Habitually insuffi cient total nighttime sleep
results in EDS. Review of a sleep diary or sleep
history of affected patients usually reveals a
chronically shortened nighttime sleep period that
is either less than the patient’s premorbid baseline.
For children and adolescents, the sleep
period is substantially reduced than normal for
age. Daytime symptoms are those found in sleep
deprivation, and include sleepiness, irritability,
disturbed mood, and impaired school or work
performance. Symptoms remit with lengthening
of the nighttime sleep period, but transiently
longer sleep periods (for example, on weekends,
holidays, or vacations) often do not provide complete
relief.