title: Heat-related mortality.
abstract: It is known that death rates rise during hot spells. Major physiologic mechanisms for heat loss are convection by transferring heat from the skin to the air and evaporation produced by sweat. An inability to increase cardiac output because of cardiovascular disease, drugs or water depletion or to increase sweating because of drugs with anticholinergic properties can considerably impair heat tolerance. If exposed to heat, looking for a cooler place is an important coping strategy but this is impossible for those who are immobile or have a psychiatric disorder.