Narcolepsy, also known as sleeping sickness, is a rare disorder that has different types and degrees of symptoms. It causes people to fall asleep unexpectedly and affects about 0.1% of the world’s population.
The term narcolepsy was coined by Jean-Baptiste-Édouard Gélineau in the late 19th century. This scientist was the first to describe it in 1880. He gave it its name based on two Greek words, narcotics and lepsi, which together mean “numbness attack”.
What is narcolepsy?
Narcolepsy is a chronic neurological disorder that causes sleep arrhythmias. Its main symptom is severe drowsiness during the day and sudden sleep attacks that can not be stopped.
Those with any type or degree of narcolepsy have great difficulty staying awake for several hours, regardless of the circumstances in which they find themselves. For this reason , it significantly affects their quality of life.
In some cases, this disorder appears with a sudden relaxation of the muscles which in medical terms is defined as cataplexy. This can occur due to an intense feeling, and how it is expressed will define the type and degree of narcolepsy.
This disease has no cure and there is no specific treatment as such. However, some medications help control these sudden sleep attacks. Similarly , lifestyle changes can be helpful, as well as social and psychological support.
Characteristics of the disease
Here are the main characteristics of narcolepsy:
- Excessive daytime sleepiness. A reduction in alertness and concentration. This is usually the first symptom that manifests itself, and then the sudden desire to sleep.
- Cataplexy. As we mentioned above, it does not appear in all cases, nor with the same intensity.
- Sleep paralysis. This is a temporary inability to move or talk. This is especially true when a person falls asleep or wakes up. They are usually short episodes.
- Changes in REM sleep. REM sleep is the deepest. During it, there are usually rapid eye movements. A person with narcolepsy can enter this stage at any time.
- Hallucinations. They are called hypnagogic hallucinations if they occur before the person falls asleep or hypnopumpic hallucinations if they occur when they wake up. They can be very lively and scary.
People with narcolepsy can also suffer from other sleep disorders, such as obstructive sleep apnea, sleep fragmentation and restless legs syndrome (RLS). Although paradoxical, they can also suffer from insomnia.
Types and degrees of narcolepsy
According to the criteria of the DSM-5 (the fifth version of the Diagnostic and Statistical Manual of Mental Disorders), there are five types and degrees of narcolepsy, which are as follows:
- Without cataplexy and with hypocretin deficiency. In this type of narcolepsy, there is a deficiency of the hormone orexin or hypocretin. This is a protein that affects neuronal function. The main function of this protein is to control the sleep-wake cycle. This type does not cause cataplexy episodes.
- With cataplexy and without hypocretin deficiency. In this case, there is no hypocretin deficiency, but there is cataplexy. This is a sudden muscle weakness on both sides of the body. It is the least understood symptom of this disorder and affects 5% of all cases.
- Autosomal dominant cerebellar ataxia (ADCA), deafness and narcolepsy. This degree of narcolepsy is caused by a DNA mutation. Ataxia is a lack of motor coordination that affects voluntary movements and even impedes functions such as swallowing, speech and vision. It comes late and often leads to dementia as it develops.
- Autosomal dominant cerebellar narcolepsy with ataxia, deafness, obesity and type 2 diabetes. This is due to a mutation in the oligodendrocytes, a class of cells that affect myelin formation. The latter is a substance that increases the speed of nerve transmission and a deficiency affects mobility.
- Secondary to another medical condition. One of the types of narcolepsy appears as a consequence of another disease. For example, sarcoidosis or Whipple’s disease. Both destroy cells that produce hypocretin.
All degrees of narcolepsy require medical attention
Although there is no cure for narcolepsy, there are several treatments available. They relieve most symptoms and allow the sufferer to live an almost normal life.
People suffering from this condition can also make lifestyle changes, such as taking scheduled naps to relieve sudden drowsiness. In the same way, they need to be careful about sleep hygiene. A person with narcolepsy needs psychological and social support.