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THURSDAY, Jan. 24 (HealthDay News) -- As extreme cold blankets many parts of the United States, one expert warns that frigid temperatures can put people at greater risk not only for hypothermia and frostbite, but also for stroke, heart attack and asthma flare-ups.
Even if you're in excellent physical condition, you should take extremely cold conditions seriously, Dr. Kevin Marzo, chief of cardiology at Winthrop-University Hospital in Mineola, N.Y., cautioned in a hospital news release.
When people face freezing temperatures, their arteries constrict. Narrow arteries can reduce blow flow throughout the body and put stress on the heart. For older people, potentially harmful effects of the cold can be even more serious, Marzo noted.
The number of heart attacks increases by an estimated 53 percent in the winter and the cold-weather constriction of the arteries can also increase people's blood pressure and their risk for stroke. Those with high blood pressure should take extra precautions when dressing for freezing temperatures.
Cold weather can also trigger asthma flare-ups. When people with the condition inhale dry, cold air they may experience bronchospasms, or contractions of the air passages in their lungs. As a result, people with asthma should take their medication before they engage in a physical activity outside, Marzo recommended.
People with circulatory problems, such as Raynaud's disease, should also avoid exercising outdoors when it's extremely cold. In Raynaud's, cold temperatures cause spasms in the blood vessels and cut off circulation to fingers and toes.
Exposure to freezing temperatures can also result in hypothermia, or abnormally low body temperature. When people's body temperature is too low their brain function is affected, Marzo explained. As a result, they are not able to think clearly or move well. The following symptoms are warning signs for hypothermia:
Anyone with signs of hypothermia should receive emergency medical attention, particularly if their body temperature falls below 95 degrees Fahrenheit.
If medical attention is delayed or not available, bystanders should move the person with hypothermia to shelter or a warm room. Any wet clothing should be removed. The center of the body should be warmed first with heated blankets or skin-to-skin contact under layers of dry blankets, sheets or towels.
Warm drinks can help a person with hypothermia, as long as they are not alcoholic beverages. Alcohol can cause the body to lose heat more rapidly, Marzo pointed out. He recommended victims be given warm, sweet beverages such as hot chocolate to help maintain their body temperature.
In frostbite, exposure to freezing temperatures causes numbness and a loss of color in the affected areas. In extreme cases, it can permanently damage the body, and result in amputation. Areas such as the nose, ears, cheeks, chin, fingers or toes are most vulnerable to frostbite.
As soon as skin becomes numb, appears red, white or grayish-yellow or feels unusually firm or waxy, it's time to warm up and get out of the cold, Marzo cautioned.
Among the steps people can take to protect themselves from the cold is to wear the appropriate clothing. Marzo recommended that adults and children alike wear the following:
The outer layer of clothing should be tightly woven and wind-resistant if possible. Underneath, people should wear wool, silk, or polypropylene layers, which will trap more body heat than cotton fabric.
To stay warm in the extreme cold, it's also important to stay dry, Marzo said. Even sweat can increase heat loss, so wet or unnecessary layers should be removed. It's also important to avoid spilling gasoline or alcohol on your skin outdoors in the winter, since they will speed up heat loss from the body.
Listen to your body, Marzo concluded. Shivering is often the first sign that the body is losing too much heat and it's time to warm up. Eating well-balanced meals is also key to staying warm when it's cold outside, he said.
The U.S. Centers for Disease Control and Prevention provides more tips on how to stay safe in the extreme cold.