CD-ROM Today 1996 January/CD-ROM Today 1996 January.iso/dp/0348/03483.txt

Text File | 1994-01-17 | 14.9 KB | 331 lines

$Unique_ID{BRK03483}
$Pretitle{}
$Title{Apnea, Sleep}
$Subject{Apnea, Sleep Obstructive Sleep Apnea (Upper Airway Apnea) Pickwickian
Syndrome Central Sleep Apnea Mixed Sleep Apnea Narcolepsy Congenital Central
Hypoventilation Syndrome Infantile Sleep Apnea}
$Volume{}
$Log{}

Copyright (C) 1986, 1987, 1989, 1992, 1993 National Organization for Rare
Disorders, Inc.

68:
Apnea, Sleep

** IMPORTANT **
It is possible that the main title of the article (Sleep Apnea) is not
the name you expected.  Please check the SYNONYMS listing to find the
alternate name and disorder subdivisions covered by this article.

Synonyms

Disorder Subdivisions:

     Obstructive Sleep Apnea (Upper Airway Apnea)
     Pickwickian Syndrome
     Central Sleep Apnea
     Mixed Sleep Apnea

Information on the following diseases can be found in the Related
Disorders section of this report:

     Narcolepsy
     Congenital Central Hypoventilation Syndrome
     Infantile Sleep Apnea

General Discussion

** REMINDER **
The Information contained in the Rare Disease Database is provided for
educational purposes only.  It should not be used for diagnostic or treatment
purposes.  If you wish to obtain more information about this disorder, please
contact your personal physician and/or the agencies listed in the "Resources"
section of this report.


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 patients.

Sleep Apnea occurs in several forms.  In some apneas, breathing
(respiratory) drive is normal while in others it is abnormal.  The 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).  Obstructive Sleep Apnea (upper airway apnea), is the
most common form of Sleep Apnea.  It results from the blockage of the
respiratory passages during sleep.  Respiratory drive is normal in people
with this form of Sleep Apnea but the blockage prevents them from breathing
normally (see Symptoms section below).
In the rarer 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-starved brain finally sends impulses to the diaphragm and
lungs, and breathing resumes.

Sleep Apnea is sometimes referred to as "Pickwickian Syndrome" when
Obstructive Apnea is combined with obesity and a short neck.  Infantile Sleep
Apnea affects children and its cause is unknown (see Related Disorders
section of this report).

Symptoms

The most common symptoms of Sleep Apnea include excessive daytime sleepiness
and loud snoring during the night.  In Obstructive Apnea, labored breathing
during sleep is interrupted by the narrowing (constriction) of airways.  The
episode ends when the muscles of the diaphragm and the chest build up
sufficient pressure to force the airway open.  Partial awakening then occurs,
as the person gasps for air; sleep is resumed as breathing begins again.
This cycle may be repeated many times during the night, and may lead to sleep
deprivation.  A person may wake in the morning feeling as if he/she has
hardly slept.

If Sleep Apnea is not treated, various complications may occur.  These
include high blood pressure (hypertension), irregular heartbeats
(arrhythmias), abnormal blood levels of oxygen and carbon dioxide, and
swelling due to the accumulation of fluid in the arms and/or legs (peripheral
edema).  Other possible complications of untreated Sleep Apnea include heart
disease and, brain damage due to lack of oxygen, sleepwalking, blackouts,
automatic "robot-like" behavior, hallucinations, anxiety, irritability, and
behaviors that are characteristic of sleep deprivation.  Loss of interest in
sex, morning headaches, and bed wetting may also occur with time in people
with Sleep Apnea.

Causes

Several physical conditions are often (but not always) associated with
Obstructive Sleep Apnea.  These include obesity, a short thick neck, and
reduction in muscle tone in the roof of the mouth (soft palate), the uvula,
and the throat (pharynx).  The upper airway may be narrowed by abnormally
enlarged tonsils or adenoids, a deviated nasal septum, polyps in the nose, or
congenital abnormalities.  At high altitudes sleep disruption may occur
because of the low oxygen concentration in the air.

Central Apnea and the associated unstable respiratory control in the
brain may be the result of an abnormally high partial pressure of carbon
dioxide (portion of total blood gas pressure) in the blood.  This form of
Sleep Apnea may also be associated with a decrease in the rate of metabolism
during sleep.  Central Sleep Apnea may also be caused by lesions in the brain
stem (primary respiratory neurons of the medulla) or in the spinal cord
(descending cervical pathways) which control the rate of respiration
(respiratory drive).

