Page last reviewed: November 16, 2023

Elderly at risk for heat-related illnesses

July 3, 2002

Houston’s sweltering summer months render the elderly particularly vulnerable to heat-related illnesses.

Last summer in Houston and Harris County, senior citizens accounted for 14 of the 20 heat-related deaths reported to the Houston Department of Health and Human Services. A total of 38 heat-related deaths occurred in Harris County in the summer of 2000 and 20 deaths in the summer of 1999.

"The ability to respond to thermal stress, either heat or cold, is impaired in the elderly," said Dr. Luther Harrell, Chief Physician with the department’s Division of Community and Personal Health Services. "It takes older people almost twice the time of younger people to return to core body temperature after exposure to extreme outdoor temperatures."

High body temperatures can also lead to damage to the brain or other vital organs.

Harrell recommends that people visit elderly relatives, friends or neighbors and check them for signs of heat exhaustion or heat stroke. Checking an elderly person’s condition and determining the temperature inside the home is especially important during the hottest parts of the summer.

Heat exhaustion, usually associated with heavy activity, is the body’s response to an excessive loss of water and salt contained in sweat. Signs include profuse sweating, paleness, muscle cramps, weakness, dizziness, headache, nausea or vomiting, a weak-but-rapid pulse and fainting. The skin may be cool and moist. If heat exhaustion is untreated, it may progress to heat stroke.

Heat stroke occurs when the body’s temperature rises rapidly, the sweating system fails and the body is unable to cool down. Body temperature may rise to 106°F or higher within 10 to 15 minutes. Heat stroke can cause death or permanent disability if emergency treatment is not given.

Heat stroke symptoms include an extremely high body temperature (above 103°F, orally), red, hot and dry skin (no sweating), rapid and strong pulse, throbbing headache, dizziness, nausea, confusion and unconsciousness.

Others who are particularly vulnerable include infants and children up to four years of age, those who are overweight and people with heart and respiratory problems.

Staying indoors, preferably in an air-conditioned home or building such as a library, shopping mall or multi-service center, is the best protection against the heat. Electric fans may provide comfort, but when the temperature is in the 90s, fans without refrigerated air only spur the movement of hot humid air, which will accelerate body heating and raise internal body temperature. Taking a cool shower or bath or moving to an air-conditioned place is a much better way to cool off.

To avoid heat-related illness:

  • Increase water consumption. Drink lots of liquids even before getting thirsty, but avoid those with caffeine, alcohol or large amounts of sugar because these can actually result in the loss of body fluid.
  • Conduct outdoor work or exercise in the early morning or evening when it is cooler. Outdoor workers should drink plenty of water or electrolyte-replacement beverages and take frequent breaks in the shade or in an air-conditioned facility. Those unaccustomed to working or exercising in a hot environment need to start slowly and gradually increase heat exposure over the weeks.
  • Wear light-colored, loose fitting clothing that permits the evaporation of perspiration.
  • Avoid direct sunlight; seek shade when available.
  • A wide-brimmed hat helps prevent sunburn as well as heat-related illness. Sunscreen also protects from the sun’s harmful rays and reduces the risk of sunburn.
  • If the house is not air-conditioned, seek accommodations in air-conditioned facilities during the heat of the day: malls, movie theaters, libraries, multi-service centers, etc.
  • Take frequent cool baths or showers.
  • Never leave a person or a pet inside a closed, parked car during hot weather.
  • Stay alert to heat advisories. The National Weather Service issues a heat advisory when the heat index, a computation of the air temperature and humidity, reaches 108 degrees on two consecutive days.