Narcolepsy is a chronic condition characterised by a disruption of the sleep-wake cycle and rapid eye movement (REM) sleep intrusion.
The classic tetrad of narcolepsy, seen in only 10% to 15% of cases, includes excessive daytime sleepiness, cataplexy, sleep paralysis, and hypnagogic/hypnopompic hallucinations.
The only clinical manifestation that is specific to narcolepsy is cataplexy.
Disease onset is usually in the second decade of life.
Multiple sleep latency test usually shows shortened sleep latency and at least 2 sleep-onset REM periods.
Therapy involves lifestyle modification, stimulants for daytime sleepiness, and drug treatment for cataplexy.
Narcolepsy is a chronic sleep boundary disorder that affects the control of sleep and wakefulness with rapid eye movement sleep intrusion into the wake state. In its classic form, seen in only 10% to 15% of cases, it is characterised by a tetrad of excessive daytime sleepiness, cataplexy (generalised muscle weakness leading to partial or complete collapse), hypnagogic/hypnopompic hallucinations (visual or auditory perceptions on falling asleep or on awakening), and sleep paralysis.
History and exam
Key diagnostic factors
- presence of risk factors
- excessive daytime sleepiness
- hypnagogic/hypnopompic hallucinations
- sleep paralysis
Other diagnostic factors
- chronic fatigue or tiredness
- poor performance at work
- poor memory and concentration
- car accidents
- slurred speech
- blurred vision
- irregular breathing pattern
- sleep attacks
- fragmented nocturnal sleep
- symptoms of other sleep disorders
- status cataplecticus
- human leukocyte antigen (HLA)-II DQA1*0102-DQB1*0602
- Prader-Willi syndrome
- Niemann-Pick disease type C
- low cerebrospinal fluid hypocretin
- linkage to 4p13-q21
- genes on chromosome 6 or chromosome 21
- hypothalamic tumours
- hypothalamic infarct/haemorrhage
- head trauma
- central nervous system infection
- central nervous system arteriovenous malformations
- multiple sclerosis
1st investigations to order
- actigraphy and sleep diary
- overnight polysomnography
- multiple sleep latency test (MSLT)
Investigations to consider
- HLA typing
- cerebrospinal fluid hypocretin-1 level
- maintenance of wakefulness test
adults with excessive daytime sleepiness (EDS)
adults with cataplexy
children with excessive daytime sleepiness (EDS)
children with cataplexy
Octavian C. Ioachimescu, MD, PhD
Atlanta VA Medical Center
OCI is an editor of a book cited in this topic.
Kumaraswamy Budur, MD
Sleep Disorders Center
Department of Psychiatry
KB declares that he has no competing interests.
Seiji Nishino, MD, PhD
Psychiatry and Behavioral Science
Stanford University School of Medicine
SN declares that he has no competing interests.
Kingman P. Strohl, MD, FCCP
Professor of Medicine
Center for Sleep Disorders Research
Professor of Anatomy
Department of Medicine
Case Western Reserve University
KPS declares that he has no competing interests.
Paul Reading, MBBS
James Cook University Hospital
PR declares that he has no competing interests.
- Untreated sleep apnoea
- Periodic limb movements of sleep
- Restless legs syndrome (RLS)
- European guideline and expert statements on the management of narcolepsy in adults and children
- Treatment of central disorders of hypersomnolence
Sleep apnoea in adults (obstructive)
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