Shrouded in secrets and delusions, the disease narcolepsy is relatively rare, but, most likely, each of us at least once met a person with such a pathology, without even knowing about it. The prevalence of the disease varies in different countries of the world and is on average estimated at 0.03–0.16%. So, for example, in Japan the indicator is 1 per 600 people, in America – 0.5-1 per 1000 inhabitants, in Israel – 1 per 500 thousand. Unfortunately, there is no exact data on the prevalence of the disease in Ukraine and the CIS countries due to insufficient knowledge disease.
What is narcolepsy and how is it different from simple sleepiness or fatigue? Why is the disease dangerous? How to deal with narcolepsy?
What is Narcolepsy?
Narcolepsy is a chronic neurological disorder that affects the brain’s ability to maintain wakefulness and sleep. It is relatively rare and often underestimated and confused with other sleep disorders.
Narcolepsy is manifested by unexpected and uncontrolled sleep attacks during the day. Such people may suddenly fall asleep even when they are engaged in certain activities. This is due to an unusually rapid transition from wakefulness to deep sleep, skipping the earlier stages of falling asleep. This situation leads to sudden falling asleep and the intrusion of dreams into reality. Most patients find it difficult to lead a normal life and maintain a daily routine.
Today, narcolepsy is considered incurable and lasts a lifetime.
The disease is usually diagnosed in adolescents and young people under 30 years of age. The prevalence among men and women is the same.
Narcolepsy is difficult to diagnose and can sometimes take decades from the onset to the diagnosis. About 50% of adults with narcolepsy retrospectively report this phenomenon and confirm that they have suffered from it since adolescence.
Uncontrolled bouts of sleepiness during the day is the main and most severe symptom of this disease. People with narcolepsy can suddenly fall asleep while eating, talking or driving without warning signs. It should be noted that the duration of sleep of patients per day is not necessarily high in comparison with healthy people.
The main symptoms of narcolepsy are:
- Daytime sleepiness;
- Cataplexy (decreased muscle tone);
- Hypnotic hallucinations;
- Vivid dreams;
- Sleep paralysis;
- Restless night sleep;
- Increased excitability;
- Tiredness during the day;
- Memory impairment.
These symptoms can vary in severity at different times in life, but never go away completely. They usually tend to deteriorate gradually over time and then stabilize. In other cases, the manifestations of the disease may diminish or even disappear for a while.
Cataplexy for narcolepsy
Cataplexy in its classic form is characterized by a sudden symmetrical loss of muscle tone without changing the state of consciousness. This state can arise as a result of emotional impressions, especially during laughter, anger, surprises and other vivid experiences. During a cataplexic attack, all muscles can be involved except for the muscles of the eyeball and the diaphragm. Muscle weakness can be complete or partial. Partial loss of tone is especially felt in the knees, leading to limp or wadded feet. Weakening of the muscles of the face manifests itself in the lowering of the lower jaw and problems with speech, and the muscles of the neck – in a sharp lowering of the head. A cataplexic attack begins suddenly, peaks within a few seconds, and ends after a few seconds or a few minutes. Sometimes during an attack there is a feeling of shortness of breath.
Cataplexy can appear as a symptom simultaneously with the onset of pathological drowsiness or several months or years after.
According to the International Classification of Sleep Disorders of the third revision (2014), narcolepsy of the first type (with cataplexy) and narcolepsy of the second type (without cataplexy) are distinguished.
Hypnotic hallucinations are dream-like states that occur during the transitional phase between wakefulness and sleep. If a similar phenomenon occurs during the transition from sleep to wakefulness, then it is called hypnopompic hallucinations. In most patients, the content of the hallucinations is strange, frightening, and rarely pleasant. These are usually visual hallucinations, although auditory and sensory hallucinations are also described .
Complete muscle paralysis during the falling asleep or waking phase, a phenomenon known as sleep paralysis, is another symptom of narcolepsy. Sleep paralysis is very similar to cataplexy, but is not associated with an emotional trigger and lasts longer. A person cannot move for several minutes. The attack, especially the first, is often very disturbing, especially when accompanied by hallucinations. Touching the patient brings him out of this state. The incidence of sleep paralysis in the general population, regardless of narcolepsy, is quite high, ranging from 5% to 62%.
