Parkinsonism is a neurological syndrome characterized by rigidity (a sharp increase in muscle tone), hypokinesia (slowness of movement), and tremors of rest, expressed in the limbs’ tremors. This syndrome is formed as a result of damage to certain structures of the brain and slowly progresses.
The most famous and common form of parkinsonism is Parkinson’s disease. This is the so-called primary parkinsonism associated with the degeneration of neurons in the substantia nigra, which regulates muscle tone and many autonomic processes.
However, this is not the only form of parkinsonism; the syndrome can develop due to atherosclerosis of the cerebral vessels, toxic effects, encephalitis, etc.
According to modern concepts, parkinsonism syndrome can be divided into the following categories:
- Primary (idiopathic) parkinsonism. It includes Parkinson’s disease and a unique genetically determined form of early parkinsonism, the so-called juvenile parkinsonism.
- Secondary parkinsonism. This syndrome develops as one of the clinical manifestations of several independent diseases and lesions of the central nervous system. The most famous variants of secondary parkinsonism are vascular, toxic, post-traumatic, post-infectious.
- Parkinsonism in multisystem neurodegenerative diseases. Among the diseases that naturally manifest themselves as syndromes, this parkinsonism should first of all be called progressive supranuclear palsy, multiple systemic atrophy, dementia with Lewy bodies, and cortico-basal degeneration.
- Parkinsonism in hereditary diseases of the central nervous system. This is a vast group of diseases of various genesis, including hepatolenticular degeneration, neuroferritinopathy, dopa-sensitive dystonia, the rigid form of Huntington’s disease, several forms of lipidosis, mitochondrial encephalopathies, etc.
About 10-15% of all cases of parkinsonism occur in Parkinson’s disease.
Parkinson’s disease is the second most common neurodegenerative disease after Alzheimer’s. It is mainly typical for the elderly, but there is also a juvenile form of parkinsonism, which occurs before 20. The disease affects men more often than women.
The main symptoms of Parkinson’s disease result from the death of large dopamine-producing neurons in the compact substantia nigra of the midbrain. Due to the mechanisms of neuroplasticity, symptoms in people with Parkinson’s appear only in the case of death of more than half of the cells of the substantia nigra, which corresponds to a decrease in the level of dopamine in the striatum by 80-85%. Usually, due to the processes of natural aging of the body, starting from the 5th decade of life, from 4.7 to 6% of the cells of the substantia nigra per decade die, which determines the age-dependent nature of Parkinson’s disease.
The main manifestations of parkinsonism are:
- Tremors in the arms or legs, tremors of the head, lower jaw, etc.
- Inconsistency in the movement of the arms and legs while walking.
- Impaired ability to maintain balance.
- Stiffness of the muscles of the spine, limbs, neck, and slowness of voluntary movements.
- Gait in small, accelerating steps.
- Fixation of the body in the so-called supplicant position (the body is tilted forward, the head is lowered to the chest, arms, and hands in a bent position).
- The poverty of facial expressions, rare blinking.
- Difficulty performing complex manipulations.
Moreover, autonomic disorders are noted (for example, greasy face, increased sweating, salivation) and mental changes (emotional dullness, spontaneity).
As parkinsonism develops, the muscle tone increases so much that the patient loses the ability to do anything on his own; most of the time, he is in the supine or sitting position.
With parkinsonism, changes occur in the brain structures, particularly the degeneration of the cells of the substantia nigra of the brain. This structure is responsible for muscle tone and regulates motor function. With its participation, respiration processes, cardiac activity occurs, and vascular tone is maintained.
Many factors can provoke these changes:
- Infectious diseases.
- Poisoning by various substances, including carbon monoxide, lead, mercury.
The hereditary factor also plays a role, but in this case, parkinsonism begins earlier, including in adolescence.
Although this disease has several characteristic external manifestations, the doctor has comprehensive information about the patient’s condition, laboratory diagnostics, general and clinical blood tests, determination of blood glucose, cholesterol, bilirubin, creatinine, beta-lipoproteins, triglycerides are necessary.
Besides, for examining patients with suspected parkinsonism, instrumental diagnostics, electromyography, and electroencephalography are used, which allows specialists to determine the cause of tremors and exclude muscle diseases, to diagnose disorders of brain activity. In addition, to diagnose parkinsonism, specialists refer patients to MRI of the brain, MRI angiography of intracranial arteries.
The examination is carried out in a complex; therefore, the patient is also referred for consultation to narrow specialists (ophthalmologist, physiotherapist, and others).
Early diagnosis is the key to the success of preventive neuroprotective therapy, methods of which are being intensively developed in leading laboratories around the world.
Treatment of Parkinson’s disease
Currently, parkinsonism refers to diseases that cannot be cured. However, some drugs can slow down the development of pathology, prolonging the period of a full life for people with Parkinson’s.
In the later stages of the disease, symptomatic treatment is carried out, which is designed to reduce parkinsonism manifestations. Patients have been prescribed muscle relaxants, vasodilators, and nootropic drugs. Medicinal electrophoresis and exercise therapy are also recommended.
Currently, there are six main groups of antiparkinsonian drugs:
- Levodopa preparations.
- Dopamine receptor agonists.
- Inhibitors of catechol-ortho-methyltransferase.
- Monoamine oxidase inhibitors B.
- Central anticholinergics.
Significant progress has been made in the development of surgical treatments for Parkinson’s disease. Two currently used neurosurgical approaches relate to methods of functional neurosurgery and are aimed at interrupting pallido-thalamo-cortical neuronal circuits. In many cases, the use of these operations is accompanied by a decrease in the severity of tremors and other motor manifestations of Parkinson’s disease.
Deep electrical stimulation has undoubted advantages over operations. In addition, it is characterized by fewer complications and a more pronounced effect on all the main clinical manifestations of parkinsonism. In the world, the experience of deep electrical brain stimulation in Parkinson’s disease has existed for more than 20 years. It shows the achieved clinical improvement, maintaining a decent quality of life in operated patients.
The whole range of therapeutic measures aims to increase motor activity in people with Parkinson’s, reduce muscle stiffness and hyperkinesis, and clinically stabilize neurological symptoms.
New technologies for the treatment of Parkinson’s disease are evolving thanks to advances in fundamental neuroscience. Thus, experimental technologies of gene and cell therapy using recombinant viral vectors and nanoliposomal delivery systems are gradually being introduced more and more. However, in the presence of a clear symptomatic effect of neurosurgical interventions, the most important and still unresolved problem is assessing the neuroprotective potential of these operations. The most critical breakthrough in recent years has been the intensive study of non-dopamine antiparkinsonian compounds that act on adenosine, serotonin, opiate, cannabinoid receptors, making it possible to achieve better control over the diverse symptoms of Parkinson’s disease, especially in its advanced stages.
If you have symptoms of Parkinson’s disease or problems with blood pressure, then seeing your doctor early can help detect the disease at the beginning stage. The sooner you start treatment, the longer you can live a fulfilling life.