Leg Heat Therapy for Peripheral Arterial Disease

Overseen By Kimmy Marshall, RN

Age: 18+

Sex: Any

Trial Phase: Academic

Sponsor: Indiana University

Disqualifiers: Critical limb ischemia, Amputation, Cancer, others

No Placebo Group All trial participants will receive the active study treatment (no placebo)

Approved in 1 Jurisdiction This treatment is already approved in other countries

Compensation: Varies

Number of Visits: 1

Duration: 12 weeks

106 Participants Needed

Trial Summary

What is the purpose of this trial?

The goal of this randomized, double-blind, sham-controlled clinical trial is to evaluate the benefits of home-based, leg heat therapy (HT) on lower-extremity functioning and quality of life in patients who suffer from lower-extremity peripheral artery disease (PAD). We will randomize 106 patients to one of two groups that either receive leg HT or a sham intervention. The primary study outcome is the change in 6-minute walk distance between baseline and the 12-week follow up. Secondary outcomes include changes in the short physical performance battery score, handgrip strength, quality of life (measured by the Walking Impairment Questionnaire and Short-Form (SF)-36 Questionnaire), calf muscle strength (measured using a calf ergometer), size (measured by magnetic resonance imaging) and bioenergetics (assessed using phosphorus-31 magnetic resonance spectroscopy), and physical activity (measured by accelerometer).

Do I need to stop my current medications for the trial?

The trial information does not specify whether you need to stop taking your current medications. It's best to discuss this with the trial coordinators or your doctor.

What data supports the effectiveness of leg heat therapy for peripheral arterial disease?

Research shows that leg heat therapy can improve walking distance and reduce blood pressure in patients with peripheral arterial disease. It also enhances perceived physical function and lowers levels of endothelin-1, a substance that can narrow blood vessels. ^{1 2 3 4 5}

Is leg heat therapy safe for humans?

Leg heat therapy has been shown to be safe and well-tolerated in studies with patients who have peripheral artery disease. Participants adhered well to the treatment, and no significant safety concerns were reported. ^{1 2 3 5 6}

How does leg heat therapy differ from other treatments for peripheral arterial disease?

Leg heat therapy is unique because it involves using warm water to increase blood flow and reduce blood pressure, which can improve walking performance in patients with peripheral arterial disease. Unlike traditional exercise therapy, it can be done at home, is painless, and may be easier for patients to adhere to, especially those who experience pain during exercise. ^{1 2 3 4 5}

Eligibility Criteria

This trial is for men and women over 60 with lower-extremity peripheral artery disease (PAD), evidenced by a low ankle-brachial index. It's not for those with critical limb ischemia, other conditions limiting exercise tolerance, recent leg surgeries, use of walking aids besides a cane, severe kidney disease or obesity, inability to wear water-circulating trousers, certain mental impairments or thermal sensation issues in the legs.

Inclusion Criteria

My leg circulation test shows poor blood flow.

I am older than 60 years.

Exclusion Criteria

I have had a foot or leg amputation.

I have severe leg pain at rest or wounds that won't heal due to poor blood flow.

I use a walking aid that is not a cane.

Timeline

Screening

Participants are screened for eligibility to participate in the trial

2-4 weeks

Treatment

Participants receive daily leg heat therapy or sham treatment for 90 minutes over 12 weeks

12 weeks

Home-based, unsupervised

Follow-up

Participants are monitored for safety and effectiveness after treatment

12 weeks

1 visit (in-person) at week 24

Treatment Details

Interventions

• Leg Heat Therapy
• Sham Control

Trial Overview The study tests if home-based leg heat therapy improves walking ability and quality of life in PAD patients compared to a sham control. Participants are randomly assigned to either real heat treatment or fake (sham) intervention and followed up after 12 weeks to measure changes in walk distance and various health scores.

Participant Groups

Group I: Heat therapy Experimental Treatment 1 Intervention

Patients will be provided with water-circulating trousers, a water heater, and a water tank coupled to a water pump. The heater will be adjusted to warm up the water to 42ºC. Participants will be asked to apply the therapy daily for 90 min while seated or in the supine position.

Group II: Sham Control Active Control 1 Intervention

Patients will be provided with water-circulating trousers, a water heater, and a water tank coupled to a water pump. The heater will be adjusted to warm up the water to 33ºC. Participants will be asked to apply the therapy daily for 90 min while seated or in the supine position.

Who Is Running the Clinical Trial?

