Extreme Heat Is Hitting Black Hearts Hardest. Here's What to Watch For.
Associate Editor Jasmine McBride reports on new research showing extreme heat poses a dramatically higher cardiovascular risk to Black adults, driven by a mix of underlying health conditions, urban heat islands and unequal access to air conditioning and tree cover. Dr. Jaya Kumar of Fairview Health Services and Dr. Sameed Ahmed Khatana explain the medical and environmental factors behind the gap, along with warning signs to watch for and how Twin Cities residents can stay safe this summer.
As temperatures climb across the country this summer, health experts are warning that the danger goes beyond discomfort. Extreme heat is putting real strain on the heart, and in the Twin Cities, that strain is falling hardest on communities of color.
Extreme heat is the leading weather-related cause of death in the United States, according to the National Weather Service. More than 2,300 people died from heat exposure nationwide in 2023, based on a report in the Journal of the American Medical Association. And research published in the American Heart Association’s journal Circulation projects that heat-related cardiovascular deaths could more than double in the coming decades.
That research also points to a stark racial gap. Non-Hispanic Black adults are projected to see a 3.8 to 4.6 times greater increase in cardiovascular deaths tied to extreme heat compared to non-Hispanic white adults, depending on how aggressively greenhouse gas policies are implemented. The increase among other racial and ethnic groups, and between men and women, was not significantly different.
Dr. Jaya Kumar, executive vice president and system chief medical officer for Fairview Health Services, said the reasons behind that gap are both medical and environmental.
“A lot of these risk factors are disproportionately prevalent in communities of color,” Kumar said, pointing to conditions like diabetes, cardiovascular disease and obesity, along with age extremes, pregnancy, poor physical condition, social isolation and lack of air conditioning. “Socioeconomic factors play a major role, like geography where they live, access to air conditioning and poor housing conditions in this population.”
Those environmental disparities are visible on the ground in the Twin Cities, where many communities of color and lower-income residents live in densely built areas with less tree cover and more industrial development. That combination intensifies what researchers call the urban heat island effect, where paved, built-up neighborhoods trap significantly more heat than surrounding areas with more green space.
Dr. Sameed Ahmed Khatana, whose research is cited in the American Heart Association’s findings, said Black residents may also have less access to air conditioning and tree cover, compounding the risk. He added that social isolation, which disproportionately affects some older adults, has previously been linked to a higher probability of death during extreme heat.
How heat strains the heart
When the body heats up, it works to cool itself by sweating, which can lead to dehydration. At the same time, the heart has to pump more blood to help regulate body temperature. Together, those changes put added stress on the cardiovascular system, a burden that can become dangerous quickly for people with existing heart conditions and even those who are otherwise healthy.
Know the warning signs
Kumar said symptoms can look different depending on age. In children and older adults, warning signs are often vague and easy to miss, such as dry skin, dry diapers or unusual fussiness. Early recognition is critical.
In adults, heat exhaustion symptoms typically include tiredness, muscle cramps, nausea, vomiting, headache and dizziness. Left unaddressed, symptoms can progress to more serious neurological effects, including irritability, confusion, seizures and, in extreme cases, coma.
Heat stroke is a medical emergency. Signs include a body temperature above 103 degrees, hot or dry skin, a rapid pulse, confusion and nausea. Anyone experiencing these symptoms should call 911 immediately.
Staying safe this summer
Health officials recommend a few basic precautions:
- Avoid outdoor activity during peak heat hours, generally between noon and 3 p.m.
- Wear lightweight, light-colored clothing, along with a hat, sunglasses and sunscreen.
- Stay hydrated with water before, during and after time outdoors, and limit alcohol and caffeine.
- Take breaks in the shade or in a cool indoor space.
Physical activity remains important for heart health even in summer. Shifting exercise to early morning or evening hours, or moving workouts indoors to air-conditioned spaces, can help reduce risk while keeping families active.
Local resources
Twin Cities residents looking for relief from the heat have several local options. The Minnesota Department of Health has published guidance on planning for and responding to extreme heat. Cooling centers have also opened across the metro area, including several operated by the Salvation Army, with additional locations listed by local news outlets covering the ongoing heat.
As summer temperatures continue to climb, health officials say awareness and early action, especially in communities already facing disproportionate risk, remain the most effective tools for protecting hearts and saving lives.
For more information, visit www.heart.org/en/affiliates/minnesota.
Jasmine McBride welcomes reader responses at jmcbride@spokesman-recorder.com.