In some cases Obstructive Sleep Apnea is thought to be inherited as an
autosomal dominant genetic trait.  Human traits, including the classic
genetic diseases, are the product of the interaction of two genes, one
received from the father and one from the mother.  In dominant disorders a
single copy of the disease gene (received from either the mother or father)
will be expressed "dominating" the other normal gene and resulting in the
appearance of the disease.  The risk of transmitting the disorder from
affected parent to offspring is fifty percent for each pregnancy regardless
of the sex of the resulting child.

Affected Population

Sleep Apnea is a common sleep disorder that affects approximately 2.5 million
people in the United States.  Males are affected by this disorder more often
than females, outnumbering premenopausal females 30 to 1.  Many individuals
affected by Sleep Apnea are at least 20 percent above ideal body weight.
Most people with Sleep Apnea are not properly diagnosed and they tend to
blame their chronic tiredness on other lifestyle factors.

Recent studies indicate that approximately two percent of women and four
percent of men in the middle-age work force meet the minimal criteria for
sleep apnea.  Both men and women who snore habitually tend to have a higher
incidence of sleep apnea.  It is felt that the occurrence of undiagnosed
sleep apnea is high among men and much higher than previously thought in
women.

Related Disorders

Symptoms of the following disorders can be similar to those of Sleep Apnea.
Comparisons may be useful for a differential diagnosis:

Narcolepsy is a rare neurological sleep disorder characterized by
excessive drowsiness during the day, and the inability to resist sleep.
Sleep attacks, called cataplexy, can include extreme muscle weakness,
hallucinations, and paralysis while sleeping.  The symptoms of this disorder
typically begin between the ages of 10 and 20 years and symptoms vary greatly
from patient to patient.  Exaggerated daytime drowsiness is usually the first
symptom of Narcolepsy.  Sleep attacks can be triggered by extreme emotions
such as laughing or surprises, or quiet environments such as listening to a
lecture or television.  (For more information on this disorder, choose
"Narcolepsy" as your search term in the Rare Disease Database.)

Congenital Central Hypoventilation Syndrome is a rare neurological
disorder characterized by the dysfunction of that portion of the brain that
regulates respiration.  The disorder typically affects infants, but may also
occur in adolescents and adults.  The primary symptom of Congenital Central
Hypoventilation Syndrome is an abnormally slow rate of respiration while
sleeping (nocturnal hypoventilation).  (For more information on this
disorder, choose "Central Hypoventilation" as your search term in the Rare
Disease Database.)

Infantile Sleep Apnea is a neurological disorder of infancy characterized
by the temporary cessation of breathing as a result of the abnormal function
of the area of the brain that controls respiration.  Infantile Apnea is
defined as an apnea occurring in children less than 1 year old.  Infants with
this disorder stop breathing temporarily which can result in low levels of
oxygen in the blood and an abnormally slow heartbeat.  (For more information
on this disorder, choose "Infantile Apnea" as your search term in the Rare
Disease Database.)

Therapies:  Standard

Chronic daytime tiredness and loud snoring with periodic gasping for breath
during the night should be a warning sign that evaluation at a sleep
disorders clinic is warranted.  Diagnosis of Sleep Apnea requires evaluation
at a sleep disorder center where overnight testing for at least one night, or
daytime sleep tests that monitor respiration, can be performed.  (See
Association of Sleep Disorder Centers in the Resources section of this
report.)

Treatment of mild cases of Obstructive Sleep Apnea usually consists of
sleeping in a recliner chair, or elevating the bed's headposts by 6 to 8
inches.  Elevation of the head can keep the tongue from falling backward and
blocking the upper airway if the tongue causes the obstruction.  In some
cases drugs may be used to stimulate breathing including theophylline,
tricyclic antidepressants such as protriptyline and clomipramine, central
nervous system stimulants such as pemoline or tranquilizers such as
thioridazine.  The drug nicotine initially stimulates nerve impulses and
subsequently (in high doses), inhibits nerve impulses.

Some people are diagnosed with Positional Sleep Apnea that occurs while
sleeping in certain positions that cause a breathing obstruction.  Sewing a
bulky object in the back of the sleeping garment can make sleeping on the
back (supine) so uncomfortable that the person turns over.  This clears the
obstruction to the airways that causes this type of Sleep Apnea.

Patients with either Central or Obstructive Sleep Apnea that is not
caused by a sleeping position, are treated with a medical device called
Continuous Positive Airway Pressure (CPAP).  At night the patient's nose is
connected through a tube to the CPAP machine which is about the size of a
small television.  This device forces air through the tube at low pressure,
just sufficient to keep the patient's upper airway open and permit air to
enter the lungs.  It is designed not to harm the patient should it
malfunction or the power fail.  The pressure is set to fit the patient's own
breathing pattern as determined by sleep testing.  The device must be
prescribed by a doctor.  Approximately 85% of Obstructive Sleep Apnea
patients are helped with this type of device; oxygen levels return to normal
and excessive daytime sleepiness disappears.

