Study: Extreme Temperatures Linked to Heart Disease Deaths

Facts

According to a 40-year-long study published in the American Heart Association's (AHA) journal Circulation, one in 100 heart disease deaths — including ischemic heart disease, stroke, heart failure, and arrhythmia — is linked to days with extremely hot or cold temperatures.
Conducted between 1979 and 2019 and spanning 567 cities in 27 countries, the study compared cardiovascular deaths on the hottest and coldest 2.5% of days in each city to those on days with optimal temperatures. Extreme hot days accounted for an additional 2.2 deaths per 1K while extreme cold days added 9.1 deaths.
Categorizing extreme temperatures as exceeding 86°F (30°C) and dropping below 20°F (-6.7°C) in cities like Baltimore, the study suggested that extreme temperatures lead to a respective 12% and 37% greater risk of death on hot and cold days compared to moderate climate days.
On extremely hot days, the study lead, Dr. Barrak Alahmad of Harvard University, cited the heart shifting blood from major organs to where it's cooler underneath the skin and sweating as possible reasons for death.
Co-author Dr. Haitham Khraishah of the University of Maryland Medical Center said, “While we do not know the reason [for excess deaths], this may be explained by the progressive nature of heart failure as a disease, rendering patients susceptible to temperature effects."
Researchers added that they weren't able to make global estimates due to insufficient data from South Asia, the Middle East, and Africa, though former American Heart Association president Dr. Robert Harrington said, "this study contributes important information to the ongoing societal discussions regarding the relationship between climate and human health."

Sources: Axios, Medical Dialogues, Medical News, and U.S. News.

Narratives

Narrative A, as provided by ACSH. While this study will prompt discussions around climate change, the authors are correct when saying that more research is needed. One cannot simply lay heart disease deaths at the feet of heat waves and cold snaps when so many other factors in the developed world — lifestyle choices like diet which lead to obesity and diabetes — also play a significant role. The climate isn't the common denominator of everything.
Narrative B, as provided by Study Finds. As extreme temperatures are likely to continuously increase as climate change strengthens its grip on the world, studies like this are important as we seek to mitigate the effects of such volatile weather patterns. As this is a global issue, medical professionals around the world need to account for these environmental factors when dealing with their patients. Climate change and public health are deeply linked.