a risk factor for atherosclerosis including diabetes mellitus, history of smoking, hyperlipidemia, hypertension, or family history of peripheral arterial disease (PAD)
• individuals aged 18-50 with diabetes mellitus and one additional risk factor for atherosclerosis as noted above, or
• individuals with known atherosclerotic disease in another vascular bed including the coronary, carotid, subclavian, renal, or mesenteric artery stenosis, and individuals with known PAD

Exclusion Criteria

• contraindications to brachial and/or ankle pressure measurement including history of deep vein thrombosis
• lymphedema of the arms or legs
• history of mastectomy or current leg ulceration preventing placement of a blood pressure cuff around the lower leg
• an inability to lie in a supine position for 15 min
• self-reported inability to walk for 6 minutes
• severe cardiac or pulmonary disease limiting exercise
• inability to obtain a Dopplerable pulse
• noncompressible arteries (ABI >1.4)
• those unable to consent

Study Plan

How is the study designed?

Number of groups / cohorts

1

Cohorts and Interventions

Group / Cohort
study participants; baseline ABI

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
magnitude of ABI reduction	Measured as both absolute and percent change, calculated as the difference between baseline ABI and ABI immediately after exercise, at 1-, 3-, and 5-minute recovery intervals.	immediately after exercise, at 1-, 3-, and 5-minute recovery intervals.

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Short-Form 36 (SF-36)	A generic outcome survey to quantify health status and health-related quality of life over 8 health domains. Minimum possible score is 0 and maximum possible score is 100. A higher score indicates better health condition, complete functioning, or absence of limitations.	prior to baseline ABI testing
International Physical Activity Questionnaire (IPAQ)	The IPAQ classifies individuals into low/moderate/high activity levels based on their subjective report of frequency, duration, and intensity of walking, moderate, and vigorous activity. Scoring for the IPAQ places individuals into a level based on their categorical score: Low Those who not meet criteria for categories 2 or 3 are considered low/inactive. Moderate Any one of the following three criteria: 3 or more days of vigorous activity of at least 20 minutes per day OR; 5 or more days of moderate-intensity activity or walking of at least 30 min per day OR; 5 or more days of any combination of walking, moderate-intensity or vigorous intensity activities achieving a minimum of at least 600 MET-min/week. High Any one of the following two criteria: Vigorous-intensity activity on at least 3 days and accumulate at least 1500 MET-min/week OR; 7 or more days of any combo of walking, moderate-intensity or vigorous intensity activities achieving a minimum of at least 3000 MET-min/week	3 times including at rest prior to 6MWT, at minute 3 and again at minute 6 during 6MWT
Gait speed	Gait speed is measured as the time taken to walk a fixed distance of 4-meters measured in meters per second (m/s) taken at a set time during the 6MWT.	gait speed between minute 0-1, minute 3-4, and minute 5-6 of 6MWT
Time to first standing rest break	The time until the participant takes their first standing rest break during the 6MWT, measured in seconds (s)	1time during 6MWT
Total duration of all standing rest breaks	The total time duration, measured in seconds, of all standing rest breaks taken by the participant during the 6MWT.	1 time during 6MWT
Number of standing rest breaks	The number of standing rest breaks taken by a participant during the 6MWT.	1 time during the 6MWT
First standing rest break	The distance to first standing rest break, measured in meters (m), during the 6MWT.	During the 6MWT
Total walking distance	The total walking distance prior to participant sitting down during the 6MWT, measured in meters (m).	1 time during the 6MWT

Collaborators and Investigators

• Sponsor: Louisiana State University Health Sciences Center Shreveport

Publications and helpful links

General Publications

• Gardner AW, Katzel LI, Sorkin JD, Bradham DD, Hochberg MC, Flinn WR, Goldberg AP. Exercise rehabilitation improves functional outcomes and peripheral circulation in patients with intermittent claudication: a randomized controlled trial. J Am Geriatr Soc. 2001 Jun;49(6):755-62. doi: 10.1046/j.1532-5415.2001.49152.x.
• McDermott MM, Tian L, Liu K, Guralnik JM, Ferrucci L, Tan J, Pearce WH, Schneider JR, Criqui MH. Prognostic value of functional performance for mortality in patients with peripheral artery disease. J Am Coll Cardiol. 2008 Apr 15;51(15):1482-9. doi: 10.1016/j.jacc.2007.12.034.
• Parmenter BJ, Dieberg G, Smart NA. Exercise training for management of peripheral arterial disease: a systematic review and meta-analysis. Sports Med. 2015 Feb;45(2):231-44. doi: 10.1007/s40279-014-0261-z.
• Gerhard-Herman MD, Gornik HL, Barrett C, Barshes NR, Corriere MA, Drachman DE, Fleisher LA, Fowkes FG, Hamburg NM, Kinlay S, Lookstein R, Misra S, Mureebe L, Olin JW, Patel RA, Regensteiner JG, Schanzer A, Shishehbor MH, Stewart KJ, Treat-Jacobson D, Walsh ME. 2016 AHA/ACC Guideline on the Management of Patients With Lower Extremity Peripheral Artery Disease: Executive Summary: A Report of the American College of Cardiology/American Heart Association Task Force on Clinical Practice Guidelines. Circulation. 2017 Mar 21;135(12):e686-e725. doi: 10.1161/CIR.0000000000000470. Epub 2016 Nov 13.
• Gerhard-Herman MD, Gornik HL, Barrett C, Barshes NR, Corriere MA, Drachman DE, Fleisher LA, Fowkes FG, Hamburg NM, Kinlay S, Lookstein R, Misra S, Mureebe L, Olin JW, Patel RA, Regensteiner JG, Schanzer A, Shishehbor MH, Stewart KJ, Treat-Jacobson D, Walsh ME. 2016 AHA/ACC Guideline on the Management of Patients With Lower Extremity Peripheral Artery Disease: A Report of the American College of Cardiology/American Heart Association Task Force on Clinical Practice Guidelines. Circulation. 2017 Mar 21;135(12):e726-e779. doi: 10.1161/CIR.0000000000000471. Epub 2016 Nov 13.

Study record dates

Study Major Dates

• Study Start (Estimated): June 1, 2026
• Primary Completion (Estimated): June 1, 2027
• Study Completion (Estimated): January 1, 2028

Study Registration Dates

• First Submitted: May 26, 2026
• First Submitted That Met QC Criteria: June 4, 2026
• First Posted (Actual): June 9, 2026

Study Record Updates

• Last Update Posted (Actual): June 9, 2026
• Last Update Submitted That Met QC Criteria: June 4, 2026
• Last Verified: May 1, 2026

More Information

Terms related to this study

• Keywords: ankle brachial index; peripheral arterial disease; doppler ultrasound
• Additional Relevant MeSH Terms: Vascular Diseases; Cardiovascular Diseases; Atherosclerosis; Arteriosclerosis; Arterial Occlusive Diseases; Peripheral Vascular Diseases; Peripheral Arterial Disease
• Other Study ID Numbers: STUDY00003226

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: UNDECIDED
• IPD Plan Description: Would need to explore institutional requirements

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No