What are the causes of narcolepsy?
It is now firmly established that narcolepsy type 1 is caused by deficiencies in hypocretin (orexin) signaling, most likely due to a selective loss of hypothalamic hypocretin-producing neurons.
The majority of patients (90% to 95%) with narcolepsy type 1 have undetectable or low levels in the CSF.
There is a strong human leukocyte antigen (HLA) association in narcolepsy—HLA DQB1∗0602—that has led to the hypothesis that there is an autoimmune mechanism that could potentially explain the selective destruction of the hypocretin-containing neurons in the hypothalamus.
However, this is not diagnostic of narcolepsy.