Home > Encyclopedia of Mental Disorders > Sleep disorders

Definition

Sleep disorders are chronic disturbances in the quantity or quality of sleep that interfere with a person's ability to function normally.

Description

An estimated 15% of Americans have chronic sleep problems, while about 10% have occasional trouble sleeping. Sleep disorders are listed among the clinical syndromes in Axis I of the American Psychiatric Association's Diagnostic and Statistical Manual of Mental Disorders, also known as the DSM. They may be either primary (unrelated to any other disorder-medical or psychological) or secondary (the result of physical illness, psychological disorders, or drug or alcohol use).

In the revised fourth edition of the DSM(DSM-IV-TR), the primary sleep disorders are categorized as either dyssomnias or...