|
Parasomnias
Last edited |
10/22/2008
Written by Maurice M. Ohayon, MD, DSc, PhD
Parasomnias are a heterogeneous group of sleep disorders that are not strictly
speaking abnormalities or dysfunctions of the processes underlying sleep-wake
states
The American Classification of mental disorders (DSM-IV,
American Psychiatric Association) recognizes only three parasomnias:
-
Nightmares,
-
Night terrors
-
and Sleepwalking.
There are, however, several other parasomnias identified in
the International Classification of Sleep Disorders, for example:
Most of these
disorders are relatively frequent and benign in children and adolescents and
disappear in early adulthood.
The presence of some of these disorders in adults, such as
night terrors,
nightmares, or
confusional arousals
may be indicative of a more severe disorder.
Night Terrors Adults with
night terrors exhibit a high level of anxiety,
depression, obsessive-compulsive and phobic traits on personality questionnaires
such as the MMPI.
Furthermore, mental stress and specific life events have been
reported to trigger or increase the frequency of night terror and sleepwalking
episodes.
Nightmares Nightmares in adults are associated with various psychiatric disorders
(1).
Continuous recurrent nightmares positively response to antidepressant
medications in depressed individuals.
Nightmares are also frequently observed in
schizophrenic patients and acute schizophrenic episodes are often preceded of a
period of frequent nightmares.
Individuals with a posttraumatic stress disorder
may also experience recurrent nightmares about the traumatic event.
The common
association of sleep and eating abnormalities in patients with former sexual
abuse (and other traumas) leads to many misdiagnoses in general practice (and in
specialist sleep clinics).
Confusional
Arousals
Confusional
arousals appear to occur quite frequently in the general population, affecting
mostly younger subjects regardless of their gender.
The association between confusional arousals, mental disorders and OSAS
is frequent.
Furthermore, the high occurrence of confusional arousals in shift or night
workers may increase the likelihood of inappropriate response by employees
sleeping at work.
Violent
Behaviors Recent studies in the general population have shown that
violent
behaviors during sleep are not so rare:
Sleep
Paralysis
Sleep paralysis
is a transient and generalized inability
to move and speak that occur during the transitional period between sleep and
wakefulness.
Episodes vary from one to several minutes and are usually extremely
distressing especially when they are accompanied with
hypnagogic or hypnopompic
hallucinations.
Sleep paralysis occurs in 30 to 60% of narcoleptic patients.
Epidemiological studies shown that 6.2% of the general population experienced at
least one such episode in their lifetime.
Moreover, sleep paralysis is often
associated with a mental disorder. In some cases, anxiolytic medication may be
responsible for this manifestation (3).
Other parasomnias Other parasomnias are
interesting because they cause fear to individuals presenting with them. They are also interesting because they are not well-known by the physicians.
|
Sleep-EVAL
Research
