Parkinson's Disease: Symptoms, Causes, and Treatment

What is Parkinson's Disease? Symptoms, Causes, and Treatment

Parkinson's disease is a progressive neurological disorder that affects the central nervous system, restricts movement ability, and negatively impacts quality of life. Also known colloquially as "shaking palsy," this disease manifests with symptoms such as movement disorders, tremor, muscle stiffness, and balance problems. It takes its name from James Parkinson, who introduced the disease to medical literature in 1817.

Parkinson's disease generally occurs in individuals aged 60 and above; while the average age of onset is 60, the disease can emerge between the ages of 40-70 or, depending on genetic factors, at earlier ages or even in people in their twenties. It is estimated that approximately 1% of individuals over 60 have this disease, and the number of patients is expected to increase as the population ages. The disease is more common in men than women; the exact reason for this remains unknown.

How Does Parkinson's Disease Develop?

In the human brain, dopamine, which plays an important role in movement ability, is produced in a brain region called the substantia nigra, which controls movement and coordination. Parkinson's disease develops as a result of damage to certain brain cells in this region and decreased dopamine production. Dopamine deficiency leads to difficulties in controlling movements and other symptoms of the disease.

The disease typically progresses slowly; it first appears with slight symptoms in one hand and, over time, the lack of capability and difficulty in movement control can spread throughout the body. As the disease progresses, the amount of dopamine in the brain decreases further and symptoms intensify.

Causes and Risk Factors of Parkinson's Disease

The exact cause of Parkinson's disease is not yet fully understood. It is believed that a combination of genetic and environmental factors plays a role in the development of the disease. While certain genetic mutations can lead to the disease, particularly in familial Parkinson's cases, genetic factors play a more limited role in most sporadic (non-familial) cases.

Risk factors that may contribute to the development of the disease include:

• Advanced age
• Family history of Parkinson's disease
• Living in rural areas
• Use of well water and water supply contamination
• Exposure to pesticides and toxic chemicals
• Being male
• Traumatic head injuries
• High exposure to iron and manganese
• Heavy consumption of animal fats
• Obesity
• High stress
• Having certain genetic characteristics

Some factors are suggested to have protective effects against the disease; however, it is not recommended to use these factors without medical supervision and they may carry risks. Among these factors are coffee and caffeine consumption, regular physical activity, and the use of certain medications with nonsteroidal anti-inflammatory and antihypertensive properties. Although there are observations about the protective effects of smoking and alcohol on dopamine cells, no health professional recommends the use of these substances for protective purposes.

Early Stage Findings of Parkinson's Disease

Early stage findings of Parkinson's disease are generally mild and vague, which is why the diagnostic process can often be challenging. Initial symptoms include:

• Mild tremor in the hands, feet, or jaw
• Reduced facial expressions ("masked face" appearance)
• Speech changes; a lower and less emotional tone of voice
• Changes in gait; shortened steps and dragging feet
• Muscle stiffness and slowing of movements (bradykinesia)
• Balance problems and tendency to fall
• Reduced arm swinging movements
• Fatigue and loss of energy

Symptoms of Parkinson's Disease

As the disease progresses, symptoms become more varied and severe. General symptoms can be listed as follows:

• Tremor
• Slow movement (bradykinesia)
• Muscle stiffness (rigidity)
• Balance and coordination problems
• Changes in facial expression and speech
• Difficulty swallowing
• Difficulty with fine motor skills such as writing or buttoning buttons
• Pain in the arms and difficulty in movement
• Constipation and urinary problems
• Sleep problems
• Mood changes and depression

One of the most frequently observed symptoms is tremor that appears in one hand or fingers when the person is at rest; the reduction in arm swinging movements that normally occur while walking is also notable.

