Parkinson's disease

Last updated date: 28-Oct-2023

Originally Written in English

Parkinson’s disease

Parkinson's disease is a neurological condition that leads to the loss of motor control. This ailment typically commences gradually and advances progressively. Individuals with Parkinson's disease may experience trembling, muscle stiffness, and difficulties with walking and maintaining balance and coordination.

As the condition advances, individuals may also encounter challenges with speaking, sleeping, cognitive functions, behavioral changes, and various other symptoms.

Though there is no known cure for Parkinson's disease, there are medications available to alleviate the associated symptoms. In some instances, medical professionals or neurologists might recommend surgical interventions to manage symptoms by regulating specific areas of the brain.

 

Recognizing Signs and Symptoms of Parkinson's Disease

Symptoms of Parkinson's disease tend to manifest gradually. They often start with minor tremors in one hand and a sensation of bodily rigidity. As time goes on, additional symptoms become apparent, and some individuals may even develop cognitive impairments.

Here are some early indicators of Parkinson's disease:

  1. Altered motor function, including tremors.
  2. Challenges in maintaining balance and coordination, leading to potential accidents or falls.
  3. Reduced sense of smell due to nerve-related changes affecting facial muscles.
  4. Changes in walking pattern, such as a slight forward lean or shuffling.
  5. Voice tremors or a softer tone.
  6. Handwriting that becomes smaller and more cramped.
  7. Sleep disturbances attributed to restless legs and other underlying factors.

Movement-related symptoms may initially affect one side of the body and gradually progress to the other side. Furthermore, individuals with Parkinson's disease may experience additional common symptoms, including:

  1. Mood changes, such as depression.
  2. Difficulties with chewing and swallowing.
  3. Constipation.
  4. Fatigue.
  5. Skin issues.
  6. Over time, the development of dementia, hallucinations, and delusions may also occur.

 

Causes and Risk Factors of Parkinson's Disease

Causes of Parkinson’s disease

Parkinson's disease is primarily a neurological disorder that arises from abnormalities within the brain. While the precise underlying cause remains uncertain, researchers have identified certain contributing factors:

  1. Decreased Dopamine Levels:

    • Parkinson's disease is closely associated with reduced dopamine levels, a neurotransmitter essential for regulating motion and coordination.
    • This decline in dopamine production results from the loss of dopamine-producing brain cells.
    • Decreased dopamine levels can impede an individual's ability to control their movements, and as dopamine levels diminish, symptoms become more pronounced.

  2. Reduced Norepinephrine Levels:

    • Damage to nerve terminals responsible for producing norepinephrine, a neurotransmitter involved in blood flow and essential bodily functions, may also play a role in Parkinson's disease.
    • Low norepinephrine levels in Parkinson's disease can contribute to both motor and nonmotor symptoms, including tremors, depression, anxiety, and stiffness.

  3. Lewy Bodies:

    • In the brains of Parkinson's disease patients, the presence of clumps of alpha-synuclein protein, known as Lewy bodies, is observed.
    • Accumulation of Lewy bodies can lead to the death of nerve cells, resulting in disturbances in movement, behavior, cognition, and mood.
    • This accumulation may even lead to the development of dementia.

It's important to note that while Lewy body dementia shares similar symptoms with Parkinson's disease, they are distinct conditions. However, some individuals may experience both disorders simultaneously due to the symptom overlap.

  1. Genetic Factors:
    • While specific gene mutations have been linked to Parkinson's disease, it is not typically considered a hereditary condition.
    • Genetic factors are implicated in only around 10% of cases, primarily among those with early-onset forms of the disease.

 

Exploring Parkinson's Disease Risk Factors

Several environmental factors are associated with an elevated risk of developing Parkinson's disease, including:

  1. Prior Traumatic Brain Injury:

    • Head injuries, especially those sustained in contact sports, can increase the likelihood of developing Parkinson's disease.

  2. Exposure to Toxins:

    • Contact with toxins such as pesticides, metals, solvents, and environmental pollutants has been linked to an increased risk of the condition.

  3. Gender Disparity:

    • Men are approximately 1.5 times more likely to develop Parkinson's disease compared to women.

  4. Age:

    • Parkinson's disease typically emerges between the ages of 50 and 60, with only about 4% of cases appearing before the age of 40.

  5. Family History:

    • Individuals with close relatives who have experienced Parkinson's disease have a heightened risk of developing the condition.

 

Diagnosis of Parkinson's Disease

Diagnosing Parkinson's disease can be challenging, as early symptoms may resemble those of other conditions, and there are no specific blood or lab tests available for detection.

To arrive at a Parkinson's disease diagnosis, a healthcare provider will begin by gathering your general medical history and inquiring about any family history of neurological disorders. They will also assess your current symptoms, medications you are taking, and potential exposure to toxins.

Clinical examinations will involve observing your gait, posture, coordination, and assessing the presence of tremors or muscle stiffness. In certain cases, computerized tomography (CT) or magnetic resonance imaging (MRI) scans may be employed to rule out other conditions that manifest similar symptoms.

