Cardiovascular deaths caused by extreme heat are expected to grow nationwide in the U.S. between 2036 and 2065.
That’s according to a study supported by the National Institutes of Health (NIH). Researchers, who published their work in the journal Circulation, predict that adults 65 and older, and Black adults will likely be disproportionately affected.
Currently, heat only accounts for 1% of cardiovascular deaths, the study says. But as temperatures rise and more summer days feel like 90 degrees and above, experts expect that to change.
"The health burdens from extreme heat will continue to grow within the next several decades," said study author and cardiologist Dr. Sameed A. Khatana in a press release. "Due to the unequal impact of extreme heat on different populations, this is also a matter of health equity and could exacerbate health disparities that already exist."
From 1999-2020, obesity-related cardiovascular disease deaths tripled
Black individuals, and especially Black women, had higher mortality rates than any other group in the study.
Taking projected future temperatures into account, researchers expect heat-related cardiovascular deaths to grow 2.6 times for the general population — from 1,651 to 4,320 — between 2036 and 2065.
Projections were more pronounced for older and Black adults. Heat-related cardiovascular deaths could nearly triple for older adults, from 1,340 to 3,842, during that time period. For Black adults, those deaths could more than triple from 325 to 1,512 or 2,063.
Researchers accounted for several factors in their study, from age, to underlying health conditions, to where a person lived.
Most people adapt to heat through perspiration. But those with underlying health conditions, like diabetes and heart disease, may have different responses and can be at greater risk for a heart attack or stroke.
"The number of cardiovascular events due to heat affects a small proportion of adults, but this research shows how important it is for those with underlying risks to take extra steps to avoid extreme temperatures," said Dr. Lawrence J. Fine, a senior adviser in the cardiovascular division of NIH.