Indiana University

Lead Sponsor

Trials

1,063

Recruited

1,182,000+

Purdue University

Collaborator

Trials

239

Recruited

72,200+

National Institute on Aging (NIA)

Collaborator

Trials

1,841

Recruited

28,150,000+

Findings from Research

A pilot study involving 34 patients with symptomatic peripheral artery disease (PAD) found that unsupervised, home-based leg heat therapy significantly improved walking performance, with a notable increase in the 6-minute walk distance after 8 weeks compared to a sham treatment.

The leg heat therapy was shown to be safe and well-tolerated, suggesting it could be a practical and painless adjunctive treatment to enhance physical function in patients with PAD.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Effects of home-based leg heat therapy on walking performance in patients with symptomatic peripheral artery disease: a pilot randomized trial. Monroe, JC., Pae, BJ., Kargl, C., et al.[2023]

Heat therapy, involving spa bathing and calisthenics, improved walking distance and resting blood pressure in patients with peripheral arterial disease (PAD) over 12 weeks, showing excellent adherence and tolerance among participants.

Both heat therapy and traditional exercise led to similar improvements in functional ability, suggesting that heat therapy could be a viable alternative for PAD patients who struggle with conventional exercise due to pain.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Heat therapy vs. supervised exercise therapy for peripheral arterial disease: a 12-wk randomized, controlled trial. Akerman, AP., Thomas, KN., van Rij, AM., et al.[2020]

A 6-week supervised leg heat therapy (HT) using water-circulating trousers did not improve walking distance or blood pressure in patients with peripheral artery disease (PAD), but it significantly enhanced perceived physical function and reduced serum endothelin-1 levels.

The study involved 32 PAD patients, with 30 completing the treatment, showing high adherence and good tolerance to HT, indicating its potential as a supportive therapy for improving quality of life in PAD patients.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Leg heat therapy improves perceived physical function but does not enhance walking capacity or vascular function in patients with peripheral artery disease. Monroe, JC., Lin, C., Perkins, SM., et al.[2021]

In a pilot study involving 6 patients with peripheral artery disease (PAD), acute lower leg heating significantly increased blood flow in the popliteal artery, demonstrating a duration-dependent effect after treatment.

The 6-minute walk distance improved by 10% and 12% following 15 and 45 minutes of heating, respectively, indicating that even short heating sessions can enhance exercise capacity in PAD patients.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Acute Lower Leg Heating Increases Exercise Capacity in Patients With Peripheral Artery Disease. Pellinger, TK., Neighbors, CB., Simmons, GH.[2020]

In a study involving 16 patients with symptomatic peripheral artery disease (PAD), a single session of leg heat therapy (HT) significantly lowered systolic blood pressure and post-exercise levels of endothelin-1, a marker associated with vascular constriction.

While the primary outcome of peak walking time (PWT) showed a trend towards improvement after HT, indicating potential benefits for exercise performance in PAD patients, the difference was not statistically significant.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Acute effects of leg heat therapy on walking performance and cardiovascular and inflammatory responses to exercise in patients with peripheral artery disease. Monroe, JC., Song, Q., Emery, MS., et al.[2021]

Heat therapy significantly reduces mean arterial, systolic, and diastolic blood pressure, as shown in a systematic review of 15 studies involving various healthy and clinical populations.

In addition to lowering blood pressure, heat therapy improves vascular function, indicated by enhanced flow-mediated dilatation, suggesting it could be a valuable tool for preventing and managing cardiovascular disease risk factors.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

The effect of heat therapy on blood pressure and peripheral vascular function: A systematic review and meta-analysis. Pizzey, FK., Smith, EC., Ruediger, SL., et al.[2022]

References

1. United States pubmed.ncbi.nlm.nih.gov

Effects of home-based leg heat therapy on walking performance in patients with symptomatic peripheral artery disease: a pilot randomized trial. [2023]

2. United States pubmed.ncbi.nlm.nih.gov

Heat therapy vs. supervised exercise therapy for peripheral arterial disease: a 12-wk randomized, controlled trial. [2020]

3. United States pubmed.ncbi.nlm.nih.gov

Leg heat therapy improves perceived physical function but does not enhance walking capacity or vascular function in patients with peripheral artery disease. [2021]

4. United States pubmed.ncbi.nlm.nih.gov

Acute Lower Leg Heating Increases Exercise Capacity in Patients With Peripheral Artery Disease. [2020]

5. United States pubmed.ncbi.nlm.nih.gov

Acute effects of leg heat therapy on walking performance and cardiovascular and inflammatory responses to exercise in patients with peripheral artery disease. [2021]

6. England pubmed.ncbi.nlm.nih.gov

The effect of heat therapy on blood pressure and peripheral vascular function: A systematic review and meta-analysis. [2022]