The typical narcoleptic patient’s sleep at night is characterized by periodic awakenings and restlessness. Despite this, no clear relationship was found between sleep quality at night and the severity of sleepiness during the day. The direct cause of repetitive nocturnal awakenings is usually not found, however, patients report a high incidence of primary sleep disorders such as sleep apnea, restless legs syndrome , and others.
Adults with narcolepsy can be mistaken for lazy, inattentive, or generally disabled. They are often accused of using drugs or alcohol. At least 24% of people lose their jobs as a result of this disease.
Children with falling asleep problems may be the target of peer ridicule. They are often mistakenly diagnosed with attention deficit hyperactivity disorder (ADHD).
Causes of Narcolepsy
Some evidence suggests that narcolepsy begins as an autoimmune disorder that is most likely inherited. Certain infections (such as the H1N1 flu) can trigger an immune response at a young age. For reasons we don’t understand, the immune system overreacts to infection and attacks the neurons in the hypothalamus of the brain, which produce hypocretin ( orexin ), which the brain uses to maintain alertness. This results in the brain’s inability to regulate sleep and wakefulness. The decrease in hypocretin also affects the regular secretion of other key chemicals in the brain, such as dopamine, serotonin, and norepinephrine.
Narcolepsy has not yet been proven to be an autoimmune disease, but some facts support this theory:
- Detected certain infections in the brain, such as streptococcal infection;
- Cases have been observed after vaccination against swine flu;
- It is sometimes associated with other autoimmune diseases;
- There are few reports of the effectiveness of treatment with drugs that regulate the immune system.
Genetic and environmental factors may contribute to the onset of the disease, but these are not yet fully understood.
The diagnosis of narcolepsy is usually made very late and a common reason for this is low awareness among doctors. It can take decades from the first symptoms to be diagnosed.
The clinical diagnosis is clear in classical type 1 narcolepsy with characteristic cataplexic symptoms and is more difficult in type 2 narcolepsy. There are special diagnostic methods, in addition to collecting patient complaints and neurological examination, to confirm the disease.
Polysomnography is a method of graphically recording sleep processes in a special laboratory. During sleep, the patient’s electrical activity is recorded using EEG, muscle tone, and eye movement.
Narcolepsy will be diagnosed if the following criteria are met:
- Repeated bouts of uncontrolled need for sleep, sudden drowsiness or drowsiness that recur several times during the same day. These attacks should occur at least three times a week for three months
- Presence of at least one of the following conditions: episodes of cataplexy or hypocreatine deficiency , rapid eye movements during sleep.
Multiple Sleep Latency Study
Special electrodes are placed on the patient’s head to register impulses. The person is asked to fall asleep in 20 minutes for 4-5 attempts. People with narcolepsy have dreams immediately after falling asleep – this is their characteristic feature.
CT and MRI
Computed tomography and magnetic resonance imaging of the head make it possible to study the structure of the brain layer by layer, to exclude damage to the areas of the hypothalamus and pituitary gland, which are responsible for the regulation of the sleep-wake cycle.
Narcolepsy treatment options
As stated above, narcolepsy cannot be cured, but medication and lifestyle changes can make the symptoms of the disease much easier. Treatment is regular and accompanies a person throughout his life.
To relieve excessive daytime sleepiness, doctors prescribe stimulants or wakefulness medications. Antidepressants (tricyclic antidepressants, selective serotonin reuptake inhibitors, selective norepinephrine reuptake inhibitors, and selective serotonin and norepinephrine reuptake inhibitors) are very effective in reducing REM sleep disorders such as cataplexy, hypnagogic paralysis, and hallucinations. However, daytime sleepiness and cataplexy are largely associated with not being able to sleep through the night. For these problems, doctors may use central nervous system depressants to stimulate nighttime sleep.
