As Wisconsin navigates repeated heat waves this summer, public health leaders in the state are worried about how more frequent and severe heat waves affect vulnerable populations
Temperatures in the 90s and high humidity first hit the state from June 29 to July 3 as part of an atmospheric heat dome that hit the Midwest and southern United States
A second high-pressure system covered much of the U.S. starting this past Saturday, leading to a heat advisory across two-thirds of the state and an extreme heat advisory for southwestern Wisconsin at the start of the week
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These extreme weather events can lead to a spike in cases at emergency rooms across the state, according to Abby Novinska-Lois, executive director of Healthy Climate Wisconsin. Her organization represents doctors, public health workers and other medical professionals who are concerned about the detrimential health impacts of climate change
“When people think about heat, they often think about heat illness or heat stroke as one of the things to look out for,” she said. “But there are other physical illnesses and conditions that are also worsened by heat.”
The human heart has to work harder when trying to cool itself down, according to Novinska-Lois, which puts people with heart disease and related illness at increased risk
Prolonged hot spells can also lead to kidney problems. Recent research by the University of Wisconsin-Madison found deaths among adults receiving regular dialysis increased by 15 to 20 percent during periods of high heat and humidity
But Novinska-Lois said it’s not just people who are in kidney failure
“Somebody who might work outside often, is sweating during the day and dehydrating, and then that happens day in and day out, and we start to see more kidney issues,” she said
Common medications to control blood pressure and antidepressants can also make people more vulnerable heat-related illness. And extreme heat can be especially dangerous to people struggling with substance abuse.
Public Health Madison and Dane County issued an alert on July 1 warning of a spike in overdoses related to the summer’s first heat dome.
Public health supervisor Julia Olsen said the department wanted to warn the community about the increased risk of overdose when using opioids during extreme heat. But she said using any substance, including stimulants or alcohol, can also increase the risk of heat-related illness
“Your body is already working harder to stay cool, and adding substances to that can affect your breathing. It can affect your heart functioning, alertness or your body’s ability to just regulate its own temperature. And that can get really overwhelming to your body very quickly,” Olsen said
She said the risk is often even higher for people who are unsheltered and don’t have a way to escape the heat
Heat-related illness and an overdose can also look similar in some cases since both can cause confusion, abnormal breathing and loss of consciousness. She said it can make it harder for people to know how to respond if they encounter someone having a health emergency
In either case, Olsen recommends quickly calling 911 and, if possible, giving the overdose-reversing drug naloxone
“Giving someone naloxone, if it’s not an overdose, is not going to harm them,” she said. “But if that is what’s happening, it could certainly save their life.”
Heat waves have already become hotter, longer-lasting and more frequent due to climate change, according to the U.S. Environmental Protection Agency. These weather events are projected to become more severe and affect more of the country
Olsen said public health departments are already thinking about how to respond to a hotter future. That includes more public education about heat risks and making rettest days
Health Climate Wisconsin advocates for policy changes to support clean energy and reduce emissions to stop climate change from worsening. But Novinska-Lois said there are also immediate responses needed in Wisconsin, such as creating heat safety standards
“Right now, we do not have heat protections in the workplace in Wisconsin,” she said. “That is something we could do right away.”
Those heat protection policies could affect farm workers and other laborers who work outdoors, but they could also include other workers such as teachers. Novinska-Lois noted many K-12 schools lack air conditioning, which can lead to missed days of school and increased risk of heat-related illness among students and staff
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