The Effects of Diet and Exercise Interventions in Peripheral Artery Disease

Study Overview
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Brief Summary
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This study is a 3-month, prospective, randomized controlled clinical trial designed to address the efficacy of the DASH dietary program combined with a home-based exercise program, quantified by a step activity monitor, to improve exercise and vascular outcome measures in patients with PAD.

Detailed Description
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This study seeks to (1) compare the changes in 6-minute walk distance (6MWD) and physical function quality of life in patients with peripheral artery disease (PAD) following a combined intervention of the dietary approaches to stop hypertension (DASH) dietary program plus a home-based exercise program, and following a home-based exercise program alone; and (2) compare the changes in microvascular function and inflammation in patients following the combined DASH diet and home-based exercise program, and the home-based exercise program alone. The investigators hypothesize that the combined DASH diet and exercise program will result in greater increases in 6MWD and in the physical function quality of life than the exercise program alone. Further, it is hypothesized that the combined DASH diet and exercise program will result in greater improvements in calf muscle oxygen saturation [StO2] following exercise, and in high-sensitivity C-reactive protein (hsCRP]) than the exercise program alone. The home-based exercise program consists of intermittent walking to moderate claudication pain in a home-based setting. The DASH dietary program consists of the dietary approaches to stop hypertension diet emphasizing foods rich in fruits, vegetables, whole grains, and low-fat dairy.

Official Title
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The Effects of Diet and Exercise Interventions in Peripheral Artery Disease

Conditions
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Claudication, Peripheral Artery Disease

Intervention / Treatment
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* Behavioral: DASH Diet plus Home-Based Exercise
* Behavioral: Home-Based Exercise


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: History of claudication, Presence of PAD, defined by meeting at least one of the following criteria (ABI at rest < 0.90, or > 20% decrease in ABI following a heel-rise exercise test in patients with a normal ABI at rest (> 0.90), or history of peripheral revascularization. Exclusion Criteria: absence of PAD, defined by meeting all of the following 3 criteria (ABI at rest > 0.90), < 20% decrease in ABI following a heel-rise exercise test, and no history of peripheral revascularization, non-compressible vessels (ABI > 1.40), rest pain due to PAD (Fontaine stage III; Rutherford Grade II), tissue loss due to PAD (Fontaine stage IV; Rutherford Grade III), use of medications indicated for the treatment of intermittent claudication (cilostazol and pentoxifylline) initiated within three months prior to investigation, peripheral revascularization within one month prior to investigation, active cancer, end stage renal disease defined as stage 5 chronic kidney disease, medical conditions that are contraindicative for exercise according to the American College of Sports Medicine, cognitive dysfunction (mini-mental state examination score < 24), and failure to complete the baseline tests within three weeks.

Ages Eligible for Study
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Minimum Age: 60 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Interventional Model Description: Prospective, randomized controlled clinical trial
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: DASH Diet plus Home-Based Exercise<br>The DASH dietary program consists of a diet emphasizing foods rich in fruits, vegetables, whole grains, and low-fat dairy, in which patients record daily servings of fruits and vegetables. The home-based exercise program consists of intermittent walking to moderate claudication pain 3 times per week for 3 months in a home-based setting. | Behavioral: DASH Diet plus Home-Based Exercise<br>* The DASH dietary program consists of a diet emphasizing foods rich in fruits, vegetables, whole grains, and low-fat dairy, in which patients record daily servings of fruits and vegetables. The home-based exercise program consists of intermittent walking to moderate claudication pain 3 times per week for 3 months in a home-based setting.<br>|
| Active Comparator: Home-Based Exercise<br>The home-based exercise program consists of intermittent walking to moderate claudication pain 3 times per week for 3 months in a home-based setting. | Behavioral: Home-Based Exercise<br>* The home-based exercise program consists of intermittent walking to moderate claudication pain 3 times per week for 3 months in a home-based setting.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Peak Walking Time | The change in the time walked on a treadmill test | 3 months | 
| Physical Function subscale of quality of life from the Medical Outcomes Study Short-Form 36 questionnaire | The change in the Physical Function subscale from the pre-test value to the post-test value | 3 months | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| calf muscle oxygen saturation | The change in the calf muscle oxygen saturation value during exercise from the pre-test value to the post-test value | 3 months | 
| 6-minute walk distance | The change in 6-minute walk distance from the pre-test value to the post-test value | 3 months | 
| high-sensitivity C-reactive protein | The change in the high-sensitivity C-reactive protein value from the pre-test value to the post-test value | 3 months |