Most of us love spending time outdoors during the summer months, and even as the temperatures rise, we find ourselves at backyard barbecues and watching or even participating in outdoor sports. The summer brings with it, however, an increased risk for heat-related illnesses, illnesses that you might not realize that you carry predispositions for. Many medications and chronic illnesses, as well as age itself, can greatly increase the risk for heat exhaustion, including its deadlier version, heatstroke.
Heatstroke is defined as a rise in body temperature above 104 degrees and is a medical emergency. Untreated heatstroke can damage your brain, heart, kidneys and muscles. The damage worsens the longer treatment is delayed, and disruptions in organ function can result in death. Typically, a person will first develop heat exhaustion, and may feel nauseated, and experience flushed skin, muscle cramps, and shortness of breath. They can have an increased heart rate as their body attempts to cool them, which might cause a throbbing headache. As heat exhaustion worsens, it can result in heatstroke. The person might be confused or agitated, have slurred speech, delirium, and could even have seizures. Often, but not always, they will turn red and have very dry skin, as heatstroke is often the result of the body’s inability to cool itself with its usual sweating mechanism. However, especially when heatstroke occurs during exertion, a person can still be sweating.
There are two main types of heatstroke: exertional, which occurs during intense activity, and non-exertional, which results from being in a hot environment. Heatstroke can often occur when you visit a hotter environment than you are used to, and risk is higher in your first few days of being in that environment. Here in Arizona, our spring and early summer news is filled with reports of hikers from other regions needing rescues from our mountains due to exertional intolerance to our heat. Many people don’t realize that non-exertional heatstroke can be progressive, resulting from an inability to cool oneself properly over the course of several days leading to exhaustion and heatstroke symptoms. This type of heatstroke may not be as intense, and may even occur not outdoors in direct sunlight, but instead in warm indoor environments without cooled or flowing air.
Some risks, like hiking on a hot day or being stranded without air-conditioning during a heatwave, might seem obvious. What many people don’t realize as they age, however, is that they are at higher risk than younger folks, and more susceptible than they themselves used to be, making everyday warm environments hazardous.
In fact, age itself is perhaps the biggest risk factor for heatrelated illness. Most heat exhaustion and heatstroke occurs in children under the age of four or adults over 65. Increased risk as an adult begins around age 50. The central nervous system is responsible for signaling our cooling system. Before the age of four our central nervous system is not fully formed; after 50, it just doesn’t work as well as it did before. Children under four and adults over 65 also become dehydrated more easily, allowing for more risk for both heat exhaustion and heatstroke, and perhaps most frightening, these groups are more likely to present with heatstroke without developing the warning signs of heat exhaustion first.
Many illnesses themselves predispose people to heat-related illness. Heart and lung disease both increase risk as cooling mechanisms that require increased breathing and heart rate are compromised. Those who are overweight and those who suffer from diabetes also have a greater occurrence of heat-related illness. Anything that predisposes a person to dehydration, such as certain kidney diseases, sunburn, or fever, increases risk. Previous heatstroke or exhaustion is perhaps the biggest risk factor to have future heat issues.
Many people also don’t realize that their medications may make them more vulnerable to heat-related illnesses. Beta blockers taken for hypertension or irregular heartbeat can disrupt the ability of capillaries to dilate (which helps cool the body). Diuretics, anti-depressants, sedatives, antihistamines, seizure medications, and stimulants (such as those used for ADHD) all can increase dehydration and/or disrupt the cooling mechanism, and therefore increase the risk for heat exhaustion and heatstroke.
If you realize that your risk for heat-related illness is higher than average, be sure to take some of these precautions:
- Stay out of the heat and direct sun during the hottest hours of the day, and stay indoors, preferably in air-conditioning.
- If you go to a hotter or especially a more humid environment than you are used to, give yourself a few days to acclimate before going out in the heat.
- Be sure to drink plenty of water. The number of ounces you drink should be equal to half of the number of your body weight in pounds, i.e., if you weigh 150 pounds, drink 75 ounces of water per day). Monitor your urine, and if it darkens in color during or after heat exposure, you are not drinking enough water.
- Remember that alcohol, soda, and coffee are all diuretics, so limit your intake of these in the heat.
- If you are sweating outdoors or during an activity, consider adding electrolyte replacement drinks into your diet (look for ones with real sugar as the sweetener to continue to avoid high fructose corn syrup and sucralose).
- Consider exercising indoors, but if you insist on regular outdoor activity, weigh yourself before and after to monitor how much fluid you are losing.
If you feel you might be suffering from a heat-related illness or see someone around you who may be, in most cases seek emergency help. Heat-related illness can progress quickly, and this is a place where it is better to be safe than sorry. While you wait for emergency help, get the person to shade or air-conditioning. An ice pack or cool water, especially to vascular-rich zones such as the armpits, back of the neck, back, and groin, can be very helpful in cooling them quickly.
The summer is a great time to be outdoors, as long as you are mindful of the heat, and mindful of the risk factors that you and your loved ones have for heat-related illness. Enjoy those summer barbecues and sporting events, but stay safe while doing it.
Stay healthy & be well!
– Amy Whittington, NMD