Chapter 028. Sleep Disorders (Part 7)

Psychophysiologic InsomniaPersistent psychophysiologic insomnia is a behavioral disorder in which patients are preoccupied with a perceived inability to sleep adequately at night. This sleep disorder begins like any other acute insomnia; however, the poor sleep habits and sleep-related anxiety ("insomnia phobia") persist long after the initial incident. Such patients become hyperaroused by their own efforts to sleep or by the sleep environment, and the insomnia becomes a conditioned or learned response. Patients may be able to fall asleep more easily at unscheduled times (when not trying) or outside the home environment. Polysomnographic recording in patients with psychophysiologic insomnia reveals...
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Chapter 028. Sleep Disorders (Part 7) Chapter 028. Sleep Disorders (Part 7) Psychophysiologic Insomnia Persistent psychophysiologic insomnia is a behavioral disorder in whichpatients are preoccupied with a perceived inability to sleep adequately at night.This sleep disorder begins like any other acute insomnia; however, the poor sleephabits and sleep-related anxiety (insomnia phobia) persist long after the initialincident. Such patients become hyperaroused by their own efforts to sleep or bythe sleep environment, and the insomnia becomes a conditioned or learnedresponse. Patients may be able to fall asleep more easily at unscheduled times(when not trying) or outside the home environment. Polysomnographic recordingin patients with psychophysiologic insomnia reveals an objective sleepdisturbance, often with an abnormally long sleep latency; frequent nocturnalawakenings; and an increased amount of stage 1 transitional sleep. Rigorousattention should be paid to improving sleep hygiene, correction ofcounterproductive, arousing behaviors before bedtime, and minimizingexaggerated beliefs regarding the negative consequences of insomnia. Behavioraltherapies are the treatment modality of choice, with intermittent use ofmedications. When patients are awake for >20 min, they should read or performother relaxing activities to distract themselves from insomnia-related anxiety. Inaddition, bedtime and wake time should be scheduled to restrict time in bed to beequal to their perceived total sleep time. This will generally produce sleepdeprivation, greater sleep drive, and, eventually, better sleep. Time in bed can thenbe gradually expanded. In addition, methods directed towards producingrelaxation in the sleep setting (e.g., meditation, muscle relaxation) are encouraged. Adjustment Insomnia (Acute Insomnia) This typically develops after a change in the sleeping environment (e.g., inan unfamiliar hotel or hospital bed) or before or after a significant life event, suchas a change of occupation, loss of a loved one, illness, or anxiety over a deadlineor examination. Increased sleep latency, frequent awakenings from sleep, andearly morning awakening can all occur. Recovery is generally rapid, usuallywithin a few weeks. Treatment is symptomatic, with intermittent use of hypnoticsand resolution of the underlying stress. Altitude insomnia describes a sleepdisturbance that is a common consequence of exposure to high altitude. Periodicbreathing of the Cheyne-Stokes type occurs during NREM sleep about half thetime at high altitude, with restoration of a regular breathing pattern during REMsleep. Both hypoxia and hypocapnia are thought to be involved in the developmentof periodic breathing. Frequent awakenings and poor quality sleep characterizealtitude insomnia, which is generally worse on the first few nights at high altitudebut may persist. Treatment with acetazolamide can decrease time spent in periodicbreathing and substantially reduce hypoxia during sleep. Comorbid Insomnia Insomnia Associated with Mental Disorders Approximately 80% of patients with psychiatric disorders describe sleepcomplaints. There is considerable heterogeneity, however, in the nature of thesleep disturbance both between conditions and among patients with the samecondition. Depression can be associated with sleep onset insomnia, sleep maintenanceinsomnia, or early morning wakefulness. However, hypersomnia occurs in somedepressed patients, especially adolescents and those with either bipolar or seasonal(fall/winter) depression (Chap. 386). Indeed, sleep disturbance is an importantvegetative sign of depression and may commence before any mood changes areperceived by the patient. Consistent polysomnographic findings in depression include decreasedREM sleep latency, lengthened first REM sleep episode, and shortened firstNREM sleep episode; however, these findings are not specific for depression, andthe extent of these changes varies with age and symptomatology. Depressedpatients also show decreased slow-wave sleep and reduced sleep continuity. In mania and hypomania, sleep latency is increased and total sleep time canbe reduced. Patients with anxiety disorders tend not to show the changes in REMsleep and slow-wave sleep seen in endogenously depressed patients. Chronicalcoholics lack slow-wave sleep, have decreased amounts of REM sleep (as anacute response to alcohol), and have frequent arousals throughout the night. This isassociated with impaired daytime alertness. The sleep of chronic alcoholics may remain disturbed for years afterdiscontinuance of alcohol usage. Sleep architecture and physiology are disturbedin schizophrenia (wit ...