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Apnea, Sleep

It is possible that the main title of the report Apnea, Sleep is not the name you expected. Please check the synonyms listing to find the alternate name(s) and disorder subdivision(s) covered by this report.


Disorder Subdivisions

General Discussion

Sleep apnea is a sleep disorder characterized by temporary, recurrent interruptions of breathing (respiration) during sleep. Symptoms of this disorder include periodic wakefulness during the night, excessive sleepiness during the day, and loud snoring during sleep. People with this disorder are frequently overweight. Diagnosis and treatment of sleep apnea can avoid serious medical problems that may arise as a consequence of oxygen deprivation in untreated individuals. Sleep apnea occurs in three different forms: obstructive, central, and mixed.

An individual's rate of respiration is regulated by group of nerve cells in the brain that control the rhythm of breathing in response to changing oxygen levels in the blood (respiratory drive). In some apneas, the respiratory drive is abnormal. Obstructive sleep apnea (upper airway apnea) the most common form of sleep apnea, results from the blockage of the respiratory passages during sleep. Affected individuals may struggle to breathe and experience increased respiratory effort. Respiratory drive is unaffected in people with this form of sleep apnea but the blockage prevents them from breathing normally. Obstructive apnea is more likely than central apnea to be associated with snorting and arousal from sleep.

In the rare central sleep apnea, the brain does not send adequate signals to the diaphragm and lungs during sleep, resulting in low respiratory drive. In this form of sleep apnea, breathing stops and does not resume until the oxygen-deprived brain finally sends impulses to the diaphragm and lungs. In infants, central sleep apnea is defined as lasting 20 seconds or more.

Mixed sleep apnea is a combination of improper brain signals and obstruction of the respiratory passages. In some cases, sleep apnea is referred to as "Pickwickian Syndrome." In these cases, obstructive apnea is combined with obesity and an abnormally short neck. Infantile sleep apnea affects children less than one year old, and its cause is unknown. (For more information on infantile sleep apnea, see the Related Disorders section of this report.)


National Sleep Foundation
1010 N. Glebe Road
Suite 310
Arlington, VA 22201
Tel: (703)243-1697

Narcolepsy Network, Inc.
129 Waterwheel Lane
North Kingstown, RI 02852
Tel: (401)667-2523
Fax: (401)633-6567
Tel: (888)292-6522

American Sleep Association
1610 14th Street NW
Suite 300
Rochester, MN 55901
Tel: (507)287-6006
Fax: (507)287-6008

Tri-State Sleep Disorders Center
1275 E. Kemper Rd.
Cincinnati, OH 45246
Tel: (513)671-3101
Fax: (513)671-4159
Tel: (800)838-4322
TDD: (311)111-6111

American Sleep Apnea Association
6856 Eastern Ave NW
Suite 203
Washington, DC 20012
Tel: (202)293-3650
Fax: (202)293-3656

NIH/National Institute of Neurological Disorders and Stroke
P.O. Box 5801
Bethesda, MD 20824
Tel: (301)496-5751
Fax: (301)402-2186
Tel: (800)352-9424
TDD: (301)468-5981

Genetic and Rare Diseases (GARD) Information Center
PO Box 8126
Gaithersburg, MD 20898-8126
Tel: (301)251-4925
Fax: (301)251-4911
Tel: (888)205-2311
TDD: (888)205-3223

For a Complete Report:

This is an abstract of a report from the National Organization for Rare Disorders (NORD). A copy of the complete report can be downloaded free from the NORD website for registered users. The complete report contains additional information including symptoms, causes, affected population, related disorders, standard and investigational therapies (if available), and references from medical literature. For a full-text version of this topic, go to and click on Rare Disease Database under "Rare Disease Information".

The information provided in this report is not intended for diagnostic purposes. It is provided for informational purposes only. NORD recommends that affected individuals seek the advice or counsel of their own personal physicians.

It is possible that the title of this topic is not the name you selected. Please check the Synonyms listing to find the alternate name(s) and Disorder Subdivision(s) covered by this report

This disease entry is based upon medical information available through the date at the end of the topic. Since NORD's resources are limited, it is not possible to keep every entry in the Rare Disease Database completely current and accurate. Please check with the agencies listed in the Resources section for the most current information about this disorder.

For additional information and assistance about rare disorders, please contact the National Organization for Rare Disorders at P.O. Box 1968, Danbury, CT 06813-1968; phone (203) 744-0100; web site or email

Last Updated: 2/20/2007
Copyright 1986, 1987, 1989, 1992, 1993, 1995, 1996, 1998, 2000, 2007 National Organization for Rare Disorders, Inc.

WebMD Medical Reference from the National Organization for Rare Disorders

Last Updated: May 28, 2015
This information is not intended to replace the advice of a doctor. Healthwise disclaims any liability for the decisions you make based on this information.

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