Endothelial DysfunctionHEATNCT03618524
Effect of Local Heat Stress Via Leg Bath on Artery Function
A study testing Lower limb hot water immersion in people with Endothelial Dysfunction, run by McMaster University at 1 site in Canada.
Trial summary
Arteries are flexible in their structure and function and change in response to a variety of factors. Endothelial cells, are the skin type cells that form a layer inside arteries, and they are very important for arterial health. Read more about this study
- Who is it for?
- Ages 18 to 35 yearsHealthy volunteers can take part
- Conditions the study is for
- Endothelial Dysfunction
- What is being tested?
- Lower limb hot water immersion
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 16 participants
- Where
- 1 siteCanada
- Study dates
- 15 Jan 2019to 15 Mar 2019
- Phase
- Interventional
- Are there results?
- None posted in the registry
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 18 to 35 years
- All sexes
- Healthy volunteers accepted
- Adult
Who may be able to join
- Apparently health (i.e., no cardiovascular, musculoskeletal, or metabolic disease), 18-35 years old 18-35 years old Recreationally active (exercising 2-3 times per week)
Who cannot join
- History of cardiovascular, musculoskeletal, or metabolic disease
Trial locations and contacts
1 site in 1 country.
Canada1 site
McMaster University Vascular Dynamics Lab
Hamilton, Ontario, L8S 4L8
About this study
Arteries are flexible in their structure and function and change in response to a variety of factors. Endothelial cells, are the skin type cells that form a layer inside arteries, and they are very important for arterial health. When they work properly, they produce substances that make the artery enlarge and support a healthy environment; but when they do not work properly, they produce substances that make the artery constrict and lead to a harmful environment. We can measure the function of these cells using an ultrasound machine and a quick test. The application of heat has been shown to change the structure and function of arteries, but we need to understand how these changes happen before we can effectively use heat as a therapy. Limb heating protocols (e.g., leg bath), in contrast with whole-body heating modes (e.g., sauna), are appealing as therapies because they generally cost less and are easier to use; but evidence is needed to demonstrate that they work before widespread use can be considered. Imagine soaking your legs in a bathtub filled with warm water becoming part of the options you have for staying healthy. Clearly, there is a lot of potential for heat to be used as a therapy, particularly for people who are unable to, or have difficulty participating in other health interventions that are known to improve arterial, but we need to do this type of research before we are able to recommend warm foot baths for therapeutic purposes.
Read the detailed description
A within-subjects interventional design will be used in a cohort of 16 young, healthy males and females between the ages of 18-35 years old. Interested individuals will be invited to the lab for a screening and familiarization visit, in which the brachial artery (BA) and superficial femoral artery (SFA) will be scanned to vet for ultrasound image quality and BA and SFA flow-mediated dilation tests will be performed to ensure participant tolerance during collection visits. According to current FMD guidelines, all qualified participants will be instructed to refrain from vigorous physical activity > 24 hours, alcohol and caffeine > 8 hours, and food > 6 hours prior to each of the two experimental visits. Participants will also be asked to ingest a wireless telemetry pill 2 hours prior to each of the two experimental visits. Upon arrival, basic anthropometric measures will be collected and hematocrit will be measured in duplicate with a finger prick blood sample equivalent to two 70 µl capillary tubes. Experimental visits will begin with 10 minutes of supine rest, while the participant is instrumented with skin temperature probes on the foot, calf, thigh, chest, and arm for measurement of skin temperature; single-lead ECG (Powerlab model ML795, ADInstruments, Colorado Springs, CO, USA) and non-invasive finger cuff (Finometer MIDI, Finapres, The Netherlands) for continuous heart rate and blood pressure monitoring. Following rest, BA and SFA FMD tests will be conducted to assess baseline endothelial function. Afterwards, single-point laser Doppler flowmetry focused on the forearm will be used to track skin blood flow continuously throughout heating. The heating protocol will involve participants immersing their lower limbs either up to the ankles or the knees in a 42 °C water bath for 45 minutes, in separate conditions. The order by which participants undergo these interventions will be randomized. Five minutes after the conclusion of the intervention, BA and SFA FMD tests will be conducted to assess endothelial function in the acute phase. BA and SFA blood velocities, blood flow turbulence, endothelial shear rate, and oscillatory shear index will be assessed before and during each of the interventions; and arterial stiffness defined as carotid-femoral pulse wave velocity (PWV) and common carotid artery (CCA) distensibility will be assessed before and after each of the interventions as additional outcomes. Participants will provide written informed consent prior to beginning any portion of the study.