A surgical technique that is sometimes used in people who do not adjust
to the CPAP device is uvulo-palato-pharyngoplasty (UPPP).  Loose tissues are
tightened in the back of the mouth and top of the throat, and excess tissues
that block the airway in those areas are trimmed away.  UPPP has been helpful
in about 55 percent of patients with Obstructive Sleep Apnea who have
undergone this surgery.

Therapies:  Investigational

Clinical trials are underway to study diaphragm pacing for people with Sleep
Apnea who do not respond to other treatments.  For more information, patients
may have their physicians contact:

     Dr. J. Elefteriades
     Cardiothoracic Surgery
     Yale School of Medicine
     121 FMB
     333 Cedar St.
     New Haven, CT  06510
     [phone]

This disease entry is based upon medical information available through
May 1993.  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.

Resources

For more information on Sleep Apnea, please contact:

     National Organization for Rare Disorders (NORD)
     P.O. Box 8923
     New Fairfield, CT  06812-1783
     [phone]

     Sleep Apnea Support Society (SASS)
     P.O. Box 59728
     Chicago, IL  60659-0728

     American Sleep Apnea Association
     P.O. Box 3893
     Charlottesville, VA  22903

     Awake Network, c/o Lucie Seger
     Presbyterian University Hospital
     Sleep Evaluation Network
     DeSoto at O'Hara Streets
     Pittsburgh, PA  15213

     American Narcolepsy Association, Inc.
     425 California St.
     San Francisco, CA  94104
     [phone]

     Narcolepsy and Cataplexy Foundation of America
     1410 York Ave., 32-D
     New York, NY  10021
     [phone]

     Narcolepsy Network
     FDR Station, Box 1365
     New York, NY  10150

     NIH/National Institute of Neurological Disorders & Stroke (NINDS)
     9000 Rockville Pike
     Bethesda, MD  20892
     [phone]
     [phone]

References

MENDELIAN INHERITANCE IN MAN, 10th Ed.:  Victor A. McKusick, Editor:  Johns
Hopkins University Press, 1992.  Pp. 103.

CECIL TEXTBOOK OF MEDICINE, 19th Ed.:  James B. Wyngaarden, and Lloyd H.
Smith, Jr., Editors; W.B. Saunders Co., 1990.  Pp. 454-455, 2066-2067.

THE MERCK MANUAL, 16th Ed.:  Robert Berkow Ed.; Merck Research
Laboratories, 1992.  Pp. 1445-1449.

DISEASES OF THE NOSE, THROAT, EAR, HEAD & NECK, 14TH Ed.; John Jacob
Ballenger, Lea & Febiger, 1991.  Pp. 246-247.

PRINCIPLES OF NEUROLOGY, 4th Ed.; Raymond D. Adams, M.D. and Maurice
Victor, M.D., Editors; McGraw-Hill Information Services Company, 1989.  Pp.
313-16.

SNORING BY NIGHT?  SNOOZING BY DAY?  SOUNDS LIKE SLEEP APNEA:  Harold
Hopkins; FDA Consumer (December 1986 - January 1987).  Pp. 29-32.

NASAL CPAP THERAPY, UPPER AIRWAY MUSCLE ACTIVATION, AND OBSTRUCTIVE SLEEP
APNEA:  K.P. Strohl, et. al.; American Review of Respiratory Diseases
(September 1986).  Pp. 555-558.

THE EFFECTS OF POSTURE ON OBSTRUCTIVE SLEEP APNEA:  R. D. McEvoy, et.
al.;  American Review of Respiratory Diseases (April 1986:  issue 133,4).  Pp.
662-666.

CLINICAL FEATURES AND TREATMENT OF OBSTRUCTIVE SLEEP APNEA.  R.J. Kimoff
et al.; Can Med Assoc J (March 1991:  144(6)).  Pp. 689-695.

MECHANISMS OF OBSTRUCTIVE SLEEP APNEA.  D.W. Hudgel; Chest (Feb 1992;
101(2)).  Pp. 541-9.

CENTRAL SLEEP APNEA.  T.D. Bradley; Clin Chest Med (Sept 1992; 13(3)).  Pp.
493-505.

MANAGEMENT OF OBSTRUCTIVE SLEEP APNEA.  M.H. Kryger; Ckin Chest Med (Sept
1992; 13(3)).  Pp. 481-492.

THE OCCURRENCE OF SLEEP-DISORDERED BREATHING AMONG MIDDLE-AGED ADULTS.
T. Young, Ph.D., et al.; The New England Journal of Medicine (April 29, 1993,
issue 328 (17)).  Pp. 1230-35.