In health news, approximately 1,200 Americans die annually due to extreme heat, and the American Heart Association’s journal, “Circulation,” predicts that deaths linked to extreme heat and heart disease will more than double over the next 20 years. Scott Brocato spoke with Dr. Kristopher Crawford, the E.R. Medical Director for MountainView Regional Medical Center, about why heat and heart problems are so closely connected, with tips on how to stay healthy in the heat.
Scott Brocato:
Why are heat and heart problems so closely connected?
Dr. Kristopher Crawford:
Obviously, any level of physiologic stress makes the heart work harder and is more stressed. Part of that prediction also simply follows the demographic lines: we, like many nations in the world, have a meaningfully aging population. And heart disease tracks with the age of the population. So we are going to, in America, continue to have growing portions of our population suffer from heart disease because fortunately, everybody's living longer.
In America, we have very hot weather in some areas of the United States. And we have population shifts into the areas of the United States that have the hottest weather. We've seen large demographic moves to states like Florida, Georgia, Alabama and Mississippi; Texas, New Mexico and Arizona, which are the sunbelt. But that makes for exposure to dramatically higher temperatures than you would have, say, in New York, Michigan, Wisconsin, or the Midwestern states like Indiana, Ohio, Illinois.
So you have a couple of things just driving that one statistic, which is the population is getting older; and people in general, but specifically older people, sometimes from those more moderate climates, are moving into dramatically hotter climates. So I think that's where you end up with the challenges for management of mortality risk.
Scott Brocato:
You mentioned a lot of states that have high humidity: Georgia for example, and Texas. Does humidity play a factor? Here in New Mexico, of course, the joke is always "it's a dry heat,” but does that make a difference in heat-related illnesses?
Dr. Kristopher Crawford:
Sure. I mean, the higher humidity impairs the body's ability to cool itself. So, you know, obviously one of the key ways that human beings cool our body is to sweat onto the surface of our skin, and to allow the moisture that evaporates from our skin to carry the heat away. If you're in an environment, say, South Carolina or Georgia, as you mentioned, that has very high humidity, and your body can't carry that heat away, then you increase your risk of overheating by exposure to the outside.
On the other hand, if you're in these places where the joke is, “it's a very dry heat,” as we age--and again, we're talking about mostly an aging population risk for this--you we have what we call “imperceptible loss.” So as we age, we lose more water through our skin and through our respirations. And we don't often make up for that in intakes. So if you're in one of those drier climates, as you age, you have to drink significantly more fluids to be able to take advantage of that dry heat and the evaporative cooling that your body provides for.
Scott Brocato:
What sort of symptoms of a heat-related illness should one be aware of?
Dr. Kristopher Crawford:
I mean, obviously heat related illness is in and of itself separate from heart disease. It's specifically a real challenge here where we live. And so you want to be concerned about sensations of overheating, fatigue, do not ignore the symptom of thirst. And you know, be sure that by the time you start to feel dry, you need to seek indoor air conditioning or in a car, air-conditioned relent from the heat, and significant intake of fluids.
Scott Brocato:
What are some of the things that a person can do to take an active role in managing your health as far as that goes, especially if you have a history of, say, high blood pressure, heart disease?
Dr. Kristopher Crawford:
If you're in a hot climate, try to plan your activities for either the early morning, which we're really blessed here in the desert to have some really quite cool mornings, or late in the evening after the sun has set down. Try to stay indoors and in a cool environment during the peak hours of heat for the day; and if you do have to go out in the peak hours, try to do that in short episodes where you provide some time for cooling off, whether that's indoors, if you can get there with air conditioning; or if, for example, your work is outdoors, in a shaded place that has fans and hopefully even misting fans that will provide for some external evaporative cooling.
And again, I can't emphasize enough making sure that you have adequate fluid intake. I frequently in the emergency department have to have the conversation with patients, “you're not drinking enough fluid.” And they're like, "Well, I drink however much water.” And I'm like, "But here's your laboratory tests, and your blood work and your urinalysis all say you are significantly short on your fluid intake.” So even if we feel like we're drinking enough, there's every chance that in this environment, many of us live in elevated places in Southern New Mexico, especially in a little bit in El Paso too. But if you live in an elevation, and you're living in the desert that has that dry environment, you're going to need to take in a lot more fluids than you might be used to if you're coming from someplace else. And again I say, as you age, you're going to have to take in a lot more fluids than you were used to when you were younger.