- Conditions
- Endothelial Dysfunction
- Being tested
- Lower limb hot water immersion
- Keywords
- heat stress, endothelial function, hot water immersion, arterial stiffness
- Medical subject headings
- Heat Stress Disorders
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Lower limb hot water immersionOther
Participants will undergo two interventions in separate visits: lower limb hot water (42 deg C) immersion up to the (1) ankles or (2) knees.
| Study group | Role | What they receive |
|---|---|---|
| Experimental | Experimental | Lower limb hot water immersion Receives: Other: Lower limb hot water immersion |
What is being measured
The primary outcome is the main question the study is designed to answer.
Flow-mediated dilation
Collected using vascular ultrasound and analyzed using semi-automated edge tracking software
Measured: Up to 2 weeks
Secondary outcomes (3)
Endothelial shear stress
Calculated using blood velocity and arterial diameter obtained from vascular ultrasound, and blood density and viscosity calculated using hematocrit
Measured: Up to 2 weeks
Pulse wave velocity
Collected using applanation tonometry and analyzed using data acquisition software
Measured: Up to 2 weeks
Arterial distensibility
Collected using ultrasound imaging and applanation tonometry, and analyzed using semi-automated edge tracking software and data acqusition software
Measured: Up to 2 weeks
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted7 Aug 2018
- Study start15 Jan 2019
- Primary completion15 Mar 2019
- Study completion15 Mar 2019
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Publications (9)Papers the sponsor has linked to this study.
- Other trials for Endothelial DysfunctionStudies of the same condition, open and under way.
- More trials run by McMaster UniversityThe sponsor's other registered studies.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase N/A
- Primary purpose
- Basic science
- Allocation
- Not applicable
- Intervention model
- Single group
- Masking
- None (open label)
- Enrolment
- 16 participants (actual)
Sponsor and investigators
- Lead sponsor
- McMaster University
- Sponsor type
- University, hospital or other
- Responsible party
- Principal investigator, Maureen MacDonald, McMaster University
- Investigators
- Maureen J MacDonald, PhD, Principal investigator, McMaster University
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT03618524
- Sponsor's protocol ID
- HEAT
- Acronym
- HEAT
- Status last verified
- Aug 2019
- First submitted
- 2 Aug 2018
- Last updated
- 13 Aug 2019
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- No
Publications
Brunt VE, Howard MJ, Francisco MA, Ely BR, Minson CT. Passive heat therapy improves endothelial function, arterial stiffness and blood pressure in sedentary humans. J Physiol. 2016 Sep 15;594(18):5329-42. doi: 10.1113/JP272453. Epub 2016 Jun 30.
PubMed 27270841Brunt VE, Eymann TM, Francisco MA, Howard MJ, Minson CT. Passive heat therapy improves cutaneous microvascular function in sedentary humans via improved nitric oxide-dependent dilation. J Appl Physiol (1985). 2016 Sep 1;121(3):716-23. doi: 10.1152/japplphysiol.00424.2016. Epub 2016 Jul 14.
PubMed 27418688Carter HH, Spence AL, Atkinson CL, Pugh CJ, Naylor LH, Green DJ. Repeated core temperature elevation induces conduit artery adaptation in humans. Eur J Appl Physiol. 2014 Apr;114(4):859-65. doi: 10.1007/s00421-013-2817-2. Epub 2014 Jan 8.
