The elderly are at particular risk for heat illness. People suffer heat-related illness when their bodies are unable to properly cool themselves. The body normally cools itself by sweating. When humidity levels are high, sweat will not evaporate as quickly, preventing the body from releasing heat quickly.

Other conditions lending themselves to increased risk are obesity, fever, dehydration, heart disease, mental illness, poor circulation, sunburn, prescription drug-use and alcohol use.

Air conditioning provides the best protection from heat exposure and heat-related deaths. However, some people may be fearful of high utility bills and limit their use of air conditioning. This places people who may already be at risk for heat illness at increased risk.

Many people think electric fans are sufficient during extreme heat. Fans may provide comfort, but they will not prevent heat-related illness when the temperature is in the high 90s.

Heat stroke is a severe illness that occurs when the body is unable to regulate its temperature. The body's temperature rises rapidly, the sweating mechanism fails, and the body is unable to cool down. Body temperature may rise to 106 degrees Fahrenheit or higher within 10 to 15 minutes. This type of heat-related illness can cause death or permanent disability if emergency treatment is not provided.

Warning signs of heat illness vary but may include:
• extremely high body temperature (above 103 degrees Fahrenheit)
• red, hot and dry skin (no sweating)
• throbbing headache
• dizziness, nausea and confusion
• unconsciousness

Heat exhaustion is a milder form of heat-related illness that can develop after several days of exposure to high temperatures and inadequate or unbalanced replacement of fluids. If left untreated, it can progress to more serious heat stroke.
• Limit your outdoor activity to morning and evening hours.
• Cut down on physical activity.
• Drink plenty of water.

sources:
http://www.webmd.com/a-to-z-guides/heat-stroke
http://www.nia.nih.gov/NR/rdonlyres/054BF690-7A7D-4FE4-A69B-0EC27E7B1DE7/15257/HyperthermiaAP.pdf

Reviewed July 22, 2011
by MIchele Blacksberg R.N.
Edited by Jody Smith