Sleep-Wake Disorders Clinical Presentation

Updated: Aug 21, 2019
  • Author: Roy H Lubit, MD, PhD; Chief Editor: Ana Hategan, MD, FRCPC  more...
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Insomnia may present as decreased sleep efficiency or decreased total hours of sleep, with some associated decrease in productivity or well-being. Because sleep requirements vary from person to person, the quality of sleep is more important than the total number of hours slept. The total number of hours slept should be compared with each individual’s lifelong normal night sleep time.

Initial insomnia (also referred to as early insomnia or sleep-onset insomnia) is characterized by difficulty in falling asleep, with an increase in sleep latency (ie, the time between going to bed and falling asleep). Initial insomnia is frequently related to anxiety disorders.

Middle insomnia (also referred to as sleep-maintenance insomnia) refers to difficulty in maintaining sleep. Decreased sleep efficiency is present, with fragmented unrestful sleep and frequent waking during the night. Middle insomnia may be associated with medical illness, pain syndromes, or depression.

In terminal insomnia (also referred to as late insomnia or early morning wakening insomnia), patients consistently wake up earlier than needed. This symptom is frequently associated with major depression.

Alterations of the sleep-wake cycle may be a sign of circadian rhythm disturbances, such as those caused by jet lag and shift work.

Hypersomnia, or excessive daytime sleepiness, is often attributable to ongoing sleep deprivation or poor-quality sleep arising from causes ranging from sleep apnea to substance abuse or medical problems.

In delayed sleep phase syndrome, the patient is unable to fall asleep until very early morning. As time progresses, the onset of sleep becomes progressively delayed.

Sleepwalking, also called somnambulism, refers to episodes of complex behaviors occurring during non–rapid eye movement (NREM) sleep (stages 3 and 4), of which the patient is amnestic afterward.

Nightmares are repeated awakenings from sleep caused by vivid and distressing recall of dreams. Nightmares usually occur during the second half of the sleep period. Upon wakening from the dream, the person rapidly reorients to time and place.

Night terrors are recurrent episodes of abrupt awakening from sleep characterized by a panicky scream, with intense fear and autonomic arousal. The individual usually has no recall of the details of the event and is unresponsive during the episode. Night terrors occur during the first third of the night, during stages 3 and 4 of NREM sleep.

Sleep paralysis occurs when an individual begins waking up while still in REM sleep and is therefore paralyzed. Individuals can have hallucinatory and paranoid experiences. [5]

Bed partners of patients who snore may provide a history of snoring. Such a history may help determine whether a patient experiences obstructive sleep apnea (OSA).


Physical Examination

Signs of sleep disorders include the following:

  • Hypertension (which can be caused by sleep apnea)

  • Disturbed coordination (which can be caused by sleep deprivation)

  • Drowsiness

  • Poor concentration

  • Slowed reaction time

  • Weight gain



Sleep apnea is potentially very serious. In addition to loss of sleep it can have adverse cognitive effects, can damage the brain, and can damage the cardiovascular system. Two thirds of people with sleep apnea are depressed. [6]

Mood and anxiety disorders may develop from untreated sleep disturbances, and current medical literature supports the theory that these brain-based mental status changes are risk factors for morbidity and mortality from a host of medical conditions (eg, cardiovascular disease). [7]

Caution is advised in the treatment of patients who are elderly and others who may be at increased risk for falls.