Narcolepsy is a chronic disorder characterized by excessive daytime sleepiness.
The cause is a deficiency of the neuropeptide orexin ( hypocretin ) that regulates wakefulness. Narcolepsy negatively affects all aspects of patients’ lives. The global prevalence is 25 to 50 per 100,000 people, with typical onset during adolescence, although a second peak may occur between ages 30 and 39.
Cataplexy can occur in people with narcolepsy and is often misdiagnosed.
Cataplexy is a phenomenon during wakefulness, characterized by a brief and sudden loss of muscle tone, often focused on the face or hands, without loss of consciousness ; The episodes are triggered by emotion. Narcolepsy type 1 often includes: excessive daytime sleepiness, cataplexy, sleep paralysis, hallucinations upon falling asleep, and fragmented sleep .
All symptoms may be present and cataplexy is absent in narcolepsy type 2 . Symptoms may be vague and may cause poor school or work performance, relationship difficulties, and worsening mood. Although short naps are refreshing, excessive sleepiness reappears after several hours.
People with suspected narcolepsy should be referred to a doctor specializing in sleep medicine.
Referral thresholds include symptoms that persist for more than 3 months or any episode of cataplexy. The symptoms should not be better explained by another sleep disorder, medication or substance use, or a mood disorder.
Multiple sleep latency testing (MSLT) is the first-line diagnostic test
Diagnostic tests for narcolepsy include an overnight polysomnography followed by a multiple sleep latency test (MSLT) the next day, which determines whether the patient has an abnormal propensity to fall asleep and enter rapid eye movement (REM) sleep. ). The MSLT consists of providing 5 monitored daytime nap opportunities, scheduled 2 hours apart.
Treatment is lifelong and requires adjustments based on fluctuations in disease severity.
Treatment includes optimizing nap and sleep hygiene; patient and family education; and medications that promote wakefulness, consolidate sleep, and suppress cataplexy. With treatment, many people with narcolepsy can regain near-normal function; They may be eligible to drive once symptoms have been controlled for 12 months.
