Heat exhaustion is one of the clearest ways extreme heat can turn dangerous for people with chronic illness. Dr. Paul Biddinger said emergency departments see more heat-related illness and more worsening of chronic conditions when temperatures rise, and the risk climbs for people with heart disease and kidney disease.
“In the emergency department, when the temperature rises, we see increases in both people experiencing heat-related illness as well as people with worsening of their chronic illnesses,” he said in a previous statement cited by The Independent. He also said people at especially increased risk include those with chronic medical conditions, older adults, young children and some people living in underserved communities.
Mass General Brigham and the body
Warm weather may be welcomed, but the source says extreme heat is also one of the nation’s top killers. That warning sits alongside another basic fact: heart disease is the leading cause of death in the U.S., and kidney disease is the country’s eighth-leading cause of death.
Michael Crawford said the body tries to cool itself by sending more blood toward arteries and veins near the skin’s surface. He described those changes this way: “These important changes allow more blood to flow through arteries and veins close to your skin’s surface” and “When blood travels there, it’s able to lose a bit of warmth to the air around you.”
Lauren Siewny on heart disease
Lauren Siewny said that same cooling response can create trouble for people with clogged arteries. “You can develop a mismatch between what the heart needs when it’s working harder to face the heat and what the body is able to deliver,” she said. In practical terms, the heart has to work harder while the circulation changes that should help cool the body may not keep up.
That makes heat a problem not just for people already feeling ill, but for people whose circulation is already under strain. The source says extreme heat can worsen 4 common health conditions and is part of a longer list of 9 health conditions that can become more dangerous in hot weather.
Kidney disease and dehydration
Kidney disease can also worsen during hot weather because the kidneys depend on fluids to filter waste and toxins from the blood and to keep blood vessels clear so nutrients can travel to them. When the body is dehydrated, it cannot do that as well, which can lead to permanent kidney damage and raise the risk for kidney stones.
Kidney stones are pebble-like deposits of minerals that form in the kidneys when urine has less water in it. For readers with chronic disease, the practical step is not to treat heat as a comfort problem; it is to treat rising temperatures as a health risk that can send them to emergency care faster than expected.
