Essential tremor: what it is, symptoms and treatment

Essential tremor is a disease of the nervous system with hereditary predisposition. Characterized by the trembling of hands, tongue, chin, head, voice, rarely - other parts of the body. Can be combined with other symptoms of nervous system damage. It often manifests itself after 30-40 years. In itself, this disease does not pose an immediate danger, but it can significantly hamper social and professional activities. The main drugs for treatment are β-adrenoblockers and anticonvulsants, with ineffectiveness of medicamental influence, surgical treatment is possible. Let's find out in more detail what kind of disease it is, what are its main symptoms and how it is treated.

Essential tremor has many synonyms: Minor's disease, family tremor, hereditary idiopathic trembling, benign, congenital tremor. These terms mean the same disease. It was first described in 1887. The frequency of occurrence of an essential tremor is, %. It affects men and women with equal frequency. The older a person becomes, the higher the risk of an essential tremor. Thus, in middle-aged people, the prevalence of pathology is approximately 300-415 per 100 000 population, and after 65 years - 616 per 100 000 population.

Causes

Disease is the result of genetic disorders. To date, it has been found that with the essential tremor of mutation, the 2nd or 3rd chromosomes are exposed. It is believed that the disease is transmitted by an autosomal dominant type. This means that the genetic mutation is not associated with the sex chromosome, but with the usual - autosomal, and therefore manifests itself in both men and women. Dominance means the ability of a gene to always manifest, even if the second analogous gene is normal (all human genes are paired). That is, if the pathological gene originated in the family, then it will find itself a disease in all generations. But for an essential tremor, a different degree of manifestation of the manifestation of a mutation is characteristic: someone the tremor will be insignificant, only the brushes will be captured, while the other will be common, in different parts of the body.

In some patients, the genetic defect can not be identified, which indicates the polygenic coding of this disease.

A characteristic feature of essential tremor is this phenomenon: in subsequent generations, the disease begins at an earlier age and is more severe than in the previous ones.

There are two forms of the disease:

• family: signs of the disease are traced in previous generations;
• sporadic: the symptoms occur for the first time in one of the family members (when a new sudden mutation of the gene occurs).

Symptoms

At the onset of the disease, tremor occurs when performing any purposeful movements, at later stages it does not go away and at rest.

The main clinical manifestation of essential tremor is a trembling in the hands that occurs:

• when giving the hands a certain posture (for example, pulling out straight arms forward and holding in this position): postural tremor;
• when performing any purposeful movement (for example, touching the tip of the nose with your finger): intentional tremor;
• at rest: a tremor of rest.

The most characteristic for this disease is postural and intentional tremor. Usually, the changes that have arisen are symmetrical, although the onset of the disease with unilateral localization is possible. In the beginning, the tremor appears only with tension, prolonged performance of any work by hands, but gradually it begins to disturb the patient and with minor movements and even at rest.

Trembling occurs due to the alternation of contraction of flexor muscles and extensor muscles of the fingers and hands. The tremor frequency is from 4 to 12 Hz, the amplitude of jitter is small. With age, the tremor frequency may decrease somewhat, and the amplitude increase.

Emotional tension, fatigue, lack of sleep, attempts by strong-willed effort to suppress shaking, drinking coffee, strong tea and energy drinks, staying in the cold only intensify the symptoms. A characteristic feature is the appearance of a tremor only in wakefulness, in the period of sleep the tremor disappears.

Alcohol has a special effect on the symptoms of essential tremor. After intake for several hours, there is a decrease and even disappearance of the symptoms, but the next day they come back and sometimes even have a greater degree of severity than before they are consumed alcohol. This feature can lead to an addiction to alcohol and the development of alcoholism in patients with an essential tremor.

In addition to the hands, as the disease develops, other parts of the body are involved in the pathological process:

• language: the trembling of the tongue leads to inarticulate speech (dysarthria);
• lips, cheeks, forehead, whiskey, eyelids (occurs in 60% of patients): it looks like mimic twitchings;
• head (happens in 50% of patients): nodding, rocking movements like "yes-yes "no-no
• larynx with vocal cords (with a disease experience of more than 10 years): manifested by voice trembling, change in timbre, also leads to blurred speech;
• diaphragm: the main respiratory muscle. Involving it in the process can be accompanied by a violation of the rhythm of breathing and also leads to peculiar changes in speech (it becomes jerky and incomprehensible);
• legs: the trembling of the lower extremities occurs only in 20% of patients with significant experience of the disease. Usually not sharply expressed, at least, does not hamper movement.

