Body Language

Not Too Cool

Tuesday, December 20, 2005

So you're inching that thermostat down toward 60, hoping to save a buck this winter, but your spouse is screaming hypothermia. Depending on age and health, he/she may have a case. Hypothermia, a potentially fatal lowering of body temperature, isn't just an outdoor phenomenon. Older people -- especially those living alone or with chronic conditions -- are particularly vulnerable, says Lee A. Green, an associate professor in the Department of Family Medicine at the University of Michigan Medical School.

What Goes On? As we age, our body's ability to regulate temperature is impaired, Green says. Heat-generating muscle mass shrinks and we shiver less -- missing that chance to bump up the heat. Cold air can lower body temperature, causing blood vessels to constrict; blood volume decreases and the kidneys stop filtering efficiently. A reduced volume of body fluid concentrates any medications you're taking, effectively delivering an overdose. Hypothermia's early signs include foggy-headedness and slurred speech -- often hard to recognize in yourself. Hypothermia symptoms "are very insidious," says Eduardo Azziz-Baumgartner, medical epidemiologist at the Centers for Disease Control and Prevention. "You can get into trouble before you know it." Effects are exacerbated by alcohol, sleep medications and other common drugs.

Killer Cold Hypothermia kills about 700 people in the United States each year, says Azziz-Baumgartner; how many die indoors isn't known. One study showed that about half of the 63 Alabamans who succumbed to hypothermia from 1983 to 1999 were indoors when they died.

Bundle Up There's no magic temperature at which hypothermia sets in, Green says: Tolerances for cold vary. If you keep your house ultra-cool, dress in layers and consider wearing a cap. (The head loses lots of body heat.) Check in regularly on elderly people living alone, Azziz-Baumgartner suggests, and seek immediate medical attention if you suspect hypothermia.

-- Jennifer Huget

© 2005 The Washington Post Company