• Posted August 26, 2024

Heat-Related Deaths Keep Rising for Americans

Reversing a prior downward trend, searing summers have caused a sharp uptick in the numbers of Americans who die from heat-related causes, new data shows.

A look at U.S. Centers for Disease Control and Prevention deaths data for 1999 through 2023 showed a slight but steady decline in such deaths until 2016.

After that point, heat-related dates began to rise sharply through 2023.

"As temperatures continue to rise because of climate change, the recent increasing trend is likely to continue," concluded a team led by Jeffrey Howard. He is an associate professor of public health at the University of Texas at San Antonio.

According to the CDC, the effects of extreme heat kill about 1,220 people each year in the United States, with the combination of high temperatures and humidity being most taxing on the body.

"Heat-related illnesses, like heat exhaustion or heat stroke, happen when the body is not able to properly cool itself," the CDC explained. "While the body normally cools itself by sweating, during extreme heat, this might not be enough. In these cases, a person's body temperature rises faster than it can cool itself down. This can cause damage to the brain and other vital organs."

The elderly and small children are most vulnerable, the agency said, as are people with mental illness or chronic diseases.

"However, even young and healthy people can be affected if they participate in strenuous physical activities during hot weather," the CDC noted.

In the new study, Howard's team tracked the rate of deaths due to heat over the past 24 years.

Between 1999 and 2015, rates fluctuated somewhat, but remained under 0.4 heat-related deaths per 100,000 people. In 2014, for example, the rate of heat-related deaths had fallen to just 0.12 people per 100,000.

But as climate change triggered hotter summers, that began to change.

From 2016 on, rates rose steadily: from 0.22 in 2016, to 0.28 in 2018, then 0.41 by 2021. And last year marked a sharp peak in heat-related deaths: 0.62 per 100,000 people, more than five times the rate observed in 2014.

"The warmest average [global] temperature recorded since 1850 occurred in 2023," the researchers noted.

They said that, "although a study using data through 2018 found a downward trend in heat-related mortality in the U.S., this study is the first to our knowledge to demonstrate a reversal of this trend from 2016 to 2023."

According to the researchers, the U.S. data are in keeping with a steady rise in rates of heat fatalities observed around the world.

Unless current trends in global warming are reversed, all societies can do is try and protect the most vulnerable, the researchers said.

"Local authorities in high-risk areas should consider investing in the expansion of access to hydration centers and public cooling centers or other buildings with air conditioning," Howards team advised.

The findings were published Aug. 26 in the Journal of the American Medical Association.

More information

Learn how to stay healthy in searing heat at the American Red Cross.

SOURCE: Journal of the American Medical Association, Aug. 26, 2024