Heat Waves and the Elderly - Cooling Modalities

The University of Texas System (UT)

Status: Enrolling

Conditions: Aging; Hyperthermia

Treatments: Other: Fan; Other: Control; Other: Water Spray; Other: Water Spray and Fan

Study type: Interventional

Funder types: Other

Identifiers

NCT05484739

STU-2022-0625

Details and patient eligibility

About

The purpose of this study is to assess how well cooling modalities work in reducing cardiovascular stress of the elderly to heat wave conditions

Full 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.

Enrollment: 100 estimated patients

Sex: All

Ages: 65+ years old

Volunteers: Accepts 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 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

Trial design

Primary purpose: Prevention

Allocation: Randomized

Interventional model: Crossover Assignment

Masking: None (Open label)

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100 participants in 2 patient groups

Very hot and dry

Experimental group

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.

Treatment:

Other: Water Spray and Fan

Other: Water Spray

Other: Control

Other: Fan

Hot and humid

Experimental group

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.

Treatment:

Other: Water Spray and Fan

Other: Water Spray

Other: Control

Other: Fan