PubMed 24399113Deanfield JE, Halcox JP, Rabelink TJ. Endothelial function and dysfunction: testing and clinical relevance. Circulation. 2007 Mar 13;115(10):1285-95. doi: 10.1161/CIRCULATIONAHA.106.652859. No abstract available.
PubMed 17353456Gimbrone MA Jr, Garcia-Cardena G. Endothelial Cell Dysfunction and the Pathobiology of Atherosclerosis. Circ Res. 2016 Feb 19;118(4):620-36. doi: 10.1161/CIRCRESAHA.115.306301.
PubMed 26892962Kellogg DL Jr. In vivo mechanisms of cutaneous vasodilation and vasoconstriction in humans during thermoregulatory challenges. J Appl Physiol (1985). 2006 May;100(5):1709-18. doi: 10.1152/japplphysiol.01071.2005.
PubMed 16614368Naylor LH, Carter H, FitzSimons MG, Cable NT, Thijssen DH, Green DJ. Repeated increases in blood flow, independent of exercise, enhance conduit artery vasodilator function in humans. Am J Physiol Heart Circ Physiol. 2011 Feb;300(2):H664-9. doi: 10.1152/ajpheart.00985.2010. Epub 2010 Dec 3.
PubMed 21131471Tinken TM, Thijssen DH, Hopkins N, Black MA, Dawson EA, Minson CT, Newcomer SC, Laughlin MH, Cable NT, Green DJ. Impact of shear rate modulation on vascular function in humans. Hypertension. 2009 Aug;54(2):278-85. doi: 10.1161/HYPERTENSIONAHA.109.134361. Epub 2009 Jun 22.
PubMed 19546374Wong BJ, Hollowed CG. Current concepts of active vasodilation in human skin. Temperature (Austin). 2016 Jun 21;4(1):41-59. doi: 10.1080/23328940.2016.1200203. eCollection 2017.
PubMed 28349094
Study at a glance
From the registry record, last updated by the sponsor on 13 Aug 2019. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Effect of Local Heat Stress Via Leg Bath on Artery Function
- ClinicalTrials.gov ID
- NCT03618524
- Acronym / sponsor ID
- HEAT / HEAT
- Conditions
- Endothelial Dysfunction
- Keywords
- heat stress, endothelial function, hot water immersion, arterial stiffness
- Study type
- Interventional
- Recruitment status
- Completed
- Enrolment
- 16 participants (actual)
- Lead sponsor
- McMaster UniversityUniversity, hospital or other
- Study start
- 15 Jan 2019 (actual)
- Primary completion
- 15 Mar 2019 (actual)
- Study completion
- 15 Mar 2019 (actual)
- First posted
- 7 Aug 2018 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
Arteries are flexible in their structure and function and change in response to a variety of factors. Endothelial cells, are the skin type cells that form a layer inside arteries, and they are very important for arterial health. When they work properly, they produce substances that make the artery enlarge and support a healthy environment; but when they do not work properly, they produce substances that make the artery constrict and lead to a harmful environment. We can measure the function of these cells using an ultrasound machine and a quick test. The application of heat has been shown to change the structure and function of arteries, but we need to understand how these changes happen before we can effectively use heat as a therapy. Limb heating protocols (e.g., leg bath), in contrast with whole-body heating modes (e.g., sauna), are appealing as therapies because they generally cost less and are easier to use; but evidence is needed to demonstrate that they work before widespread use can be considered. Imagine soaking your legs in a bathtub filled with warm water becoming part of the options you have for staying healthy. Clearly, there is a lot of potential for heat to be used as a therapy, particularly for people who are unable to, or have difficulty participating in other health interventions that are known to improve arterial, but we need to do this type of research before we are able to recommend warm foot baths for therapeutic purposes.
