Heat Waves and the Elderly With COPD

Heat Waves and the Elderly With COPD: Reducing Thermal and Cardiovascular Consequences

The purpose of this study is to investigate thermoregulatory responses in older individuals with COPD.

Study Overview

• Status: Terminated
• Conditions: Hyperthermia; Aging; COPD
• Intervention / Treatment: Other: Water Spray; Other: Control

Detailed Description

Heat waves are the leading cause of death among natural disasters in the United States.

Elderly individuals are disproportionately more likely to become ill or die during heat waves. While the elderly have a reduced ability to regulate their body temperature,8-10 hospitalizations and deaths in this population during heat waves are primarily due to cardiovascular and/or respiratory complications, not solely hyperthermia. While previous research has primarily focused on the thermal and cardiovascular consequences of healthy aging, very little research has focused on the physiological responses to heat exposure in older individuals with chronic disease, such as chronic obstructive pulmonary disease (COPD). Notably, epidemiological data suggests that pulmonary complications are a leading cause of heat wave-related hospitalizations in older adults with a diagnosis of COPD, yet nothing is known regarding the physiological mechanisms by which those with COPD are most susceptible to heat waves. To fill this important gap, the investigators will identify the physiological responses that occur in this population, relative to healthy age-matched individuals, during two unique heat wave simulations.

• Study Type: Interventional
• Enrollment (Actual): 1
• Phase: Not Applicable

Contacts and Locations

Study Locations

• United States
  • Texas
    • Dallas, Texas, United States, 75231
      • Texas Health Presbyterian Hospital Dallas

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Older Adult
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

• 65 years old or older
• Diagnosis of COPD

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
• Participant with a body mass index ≥31 kg/m2

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Other
• Allocation: Randomized
• Interventional Model: Crossover Assignment
• Masking: None (Open Label)

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Experimental: Very hot and dry; 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. Two visits will be required to complete this arm, with one visit including water spray for cooling.	Other: Water Spray; Participants will receive water spraying on their body throughout the climate chamber exposure.; Other: Control; Participants will NOT receive water spraying on their body throughout the climate exposure.
Experimental: Experimental: Hot and humid; 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. Two visits will be required to complete this arm, with one visit including water spray for cooling.	Other: Water Spray; Participants will receive water spraying on their body throughout the climate chamber exposure.; Other: Control; Participants will NOT receive water spraying on their body throughout the climate exposure.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Core body temperature	Core body temperature will be measure from gastrointestinal temperature via an ingestible telemetric pill	Prior to and throughout each simulated heat wave exposure, an average of 480 minutes
Forced expiratory volume (FEV1)	FEV1 will be assessed via spirometry	Prior to, during, and after each simulated heat wave exposure, approximately 10 min each
Forced vital capacity (FVC)	FVC will be assessed via spirometry	Prior to, during, and after each simulated heat wave exposure, approximately 10 min each
FEV1/FVC ratio	The ratio of forced expiratory volume and forced vital capacity will be assessed via spirometry	Prior to, during, and after each simulated heat wave exposure, approximately 10 min each

Collaborators and Investigators

• Sponsor: University of Texas Southwestern Medical Center
• Collaborators: American Heart Association

Study record dates

Study Major Dates

• Study Start (Actual): January 1, 2024
• Primary Completion (Actual): October 1, 2025
• Study Completion (Actual): October 1, 2025

Study Registration Dates

• First Submitted: February 26, 2024
• First Submitted That Met QC Criteria: March 4, 2024
• First Posted (Actual): March 6, 2024

Study Record Updates

• Last Update Posted (Estimated): October 24, 2025
• Last Update Submitted That Met QC Criteria: October 22, 2025
• Last Verified: October 1, 2025

More Information

Terms related to this study

• Keywords: COPD; thermoregulation; heat wave
• Additional Relevant MeSH Terms: Wounds and Injuries; Pathologic Processes; Chronic Disease; Disease Attributes; Respiratory Tract Diseases; Lung Diseases; Lung Diseases, Obstructive; Body Temperature Changes; Heat Stress Disorders; Pathological Conditions, Signs and Symptoms; Signs and Symptoms; Hyperthermia; Pulmonary Disease, Chronic Obstructive
• Other Study ID Numbers: STU_2019_1759_COPD

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: YES

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No