Narcolepsy

What it is

Narcolepsy is an autoimmune disorder that leads to excessive daytime sleepiness and pressure to enter rapid eye movement (REM) sleep at inappropriate times, including while awake.

Misconceptions

  • Narcolepsy is extremely rare - FALSE (see “The Nuts & Bolts” below).

  • Narcolepsy is where you fall asleep in the middle of a conversation or activity - ONLY in extreme cases but this is NOT a requirement.

  • To have narcolepsy, you have to have all of the symptoms (sleepiness, cataplexy, sleep-related hallucinations, sleep paralysis, fragmented sleep) - FALSE! The ONLY requirement to consider narcolepsy is excessive daytime sleepiness.

The Nuts & Bolts

  • Narcolepsy can occur at any time in the lifespan, but the highest occurrences are in late childhood/teenage years (most common) or mid-thirties.

  • Narcolepsy prevalence in the United States is 1 out of every 2000 people (0.05%). This is the same as lupus (SLE) and similar to multiple sclerosis.

  • It can take 10 years and up to 7 different doctors from the time of symptoms onset to reach the diagnosis of narcolepsy.

The Symptoms

  • Excessive daytime sleepiness (EDS) - EDS is sleepiness above and beyond “normal” and not due to behavioral causes (e.g., not getting enough sleep because you go to bed too late). Sleepiness is subjective by nature, so tools are used to help decide what’s “abnormal.” The most widely used tool is the Epworth Sleepiness Scale. Scores above 10 out of 24 are considered EDS.

  • Cataplexy - An episode of cataplexy is a transient muscle weakness that is induced by an emotional stimulus. The “textbook” example is knee buckling that is caused by laughter. However, I find that this is only a fraction of the cataplexy I see. Cataplexy can be much more subtle: eyelid weakness, changes in speech, hand clumsiness, a general feeling of malaise/weakness, a sense of “melting,” and others. The emotional trigger doesn’t have to be laughter. It can be anger, frustration, surprise, or even situational (e.g., feeling stressed at work).

  • Hypnagogic hallucinations - These occur in a dream-like state right at the onset of sleep. The individual will see and hear dreams before fully losing consciousness. If awoken quickly after sleep onset, the individual may be unsure if the event was a dream or real.

  • Sleep paralysis - Episodes of sleep paralysis occur out of REM sleep. During the episode, the individual cannot move, with the exception of eye movements and breathing. These episodes typically are brief, occurring for a few seconds or a minute. They sometimes are associated with a visual hallucination, such as the silhouette of an individual or demon in the room.

  • Fragmented sleep - Fragmented sleep is a hallmark of many sleep disorders, but it is a common occurrence in narcolepsy. Sometimes, this means the individual will wake up frequently during the night. Other times, it just means that sleep is highly disjointed at the level of the brain, but the individual does not wake up.