Nighttime heat may strain aging hearts, study finds
A study of 47 older adults in Queensland, Australia found that bedroom temperatures above about 75°F during sleep increased the heart's stress and reduced recovery, with the odds of a clinically relevant drop in heart recovery rising to 40% between 75–79°F, doubling between 79–82°F, and nearly tripling above 82°F. Keeping overnight bedroom temperatures near 24°C (75.2°F) may lower stress responses in those 65 and older, though the observational design means causation cannot be established and the findings may not apply to other populations. The research used wearable devices over a southern summer and was published in BMC Medicine.