Parkinson’s disease: causes, symptoms, treatment and prevention.

One of the most common neurodegenerative diseases; it especially affects motor skills.

Parkinson's is the most common neurodegenerative disease after Alzheimer's disease. It is estimated that approximately 1% of people over the age of 60 suffer from this disorder.

Although Parkinson's disease is thought to have genetic causes and therefore can hardly be prevented or cured, there are treatments capable of alleviating its symptoms and delaying the physical and cognitive deterioration it entails, especially drugs such as levodopa.

What is Parkinson's disease?

Parkinson's disease affects the regions of the brain that produce dopamine, a neurotransmitter that enables precise, voluntary movements. that allows for voluntary and precise (fine) movements as well as other non-motor functions.

The main symptoms of this disease, described by James Parkinson in 1817, include resting tremors, muscular rigidity, and tremors at rest, muscle rigidity, and speech and gait impairment. and impairment of speech and gait.

Parkinson's disease usually begins between the ages of 50 and 60 years, although it is not uncommonThe course of the disease is chronic and usually causes severe disability in the sufferer after about 10 years.

Although some treatments can alleviate the symptoms, once Parkinson's disease has developed there is no cure.

Causes of Parkinson's disease

The symptoms of Parkinson's disease are a consequence of the degeneration of subcortical brain structures.. The destruction of dopaminergic neurons in the basal ganglia, especially in the region known as "substantia nigra", hinders multiple cognitive and motor functions.

The causes of Parkinson's disease are unknown. It is known that there is a genetic component, since 15% of diagnosed persons have close relatives who also suffer or have suffered from this disorder.

The development of Parkinson's is probably due to a combination of mutations in several genes. combination of mutations in several genes. Exposure to some toxins, such as those present in pesticides, herbicides and heavy metals, is also considered a risk factor, although the importance of these environmental factors seems to be less than that of genetic factors.

Symptoms

Early symptoms of Parkinson's disease usually include mild tremors that progressively intensify. The same is true for the rest of the symptoms, which are also related to movement.

Other early signs are stiffness of the arms when walking, difficulties in articulating sounds and lack of facial expressiveness (the "mask face" characteristic of this disease).

Subsequently all these symptoms will worsen as the degree of brain involvement increases, evolving in many cases to the diagnosis of dementia caused by Parkinson's disease.

Resting tremors

Resting tremors are slow and widespread and occur in a part of the body that is not making any movement.. They are very characteristic of Parkinson's disease, to the point that in many cases they are called "Parkinsonian tremors".

They usually begin in one of the hands, but as the disease progresses they generalize to both arms and may also affect the legs and head.

Resting tremors generally occur together with muscle stiffness and motor slowness, and occur to a lesser extent during voluntary movements.

Muscle rigidity

The increased muscle tone that occurs as a result of Parkinson's disease in turn leads to stiffness in the muscles, which limits movement and causes pain during voluntary movements. limits movement and causes pain.

Characteristic of Parkinson's disease is what is known as "cogwheel stiffness", which means that when another person moves the patient's affected limbs, they stop, showing excessive resistance, as if there were something blocking the joints. However, the problem is not in the joints, but in the muscle activation patterns that the nervous system orders in real time.

3. Bradykinesia (motor slowness)

Parkinson's disease progressively hinders movements, especially those of the limbs. This decreases the ability to perform simple manual tasks, which are becoming slower and slower.which are increasingly slower to perform. It also makes it more difficult to sit up and walk.

On the other hand, the difficulties caused by these motor difficulties also lead to a low willingness to move, so that a psychological effect is added to the motor symptoms, which overlaps with the above.

4. Loss of automatic movements

The involvement of the basal ganglia causes a progressive loss of automatic movements in people with Parkinson's disease. This is manifested in the absence of blinking, smiling and arm swinging when walking..

5. Posture and balance problems

In Parkinson's disease, postural reflexes are affected, resulting in a stooped and flexed posture. stooped and flexed posture which in turn causes lack of balance or postural instability, facilitating falls and making it more difficult to move. In addition, in the case of falls, avoiding falling to the ground with full weight and then getting up also costs more.

6. Gait impairment

One of the most visible consequences of the motor problems mentioned above are changes in gait. People with Parkinson's disease usually take shorter steps, shuffle their feet and move their arms less when walking. and move their arms less when walking.

Difficulties occur in all phases of gait, so that not only walking becomes more difficult, but also the ability to initiate walking, to turn and to stand is diminished.

7. Speech difficulties

Some of the most common speech problems in Parkinson's cases include decreased loudness and slurred speech difficultiesThe articulatory organs are affected by motor impairment of the articulatory organs.

Likewise, prosody is altered, speech may be accelerated (tachyphemia) and some words and phrases may be compulsively repeated (palilalia). These symptoms seem to be more frequent in cases where Parkinson's disease occurs with dementia.

As a consequence, the person's social life is impaired, and sometimes predisposes him/her to seek isolation.

8. Dementia

The alterations caused by Parkinson's disease in the brain can lead to the development of a form of dementia specific to this disease. a form of dementia specific to this disease.

Dementia is diagnosed in 20-60% of Parkinson's cases, although a lesser degree of cognitive impairment may also occur in the remainder. Dementia caused by Parkinson's disease is especially likely if the patient is male, is older, has a late onset or does not respond well to medication.

Compared to Alzheimer's disease, the most common cause of severe cognitive impairment, in Parkinson's dementia motor impairment is more prominent at the onset. This is due to the dopamine deficit deficit inherent to Parkinson's disease. In contrast, cognitive symptoms are more intense in the early stages of Alzheimer's disease.

However, as Parkinsonian deterioration progresses, cognitive symptoms such as memory loss and delusions increase. The different types of dementia differ less from each other when they are in the advanced stage.

Prevention and treatment

It is not clear whether the onset of this disease can be prevented. Some studies suggest that the consumption of caffeine and green tea reduces the risk of Parkinson's disease.

In addition, it has been linked to the practice of moderate-intensity aerobic exercise in adulthood with a lower probability of developing this disease in old age. However, the preventive efficacy of sport has not yet been confirmed, and the same is true for caffeine and green tea.

Once Parkinson's disease has developed, its symptoms can be alleviated using different types of treatment. The management of this disorder is mainly carried out with medication that increases the levels of dopamine in the body.

Levodopa is the most commonly used drug to treat Parkinson's disease, especially in its early stages.. This compound increases the concentration of dopamine. As the disease progresses, levodopa may become less effective, in which case it is replaced by dopamine agonists such as pramipexole and ropinirole.

Other forms of treatment, such as surgery, are less effective than levodopa and similar drugs. Physical exercise and relaxation techniques also help maintain mobility to a greater extent, slowing the progression of Parkinson's disease.