Effects of Passive Heat Therapy on Oxygen Consumption and Cardiovascular Fitness in Adults

NCT04026126 | Completed Results

• 2 other identifiers: STUDY00142890P20GM103418-19
• Study Type: interventional
• Target: 15
• Locations: 1 country
• Sites: 1

Brief Summary

The purpose of this study is to determine if enhanced endothelial arterial distensibility observed with heat therapy translates into improved cardiorespiratory fitness. The following aims are proposed: Aim 1: to determine if chronic heat therapy results in improvements in cardiovascular function. Aim 2: To examine potential mechanism(s) of action of heat therapy in cardiovascular function.

Conditions

Heart Failure; Heart Diseases; Cardiovascular Diseases; Endothelial Dysfunction

Keywords

Heat Therapy

Outcome Measures

Primary Outcomes (9)

• Change in Blood Pressure

  Systolic and diastolic blood pressure will be monitored using the noninvasive Clearsight (Edward Lifesciences, Irvine, CA) monitor, which incorporates a disposable, single use fingertip cuff.

  Blood pressure will be assessed at baseline and 24-48 hours after the last heat therapy session (end of study, ~2.5 weeks after first study visit). As a safety measure only, blood pressure will be monitored during every heat therapy treatment.

• Change in Stroke Volume

  Stroke volume will be monitored using the noninvasive Clearsight (Edward Lifesciences, Irvine, CA) monitor incorporates a disposable, single use fingertip cuff.

  Stroke volume will be assessed at baseline and 24-48 hours after the last heat therapy session (end of study, ~2.5 weeks after first study visit).

• Change in Stroke Volume Variation

  Stroke volume variation will be monitored using the noninvasive Clearsight (Edward Lifesciences, Irvine, CA) monitor incorporates a disposable, single use fingertip cuff.

  Stroke volume variation will be assessed at baseline and 24-48 hours after the last heat therapy session (end of study, ~2.5 weeks after first study visit).

• Change in Cardiac Index

  Cardiac index will be monitored using the noninvasive Clearsight (Edward Lifesciences, Irvine, CA) monitor incorporates a disposable, single use fingertip cuff.

  Cardiac index will be assessed at baseline and 24-48 hours after the last heat therapy session (end of study, ~2.5 weeks after first study visit).

• Change in Systemic Vascular Resistance

  Systemic vascular resistance will be monitored using the noninvasive Clearsight (Edward Lifesciences, Irvine, CA) monitor incorporates a disposable, single use fingertip cuff.

  Systemic vascular resistance will be assessed at baseline and 24-48 hours after the last heat therapy session (end of study, ~2.5 weeks after first study visit).

• Change in Maximum Oxygen Consumption (VO2max)

  Maximum oxygen consumption (VO2max) will be measured using the Bruce Ramp protocol. The Bruce Ramp protocol is a standardized treadmill exercise commonly used in clinical laboratories.

  VO2max assessment will be performed at baseline and 24-48 hours after the last heat therapy session (end of study, ~2.5 weeks after first study visit).

• Change in Concentration of Heat Shock Proteins

  Serum levels of heat shock proteins (HSP72, HSP25) and the primary heat shock protein transcription factor (HSF1) will be assessed for change post heat therapy treatment.

  Blood analyses will be performed at baseline and 24-48 hours after the last heat therapy session (end of study, ~2.5 weeks after first study visit).

• Change in Concentration of Nitric Oxide

  Nitric oxide (NO) bioavailability will be assessed for change post heat therapy treatment by measuring nitric oxide and endothelial nitric oxide synthase (eNOS).

  Blood analyses will be performed at baseline and 24-48 hours after the last heat therapy session (end of study, ~2.5 weeks after first study visit).

• Change in Concentration of Pro/Anti-inflammatory Markers

  Pro/anti-inflammatory markers (IL1ra, IL-10, IL-8, IFN, and CRP) will be assessed for change post heat therapy treatment.

  Blood analyses will be performed at baseline and 24-48 hours after the last heat therapy session (end of study, ~2.5 weeks after first study visit).

Study Arms (1)

Heat Therapy Treatment

EXPERIMENTAL

This study will recruit subjects to participate in heat therapy treatment at the University of Kansas Medical Center (KUMC). After pre-screening, informed consent, and enrollment, all subjects will have baseline hemodynamic assessments as well as VO2max measurements. Subjects will complete 10 heat therapy treatments over the course of 14 days. Hemodynamics will be assessed with the use of the Clearsight© fingertip blood pressure cuff. Within 24-48 hours after the last heat therapy experience, hemodynamic assessments and VO2max will be performed. Blood samples will be collected pre- and post intervention and analyzed for levels of nitric oxide mediators, heat shock protein levels and pro-anti-inflammatory markers.

Behavioral: Heat Therapy Treatment

Interventions

Heat Therapy Treatment BEHAVIORAL

Subjects will undergo 10 hot water immersions of 40.5 degrees Celsius for approximately 45 minutes per session over 14 days. Subjects will be immersed up to the shoulder until rectal temperature reacher 38.5 degrees Celsius (approximately 15-20 minutes). Subjects will then remain in the water bath submerged at waist level to maintain between 38.5 to 39.0 degrees Celsius for another 30 minutes. Following hot water immersion, subjects will be monitored for 10 minutes, or until temperature falls below 38.5 degrees Celsius.

Heat Therapy Treatment

Eligibility Criteria

• Age: 50 Years - 75 Years
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64), Older Adult (65+)

You may not qualify if:

• Current major cardiovascular disease (i.e.: recent myocardial infarction (heart attack), stroke, angina pectoris, high grade coronary vasculopathy or atherosclerosis, severe valvular disease, cardiac dysrhythmia that requires treatment.
• Current treatment with steroids or immunosuppressive agents
• Cancer
• Serious liver disease
• End-stage renal disease
• Judgement by medical provider that heat therapy poses an undue burden or risk
• Women who are pregnant or plan to become pregnant

Sponsors & Collaborators

• University of Kansas Medical Center: lead
• National Institute of General Medical Sciences (NIGMS): collaborator

Study Sites (1)

University of Kansas Medical Center

Kansas City, Kansas, 66160, United States

Location

MeSH Terms

Conditions

Heart Failure; Heart Diseases; Cardiovascular Diseases; Hyperthermia

Condition Hierarchy (Ancestors)

Body Temperature Changes; Signs and Symptoms; Pathological Conditions, Signs and Symptoms; Heat Stress Disorders; Wounds and Injuries

Results Point of Contact

• Title: Paige Geiger, PhD
• Organization: University of Kansas Medical Center

pgeiger@kumc.edu

913-588-7408

Study Officials

• Paige C Geiger, Ph.D.

  University of Kansas Medical Center

  PRINCIPAL INVESTIGATOR

• Brigid Flynn, MD

  University of Kansas Medical Center

  PRINCIPAL INVESTIGATOR

Publication Agreements

• PI is Sponsor Employee: No
• Restrictive Agreement: No

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: NA
• Masking: NONE
• Purpose: TREATMENT
• Intervention Model: SINGLE GROUP
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Professor of Molecular & Integrative Physiology

Study Record Dates

• First Submitted: June 26, 2019
• First Posted: July 19, 2019
• Study Start: August 29, 2019
• Primary Completion: July 14, 2021
• Study Completion: July 14, 2021
• Last Updated: October 17, 2022
• Results First Posted: October 17, 2022

Record last verified: 2022-10

Data Sharing

• IPD Sharing: Will not share

Locations

US (1)