More people, especially older and Black adults, will likely die of cardiovascular problems because of extreme heat, study says

Cardiovascular deaths due to extreme heat are projected to increase between 2036 and 2065, according to a National Institutes of Health-backed study.

Published in the American Heart Association’s journal Circulation Monday, researchers found these deaths may more than double by the middle of the century, with older and Black adults likely to be disproportionately affected.

From 2008 to 2019, extreme heat was associated with 1,651 excess cardiovascular deaths per year, according to the study, which looked at data from the contiguous 48 states between May and September. 

Using this data, researchers project that by midcentury, extreme heat will be associated with 4,320 excess deaths annually, an increase of 162% — or, if greenhouse gas emissions rise significantly, 5,491 deaths annually, a 233% increase.

“Climate change and its many manifestations will play an increasingly important role on the health of communities around the world in the coming decades,” lead study author Dr. Sameed Khatana, assistant professor of medicine at the University of Pennsylvania and a staff cardiologist at the Philadelphia Veterans Affairs Medical Center, said in a news release. “Climate change is also a health equity issue as it will impact certain individuals and populations to a disproportionate degree and may exacerbate preexisting health disparities in the U.S.”

Projections were also more pronounced for Black and elderly adults. 

Depending on whether greenhouse gas emissions are kept at a minimum, the study projects people ages 65 and older could face an increase in deaths of 2.9 to 3.5 times while non-Hispanic Black adults are projected to have a 3.8 to 4.6 times increase compared with non-Hispanic White adults. 

“Previous studies have suggested Black residents may have less access to air conditioning; less tree cover; and a higher degree of the ‘urban heat island effect’ — built-up areas having a greater increase in temperature than surrounding less-developed areas,” Khatana said. “Living conditions may also have a role in terms of social isolation, which is experienced by some older adults and has previously been linked with a higher probability of death from extreme heat.”

More research is needed to understand how approaches to cooling cities may impact the health of those populations in a warming world.