What is narcolepsy?
Narcolepsy is a sleep disorder that affects around 200,000 Americans. Patients suffer from excessive sleepiness through the day. They often require naps through the day to be functional. It can greatly impact their daily routine and can make it difficult to perform simple tasks.
Narcolepsy is divided into two types:
- Narcolepsy Type 1 – includes sudden onset muscle weakness (called cataplexy) in response to being startled, scared, or an emotional high or low. In rare cases the whole body is affected and patients “pass out.” In the majority of cases on a smaller muscle group is involved (like the hand or jaw or thigh) and consciousness is maintained.
- Narcolepsy Type 2 – does not include cataplexy and makes up the majority of diagnoses
What causes narcolepsy?
The cause of narcolepsy isn’t fully understood. However, there are some patients who clearly lack a brain hormone (orexin/hypocretin) that is responsible for maintaining wakefulness in the brain. It is likely that early childhood infections, such as “mono,” can lead to autoimmune process where the parts of the brain responsible for orexin is damaged. There are known genetic mutations that can predispose patients to narcolepsy as well.
While rare, narcolepsy, and other disorders of excessive sleepiness, can also develop after an injury to certain parts of your brain. This can result from concussions, strokes, brain tumors, or traumatic brain injuries..
What are the symptoms of narcolepsy?
The most obvious symptom of narcolepsy is the excessive daytime sleepiness and a struggle to stay awake during the day. Patients with narcolepsy often find naps to be helpful, refreshing. Other common symptoms include:
- Muscle weakness (cataplexy)
- Hallucinations going to sleep or while waking
- Sleep paralysis
- Inability to move after waking
- Fragmented sleep at night
- Amnesia
- Outbursts during sleep
- Body movements while sleeping.
How is narcolepsy diagnosed?
Narcolepsy is diagnosed in one of two ways.
An overnight and the all-day sleep study called a “mean sleep latency test” (MSLT). Sleep duration and sleep structure is monitored overnight and then patients are allowed to take naps the next day at 2 hr intervals (8am, 10am, noon, etc). This study looks for if the patient can nap each time, how quickly they fall asleep, and what stages of sleep they experience during the nap.
A spinal tap or lumbar puncture measures the orexin hormone levels in your spinal fluid. Unfortunately, not every patient with narcolepsy would have a low orexin level in their spinal fluid, but this test can be helpful for making the diagnosis if the MSLT cannot be performed.
What are treatment options for narcolepsy?
Although there is no cure for narcolepsy, there are ways you can manage your symptoms using medications like stimulants, SNRIs or SSRIs. Lifestyle changes, like developing a consistent sleep schedule, scheduling short naps at regular intervals during the day, and avoiding nicotine and alcohol can all help to manage your symptoms.