Sleep disorders

• Causes, incidence, and risk factors

  More than 100 different disorders of sleeping and waking have been identified. They can be grouped in four main categories:

  • Problems with falling and staying asleep (insomnia)
  • Problems with staying awake (excessive daytime sleepiness)
  • Problems with sticking to a regular sleep schedule (sleep rhythm problem)
  • Unusual behavoirs during sleep (sleep-disruptive behaviors)

  PROBLEMS WITH FALLING AND STAYING ASLEEP

  Insomnia includes any combination of difficulty with falling asleep, staying asleep, intermittent wakefulness and early-morning awakening. Episodes may come and go (be transient), last as long as 2 to 3 weeks (be short-term), or be long-lasting (chronic).

  Common factors associated with insomnia include:

  • Physical illness
  • Depression
  • Anxiety or stress
  • Poor sleeping environment such as excessive noise or light
  • Caffeine
  • Alcohol or other drugs
  • Use of certain medications
  • Heavy smoking
  • Physical discomfort
  • Daytime napping
  • Counterproductive sleep habits:
    • Early bedtimes
    • Excessive time spent awake in bed

  Disorders include:

  • Psychophysiological insomnia: a condition in which stress caused by the insomnia makes it even harder to fall asleep
  • Delayed sleep phase syndrome: your internal clock is constantly out of synch with the "accepted" day / night phases; for example, patients feel best if they can sleep from 4AM to noon
  • Hypnotic-dependent sleep disorder: insomnia that occurs when you stop or become tolerant to certain types of sleep medications
  • Stimulant-dependent sleep disorder: insomnia that occurs when you stop or become dependent on certain types of stimulants

  PROBLEMS WITH STAYING AWAKE

  Disorders of excessive sleepiness are called hypersomnias. These include:

  • Idiopathic hypersomnia (excessive sleepiness that occurs without an identifiable cause)
  • Narcolepsy
  • Obstructive and central sleep apnea
  • Periodic limb movement disorder
  • Restless leg syndrome

  PROBLEMS STICKING TO A REGULAR SLEEP SCHEDULE

  Problems may also occur when you do not maintain a consistent sleep and wake schedule. This occurs when traveling between times zones and with shift workers on rotating schedules, particularly nighttime workers.

  Sleep disruption disorders include:

  • Irregular sleep-wake syndrome
  • Jet lag syndrome
  • Natural short sleeper (the person sleeps less hours than normal but has no ill effects)
  • Paradoxical insomnia (the person actually sleeps a different amount than they think they do)
  • Shift work sleep disorder

  SLEEP-DISRUPTIVE BEHAVIORS

  Abnormal behaviors during sleep are called parasomnias and are fairly common in children. They include:

  • Sleep terrors
  • Sleep walking
  • REM sleep-behavior disorder (a type of psychosis in which a person"acts out" dreams so violently that they may injure the person sleeping with them)
• Symptoms

  The symptoms vary and depend on the specific sleep disorder.

• Signs and tests

  Tests vary and depend on the specific sleep disorder. A sleep study (polysomnography) may be done.

• Treatment

  Treatments vary and depend on the specific sleep disorder.

  See:

  • Insomnia
  • Hypersomnias
  • Sleep terrors
  • Sleep walking
• Expectations (prognosis)

  The outcome varies with the type of disorder. Some disorders may go away without treatment.

• Calling your health care provider

  Call for an appointment with your health care provider if lack of sleep, too much sleep, or unusual sleep behaviors are interfering with daily living.

  Sleep apnea should be suspected in people who snore loudly, wake frequently to urinate at night, and wake up in the morning unrefreshed.

• Prevention

  The following can help prevent many sleep disorders.

  • Regular sleep habits (such as going to bed and waking at the same time every day)
  • A quiet sleep environment
  • Regular exercise
  • Staying generally fit and healthy

Review Date: 8/12/2009

Reviewed By: Allen J. Blaivas, DO, Pulmonary, Critical Care, and Sleep Medicine, Department of Veteran Affairs, VA New Jersey Health Care System, East Orange, NJ . Review provided by VeriMed Healthcare Network. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc.