Heat-related illness, injuries and deaths are
preventable. High environmental temperatures,
such as during heat waves, have been associated
with increased mortality, but the effect of hot
weather on human mortality is likely
A new report from the CDC describes four
instances of heat-related deaths that occurred in
the cities of Cincinnati and Dayton, Ohio during the
1999 summer heat wave, summarizes heat-related
deaths in the United States during 1979-1997, and
describes the risk factors associated with
heat-related illness and death. Persons at increased risk for heat-related
illness and death include infants, the elderly (>65 years), persons with
impaired mobility, persons physically active in hot environments who fail to
rest frequently or drink enough fluids, and persons using certain drugs or
consuming excessive amounts of alcohol.
During 1979--1997, the most recent years for which data are available, an annual average of 371 deaths in the United States were attributable to "excessive heat exposure" (median: 249; range: 148 in 1979 to 1700 in 1980). This translates into a mean
annual death rate of 1.5 per million and a median annual death rate of one per million.
Because of a record heat wave, the
heat-related death rate for 1980 was more than three times higher than that for any other year during the 19-year period. The
median annual death rate for hyperthermia in persons aged >65 years was three per million. During 1979--1997, 7046 deaths were
attributable to excessive heat exposure: 3010 (43%) were "due to weather conditions," 351 (5%) to heat "of manmade origin," and
3683 (52%) "of unspecified origin." Of the 2954 persons whose deaths were caused by weather conditions and for whom age data
were available, persons aged >65 years accounted for 1783 (44%) deaths, and persons aged <14 years accounted for 127 (4%)
deaths. Except children aged <14 years, the average annual rate of heat-related deaths increased with each age group, particularly
for persons aged >65 years.
During 1979--1997, among persons of all ages, the annual death rate "due to weather
conditions" was two times higher for men (0.8 per million) than for women (0.4 per million), and more than three times higher for
blacks (1.6 per million) than for whites (0.5 per million). Arizona and Missouri (four per million) and Arkansas and Kansas (three
per million) had the highest annual age-adjusted rates for heat-related deaths "due to weather conditions".