Narcolepsy: the reason for microsleeps and with what symptoms it manifests itself

The term narcolepsy comes from narco (drowsiness) and lepsia (seizure/crisis). It describes a state characterized by episodes of sleep of short duration, occurring in short intervals of time. It is a syndrome of unknown origin and involves REM sleep dysfunction, in that this important phase of sleep appears at the inappropriate time, either at onset or after a nocturnal awakening.

Frequency of narcolepsy and what causes it

Narcolepsy occurs in 2 to 7 persons out of 10,000, affecting more males than females. The age of onset varies, ranging from preadolescence to 50-60 years of age. Typically, most patients develop their first symptoms before the age of 35.
It is a chronic pathology, that is to say, the patient will suffer from it all his life, but the causes are unknown. Recent studies suggest that it may have a neurochemical basis, involving the monoaminergic system. However, the absence of symptoms over time can lead to confusion in the diagnosis. Thus, when there are attacks of cataplexy during the sleep crisis the diagnosis by the specialist in Clinical Neurophysiology and Sleep Medicine is easy but sometimes more than 10 years can pass without a proper diagnosis. This happens because the symptoms do not occur at the same time: usually the sleep crisis occurs first and, years later, cataplexy.
What is noteworthy is the fact that in about half of the cases, there is some situation of stress or schedule changes and lack of sleep that triggers the symptoms. Likewise, there is also a predisposing genetic factor in half of the patients. In the other half of the patients, on the other hand, there will be no history of narcolepsy.

Clinical symptoms alerting to narcolepsy and consequences for the patient

There are a number of symptoms that alert the patient to the possibility of narcolepsy. Basic symptoms include excessive daytime sleepiness and cataplexy. Sleep paralysis and hypnagogic hallucinations are also considered auxiliary symptoms.
– Excessive daytime sleepiness: Unexpectedly, and without being able to control it, patients feel the need to sleep for a short period of time. When it occurs in preadolescents, parents usually notice learning delays, lack of attention and little interest in the environment. On the other hand, when it occurs in adults, they fall asleep at family gatherings, at work and even while driving. The problem is that these patients are misunderstood by their families, who reproach them for the fact that they are always so sleepy. At first the patients usually blame it on the fact that they are more tired, but they become more distressed because, no matter how much they want to, they are unable to control their sleep. These episodes can last from minutes to an hour, depending on the patient’s position. Thus, if he/she is lying down, he/she will fall asleep quickly. If, on the other hand, he tries not to fall asleep (because he is unable to do so at that moment), the drowsiness will persist until he can sleep for a few minutes. After this brief sleep, the patient feels comforted and active.
– Cataplexy: This is the sudden loss of muscle tone when the patient is awake, triggered by something emotional (joy, fear, surprise…). It can affect the entire musculature or only a part of it and last between seconds or even half an hour. If the cataplexy is partial, it usually affects the cervical and facial muscles, accompanied by irregular breathing. This prevents them from speaking for a few seconds, but may go unnoticed. However, cataplexy can also affect muscles of the trunk and arms, preventing precise movements. This generates great frustration in narcoleptic patients. If the muscles are totally affected, the person may even fall to the ground and suffer fractures and blows, sometimes mistaken for epileptic seizures. Cataplexy may occur daily or may be spaced out over time, although when it does occur, it is usually stable for a period of time. They are usually episodes lasting seconds, without loss of consciousness. It is the second symptom presented by patients and usually appears 3-4 years after the first sleep attack.
– Sleep paralysis: It is a phenomenon not at all pleasant for the patient. It occurs when sleep begins or ends. It consists of the impossibility to move the body, to speak and even to breathe deeply, in spite of being awake. There is a sensation of total immobility even if one tries with all one’s strength. It usually lasts a few seconds or minutes and disappears abruptly, so that the patient may even fall out of bed, when the strength reappears uncontrollably. The episodes are very frightening for the patient, creating anxiety and fear. If a person sees the patients from the outside, it looks as if they are sleeping. The problem lies in the fact that he/she cannot warn the other people in any way, so that they can help to stop the paralysis. A sleep study shows that the patient wakes up from a REM phase and the brain is fully awake but his/her muscle strength still remains in the REM phase (with atonia). It is a phenomenon that affects narcoleptic and non-narcoleptic patients, especially adolescents and young adults.
– Hypnagogic hallucinations: These are dreams that occur at the moment of falling asleep, although they can also occur upon awakening (then they are called hypnapompic). The dreams are usually intense visual components, disproportionate to reality, without coherence. Some patients claim that they “see themselves from the outside” and may even incorporate sensory, olfactory and auditory components.