Narcolepsy
Narcolepsy is a disease of the nervous system, which is manifested by attacks of irresistible drowsiness and sudden falling asleep. Sometimes patients have short-term paralysis of the whole body after waking up. Narcolepsy is most often diagnosed in young people, mainly in men. The prevalence ranges from 20-40 cases per one hundred thousand people.
The content of the article:
Etiology and pathogenesis of narcolepsy
Symptoms of narcolepsy
Diagnosis of narcolepsy
Treatment of narcolepsy
Prognosis and prevention of narcolepsy
Narcolepsy
The methods of therapy of narcolepsy used today are aimed only at its correction, and not at its complete elimination. To eliminate the symptoms of the disease, doctors prescribe normalization of sleep and wakefulness, as well as drug therapy. With proper and timely treatment, it is possible to improve the quality of life of the patient and minimize the number of daytime sleepiness attacks.
Etiology and pathogenesis of narcolepsy
The exact causes of narcolepsy have not yet been established by scientists. For a long time it was believed that the etiology of the disease is closely related to mental disorders. However, this theory has not been confirmed. Nowadays, a theory is being actively investigated that proves that the disease occurs due to a lack of a neurotransmitter that is responsible for maintaining wakefulness. Namely, the biologically active substance, the deficiency of which leads to narcolepsy, may be hypocretin. This deficiency can be genetically determined or occur in the case of severe fatigue, severe infection, pregnancy, traumatic brain injury.
Another theory proves the autoimmune mechanism of the pathology. The proof of this theory is that abnormal T-lymphocytes are found in patients with narcolepsy. In addition, the autoimmune origin of the pathology is indicated by the beginning of its development after vaccination or the detection of infectious diseases (measles, influenza). No more is known about the pathogenesis of pathology than about its origin. Scientists suggest that the main problem of the disease lies in the untimely phase of rem sleep — it is introduced both during wakefulness and the phase of slow sleep.
Symptoms of narcolepsy
The clinical picture of the disease includes four main symptoms: daytime drowsiness, cataplexy, hypnagogic hallucinations and insomnia. Usually, patients have several of these symptoms at the same time, all four symptoms are diagnosed at once in 10% of cases.
Daytime sleepiness
A patient with narcolepsy has several attacks of irresistible drowsiness during the day. Such attacks can be both single and numerous. The duration of seizures ranges from a few minutes to a couple of hours. The patient is practically unable to resist sudden falling asleep, but it is possible to wake him up in the same way as with normal sleep. In most cases, seizures occur in a monotonous environment, which can cause drowsiness in a healthy person (reading, watching TV).
The patient can also fall asleep in critical situations that require increased attention (while eating, talking, driving a car). After waking up, the patient often feels rested and cheerful, but after a couple of minutes he can fall asleep again. Night sleep in patients with narcolepsy is often fragmented and accompanied by nightmares, resulting in low productivity and efficiency during the day. Patients have a decrease in motivation, poor concentration of attention, they may experience depression. Patients with narcolepsy are prone to increased traumatism.
Cataplexy
This condition is characterized by sudden weakness in the muscles and paralysis caused by emotional reactions such as joy, fear, anger, surprise. Weakness can manifest itself both in one limb and be generalized. In the latter case, after the emotional impact, the patient suddenly falls like a mowed-down. Cataplexy is observed in a third of all patients with narcolepsy.
Hypnagogic hallucinations
Patients with narcolepsy may experience unusual visual and auditory hallucinations while falling asleep. They resemble excessively vivid dreams that occur during the rem sleep phase. Most often, such illusions bother children. Hallucinations are rarely diagnosed in adult patients.
Sleep paralysis
A quarter of all narcolepsy patients suffer from sleep paralysis. This is a transient weakness in the muscles that occurs when falling asleep or waking up. It does not allow the patient to make arbitrary movements. Patients usually feel a strong fear due to the inability to move.
Diagnosis of narcolepsy
It is not possible to diagnose narcolepsy in a patient right away — on average, the diagnosis is made 10 years after the onset of the disease. Examination of patients who complain of symptoms characteristic of narcolepsy is carried out by a neurologist. It should be borne in mind that the disease is similar in its clinical manifestations to many other neurological pathologies. That is why, for the most accurate diagnosis, consultations of specialists such as a psychiatrist, an endocrinologist, an epileptologist, an infectious disease specialist, a gastroenterologist may be required.
