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Sleep Apnea

What Is Sleep Apnea?

Sleep apnea is a disorder characterized by repeated cessation of breathing for brief periods during sleep. There are two basic forms of apnea: obstructive sleep apnea (the most common form) and central sleep apnea.

Obstructive sleep apnea is commonly associated with obesity in middle-aged men. The condition is attributed to excessive relaxation of the muscles at the back of the throat during sleep, which may obstruct the upper airway either partially (hypoapnea) or completely (apnea) a dozen to hundreds of times a night. After 10 to 100 seconds, the demand for oxygen grows critical, and the sleeper gasps or snores abruptly in characteristically loud, staccato bursts in the struggle to regain normal breathing.

In central sleep apnea, which is far less common, the airway remains open but the chest muscles and diaphragm don’t always receive the appropriate brain signals to expand the lungs properly. Central sleep apnea syndromes include central alveolar hypoventilation (Ondine’s Curse) and obesity-hypoventilation (Pickwickian syndrome). People with obesity hypoventilation will frequently also have obstructive sleep apnea. Sometimes, sleep apnea events are due to airway obstruction combined with a central sleep apnea component.

The sleeper rarely awakens fully during these gasping episodes, but tends to arise tired and unrefreshed the next morning because apnea prevents the sufferer from reaching deeper stages of sleep. Severe, persistent cases of sleep apnea may promote serious cardiovascular problems such as high blood pressure, abnormal heart rhythms, and heart failure.

Who Gets Sleep Apnea?

Sleep apnea affects anywhere from 2% to 10% of adults, yet the condition is still under diagnosed. Family members may tell you that you stop breathing at night and snore excessively. If you sleep alone, you may not even know that you snore, and you may not link the possible consequences of apnea to the disorder. Since apnea prevents you from sleeping restfully, and robs you of restorative REM (rapid eye movement) sleep, it can lead to daytime drowsiness, irritability, faulty memory, and lack of ability to concentrate.


  • Breathing cessation interrupted by loud, abrupt bursts of snoring or snorting.
  • Waking up abruptly at night.
  • Excessive daytime sleepiness.
  • Morning headache.
  • Cough, dry mouth, and sore throat upon waking.
  • Difficulty concentrating; memory loss; personality changes.

Causes/Risk Factors

  • Excess body weight combined with loss of muscle tone at the base of the throat is associated with obstructive sleep apnea.

  • Alcohol and sedatives promote apnea.

  • Men have a greater risk than women for sleep apnea.

  • In children, enlarged tonsils and adenoids are the main causes of sleep apnea.

  • Incidence increases with age.

  • The cause of central sleep apnea is often unknown, but other medical conditions such as congestive heart failure or pain medications like morphine are associated with central sleep apnea.

What If You Do Nothing?

The snoring and other symptoms associated with sleep apnea are unlikely to improve without some form of intervention—at the very least, weight loss for those who are overweight. The decreased alertness places a person at risk in a variety of potentially hazardous situations. It is recommended that persons with excessive daytime sleepiness not drive or operate dangerous equipment until their condition is effectively treated. In addition, untreated sleep apnea also increases the risk of cardiovascular conditions, especially hypertension and atrial fibrillation, the most common cardiac arrhythmia.


  • Patient history and physical examination are necessary. History may include reports from roommates or bedmates. A tape recording of nighttime snoring may also be useful in making a diagnosis.
  • Further evaluation at a sleep center may be recommended to pinpoint causes and treatment. Electronic monitors attached to a patient can record nighttime breathing and other activity that enable a doctor to diagnose sleep apnea. Some people may be able to undergo monitoring at home using portable equipment.
  • Laboratory tests may include chest x-rays, electroencephalogram, electrocardiogram, and tests of blood-oxygen levels, chest wall movement, and air movement through the nose and mouth during sleep.


  • Continuous positive airway pressure (CPAP) is considered the most effective nonsurgical treatment for sleep apnea and is now widely used. With CPAP, a mask is worn over the nose or nose and mouth; air is forced through the mask throughout the night to keep the throat open. CPAP works only as long as you use the device and use it correctly.
  • Losing excess weight is crucial. Even a reduction of 10 percent will likely help.
  • Avoid alcohol, smoking, and medications that make you sleepy. Also try not to eat heavy meals in the evening.
  • A tennis ball may be sewn to the back of pajamas to prevent sleeping on one’s back, a position that encourages episodes of sleep apnea.
  • A custom-fitted mouthpiece is helpful for some people with mild to moderate sleep apnea. Made and fitted by a dentist or orthodontist, the mouthpiece repositions the lower jaw and tongue to help keep the throat open during sleep.
  • A Pillar implant procedure is an option for people who have mild to moderate sleep apnea. The procedure involves inserting three support devices (pillars) into the soft tissue at the back of the roof of the mouth to prevent it from sagging and obstructing the airway during sleep.
  • Surgery can help improve breathing in some cases. In general, surgery is performed only on people who have severe apnea that has not responded to other treatments. The most common type of surgery involves removal of the uvula (the piece of tissue that hangs from the roof of the back of the mouth). In some cases, the tonsils and adenoids might also be removed.
  • In children, where the cause of sleep apnea is usually tonsil and adenoid enlargement, surgical removal of the enlarged tonsils and adenoids is the treatment of choice.
  • A nasal valve that blocks the flow of air out of the nostrils thereby keeping the airway open is an option for more mild cases of obstructive sleep apnea.
  • Implantation of an electronic stimulator in a nerve in the throat (hypoglossal nerve) has recently shown promise in treating patients with obstructive sleep apnea who do not tolerate CPAP.


  • Maintain a healthy weight.

  • Avoid sleeping pills and do not consume alcoholic beverages within two or three hours of bedtime.

When To Call Your Doctor

  • Make an appointment with a doctor if you develop extremely loud snoring with periods of silence, or if daytime sleepiness interferes with normal activities.

Reviewed by Allen J. Blaivas, D.O., Division of Pulmonary, Critical Care, and Sleep Medicine, VA New Jersey Health Care System, Clinical Assistant Professor, Rutgers New Jersey Medical School, East Orange, NJ. Review provided by VeriMed Healthcare Network.