Fast Five Quiz: Narcolepsy

Heidi Moawad, MD


February 06, 2023

Type 1 narcolepsy is defined by low CSF HCRT-1, caused by the selective loss of hypothalamic neurons producing hypocretins. While the pathophysiology of type 2 narcolepsy is yet unknown, this phenotype is associated with normal levels of CSF HCRT-1.

Type 1 narcolepsy is strongly associated with the human leukocyte antigen (HLA) DQB1*0602 allele and other genetic features strongly suggesting a specific configuration of the immune system. Environmental triggers, such as upper airway infections, may prompt the destruction of hypothalamic hypocretin-producing neurons. In addition, head injury or brain tumors can cause damage to the area of the brain responsible for hypocretin production, leading to secondary narcolepsy.

Psychiatric comorbidities can complicate the diagnosis of narcolepsy. Mood disorders such as depression and anxiety are common in patients with narcolepsy, but it is unclear whether symptoms such as depression and anxiety are a result of the burden of the disease, or if in fact a shared pathophysiology exists.

Narcolepsy also has an established hereditary component.

Learn more about the pathophysiology of narcolepsy.


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