Stages of the Disease

Parkinson's disease progresses slowly and gradually; different symptoms come to the foreground at each stage:

• Stage 1: Symptoms are on one side and mild in degree. Mild tremors are observed; most changes are noticed by the patient and their relatives.
• Stage 2: Posture and gait are affected significantly, with mild level of disability present. Tremors begin to appear on both sides of the body.
• Stage 3: Balance is disrupted and falls occur; movements slow down noticeably.
• Stage 4: Symptoms intensify, and the patient struggles to maintain daily life independently. Stiffness and slowness in movement and behavior occur.
• Stage 5: The patient becomes dependent on a wheelchair and requires full care.

How Does Parkinson's Disease Affect the Body?

In addition to movement-related symptoms, Parkinson's disease can affect other body functions:

• Sleep: Difficulty falling asleep or maintaining sleep, and waking early in the morning are common.
• Mood: Depression, anxiety, or apathy may occur.
• Cognitive Functions: Decline may be seen in thinking, memory, and decision-making abilities.
• Autonomic Nervous System: Problems may develop in the system that regulates involuntary functions such as heart rate, blood pressure, and digestion; constipation, urinary incontinence, and blood pressure drop when standing (orthostatic hypotension) are some examples.

Possible Complications

As the disease progresses, some additional problems may arise beyond movement-related symptoms:

• Depression and anxiety
• Sleep problems and restless leg syndrome
• Cognitive decline; particularly in advanced stages, gradual decline in thinking, memory, and reasoning
• Muscle stiffness, joint pain, and pain related to nerve damage
• Difficulty urinating, urinary incontinence, and urinary tract infections
• Constipation related to immobility, reduced fluid intake, and medications used
• Falls related to muscle weakness and balance disorders
• Social isolation related to physical symptoms and emotional difficulties of living with a chronic disease

How is Parkinson's Disease Diagnosed?

Parkinson's disease cannot be definitively diagnosed with a blood test or a single imaging method. The diagnostic process is based on the patient's complaints, health history, and detailed clinical/neurological examination. During neurological examination, the patient's movement ability, balance, coordination, and muscle strength are evaluated; family history is also reviewed.

In some cases, the doctor may use imaging methods to support the diagnosis or to distinguish other conditions that may cause similar symptoms:

• DaTscan: A test that uses a radioactive tracer to visualize dopamine-producing cells in the brain; a decrease in these cells may be a sign of the disease.
• SPECT (Single Photon Emission Computed Tomography): Used to visualize blood flow to the brain.
• MRI (Magnetic Resonance Imaging): Creates images of the brain to help distinguish other neurological conditions that may cause similar symptoms.

Especially in the early stages of the disease, the diagnostic process can be challenging. Being prepared for questions about symptoms and medical history when visiting the doctor, having a family member accompany if possible, and obtaining a second opinion when necessary can facilitate the process.

Treatment Methods for Parkinson's Disease

There is no definitive treatment method that completely eliminates Parkinson's disease. The main goal of treatment is to slow the course of the disease, alleviate symptoms, and support the patient's quality of life as much as possible. The treatment plan is determined individually by the doctor based on the patient's age, stage of disease, and general health status.

Medication Therapy

The main drug groups that may be prescribed by a doctor include:

• Levodopa: A precursor of dopamine that is converted to dopamine in the brain.
• Dopamine Agonists: Mimic the effects of dopamine; can be used alone or in combination with levodopa.
• MAO-B Inhibitors: Slow down the breakdown of dopamine, usually applied in combination with levodopa.
• COMT Inhibitors: Slow down the breakdown of levodopa, extending its effect.
• Anticholinergics: Used in controlling tremor and muscle stiffness; side effects such as dry mouth, constipation, and blurred vision may occur.

Some points to consider in medication therapy:

• The names of the drugs used and their method of administration should be known by the patient and their relatives.
• Medications should be taken regularly at the recommended dose and times.
• The patient should be closely monitored by the doctor, and dose and time adjustments should be made when necessary.
• The effects and side effects of medications should be closely monitored, and necessary measures should be taken promptly.

In advanced stages of the disease, oral medications may not show sufficient effect. In this case, alternative administration methods such as continuous drug application through a pump placed under the skin or continuous drug administration through a tube extending into the intestines through a hole made in the abdomen may be considered.

