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Heat Waves and the Elderly - Cooling Modalities

Primary Purpose

Aging, Hyperthermia

Status
Recruiting
Phase
Not Applicable
Locations
United States
Study Type
Interventional
Intervention
Water Spray
Fan
Water Spray and Fan
Control
Sponsored by
University of Texas Southwestern Medical Center
About
Eligibility
Locations
Arms
Outcomes
Full info

About this trial

This is an interventional prevention trial for Aging focused on measuring aging, heat wave, cardiovascular, low-energy cooling

Eligibility Criteria

65 Years - undefined (Older Adult)All SexesAccepts Healthy Volunteers

Inclusion Criteria:

  • 65 years of age or older
  • Free of any significant underlying medical problems based upon a detailed medical history and physical exam

Exclusion Criteria:

  • Known heart disease
  • Other chronic medical conditions requiring regular medical therapy including cancer, diabetes, uncontrolled hypertension, and uncontrolled hypercholesterolemia etc;
  • Abnormality detected on routine screening suggestive of provocable ischemia or previously undetected cardiac disease or resting left bundle branch block on screening electrocardiogram.
  • Current smokers, as well as individuals who regularly smoked within the past 3 years
  • Subject with a body mass index ≥31 kg/m2
  • Pregnant individuals

Sites / Locations

  • Texas Health Presbyterian Hospital DallasRecruiting

Arms of the Study

Arm 1

Arm 2

Arm Type

Experimental

Experimental

Arm Label

Very hot and dry

Hot and humid

Arm Description

Subjects will be exposed to 3 hours in a climate chamber set to approximately 47 deg C and 15% relative humidity, which reflects a very hot and dry heat wave condition similar to the 2018 Los Angeles heat wave. Four visits will be required to complete this arm, with each visit a different cooling modality applied.

Subjects will be exposed to 3 hours in a climate chamber set to approximately 41 deg C and 40% relative humidity, which reflects hot and humid heat wave similar to the 1995 Chicago heat wave. Four visits will be required to complete this arm, with each visit a different cooling modality applied.

Outcomes

Primary Outcome Measures

Change in core body temperature
Change in core body temperature will be measured either from a temperature sensor pill or from a rectal thermometer
Change in left ventricular function
Measures of left ventricular function, such as ventricular wall motion and ventricular filling, will be obtained from echocardiography images.

Secondary Outcome Measures

Heart rate
Heart rate will be measured from ECG electrodes attached to the participant
Cardiac output
Cardiac output (how much blood is ejected from the heart) will be measured using 3D echocardiography.
Arterial blood pressure
Arterial blood pressure will be measured using a standard arm blood pressure cuff.
Whole body sweat rate
Whole body sweat rate will be measured by through nude weight of the participant.
Markers of renal function and injury - Cystatin C
Markers of renal function and injury (e.g., cystatin C) will be evaluated from blood sampling collection.
Markers of renal function and injury - Creatinine Clearance
Markers of renal function and injury (e.g., creatinine clearance) will be evaluated from blood sampling and urine collection.
Markers of renal function and injury - Insulin-like growth factor-binding protein 7
Markers of renal function and injury (e.g., Insulin-like growth factor-binding protein 7) will be evaluated from urine sampling.
Markers of renal function and injury - Tissue inhibitor of metalloproteinases 2
Markers of renal function and injury (e.g., Tissue inhibitor of metalloproteinases 2) will be evaluated from urine sampling.
Cerebral perfusion
Cerebral perfusion will be measured by Doppler ultrasound of the internal carotid and vertebral arteries.
High sensitive cardiac troponin
A plasma-based marker of cardiac stress (high sensitive cardiac troponin) be evaluated from blood sampling.
Skin temperature
Skin temperature will be measured from small temperature sensitive electrodes attached to the participant's skin
Forced vital capacity (FVC)
Forced vital capacity will be obtained from spirometry

Full Information

First Posted
July 27, 2022
Last Updated
June 23, 2023
Sponsor
University of Texas Southwestern Medical Center
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1. Study Identification

Unique Protocol Identification Number
NCT05484739
Brief Title
Heat Waves and the Elderly - Cooling Modalities
Official Title
Heat Waves in the Elderly: Reducing Thermal and Cardiovascular Consequences
Study Type
Interventional

2. Study Status

Record Verification Date
June 2023
Overall Recruitment Status
Recruiting
Study Start Date
February 21, 2023 (Actual)
Primary Completion Date
October 1, 2025 (Anticipated)
Study Completion Date
August 31, 2026 (Anticipated)