 

Treatment for Parkinson's Disease

While there is no known cure for Parkinson's disease, several treatment options aim to alleviate the associated symptoms. Physical exercise has shown to significantly reduce these symptoms.

Additional therapies, such as physical therapy, occupational therapy, and speech-language therapy, can aid in addressing issues related to mobility, balance, feeding and swallowing difficulties, and communication. In some cases, surgical interventions may be considered as an alternative.

Medications for Parkinson's Disease

Various medications can be prescribed to manage Parkinson's disease symptoms, including:

  1. Levodopa:
    • Levodopa is the most commonly used medication for treating Parkinson's disease.
    • It helps restore dopamine levels, improving symptoms in approximately 75% of cases.
    • Typically, levodopa is administered in combination with carbidopa, which slows down the breakdown of levodopa, enhancing its availability at the blood-brain barrier.
  2. Anticholinergics:
    • Anticholinergics work by inhibiting the parasympathetic nervous system, reducing muscle stiffness.
    • Medications like benztropine (Cogentin) and trihexyphenidyl are effective in managing Parkinson's disease.
  3. Dopamine Agonists:
    • Dopamine agonists mimic the effects of dopamine in the brain and are used when levodopa is less effective.
    • Drugs such as bromocriptine, ropinirole, and pramipexole fall into this category.
  4. Amantadine (Symmetrel):
    • Amantadine is often used in conjunction with carbidopa-levodopa.
    • It acts as a glutamate blocker and provides temporary relief from levodopa-induced dyskinesia (involuntary movements).
  5. COMT Inhibitors:
    • Catechol O-methyltransferase (COMT) inhibitors, like entacapone (Comtan) and tolcapone (Tasmar), extend the effects of levodopa.
    • Tolcapone, though, carries a risk of liver damage and is reserved for cases unresponsive to other treatments, while entacapone does not pose a liver risk.
    • Stalevo medication combines entacapone with carbidopa-levodopa in a single pill.
  6. MAO B Inhibitors:
    • Drugs such as selegiline (Zelapar), safinamide (Xadago), and rasagiline (Azilect) are examples of MAO B inhibitors.
    • They block the enzyme monoamine oxidase B (MAO B) in the brain, preventing dopamine breakdown.
    • Selegiline, when taken with levodopa, helps prolong the effectiveness of the drug.

 

Surgical Interventions for Parkinson's Disease

Deep brain stimulation

For individuals who do not respond to medications, therapies, or lifestyle adjustments, surgical procedures may be considered. Neurologists may recommend the following surgical treatments for Parkinson's disease:

  1. Deep Brain Stimulation (DBS):

    • DBS involves implanting electrodes in the brain to deliver electrical impulses. These impulses disrupt or modify abnormal brain activity responsible for Parkinson's disease symptoms.
    • DBS is particularly effective in addressing significant motor symptoms, such as bradykinesia (slowness of movement), tremors, and rigidity.
    • It should be noted that DBS does not improve non-motor symptoms like hallucinations, memory issues, or depression.
    • Patients considered for DBS typically have failed to achieve symptom control through medication and meet stringent criteria.

  2. Pallidotomy:

    • Pallidotomy is a surgical procedure that involves the targeted destruction of a small brain area called the globus pallidus, which regulates movement.
    • This procedure is recommended to alleviate symptoms like involuntary movements (dyskinesias), tremors, and muscle rigidity.

  3. Thalamotomy:

    • Thalamotomy is the surgical destruction of a small portion of the thalamus and may benefit a select group of individuals with severe arm or hand tremors.

 

Complications Associated with Parkinson's Disease

Parkinson's disease often co-occurs with other conditions that are potentially treatable, including:

  1. Cognitive Impairments:

    • Problems with thinking and memory can be associated with Parkinson's disease.

  2. Emotional Disturbances:

    • Patients may experience depression and emotional fluctuations as part of their condition.

  3. Swallowing Difficulties:

    • Issues related to swallowing can arise in some cases.

  4. Sleep Disturbances:

    • Sleep problems or sleep disorders are common among individuals with Parkinson's disease.

  5. Feeding and Chewing Difficulties:

    • Difficulty with feeding and chewing can be a challenge for some individuals.

  6. Gastrointestinal Issues:

    • Constipation is a frequent problem, often linked to the slower digestive system in Parkinson's disease.

  7. Urinary Problems:

    • Bladder issues, including difficulty urinating and urinary incontinence, may be experienced.

 

Conclusion 

Parkinson's disease is a chronic neurological condition that leads to a range of physical and cognitive abnormalities. While the precise causes of the disease remain unclear, there are strong associations with factors such as previous traumatic brain injury and toxic exposure.

While there is no known cure for Parkinson's disease, medications can help most patients maintain a reasonable quality of life. In certain cases, surgical procedures may offer relief from symptoms. It's essential for individuals with Parkinson's disease to work closely with their healthcare providers to explore the most suitable treatment options and symptom management strategies.