NEW YORK, June 13 (Reuters) -- As summer heats up, health officials warn that hot weather can prove fatal, especially to the very young and the elderly. An average of nearly 400 heat-related deaths occur in the United States each year, health officials say.
A new Centers for Disease Control and Prevention (CDC) report explains that many of those deaths are clearly due to hyperthermia -- a fatal overheating of the body. However, the agency points out that many other deaths may be due to cardiovascular or respiratory diseases exacerbated by high temperatures. When these fatalities are factored in, "deaths attributed to hyperthermia represent only a portion of heat-related excess mortality," the CDC say.
Arizona, Arkansas, Kansas, and Missouri ranked highest in the nation in terms of numbers of heat-related deaths in the period 1979-1994, say agency officials.
The very young and very old are at highest risk. The CDC report one case in Dallas of a 10-month-old girl left alone in a car from 9:30 a.m. until her discovery at 2:45 that same afternoon. Outside temperatures on this hot February day in Texas reached 90 degrees Fahrenheit, and the core body temperature of the baby girl, who was found "unresponsive," was 108 degrees F. She died despite emergency room attempts at cardiopulmonary resuscitation.
In another case, a 61-year-old Texas woman was found dead in her non-air-conditioned bedroom at noon on a summer's day. Although a fan was in operation, room temperature still approached 107 degrees F. Hyperthermia, perhaps in tandem with a heart condition, was listed as the cause of death.
Physical activity in hot weather conditions, coupled with a history of heart disease, can also prove a fatal mix. One 52-year-old Dallas county man collapsed on a neighbor's porch after mowing his lawn in 109 degree F heat. The CDC say his "primary cause of death was listed as hyperthermia," with hypertension and heart disease listed as secondary causes.
Excessive heat can bring on heat stroke. The CDC call heat stroke a "medical emergency" which can escalate within minutes. Its warning signs include lethargy, disorientation, delirium, and coma.
Less dangerous, but still serious, is the heat exhaustion usually brought on by extended exposure to periods of high heat. Dizziness, weakness or fatigue are the main symptoms, and replacement of lost fluids and electrolytes is essential to recovery.
Heat syncope (fainting) and cramps "are usually related to physical exertion during hot weather," according to the CDC. Lying down and electrolyte replacement are the typical treatments for these two conditions.
Some may be more at risk for health-related illness than others. Besides the young and elderly, those taking certain medications (antipsychotics, tranquilizers, some antidepressants, antihistamines, nonprescription sleeping pills, and drugs to counter Parkinson's disease) are also at heightened risk. And another factor: "alcohol consumption may cause dehydration," CDC officials explain, "which increases the risk for heat-related illness."
It is often the isolated, lower-income elderly who are most at risk when temperatures soar. "The elderly should be encouraged and assisted in taking advantage of air-conditioned environments (e.g., shopping malls, public libraries, and heat-wave shelters), even if only for part of the day," say CDC officials. Cool-water baths can help keep body temperatures down as well. However, the CDC warn that fans alone do little to reduce room temperatures, and should not be relied upon for real heat relief.
SOURCE: Morbidity and Mortality Weekly Report (1997;46(23):528-531)
