Cardiovascular Health, Intermittent Claudication, Peripheral Arterial Disease, Peripheral Vascular Diseases, Vascular Function
Conditions
Keywords
heat therapy, cardiovascular health, endothelial function, heat intervention
Brief summary
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.
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.
Interventions
OTHERHeat Therapy Intervention
Heat Therapy Intervention of shoulder depth submersion in a 40°C hot tub.
Sponsors
British Heart Foundation
Manchester Metropolitan University
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
NONE
Intervention model description
Randomised wait-list controlled feasibility trial
Eligibility
Sex/Gender
ALL
Age
18 Years to No maximum
Healthy volunteers
No
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
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Maximum Walking Distance | Baseline to 8 weeks to 16 weeks | Maximal walking distance a participant can walk, through a graded treadmill test. |
| Time for Onset of Claudication | Baseline to 8 weeks to 16 weeks | Amount of time able to walk pain free before reaching claudication |
| Pain Free Walking Distance | Baseline to 8 weeks to 16 weeks | Maximum distance participant can walk without pain (IC) |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| EQ-5D-5L | Baseline to 8 weeks to 16 weeks | 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). |
| Markers of Inflammation | Baseline to 8 weeks to 16 weeks | Investigators will compare blood sample measures of TNF-α, CRP, MCP-1, IL-1Ra, IL-4, IL-6, IL-8, IL-10, and eHSP70. |
| Markers of Vascular Remodelling | Baseline to 8 weeks to 16 weeks | Investigators will compare blood sample measures of HIF-1α, VEGF, endothelin-1, MMP-9, MMP-10 and nitrite. |
| Tissue Oxygenation | Baseline to 8 weeks to 16 weeks | 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. |
| VascuQoL-6 | Baseline to 8 weeks to 16 weeks | 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). |
| SF-36 | Baseline to 8 weeks to 16 weeks | 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. |
| Ankle-Brachial Pressure Index | Baseline to 8 weeks to 16 weeks | Ankle brachial pressure index (ABPI): ABPI will be determined at rest and following a treadmill test by using standardised methodologies |
| Blood Pressure | Baseline to 8 weeks to 16 weeks | Following a 10-minute period of supine rest in a quiet room, blood pressure will be measured (in duplicate) using an automated sphygmomanometer. |
| Pulse Wave Velocity and Pulse Wave Analysis | Baseline to 8 weeks to 16 weeks | 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. |
| Physical Activity Levels | 7 days prior trial, 7 days prior heat intervention, 7 days after heat intervention, 7 days post trial. | 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). |
| Vascular Ultrasound Imaging | Baseline to 8 weeks to 16 weeks | 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. |
| Flow-Mediated Dilation | Baseline to 8 weeks to 16 weeks | 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. |
Other
| Measure | Time frame | Description |
|---|---|---|
| Intervention feasibility assessed via recruitment rate | through study completion, an average of 1 year | The investigators will record the number of eligible participants, as well as the number who enrol onto the study. |
| Intervention feasibility via participant comfort | through study completion, an average of 1 year | 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. |
| Intervention acceptability via workshop interviews | through study completion, an average of 1 year | 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. |
| Intervention feasibility assessed via protocol adherence | through study completion, an average of 1 year | 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. |
Countries
United Kingdom
Outcome results
None listed