Heat Therapy and Peripheral Artery Disease

Heat Therapy for People with Peripheral Artery Disease: a Randomised Wait-List Controlled Feasibility Trial.

The purpose of the study is to assess the efficacy of a novel 8 week heat therapy intervention in intermittent claudication compared to usual care controls. Participants will be enrolled on a wait-list control randomised trial testing physiological, mechanistic, and health related outcome measures.

Study Overview

• Status: Not yet recruiting
• Conditions: Peripheral Arterial Disease; Peripheral Vascular Diseases; Intermittent Claudication; Vascular Function; Cardiovascular Health
• Intervention / Treatment: Other: Heat Therapy Intervention

Detailed Description

70 participants with PAD will be randomised into one of two groups: either wait-list controls (usual care) or heat therapy intervention. The 8 week heat therapy intervention will consist of shoulder depth submersion in a hot tub at ~40°C for three times a week. Time for heating will be graded with aim of ~60 minutes submersion time by the end of the intervention. After 8 weeks the wait-list control group will then enrol onto the heat intervention and heat therapy participants will go back to usual care. The primary outcome measure for the study is improvement in maximum walking distance, pain free walking, and time to onset claudication. This will be measured via a graded exercise test. Secondary outcomes include Quality of life as measured by generic and vascular specific questionnaires (SF-36,VascuQoL and EQ-5D-5L), vascular health measured using ABPI, blood pressure, FMD, PWV, and markers of inflammation, oxidative stress, angiogenesis and vascular remodelling will be assessed from blood samples. All aforementioned outcome measures will be taken at baseline, 8 weeks, and 16 weeks. Physical activity behaviour (measured with an accelerometer) will be monitored 7 days prior to the beginning of the study, 7 days prior heat intervention, and 7 days after heat intervention.

• Study Type: Interventional
• Enrollment (Estimated): 70
• Phase: Not Applicable

Contacts and Locations

Study Locations

• United Kingdom
  • Manchester, United Kingdom
    • Manchester Metropolitan University
    • Contact: Amy Harwood, PhD; Phone Number: 07546370405; Email: a.harwood@mmu.ac.uk
    • Contact: William Carey, MSc; Phone Number: 07753258893; Email: 22502706@stu.mmu.ac.uk
    • Contact: William Carey, MSc

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

• • Aged > 18 years

  • ABPI < 0.9 at rest or a drop of 20mmHG after exercise testing
  • Diagnosed with IC
  • Able to walk unaided
  • English-speaking and able to follow instructions
  • No previous history of heat syncope
  • Post-Menopausal or not on hormone therapy
  • Able to provide informed consent

Exclusion Criteria:

• • Walking impairment for a reason other than PAD

  • Critical limb ischaemia/rest pain
  • Asymptomatic PAD
  • Active cancer treatment
  • Clinically diagnosed diabetes or those with peripheral neuropathy
  • Recent / frequent heat exposure (e.g., sauna or hot tubs).
  • severe aortic stenosis, unstable angina, recent MI, stroke or TIA

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: None (Open Label)

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
No Intervention: Wait-list control; Usual care 8 weeks
Active Comparator: Heat Therapy Intervention; Heat therapy intervention through water submersion in a hot tub at ~40°C.	Other: Heat Therapy Intervention; Heat Therapy Intervention of shoulder depth submersion in a 40°C hot tub.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Maximum Walking Distance	Maximal walking distance a participant can walk, through a graded treadmill test.	Baseline to 8 weeks to 16 weeks
Pain Free Walking Distance	Maximum distance participant can walk without pain (IC)	Baseline to 8 weeks to 16 weeks
Time for Onset of Claudication	Amount of time able to walk pain free before reaching claudication	Baseline to 8 weeks to 16 weeks