- Drugs that promote wakefulness
Daytime activity enhancers are prescribed primarily to relieve excessive daytime sleepiness. Although their exact mode of action is unknown, they have been shown to act in a different way than stimulants. However, these drugs do not help relieve other REM sleep disorders, cataplexy, hallucinations, insomnia, or sleep paralysis.
Stimulants such as armodafinil and modafinil help reduce daytime sleepiness by increasing brain activity. They alter chemicals throughout the nervous system to boost alertness and energy. The mechanism of action of modafinil is unclear, but it probably affects the alpha-adrenergic system, reduces the transmission of GABA, and is involved in the inhibition of dopamine reuptake. Modafinil has been shown to activate hypocreatinergic neurons. Armodafinil is a modafinil derivative and has a longer half-life than modafinil and similar efficacy.
When armodafinil and modafinil are ineffective, methylphenidate or amphetamine derivatives are sometimes used . For many years, patients have been treated with various amphetamine derivatives and especially methylphenidate , as well as dextroamphetamine , methamphetamine and pulloline . These drugs were quite effective in reducing daytime sleepiness, but the treatment was accompanied by various side effects – anxiety, irritability, tremors, heart rhythm disturbances, decreased appetite, insomnia, and even toxicity.
Antidepressants can help relieve the symptoms of REM sleep in narcolepsy (cataplexy, sleep paralysis, and hypnagogic hallucinations) and are often prescribed as second-line therapy. Abrupt discontinuation of SSRIs ( venlafaxine , fluoxetine) and tricyclic antidepressants (imipramine, clomipramine ) can lead to prolonged cataplectic attacks.
- Sodium oxybutyrate and other sedatives
Many daytime symptoms of narcolepsy are due to nocturnal insomnia, so sedatives such as benzodiazepines (clonazepam, diazepam, gidazepam , lorazepam ) are often used in treatment . However, patients with narcolepsy do not have trouble falling asleep, but have trouble staying asleep all night. For this reason, the first drug of choice for treating both daytime sleepiness and cataplexy is sodium oxybutyrate , a unique drug that provides uninterrupted sleep throughout the night. By increasing the duration and quality of nighttime sleep, sodium oxybutyrate can significantly reduce daytime sleepiness and cataplexy. This drug has been recognized for many years as an anesthetic and was first proposed as a possible treatment for narcolepsy in 1979, but it was not until 2002 that it received FDA approval as a drug for the treatment of cataplexic narcolepsy . However, this drug is associated with drug addiction and serious side effects.
All drugs for narcolepsy are strictly prescription drugs and must be taken under medical supervision.
Living well is the second important component in relieving the symptoms of narcolepsy. It includes compliance with the rules of maintaining sleep hygiene and control of their sleep behavior, dietary nutrition, psychological assistance.
- Sleep hygiene involves keeping a regular sleep schedule. Go to bed at the same time every night, turn off the lights and do not watch TV before bed. Relax before bed and avoid heavy meals, intense exercise, or stimulants like caffeine. Patients should avoid unplanned sleep during the day, stimulants or sleeping pills if possible. Maintaining organized and regular sleep can be very beneficial for patients.
- Scheduled daytime sleep . Schedule 2-3 sleep breaks throughout the day and stick to your schedule. Taking a nap can help improve alertness throughout the day.
- Sleep log. Keep a diary in which you note your daily sleep hours. The log can help identify possible behavioral changes and avoid potentially dangerous situations such as driving.
- Daily physical activity. Aerobic exercise is significant for both staying awake during the day and falling asleep at night. Regular exercise can also help improve sleep quality and improve overall health.
- Refusal of some products. Avoid caffeinated drinks and alcohol as they disrupt your night’s sleep. Sugar and carbohydrates cause a dramatic decrease in hypocretin in the brain after a few hours, so most people feel sleepy, and patients with narcolepsy may experience increased daytime symptoms, including cataplexy.
- Nutrient-rich diet. Certain nutrients, such as magnesium and B vitamins, can help control the symptoms of narcolepsy. A diet that is low in carbohydrates and rich in nutrients will optimize your body’s performance throughout the day.
In addition to getting normal sleep, patients are encouraged to seek psychological help to cope with the difficulties that come with coping with the disease.