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Heat-Wave-Related Morbidity and Mortality

Recent record-high temperatures in many parts of the United States highlight the need for awareness of the health hazards posed by environmental heat. Heat waves can cause dramatic increases in overall mortality; they have doubled or even tripled the usual number of deaths per day in particularly severe episodes.

Heatstroke, usually diagnosed in a heat-exposed individual whose core temperature is 40.5*SDC (105*SDF) or greater, is the most serious of diseases clearly attributable to the heat. It has a high death-to-case ratio. Elderly persons, residents of poorer inner-city neighborhoods, patients taking neuroleptic or anticholinergic medications, and persons confined to bed or otherwise unable to care for themselves are at particularly high risk (1). Reducing physical activity, drinking extra liquids, and increasing time spent in air-conditioned places all appear to significantly reduce the risk of heatstroke. Measures to prevent heatstroke should target persons at high risk and should promote behaviors associated with reduced risk--for example, elderly persons may be taken to an air-conditioned shopping mall for 2-3 hours per day. Special precautions should be taken to protect workers in certain "hot" industries. Reported by: Division of Environmental Hazards and Health Effects, Center for Environmental Health and Injury Control, CDC. Reference

  1. Kilbourne EM, Choi K, Jones TS, Thacker SB, and the Field Investigation Team. Risk factors for heatstroke: A case-control study. JAMA 1982;247:3332-6.

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