NCT06582680

Aging, Beta Blockers, and Thermoregulatory Responses

• Status: Recruiting
• Phase: Phase 4
• Study type: Interventional
• Enrollment: 22 (estimated)
• Sponsor: University of Texas Southwestern Medical Center · Academic / Other
• Sex: All
• Age: 65 Years
• Healthy volunteers: Accepted

Summary

This study will test the hypothesis that the drugs propranolol and metoprolol will result in greater increases in core body temperature during 3 hours of extreme heat exposure in older adults.

Detailed description

Older individuals are more likely to die or become ill during heat waves. During the 1995 Chicago heat wave, there was 35% increase in hospital admissions for individuals older than 65 years of age. Moreover, adults over the age of 65 have a heat-related death rate that is more than double any other age group. Therefore, with an increasing elderly population that is expected to rise by 60% (to 78 million) by 2035, the causes of this excess mortality must be understood to better protect the ageing United States population. It is notable that selective and non-selective beta blocker drugs are commonly prescribed to older individuals with cardiovascular diseases. In younger individuals exposed to a heat stress, beta blocker administration reduced whole-body sweat rate and skin blood flow responses resulting in greater increases in core body temperature. Notably, nothing is known regarding the effects of beta blockers on thermoregulatory responses during heat exposure in older individuals. This project will evaluate core body temperature responses to selective and non-selective beta blocker drugs during simulated heat wave exposure in older individuals.

Conditions

• Heat Stress
• Aging

Interventions

Type	Name	Description
OTHER	Ambient Heat	Subjects will spend 3-hours in a heat chamber at 41°C and 40% humidity.

Timeline

• Start date: 2024-10-04
• Primary completion: 2026-09-30
• Completion: 2026-09-30
• First posted: 2024-09-03
• Last updated: 2025-10-23

Locations

1 site across 1 country: United States

Regulatory

• FDA-regulated drug study