Parkinson’s disease is the most common neurological disease after Alzheimer’s Disease, leading to cell degeneration (cell death) in the brain and loss of neurons that produce a molecule called dopamine in the brain. Dopamine-secreting cells are located in the substantia nigra region of the brain stem and are in close association with another region in the brain called the basal ganglia that regulates motor movement. When the cells in the substantia nigra die, the stimulant effect of the basal ganglia in the cerebral cortex decreases as the basal ganglia does not receive sufficient dopaminergic signal, and thus complaints such as slowing of movements, tremors and loss of balance occur.
Parkinson’s disease occurs especially in advanced ages, and onset before the age of 50 is very rare. It is observed approximately twice as frequently in men as in women, and its incidence is 1% in people over the age of 60. Its incidence is approximately 300 per 100,000 people, and it is thought that the number of Parkinson’s patients will increase in the coming years, as the number of people aging gradually increases in our society.
It is known that there is a genetic predisposition to Parkinson’s disease. It is seen more frequently in people with certain genetic mutations (LRRK2, α-synuclein, parkin genes), which have been revealed in recent years, compared to people who do not have these mutations. Family history is more prominent, especially in people who have Parkinson’s disease at a young age. Patients with essential tremor are 4 times more likely to develop Parkinson’s disease in advanced ages. In some studies, it has been shown that the risk of developing Parkinson’s disease increases in people who are exposed to certain drugs used in well water use, rural life and agriculture.
Symptoms of Parkinson’s disease; Chills at rest (tremor), slowing of movements (bradykinesia), stiffness in the muscles that make passive joint movements difficult (rigidity), deterioration of standing balance (postural instability), some other symptoms may occur before the motor symptoms of Parkinson’s disease appear, and these include pain, odor sleep disorder, REM sleep behavior disorder (it is a sleep disorder that occurs with some movements such as hitting, which may cause vivid dreams at night and harm those around them), and autonomic system (bladder-intestinal, blood pressure changes) disorders. When the typical signs of Parkinson’s disease begin to appear, not shaking the arms normally at both sides while walking, tremors in the hands and legs or in the chin during rest, mask facial symptom with loss of facial expressions, progressively smaller and difficult to read writing, decrease in the number of blinks, forward-leaning and walking slowly, walking with small steps, slowing of movement and speaking speed, swallowing disorders, constipation, sexual dysfunctions, depression, psychosis, daytime sleepiness, and impulse control disorder can also be observed together.
Medication is the first line in the treatment of Parkinson’s disease and its basis is the replacement of decreased dopamine. If dopamine is taken orally, it is not possible to cross the blood-brain barrier and reach the brain, so a molecule called L-Dopa is used, which enables dopamine to be synthesized in the body. In Parkinson’s disease, molecules that have dopamine-like effects by binding to dopamine receptors (dopamine agonists) are also used. In addition, anticholinergics, which have a greater effect on tremor, and a drug called amantadine, which has a greater effect on involuntary movements, are also used in the treatment. Treatment in Parkinson’s disease is individual, not disease-specific, and is tailored to the type and severity of the patient’s symptoms. Let’s not forget that the drugs are only symptom-relief drugs and do not change the natural course of the disease, which worsens over the years. However, in recent studies, evidence has been found that rasagiline, one of the MAO-B inhibitors, changes the course of the disease. In addition to oral dopamine agonists, drugs that are injected under the skin with the help of a small pump used especially in patients with motor freezing problems have also been produced.
The target in the surgery of Parkinson’s disease is to decrease the activity in the subthalamic nucleus, globus pallidus and thalamus where increased activity is observed in the disease. Two methods can be used for this purpose; In one, these areas are burned, in the other, an electrode is inserted into this area and its activity is reduced with the help of a battery. Surgery is not the first treatment option in Parkinson’s disease, nor is it the last treatment option. A bedridden Parkinson’s patient cannot benefit from surgical treatment. Surgical treatment should be considered especially in patients who respond well to drug treatment but cannot receive effective treatment due to side effects or fluctuations of drugs, are younger than 70 years old, have a definite diagnosis of Parkinson’s disease, can be followed well after surgery, and do not have serious psychiatric disease or dementia. Surgery can provide a half reduction in Parkinsonism findings in appropriately selected patients.
