Temperatures and cardiovascular disease

James D. Lomax, MD
Posted 8/21/12

So far we have not had the usual amount of snow and cold this season, but that will no doubt change as we progress through the winter. This also is the time of the year when people seek out warm- or …

This item is available in full to subscribers.

Please log in to continue

Log in

Temperatures and cardiovascular disease

Posted

So far we have not had the usual amount of snow and cold this season, but that will no doubt change as we progress through the winter. This also is the time of the year when people seek out warm- or cold-weather locations for the winter months or for vacation. There is a relationship between ambient temperature exposure, exertion, and occurrences of cardiovascular events or other physical symptoms.

There are very specific physiological conditions that can develop when body temperature is lowered or raised excessively due to environmental exposure. Cardiovascular-type symptoms include chest pain, shortness of breath, sweating, nausea and vomiting, weakness and near to full loss of consciousness—typical of having a heart attack. For individuals with underlying congestive heart failure, symptoms can develop rapidly when they exert themselves in excessively cold or hot weather.

There are ways you can protect yourself from experiencing such symptoms when exposed to very cold or hot temperatures—see the sidebar for a partial list.

Winter and heart disease

Performing physical exertion along with prolonged exposure to freezing temperatures can significantly exert the heart, along with increasing the risk of developing hypothermia. Shoveling snow for most people will not lead to any health problems, but individuals with cardiovascular disease performing manual labor, shoveling, or just walking in snow and wind can develop symptoms suggestive of having a heart attack. Hypothermia is a condition in which the person’s body temperature falls below 95 degrees Fahrenheit (35 degrees Celsius).

Hypothermia leads to a chain of events that can cause chest pain, irregular heartbeats, confusion and potentially unconsciousness. Initial cold-weather exposure will increase blood pressure and heart rate because the heart has to work harder to circulate blood to maintain your body temperature. Some studies have shown that a drop in body temperature leads to the development of blood clots, causing heart attacks and stroke. Hypothermia requires warming of the individual and immediate emergency treatment.

Hot weather exposure and heart disease

As with cold temperatures, exposure to a hot environment can also stress the heart. Exercising or doing manual labor can lead to heat exhaustion and heat stroke. An individual with cardiovascular disease may have greater difficulty with regulating body temperature. The older adult in general (with or without heart disease) and children are at the highest risk for developing hyperthermia. Persons taking cardiac medications such as beta blockers, ACE inhibitors, calcium channel blockers and diuretics can also have an exaggerated response to heat.

Heat exhaustion includes headaches, cool, moist skin, dizziness, generalized weakness, nausea and vomiting and dark-colored urine. Signs and symptoms of a heat stroke include high body temperature (above 104 Fahrenheit or 40 Celsius), skin that is red, hot, and either moist or dry, rapid heart rate, difficulty breathing, headache, dizziness, loss of coordination, nausea and vomiting, confusion, restlessness, seizures, and unconsciousness or coma. Heat stroke is a life-threatening condition that requires immediate medical attention.

Protecting Yourself from the Elements

WINTER PREVENTION

1. Wear appropriate clothing. To keep warm, wear multiple layers of thin clothing, which helps trap body heat within the layers. Always wear a head covering, because we lose a great deal of body heat from this area. Gloves are also essential along with insulated footwear, to prevent frostbite of the fingers and toes.

2. Avoid wearing damp or sweaty clothing outside—this can lead to frostbite. Change into dry clothes as soon as possible.

3. Give yourself frequent warming breaks, especially when performing manual labor, shoveling snow, and downhill or cross-country skiing.

4. If you experience any chest pain, excessive shortness of breath, dizziness or excessive weakness, seek immediate health care.

5. Do not drink alcoholic beverages if you are going to be outside for an excessive period of time. Alcohol distorts our perception of temperature.

6. If someone in your house has known cardiovascular disease, learn CPR so that you can assist that person and others experiencing a possible heart attack.

HOT WEATHER PREVENTION

1. Dress for the heat with lightweight, light-colored clothing with a breathable fabric made from cotton or a synthetic fiber. Keep the skin covered as much as possible. Wear clothing with UV protection.

2. Sun block is essential and should be at minimum SPF 15. Apply every two hours when outside.

3. Shoe wear is important because feet sweat excessively in hot weather. Choose shoes that will ventilate heat and moisture. Socks should propel moisture.

4. Drink up, drink up, drink up! Hydration is essential when working, exercising or walking in a hot environment. Drink several cups of water before and after exposure and a cup at least every one to two hours when outside. Avoid caffeinated and alcoholic beverages.

5. Get out of the sun periodically into shady areas if possible.

6. Consult with your doctor if you should also use salt tablets.

7. If a person is experiencing any symptoms suggestive of heat exhaustion, heat stroke, or a cardiac event, get them out of the sun, hydrate with small sips of water if the person can swallow and seek immediate medical attention.

Comments

No comments on this item Please log in to comment by clicking here