Melissa Conrad Stöppler, MD, is a U.S. board-certified Anatomic Pathologist with subspecialty training in the fields of Experimental and Molecular Pathology. Dr. Stöppler's educational background includes a BA with Highest Distinction from the University of Virginia and an MD from the University of North Carolina. She completed residency training in Anatomic Pathology at Georgetown University followed by subspecialty fellowship training in molecular diagnostics and experimental pathology.
Dr. Charles "Pat" Davis, MD, PhD, is a board certified Emergency Medicine doctor who currently practices as a consultant and staff member for hospitals. He has a PhD in Microbiology (UT at Austin), and the MD (Univ. Texas Medical Branch, Galveston). He is a Clinical Professor (retired) in the Division of Emergency Medicine, UT Health Science Center at San Antonio, and has been the Chief of Emergency Medicine at UT Medical Branch and at UTHSCSA with over 250 publications.
Sleep disorders are disruptions of the sleep cycle or the quality of sleep.
About 40 million Americans are believed to suffer from chronic sleep disorders,
with millions more affected on an occasional basis. Doctors have defined over 70
different types of sleep disorders, but the most common sleep disorders are
insomnia, sleep apnea, restless legs syndrome, and narcolepsy.
Insomnia is the perception of poor-quality sleep, including the inability
to fall asleep or stay asleep. Because people differ in their need for sleep,
there are no fixed criteria that define insomnia. Insomnia is very common and
occurs in 30% to 50% of the general population. Approximately 10% of the
population may suffer from chronic (long-standing) insomnia.
Sleep apnea is another common sleep disorder characterized by a reduction
or pause of breathing (airflow) during sleep. Central sleep apnea (CSA) occurs
when the brain does not send the signal to the muscles to take a breath, and
there is no muscular effort to take a breath. Obstructive sleep apnea (OSA)
occurs when the brain sends the signal to the muscles and the muscles make an
effort to take a breath, but they are unsuccessful because the airway becomes
obstructed and prevents an adequate flow of air. Mixed sleep apnea occurs when
there is both central sleep apnea and obstructive sleep apnea.
Restless leg syndrome (RLS), also known as nocturnal myoclonus, is a type
of sleep disorder characterized by uncomfortable sensations in the legs and an
uncontrollable desire to move the legs. These abnormal sensations usually occur
in the lower legs shortly after going to bed. During the early stages of sleep,
these episodes of leg movement often last up to an hour. The abnormal sensations
of RLS are quite variable. They have been described as a crawling, creeping,
pulling, drawing, tingling, pins and needles, or prickly discomfort. They are
not cramping in character.
Narcolepsy is a disease of the central nervous system that results
uniformly in excessive daytime sleepiness (EDS). Other primary symptoms of
narcolepsy include the loss of muscle tone (cataplexy), distorted perceptions
(hypnagogic hallucinations), and the inability to move or talk (sleep paralysis). Additional symptoms can include disturbed nocturnal sleep and
automatic behaviors (affected persons carry out certain actions without
conscious awareness). All of the symptoms of narcolepsy may be present in
various combinations and degrees of severity.