3. Sponsor/Collaborators

Responsible Party, by Official Title
Principal Investigator
Name of the Sponsor
University of Texas Southwestern Medical Center

4. Oversight

Studies a U.S. FDA-regulated Drug Product
No
Studies a U.S. FDA-regulated Device Product
No
Data Monitoring Committee
Yes

5. Study Description

Brief Summary
The purpose of this study is to assess how well cooling modalities work in reducing cardiovascular stress of the elderly to heat wave conditions
Detailed Description
Heat waves are lethal and cause a disproportionate number of deaths in the elderly relative to any other age group. Such deaths are primarily cardiovascular, not hyperthermia itself, in origin. The central hypothesis of this work is that cardiovascular stress during heat wave conditions in the elderly can be reduced by applying low-energy cooling modalities. Comprehensive cardiovascular and thermal responses in the elderly will be evaluated during exposure to two prolonged heat wave conditions: hot and humid (replicating the 1995 Chicago heat wave), very hot and dry (replicating the 2018 Los Angeles heat wave). With each of these heat wave conditions individuals will be exposed to the following cooling modalities: no cooling (control), water spray, fan use, and fan use plus water spray.

6. Conditions and Keywords

Primary Disease or Condition Being Studied in the Trial, or the Focus of the Study
Aging, Hyperthermia
Keywords
aging, heat wave, cardiovascular, low-energy cooling

7. Study Design

Primary Purpose
Prevention
Study Phase
Not Applicable
Interventional Study Model
Crossover Assignment
Model Description
The investigators will conduct a randomized crossover design study. Older individuals will be exposed to one of two heat wave conditions (Very hot and dry or hot and humid). For each heat wave condition the individual will receive one of the following cooling strategies, with each cooling strategy applied on a different day: A) a control trial, B) skin wetting only trial, C) fan only trial, and D) a combination of skin wetting with a fan trial. Thus, to complete the trial for a selected heat wave condition (e.g., either very hot and dry or hot and humid) four experimental visits will be required - one visit for each cooling strategy.
Masking
None (Open Label)
Allocation
Randomized
Enrollment
50 (Anticipated)

