Sleep apnea is a condition in which breathing stops for brief periods of time while a person is sleeping. These episodes of interrupted breathing last anywhere from 10 to 30 seconds at a time, and may occur up to 20 to 30 times per hour. Over the course of a single night’s sleep, this can mean up to 400 episodes of interrupted breathing.

Normal Upper Airway During Sleep

© 2008 Nucleus Medical Art, Inc.

Every time you stop breathing, you interfere with the normal patterns of deep sleep. You may not even realize it, but you are awakening regularly in order to resume breathing. The quality of sleep that you get is greatly impaired. The next day, your level of alertness and your ability to pay attention may be seriously affected.

Blocked Airway

© 2008 Nucleus Medical Art, Inc.

Some of the risks associated with sleep apnea include:

  • Increased risk of accidents (especially car accidents) due to inattention and inability to stay alert during normal waking hours
  • Higher risk of heart disease
  • Increased risk of stroke
  • Increased risk of lung disease
  • Increased risk of hypertension

There are several different kinds of sleep apnea. These include:

Obstructive Sleep Apnea —This is caused by a temporary airway obstruction. This blockage may be partial or complete. Obstructive sleep apnea can occur when the tissues of your throat relax too much and cave in on each other. If you’re overweight, your excess tissue might be putting too much pressure on your airway, causing it to collapse. You may have a septal deviation, nasal polyps , or an elongated soft palate and uvula that obstruct your airway while you are sleeping.

For children, a common reason for obstructive sleep apnea is enlarged tonsils. The medical term for enlarged tonsils is tonsillar hypertrophy.

Central Sleep Apnea —This occurs when an area of the brain (called the lower brain stem) neglects to send signals to the muscles that control breathing. Conditions that cause problems with the lower brain stem include certain types of polio , encephalitis , stroke , brain tumors , and various degenerative diseases affecting the brain and central nervous system.

Mixed Sleep Apnea —This form includes aspects of both obstructive and central sleep apnea.

Only about one million people have been definitively diagnosed with sleep apnea at any given time; however, public health estimates of the problem suggest that as many as 18 to 25 million people have the disorder and don’t know it.