Temperature Control for Heat Stress

This trial aims to determine if maintaining indoor temperatures at or below 26°C helps older adults (ages 60-85) manage heat stress during extreme heat events. It examines whether this temperature limit can prevent health issues such as increased body temperature and heart strain over three days. One group will remain in an environment at 26°C continuously, while another will experience 34°C during the day and 26°C at night. The trial seeks non-smoking older adults who can speak English or French and have conditions like controlled high blood pressure or type 2 diabetes diagnosed at least five years ago. As an unphased trial, this study provides a unique opportunity to contribute to important research on managing heat stress in older adults.

The trial protocol does not specify if you need to stop taking your current medications. However, if you or the investigators believe that your medication use or any changes in it make participation inadvisable, it may affect your eligibility.

Research has shown that keeping indoor temperatures at or below 26°C can protect older adults from dangerous increases in body heat and heart strain during very hot weather. One study found no significant rise in body temperature or heart strain when the indoor temperature was maintained at 26°C, while higher temperatures led to increased strain.

The study aims to test whether maintaining a temperature of 26°C can prevent heat-related problems over several days. Previous research suggests that this temperature is safe and comfortable for older adults. The study simulates a heatwave over a few days to observe how participants' bodies respond to controlled heat conditions.

Researchers are excited about this trial because it explores how controlling indoor temperatures during heatwaves can impact health. Unlike standard methods that rely heavily on air conditioning, this trial tests two approaches: maintaining a consistent 26°C indoors and allowing daytime overheating with cooler nights. This investigation is unique because it aims to understand the health benefits of these temperature control methods, potentially offering more sustainable ways to manage heat stress without continuous air conditioning.

This trial will compare different indoor temperature conditions during heatwaves. Research has shown that maintaining indoor temperatures at 26°C (about 79°F) or lower can reduce physical stress during heatwaves. One study found that at 26°C, body temperature and heart strain did not significantly increase. Participants in one arm of this trial will experience this condition. Another arm will expose participants to higher daytime temperatures with cooler nighttime conditions. Previous studies found that heatwaves caused higher body temperatures at night and less sleep, suggesting that cooler indoor spaces can help older adults stay safer and more comfortable during extreme heat.¹²³⁶⁷