Since the onset of tremors in the hands before the involvement of other parts of the body, years usually pass.

Essential tremor can be combined with other extrapyramidal disorders: parkinsonism, involuntary movements, violation of muscle tone. The tone rises slightly, never reaches the same degree as in Parkinson's disease. Of involuntary movements, the most common are:

• "Writing spasm the inability to use the pen due to the pronounced muscle tension that occurs when the patient takes a pen or pencil in his hands;
• Blepharospasm: involuntary muscle contractions of the eyelids;
• spastic torticollis: forced position of the head in the form of a small turn and tilt of the head;
• oromandibular dystonia: a violation of the tone of the chewing muscles with simultaneous grimacing, opening the mouth, jaw movements to the sides.

With regard to the age of the onset of the disease, several forms are distinguished:

• children's;
• youthful;
• a form of mature age;
• presenilnaya;
• senile.

Diagnostics

To exclude other causes of tremors, an additional examination is performed.

For the diagnosis, the type and localization of tremor, the slow progression of the disease and its good quality, because tremor does not carry a threat to life, does not reduce life expectancy, but only deteriorates its quality.

In addition to the data of the anamnesis (including the presence of similar symptoms in relatives) and objective neurological examination, a major role in diagnosis is played by computed tomography (CT) or magnetic resonance imaging tomography (MRI). These studies are conducted for the purpose of differential diagnosis in order to distinguish between essential tremor from other diseases of the nervous system (Parkinson's disease, torsion dystonia, multiple sclerosis and etc.). A feature of essential tremor is the absence of pathological changes in CT or MRI. And other diseases will have signs on CT or MRI.

Treatment

For the treatment of essential tremor, several groups of drugs are used:

• β-adrenoblockers (Anaprilin, Propranolol, Obsidan, Metoprolol): The most effective is Propranolol. He is prescribed in a dose of 60 to 320 mg / day in 3 divided doses under the control of blood pressure and pulse. There are prolonged forms that allow taking the drug once a day. Propranolol is contraindicated in bronchial asthma, bradycardia, hypotension, Raynaud's disease, severe heart failure;
• anticonvulsants (Primidone = Hexamidine 50-250 mg / day, Clonazepam-2 mg / day, Gabapentin);
• tranquilizers (lorazepam, diazepam, oxazepam);
• intramuscular injection of large doses of vitamin B6 (200-400 mg / day) for a month, the courses are conducted 2 times a year;
• intramuscular injections of botox (the nerve endings in the muscle are blocked and it does not contract). On average, the effect persists for about 10 weeks after administration.

Of all these drugs, preference is given to β-blockers, they are considered to be the most effective. Otherwise, the selection of the drug is a trial run from the remaining groups.

In some cases, acupuncture and relaxing massage are effective.

When all types of conservative treatment are unsuccessful, resort to surgical methods of correction. Operational interventions are of two types:

• Destroying (destruction of ventrolateral nuclei of the thalamus and subthalamic nucleus);
• stimulation (deep stimulation of the brain): implantation in the brain of electrodes, which generate electrical impulses, suppressing tremor.

Forecast

Essential tremor is absolutely not a dangerous disease. Its progression does not pose a threat to the patient, does not affect the life expectancy, does not reduce the intellect. However, symptoms can significantly impair professional skills and interfere with self-service (pronounced tremor makes it impossible even to eat, to dress independently).

Completely get rid of the disease is impossible, but systematic treatment allows you to reduce symptoms to a minimum, practically not complicating the life of the patient.

Thus, essential tremor is a disease with which one can learn to live fully. Has a hereditary predisposition. The main symptom is jitter, which depends on many factors. Medication or surgical treatment can reduce all manifestations of the disease to naught. Therefore, if a tremor occurs, consult a doctor as soon as possible.

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