8. Arms, Groups, and Interventions

Arm Title
Very hot and dry
Arm Type
Experimental
Arm Description
Subjects will be exposed to 3 hours in a climate chamber set to approximately 47 deg C and 15% relative humidity, which reflects a very hot and dry heat wave condition similar to the 2018 Los Angeles heat wave. Four visits will be required to complete this arm, with each visit a different cooling modality applied.
Arm Title
Hot and humid
Arm Type
Experimental
Arm Description
Subjects will be exposed to 3 hours in a climate chamber set to approximately 41 deg C and 40% relative humidity, which reflects hot and humid heat wave similar to the 1995 Chicago heat wave. Four visits will be required to complete this arm, with each visit a different cooling modality applied.
Intervention Type
Other
Intervention Name(s)
Water Spray
Intervention Description
Participants will receive water spraying on their body throughout the climate chamber exposure.
Intervention Type
Other
Intervention Name(s)
Fan
Intervention Description
Participants will be exposed to a fan throughout the climate chamber exposure.
Intervention Type
Other
Intervention Name(s)
Water Spray and Fan
Intervention Description
Participants will receive both water spraying and a fan throughout the climate chamber exposure.
Intervention Type
Other
Intervention Name(s)
Control
Intervention Description
Participants will NOT receive either water spray or a fan exposure.
Primary Outcome Measure Information:
Title
Change in core body temperature
Description
Change in core body temperature will be measured either from a temperature sensor pill or from a rectal thermometer
Time Frame
Body core temperature will be obtained within 60 min before the heat wave exposure after the 3 hour heat wave exposure.
Title
Change in left ventricular function
Description
Measures of left ventricular function, such as ventricular wall motion and ventricular filling, will be obtained from echocardiography images.
Time Frame
Within 60 minutes before each simulated heat wave exposure, around minute 90 of the heat wave exposure, and at the end of the 3 hour heat wave exposure
Secondary Outcome Measure Information:
Title
Heart rate
Description
Heart rate will be measured from ECG electrodes attached to the participant
Time Frame
Prior to and throughout each simulated heat wave exposure; approximately 420 minutes
Title
Cardiac output
Description
Cardiac output (how much blood is ejected from the heart) will be measured using 3D echocardiography.
Time Frame
Within 60 minutes before each simulated heat wave exposure and during each simulated heat wave exposure (up to 3 hours)
Title
Arterial blood pressure
Description
Arterial blood pressure will be measured using a standard arm blood pressure cuff.
Time Frame
Prior to and throughout each simulated heat wave exposure; an average of 480 minutes
Title
Whole body sweat rate
Description
Whole body sweat rate will be measured by through nude weight of the participant.
Time Frame
Within 60 minutes before each simulated heat wave exposure and within 30 minutes after each heat wave exposure.
Title
Markers of renal function and injury - Cystatin C
Description
Markers of renal function and injury (e.g., cystatin C) will be evaluated from blood sampling collection.
Time Frame
Within 60 minutes before each simulated heat wave exposure, during each simulated heat wave exposure (up to 3 hours), and within 2 hours after the simulated heat wave exposure
Title
Markers of renal function and injury - Creatinine Clearance
Description
Markers of renal function and injury (e.g., creatinine clearance) will be evaluated from blood sampling and urine collection.
Time Frame
Within 60 minutes before each simulated heat wave exposure, during each simulated heat wave exposure (up to 3 hours), and within 2 hours after the simulated heat wave exposure
Title
Markers of renal function and injury - Insulin-like growth factor-binding protein 7
Description
Markers of renal function and injury (e.g., Insulin-like growth factor-binding protein 7) will be evaluated from urine sampling.
Time Frame
Within 60 minutes before each simulated heat wave exposure, during each simulated heat wave exposure (up to 3 hours), and within 2 hours after the simulated heat wave exposure
Title
Markers of renal function and injury - Tissue inhibitor of metalloproteinases 2
Description
Markers of renal function and injury (e.g., Tissue inhibitor of metalloproteinases 2) will be evaluated from urine sampling.
Time Frame
Within 60 minutes before each simulated heat wave exposure, during each simulated heat wave exposure (up to 3 hours), and within 2 hours after the simulated heat wave exposure
Title
Cerebral perfusion
Description
Cerebral perfusion will be measured by Doppler ultrasound of the internal carotid and vertebral arteries.
Time Frame
Within 60 minutes before each simulated heat wave exposure and during each simulated heat wave exposure (up to 3 hours)
Title
High sensitive cardiac troponin
Description
A plasma-based marker of cardiac stress (high sensitive cardiac troponin) be evaluated from blood sampling.
Time Frame
Within 60 minutes before each simulated heat wave exposure, during each simulated heat wave exposure (up to 3 hours), and within 2 hours after the simulated heat wave exposure
Title
Skin temperature
Description
Skin temperature will be measured from small temperature sensitive electrodes attached to the participant's skin
Time Frame
Within 60 minutes before each simulated heat wave exposure and during each simulated heat wave exposure (up to 3 hours)
Title
Forced vital capacity (FVC)
Description
Forced vital capacity will be obtained from spirometry
Time Frame
Within 60 minutes before each simulated heat wave exposure and during each simulated heat wave exposure (up to 3 hours)

10. Eligibility

Sex
All
Minimum Age & Unit of Time
65 Years
Accepts Healthy Volunteers
Accepts Healthy Volunteers
Eligibility Criteria
Inclusion Criteria: 65 years of age or older Free of any significant underlying medical problems based upon a detailed medical history and physical exam Exclusion Criteria: Known heart disease Other chronic medical conditions requiring regular medical therapy including cancer, diabetes, uncontrolled hypertension, and uncontrolled hypercholesterolemia etc; Abnormality detected on routine screening suggestive of provokable ischemia or previously undetected cardiac disease or resting left bundle branch block on screening electrocardiogram. Current smokers, as well as individuals who regularly smoked within the past 3 years Subject with a body mass index ≥31 kg/m2 Pregnant individuals
Central Contact Person:
First Name & Middle Initial & Last Name or Official Title & Degree
Zachary McKenna, PhD
Phone
214-345-6557
Email
ZacharyMckenna@texashealth.org
First Name & Middle Initial & Last Name or Official Title & Degree
Bonnie Ostergren, MS
Phone
214-345-4737
Email
BonnieOrth@texashealth.org
Facility Information:
Facility Name
Texas Health Presbyterian Hospital Dallas
City
Dallas
State/Province
Texas
ZIP/Postal Code
75231
Country
United States
Individual Site Status
Recruiting
Facility Contact:
First Name & Middle Initial & Last Name & Degree
Zachary McKenna, PhD
Phone
214-345-6557
Email
ZacharyMckenna@texashealth.org
First Name & Middle Initial & Last Name & Degree
Bonnie Ostergren, MS
Phone
214.345.4737
Email
BonnieOrth@texashealth.org
First Name & Middle Initial & Last Name & Degree
Craig Crandall, PhD

12. IPD Sharing Statement

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Heat Waves and the Elderly - Cooling Modalities

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