Causes of narcolepsy
The causes remain unknown. A genetic component is known to exist, but the possibility that the cause is an autoimmune reaction is gaining increasing support.
Understanding narcolepsy
When sleep enters
your waking day.
Narcolepsy is a chronic disorder of sleep–wake regulation. It may cause excessive sleepiness and involuntary sleep episodes, even after a night of sleep.
Type 1 is associated with cataplexy and/or low hypocretin (orexin). Type 2 does not involve cataplexy. Distinguishing them requires a specialist assessment.
Characteristics
The main characteristic is excessive daytime sleepiness and a feeling of constant tiredness, with sudden, uncontrollable sleep attacks in any place and situation.
Types of narcolepsy
We must distinguish two types of narcolepsy: type 1 and type 2. Type 1 features an absence of hypocretin in the cerebrospinal fluid. Type 2 maintains hypocretin levels and does not involve cataplexy.
Five manifestations to understand
Sleepiness is the core symptom. Other manifestations vary, and their absence does not rule out narcolepsy. A single symptom is not enough to establish a diagnosis.
Daytime sleepiness
A difficult-to-control need to sleep and involuntary sleep episodes. These can affect education, work and daily activities.
Cataplexy
Brief muscle weakness triggered by laughter or another emotion: knees may buckle, the head may drop or the jaw may slacken, without losing consciousness.
Sleep paralysis
When waking up or falling asleep, a person may be aware but temporarily unable to move. This can also occur without narcolepsy.
Sleep-related hallucinations
Vivid images, sounds or sensations may occur when falling asleep or waking up. On their own, these do not mean a psychiatric disorder.
Fragmented night-time sleep
Despite marked daytime sleepiness, nights may include repeated awakenings. Falling asleep easily by day does not necessarily mean sleeping well at night.