Causes and Risks:

More than 100 different disorders of sleeping and waking have been identified. They can be grouped within 4 main categories: problems with staying and falling asleep, problems with staying awake, problems with adhereing to a regular sleep schedule, and sleep disruptive behaviors.

PROBLEMS WITH STAYING AND FALLING ASLEEP
Insomnia includes any combination of difficulty with falling asleep, staying asleep, intermittent wakefulness, and early-morning awakening. Episodes may be transient, short-term (lasting 2 to 3 weeks), or chronic.

Illness, depression, anxiety, stress, poor sleeping environment (e.g., noise or too much light), caffeine, abuse of alcohol, medications, heavy smoking, physical discomfort, daytime napping, certain medical conditions, and other counterproductive sleep habits such as early bedtimes, and excessive time spent awake in bed are common factors associated with insomnia.

Disorders include:

• Psychophysiological (learned insomnia)
• Delayed sleep phase syndrome
• Hypnotic dependent sleep disorder
• Stimulant dependent sleep disorder

• Sleep apnea
• Narcolepsy
• Restless leg syndrome
• Obstructive sleep apnea
• Central sleep apnea
• Idiopathic hypersomnia
• Respiratory muscle weakness associated sleep disorder

Sleep apnea more commonly affects obese, people but it may affect others with short necks or a small jaw. The disorder causes breathing to stop intermittently during sleep resulting in people being awakened repeatedly such that they have difficulty achieveing prolonged deep sleep and results in excessive daytime sleepiness.

Narcolepsy is a condition of daytime sleep attacks as well as other features which may include sleep paralysis and hypnogogic hallucinations. Sleep attacks occur despite adequate sleep at night.

Restless leg syndrome is a condition of periodic lower-leg movements during sleep with associated daytime sleepiness, or complaints of insomnia.

PROBLEMS WITH ADHERING TO A REGULAR SLEEP SCHEDULE
Problems may also occur with maintaining a consistent sleep and wake schedule as a result of disruptions of normal times of sleeping and wakefulness. This occurs when traveling between times zones and with shift workers on rotating schedules, particularly with nighttime workers.

These disorders include:

• Sleep state misperception (the person actually sleeps a different amount than they think they do)
• Shift work sleep disorder
• Natural short sleeper (the person sleeps less hours than "normal" but suffers no ill effects)
• Chronic time zone change syndrome
• Irregular sleep-wake syndrome

• Sleep terror disorder
• Sleep walking
• REM behavior disorder (a type of psychosis can develop related to lack of REM sleep and lack of dreaming)

Sleep terror disorder is an abrupt awakening from sleep with fear, sweating, rapid heart rate, and confusion. Sleep walking is not remembered by the person doing it and affects children 2 to 12 years old.

In adults, it may also be caused by an organic brain syndrome, reactions to drugs, psychopathology and medical conditions.

Prevention: Maintaining regular sleep habits and a quiet sleep environment may prevent some sleep disorders.

Symptoms:

• Awakening in the night
• Difficulty falling asleep
• Excessive daytime drowsiness
• Loud snoring
• Episodes of stopped breathing
• Sleep attacks during the day
• Daytime fatigue
• Depressed mood
• Anxiety
• Difficulty concentrating
• Apathy
• Irritability
• Loss of memory (or complaints of decreased memory)
• Lower leg movements during sleep

Signs and Tests:

• Multiple sleep latency test
• Polysomnography

Treatment: Insomnia - The treatment is related to the cause, if it is determined. If there is an obvious physical or psychological cause, it is treated. Attempts to control environmental and lifestyle factors such as too much light, noise, caffeine or other stimulants, or erratic hours of wakefulness should be made. Sleeping drugs should be used only when prescribed by a health care provider.

Hypersomnia - Sleep apnea is treated with weight reduction and the administration of air under pressure through the nose. Occasionally, surgery or other measures may be needed. Narcolepsy is treated with stimulating medications during the daytime. Restless leg syndrome is treated by treating the underlying disorder and with opiate or dopaminergic agonists.

Parasomnias - Night terrors are treated with hypnosis, guided imagery techniques and benzodiazepines, but safety measures are needed to prevent people from harm during nighttime walking.

Sleep disorder clinics often are able to help people restore normal sleeping patterns through various techniques.

Prognosis: The outcome varies with the type of disorder; some disorders may resolve spontaneously.

Complications: A complication is dependence upon sedatives or other medications prescribed for sleep disorders.

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

Also call if breath-holding spells are observed during sleep.