Detailed description
A within-subjects interventional design will be used in a cohort of 16 young, healthy males and females between the ages of 18-35 years old. Interested individuals will be invited to the lab for a screening and familiarization visit, in which the brachial artery (BA) and superficial femoral artery (SFA) will be scanned to vet for ultrasound image quality and BA and SFA flow-mediated dilation tests will be performed to ensure participant tolerance during collection visits. According to current FMD guidelines, all qualified participants will be instructed to refrain from vigorous physical activity > 24 hours, alcohol and caffeine > 8 hours, and food > 6 hours prior to each of the two experimental visits. Participants will also be asked to ingest a wireless telemetry pill 2 hours prior to each of the two experimental visits. Upon arrival, basic anthropometric measures will be collected and hematocrit will be measured in duplicate with a finger prick blood sample equivalent to two 70 µl capillary tubes. Experimental visits will begin with 10 minutes of supine rest, while the participant is instrumented with skin temperature probes on the foot, calf, thigh, chest, and arm for measurement of skin temperature; single-lead ECG (Powerlab model ML795, ADInstruments, Colorado Springs, CO, USA) and non-invasive finger cuff (Finometer MIDI, Finapres, The Netherlands) for continuous heart rate and blood pressure monitoring. Following rest, BA and SFA FMD tests will be conducted to assess baseline endothelial function. Afterwards, single-point laser Doppler flowmetry focused on the forearm will be used to track skin blood flow continuously throughout heating. The heating protocol will involve participants immersing their lower limbs either up to the ankles or the knees in a 42 °C water bath for 45 minutes, in separate conditions. The order by which participants undergo these interventions will be randomized. Five minutes after the conclusion of the intervention, BA and SFA FMD tests will be conducted to assess endothelial function in the acute phase. BA and SFA blood velocities, blood flow turbulence, endothelial shear rate, and oscillatory shear index will be assessed before and during each of the interventions; and arterial stiffness defined as carotid-femoral pulse wave velocity (PWV) and common carotid artery (CCA) distensibility will be assessed before and after each of the interventions as additional outcomes. Participants will provide written informed consent prior to beginning any portion of the study.
Study design
- Primary purpose
- Basic science
- Allocation
- Not applicable
- Intervention model
- Single group
- Masking
- None (open label)
- Number of arms
- 1
| Arm | Type | Receives |
|---|---|---|
| Experimental | Experimental | Other: Lower limb hot water immersionLower limb hot water immersion |
Who may qualify
- Ages
- 18 to 35 years
- Sex
- All
- Healthy volunteers
- Accepted
- Age groups
- Adult
Key inclusion criteria (1 listed)
- Apparently health (i.e., no cardiovascular, musculoskeletal, or metabolic disease), 18-35 years old 18-35 years old Recreationally active (exercising 2-3 times per week)
Key exclusion criteria (1 listed)
- History of cardiovascular, musculoskeletal, or metabolic disease
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| Lower limb hot water immersionParticipants will undergo two interventions in separate visits: lower limb hot water (42 deg C) immersion up to the (1) ankles or (2) knees. | Other | Experimental |
Primary outcome
Flow-mediated dilation
Time frame: Up to 2 weeks
Collected using vascular ultrasound and analyzed using semi-automated edge tracking software
3 secondary outcomes
Endothelial shear stress
Time frame: Up to 2 weeks
Pulse wave velocity
Time frame: Up to 2 weeks
Arterial distensibility
Time frame: Up to 2 weeks
Results and safety
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 13 Aug 2019.
- Background: PubMed 27270841Brunt VE, Howard MJ, Francisco MA, Ely BR, Minson CT. Passive heat therapy improves endothelial function, arterial stiffness and blood pressure in sedentary humans. J Physiol. 2016 Sep 15;594(18):5329-42. doi: 10.1113/JP272453. Epub 2016 Jun 30.
- Background: PubMed 27418688Brunt VE, Eymann TM, Francisco MA, Howard MJ, Minson CT. Passive heat therapy improves cutaneous microvascular function in sedentary humans via improved nitric oxide-dependent dilation. J Appl Physiol (1985). 2016 Sep 1;121(3):716-23. doi: 10.1152/japplphysiol.00424.2016. Epub 2016 Jul 14.
- Background: PubMed 24399113Carter HH, Spence AL, Atkinson CL, Pugh CJ, Naylor LH, Green DJ. Repeated core temperature elevation induces conduit artery adaptation in humans. Eur J Appl Physiol. 2014 Apr;114(4):859-65. doi: 10.1007/s00421-013-2817-2. Epub 2014 Jan 8.
- Background: PubMed 17353456Deanfield JE, Halcox JP, Rabelink TJ. Endothelial function and dysfunction: testing and clinical relevance. Circulation. 2007 Mar 13;115(10):1285-95. doi: 10.1161/CIRCULATIONAHA.106.652859. No abstract available.
- Background: PubMed 26892962Gimbrone MA Jr, Garcia-Cardena G. Endothelial Cell Dysfunction and the Pathobiology of Atherosclerosis. Circ Res. 2016 Feb 19;118(4):620-36. doi: 10.1161/CIRCRESAHA.115.306301.
- Background: PubMed 16614368Kellogg DL Jr. In vivo mechanisms of cutaneous vasodilation and vasoconstriction in humans during thermoregulatory challenges. J Appl Physiol (1985). 2006 May;100(5):1709-18. doi: 10.1152/japplphysiol.01071.2005.
- Background: PubMed 21131471Naylor LH, Carter H, FitzSimons MG, Cable NT, Thijssen DH, Green DJ. Repeated increases in blood flow, independent of exercise, enhance conduit artery vasodilator function in humans. Am J Physiol Heart Circ Physiol. 2011 Feb;300(2):H664-9. doi: 10.1152/ajpheart.00985.2010. Epub 2010 Dec 3.
- Background: PubMed 19546374Tinken TM, Thijssen DH, Hopkins N, Black MA, Dawson EA, Minson CT, Newcomer SC, Laughlin MH, Cable NT, Green DJ. Impact of shear rate modulation on vascular function in humans. Hypertension. 2009 Aug;54(2):278-85. doi: 10.1161/HYPERTENSIONAHA.109.134361. Epub 2009 Jun 22.
- Background: PubMed 28349094Wong BJ, Hollowed CG. Current concepts of active vasodilation in human skin. Temperature (Austin). 2016 Jun 21;4(1):41-59. doi: 10.1080/23328940.2016.1200203. eCollection 2017.
- Individual participant dataSharing planned: No
Related trials for Endothelial Dysfunction
Recruiting
NightWare and Cardiovascular Health in Women With PTSD
Post Traumatic Stress Disorder, Cardiovascular Diseases
Active, not recruiting
Adipocyte-Derived Extracellular Vesicles, Weight Loss, and Endothelial Function
Obesity, Weight Loss
RecruitingObservational study
Natural History Study of Biomarkers in Pulmonary Arterial Hypertension
Pulmonary Disease, Pulmonary Hypertension
RecruitingPhase 2
Spironolactone for Pulmonary Arterial Hypertension
Pulmonary Arterial Hypertension
Not yet recruiting
Effect of Propionic Acid Supplementation on Endothelial Function
Cardiovascular Diseases, Endothelial Dysfunction
Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part. This study is not recruiting at the moment.
Maureen J MacDonald, PhD principal investigator
McMaster University
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A study testing Lower limb hot water immersion in people with Endothelial Dysfunction, run by McMaster University at 1 site in Canada.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 1 inclusion and 1 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: finished, as of the sponsor's last update on 13 Aug 2019. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 1 site in Canada. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
Are results available for this study?
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
How can a doctor refer a patient or contact the research team?
The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Flow-mediated dilation (time frame: Up to 2 weeks). It is what the study was designed to measure, not a finding.
Where can I read the original study information?
On the ClinicalTrials.gov record for NCT03618524, which also lists 9 linked publications.
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 13 Aug 2019.