Definition: Conditions characterized by disturbances of usual sleep patterns or behaviors. Sleep disorders may be divided into three major categories: DYSSOMNIAS (i.e. disorders characterized by insomnia or hypersomnia), PARASOMNIAS (abnormal sleep behaviors), and sleep disorders secondary to medical or psychiatric disorders. (From Thorpy, Sleep Disorders Medicine, 1994, p187)
Synonyms (terms occurring on more labels are shown first): sleep disorder, sleep disorders, sle ep disorder, Sleep disorders and disturbances, s leep disorder
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