Differential diagnosis
It is necessary to differentiate narcolepsy primarily from epilepsy. The symptoms of pathology are also similar to the clinic of other types of hypersomnia: psychophysiological, post-traumatic (provoked by a traumatic brain injury, the presence of intracerebral hematoma), psychopathic (occurs against the background of mental disorders like schizophrenia or hysteria), associated with inflammatory, tumor or vascular, cerebral diseases caused by somatic pathologies (diabetes mellitus, pernicious anemia, hypothyroidism, liver failure).
Polysomnography
It is possible to diagnose the disease with the help of polysomnography, which is accompanied by EEG registration and an MSLT test. A deep and maximally accurate study of pathology is carried out by a somnologist in the laboratory. The technique of polysomnography provides for a thorough study of the patient’s night sleep. To do this, you need to spend the whole night in a specially designed office under the supervision of a doctor. With the help of this technique, it is possible to detect a violation of the alternation of sleep phases: an increase in the duration and frequency of the fast sleep phase. Also, the technique allows you to exclude similar sleep disorders.
MSLT test
The next day after the polysomnography, the doctor may prescribe an MSLT test to the patient. Namely, the patient will need to try to fall asleep five times during the day. The interval between periods of short-term sleep should be about 2-3 hours. After the MSLT test, the doctor can make a diagnosis if at least two episodes of sleep are confirmed. For a more accurate study of the disease, the doctor may prescribe the definition of periods of latent drowsiness. Differential diagnosis of narcolepsy provides the following diagnostic measures: ophthalmoscopy, duplex scanning, MRI of the brain, cerebral vascular ultrasound.
Treatment of narcolepsy
There is no effective method of treating the disease today. However, a properly selected scheme, taking into account the individual characteristics of the patient, makes it possible to facilitate his well-being and eliminate the most pronounced manifestations of pathology. In order to normalize the patient’s condition and improve the quality of life, long-term treatment will be required. At the same time, it will still not be possible to completely remove all the symptoms of narcolepsy.
Sleep mode
Treatment of patients with narcolepsy should begin with the normalization of their sleep and wakefulness. It is strongly recommended to go to bed and wake up at the same time. Almost all patients are shown the following sleep mode: 7-8 hours of night sleep and two periods of daytime sleep from 15 minutes to half an hour. It is also important to take care of the quality of sleep. To do this, in the evening it is necessary to avoid overeating, eating heavy food, drinking alcohol.
In addition, patients should change their lifestyle: reduce the impact of stressful situations, significantly reduce the use of stimulants (coffee or nicotine), and start actively exercising. Often, people suffering from narcolepsy have a malfunction of the biological clock, so they are active at night, and feel sleepy during the day. For them, it would be ideal to choose a job that coincides with the natural sleep cycle. Such a regime will allow you to get rid of the need to force your body to adhere to the standard operating mode and take stimulant medications to eliminate drowsiness.
Patients with narcolepsy are shown a short daytime nap. It is very important to plan your day so that at least twice you can take a nap for 10-15 minutes. Such a dream is not able to fully replace the night, but it will allow you to overcome daytime drowsiness.
Medical treatment
Drug treatment of patients with mild or moderate drowsiness begins with the appointment of modafinil, which stimulates wakefulness. At the same time, the drug does not cause feelings of euphoria and addiction syndrome. It is recommended to take it in the morning in an amount of 100-200 mg orally. If this amount of the drug is not enough to relieve the symptoms of the disease, in this case, the doctor additionally prescribes another 100 mg. In the most difficult situations, according to indications, you can increase the daily dose to 400 mg.
If narcolepsy cannot be treated with modafinil, in this case, the patient is prescribed amphetamine derivatives: methylphenidate or dextroamphetamine. However, it must be remembered that these medications have serious side effects: addiction with a high risk of addiction, tachycardia, arterial hypertension. To reduce the frequency of cataplexy, patients with narcolepsy are prescribed the following drugs: serotonin reuptake inhibitors (prozac), tricyclic antidepressants (anafranil and tofranil)
