Sleep apnea is a sleep disorder characterized by abnormal pauses in breathing or instances of abnormally low breathing, during sleep. This prevents air from entering the lungs and forcing the person to wake briefly to start breathing again before falling back to sleep. The person with sleep apnea is usually unaware of this. Each pause in breathing, called an apnea, can last from a few seconds to minutes, and may occur 5 to 30 times or more an hour. As a result, people with sleep apnea feel excessively sleepy during their normal waking hours.
Left untreated, sleep apnea can lead to high blood pressure, diabetes, heart attack, stroke, impotence and even death. Sleep apnea is diagnosed with an overnight sleep test called a polysomnogram, or “sleep study”.