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
VascuQoL-6	Quality of life was assessed using the Vascular Quality of Life Questionnaire (VacQoL), a disease-specific instrument comprised of 25 items rated on a 7-point Likert scale. When scored as a mean across items, the VacQoL has a range from 1 to 7, where 1 indicates the poorest quality of life and 7 the best. Alternatively, when summed, the total score ranges from 25 (worst) to 175 (best).	Baseline to 8 weeks to 16 weeks
SF-36	The Short Form 36 Health Survey Questionnaire (SF-36) is used to indicate the health status of particular populations, to help with service planning and to measure the impact of clinical and social interventions.	Baseline to 8 weeks to 16 weeks
EQ-5D-5L	The EQ-5D-5L is a brief, multi-attribute, generic, health status measure composed of 5 questions with Likert response options (descriptive system) and a visual analogue scale. The latter asks patients to rate their own health from 0 to 100 (the worst and best imaginable health, respectively).	Baseline to 8 weeks to 16 weeks
Markers of Inflammation	Investigators will compare blood sample measures of TNF-α, CRP, MCP-1, IL-1Ra, IL-4, IL-6, IL-8, IL-10, and eHSP70.	Baseline to 8 weeks to 16 weeks
Markers of Vascular Remodelling	Investigators will compare blood sample measures of HIF-1α, VEGF, endothelin-1, MMP-9, MMP-10 and nitrite.	Baseline to 8 weeks to 16 weeks
Tissue Oxygenation	Superficial tissue oxygen saturation and muscle oxygen consumption will be measured throughout the protocol by a NIRS probe placed on the skin surface of the medial gastrocnemius on the most affected leg. Measurements will be recorded during the graded treadmill test.	Baseline to 8 weeks to 16 weeks
Vascular Ultrasound Imaging	Vascular ultrasound images of the carotid, brachial and superficial femoral artery will be obtained using a high-resolution duplex machine (Terason, Burlington, MA) and subsequently used to calculate wall thickness, changes in arterial blood flow and shear stress.	Baseline to 8 weeks to 16 weeks
Flow-Mediated Dilation	Flow-mediated dilation (FMD) of the brachial artery will be measured after 10 min of supine rest via reactive hyperemia in response to transient ischemia of the lower arm according to international guidelines.	Baseline to 8 weeks to 16 weeks
Ankle-Brachial Pressure Index	Ankle brachial pressure index (ABPI): ABPI will be determined at rest and following a treadmill test by using standardised methodologies	Baseline to 8 weeks to 16 weeks
Blood Pressure	Following a 10-minute period of supine rest in a quiet room, blood pressure will be measured (in duplicate) using an automated sphygmomanometer.	Baseline to 8 weeks to 16 weeks
Pulse Wave Velocity and Pulse Wave Analysis	Pulse wave velocity will be measured using central (carotid-femoral) and peripheral (carotid-radial) via a handheld tonometer following standard guidelines. This will be used with a SphygmoCor XCEL.	Baseline to 8 weeks to 16 weeks
Physical Activity Levels	Physical activity will be measured using a wrist-worn accelerometer. Physical activity will be monitored for 7 days at a time. This including 7 days pre-trial, 7 days pre heat intervention, 7 days post heat intervention, and 7 days post trial (Dependent on what group randomisation was first).	7 days prior trial, 7 days prior heat intervention, 7 days after heat intervention, 7 days post trial.

Other Outcome Measures

Outcome Measure	Measure Description	Time Frame
Intervention feasibility assessed via recruitment rate	The investigators will record the number of eligible participants, as well as the number who enrol onto the study.	through study completion, an average of 1 year
Intervention feasibility assessed via protocol adherence	The investigators will examine adherence on visits to the lab for the heat therapy intervention. I.e. How many sessions were completed throughout the 8 weeks.	through study completion, an average of 1 year
Intervention acceptability via workshop interviews	Workshop interviews will be held between an investigator and participants who has either completed the intervention, withdrawn or declined participation, to ask questions regarding the intervention protocol.	through study completion, an average of 1 year
Intervention feasibility via participant comfort	The investigators will examine participant thermal comfort/discomfort throughout each intervention day. This will be done through recording of time spent in tub and thermal comfort scales.	through study completion, an average of 1 year

Collaborators and Investigators

• Sponsor: Manchester Metropolitan University
• Collaborators: British Heart Foundation

Study record dates

Study Major Dates

• Study Start (Estimated): May 1, 2025
• Primary Completion (Estimated): November 20, 2027
• Study Completion (Estimated): January 1, 2028

Study Registration Dates

• First Submitted: February 4, 2025
• First Submitted That Met QC Criteria: February 10, 2025
• First Posted (Actual): March 25, 2025

Study Record Updates

• Last Update Posted (Actual): March 25, 2025
• Last Update Submitted That Met QC Criteria: February 10, 2025
• Last Verified: February 1, 2025

More Information

Terms related to this study

• Keywords: endothelial function; cardiovascular health; heat therapy; heat intervention
• Additional Relevant MeSH Terms: Cardiovascular Diseases; Atherosclerosis; Arteriosclerosis; Arterial Occlusive Diseases; Vascular Diseases; Peripheral Arterial Disease; Peripheral Vascular Diseases; Intermittent Claudication
• Other Study ID Numbers: EthOS: 71125

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No
• product manufactured in and exported from the U.S.: No