Nighttime bedroom temperatures may play a significant role in heart health, especially for older individuals.
According to Dr. Fergus O’Connor from Griffith University in Queensland, excessive heat puts additional strain on the cardiovascular system. He explained that the body reacts to heat by trying to cool off, which involves circulating blood closer to the skin.
“When the heart exerts more effort for extended periods, it can lead to stress and hinder recovery from the heat experienced the previous day,” O’Connor mentioned in a statement.
Researchers sought to assess how actual bedroom temperatures impacted older adults.
The research involved 47 participants from southeast Queensland, averaging around 72 years old. Unlike many studies conducted in clinical settings, this was a “free-living” study, allowing participants to maintain their usual daily routines and sleep patterns.
The scientists tracked these individuals throughout an Australian summer, from December to March, using advanced fitness trackers to monitor heart rates during sleep hours.
Temperature sensors were also installed in participants’ bedrooms, recording data across more than 14,000 hours of sleep.
The research indicated that noticeable heart disruption began at temperatures slightly above 75 degrees Fahrenheit. Between 75 and 79 degrees, there was a 40% increase in the risk of a significant drop in heart recovery. This risk doubled at temperatures from 79 to 82 degrees, and was nearly three times greater above 82 degrees.
Dr. O’Connor suggested that keeping bedroom temperatures around 24°C (75.2°F) for those aged 65 and older could reduce stress responses during sleep.
While the study reveals a strong correlation between heat and heart stress, the observational nature means it doesn’t conclusively demonstrate heat as the sole factor. The findings might not be applicable to all demographics, as the study specifically focused on older adults in Australia. Additionally, while the wearable technology is advanced, it doesn’t match the precision of medical-grade ECGs used in hospitals.
O’Connor pointed out a lack of nighttime temperature guidelines, contrasting with existing recommendations for daytime indoor temperatures.
The study has been published in the journal BMC Medicine.