Deep Brain Stimulation (DBS)

Deep brain stimulation is a surgical treatment method that may be considered when medication therapy cannot adequately control symptoms. In this method, electrodes are placed in brain regions that control movement; the electrodes are connected to a device similar to a heart pacemaker placed in the chest area, which transmits electrical stimulation to the brain.

DBS can help alleviate symptoms such as tremor, muscle stiffness, movement slowness, and balance/coordination disorders, as well as reduce pain and fatigue. The procedure is performed under general anesthesia, and electrodes are placed in the brain with the help of a stereotactic frame.

DBS does not eliminate the disease; the patient may continue to use medication after the procedure. Additionally, like other surgical procedures, it carries risks such as infection, bleeding, and damage to brain tissue. Therefore, it is important that the doctor performs a detailed evaluation before the procedure and understands that it may not be applicable to every patient in every stage.

Support Therapies

In addition to medication therapy, different support therapies can be added to the treatment plan to support daily life quality:

• Physical Therapy: Can help improve balance, coordination, and movement ability.
• Speech Therapy: Can help support speech and swallowing functions.
• Occupational Therapy: Can help maintain daily living activities such as dressing and eating.
• Gene Therapy: This method, which involves transferring genes to cells, is a promising field still in early stages of research for Parkinson's disease.

Importance of Exercise

Exercise can positively affect many functions in Parkinson's patients such as walking, balance, flexibility, grasping ability, and posture. It is thought that at least 2.5 hours of regular exercise per week can help slow the course of the disease and support quality of life. In addition to regular exercise, healthy nutrition, adequate sleep, and stress management can also contribute to symptoms progressing more comfortably.

How Can Daily Life of Parkinson's Patients Be Facilitated?

As movements slow down and control becomes difficult with disease progression, it is important to avoid factors that may restrict the patient's speech and movements as much as possible:

• Regular speech practice with the patient
• Preference for tools such as forks and spoons that can be comfortably used with trembling hands and are resistant to breaking
• Removal of rugs, carpets, and mats that can get tangled around the feet and create a fall risk
• Elimination of door thresholds in the home
• Arrangement of comfortable seating areas
• Installation of grab bars in bathrooms and toilets
• Use of straws to comfortably drink beverages
• Participation of the patient and relatives in support groups; can be beneficial in terms of emotional support and practical information sharing

Does Parkinson's Disease Turn Into Alzheimer's Disease?

Parkinson's disease and Alzheimer's disease are the two most common types of neurodegenerative disease groups. Both diseases are characterized by brain function impairment and cell loss that occur with age; however, the brain regions they affect and their symptoms are different. Parkinson's disease is primarily associated with movement disorders and motor symptoms, while Alzheimer's disease is associated with impairment in memory and thinking abilities.

These two diseases may appear connected due to some common pathological features (protein accumulation in the brain, cell death, neuron loss). In people with Parkinson's disease, cognitive decline and memory loss may occur as the disease progresses; this condition is called dementia associated with Parkinson's disease and is a different clinical presentation from Alzheimer's disease.

It is known that people with Parkinson's disease have approximately 4-6 times higher risk of developing dementia compared to the general population. For this reason, it is important for Parkinson's patients to pay special attention to brain health and monitor the course of the disease through regular check-ups. In conclusion, Parkinson's disease cannot be said to directly transform into Alzheimer's disease; however, cognitive decline and dementia risk in advanced stages should not be overlooked.

Conclusion

Parkinson's disease is a chronic neurological disorder that can progress differently from person to person, is progressive, and affects quality of life in various ways. Although there is currently no cure that completely eliminates the disease, it is possible to manage symptoms and support quality of life through methods such as medication therapy, physical therapy, deep brain stimulation, and support therapies. Early diagnosis, regular medical follow-up, and an individualized treatment plan play an important role in maintaining patients' ability to continue their daily lives. It is recommended that people with complaints consult a neurology specialist without delay to ensure the diagnostic and treatment process is managed in the most appropriate manner.