As Coloradans take to the sunny outdoors in warm months, it is important to know that people with cardiovascular disease (CVD) are at greater risk from heat. According to the Cleveland Clinic, the most vulnerable people are women in general and adults of both sexes age 80 and over. Scientists have noted that with global warming continuing to advance, the frequency of heat-induced heart attacks has risen. A similar parallel has been seen with strokes.

What actually happens physiologically to raise this risk for those with CVD? The Cleveland Clinic explains that when the mercury rises, we sweat in an effort to maintain a healthy temperature. So blood is redirected to the skin, which compromises the heart’s blood supply. We can also become dehydrated, and because 90% of our blood is water, our blood volume and blood pressure will drop. This forces the heart to pump faster and work harder. It may also increase a tendency for blood to clot.

In addition, the Clinic notes, people with CVD also are often taking a diuretic or a beta-blocker, and “both types of medicine can exaggerate the body’s response to heat.” The diuretic can worsen electrolyte and fluid loss, lowering blood pressure. But when the heart as a result attempts to pump faster, the beta-blocker counteracts that effort. All of which makes CVD and heat a dangerous combo.

Also be aware of the differing signs of heat exhaustion and the more dangerous heat stroke

Heat Exhaustion: Dizziness, excess sweating, rapid weak pulse, nausea/vomiting, cold/clammy skin, muscle cramps.

Heat Stroke: Headache/confusion, elevated body temp, NO sweating, rapid strong pulse, nausea/vomiting, red hot skin, possible loss of consciousness.

In both cases, first aid includes moving to a cooler place if possible, using cold compresses if available or other method to cool the person, drinking water, and especially for heat stroke, calling 911.  

Of course, prevention is always better. The standard advice includes:

*Limit outdoor activity in the high heat of the day;

*Stay hydrated;

*Wear a hat and sunscreen;

*Be aware of any heat-related symptoms; and

*Avoid caffeine and alcohol, which contribute to dehydration.