What is Narcolepsy?

Narcolepsy is a neurological disease
• It is a chronic disease. During the first years after the onset of the first symptoms, there may be progression in severity of the existing symptoms and additional symptoms may develop. Progression of symptoms is unusual after 4-6 years.
• It is a rare disease affecting 20-40 out of 100,000 persons depending on the ethnic origin
• It is caused by an impaired hypocretin (or orexin) neurotransmission. It seems to be caused by the loss of a group of neurons (named hypocretins or orexins) in the midbrain (hypothalamus). Why these neurons disappear is not known. An autoimmune cause is suspected.
• The majority of cases are sporadic, about 5% are familial
• The relative risk of a narcolepsy offspring to inherit narcoleptic symptoms is 200??
• The onset can be at any age, but there is a clear bimodal distribution with peaks at age 15 and 36 years.
• The diagnosis is established according to the International Classification of Sleep Disorders (ICSD-2) developed in 2005, which requires the presence of either 3 months of excessive daytime sleepiness and/or the presence of clear cut cataplexy and in any case the diagnosis in a sleep laboratory with polysomnography and multiple sleep latency test (MSLT)
• Biologic markers are the presence of HLA DQB1*06:02 and low hypocretin-1 in the cerebrospinal fluid (below 110pg/ml).
• So far narcolepsy can not be cured
• There is efficacious treatment