Parkinson’s Disease : A Complete Overview

What is Parkinson’s disease?

Parkinson’s disease can be characterized as a progressive motor system disorder causing uncontrollable trembling in various parts of the body, due to a loss of dopamine producing brain cells, as per the NIH. The tremors can affect any part of the body; however hands, arms, legs, jaw and face are more notably affected. Parkinson’s may also slow movements to a degree where completing everyday tasks may become a hassle.

The early symptoms of PD are subtle and progress over a period of time, nevertheless, some cases might progress much more rapidly than others. The ailment affects individuals past their 60’s much more than young adults. It affects one person in every 500 individuals and may affect men and women alike.

Parkinson’s may present itself with a range of accompanying symptoms such as tremors, bradykinesia or slurred motions, however, these symptoms can be treated by a physician, which greatly mends the quality of life for majority of patients. There still seems to be no cure for Parkinson’s but the latest research shows major advancements into various therapies and treatments that provide some relief for the future. Proper diagnosis of the condition and differentiating between contrasting mother nerve disorders followed by subsequent treatment seems to be the frontier in Parkinson’s therapy.

Causes and symptoms:

Parkinson’s disorder results from neurons in the brain gradually dissimilating over time or dying. These neurons are responsible for chemical interactions between the brain and other body organs, with dopamine as the chemical neurotransmitter. When the levels of dopamine decrease, it results in abnormal brain activity and the nerve connected organs misbehave as a result, owing to a range of characteristic symptoms seen during Parkinsonian attacks.

The causes of Parkinson’s are still unknown, however many factors attribute to how the disease acts up. These include:

• Certain genes:
   Researchers have identified certain genetic mutations in genes that result in Parkinson’s disease. These are however, quite rare and can be seen more commonly in family members with a history of Parkinson’s. The variant genetic markers present a small risk of acquiring Parkinson’s, nonetheless, are important in a minute number of cases.
• Epigenetic factors:
   These are environmental triggers that may have an effect on the genetic makeup of the cell. Exposure to certain toxins may increase risks of Acquiring Parkinson’s at later stages of life; although, the chances are quite rare.
• Lewy bodies:
   Researchers have seen many changes occur in brains of patients suffering from the ailment, however, why or what causes these changes still appears unknown. Clumps of substances that rise up following Parkinson’s can be seen as markers of the disease. These are called Lewy bodies, and many scientists believe these could hold an important position in early diagnosis of the disease.
• Alpha-synuclein:
   There are many particles found inside Lewy bodies, however, one important one is the natural and overly expressed protein called Alpha-synuclein. These causes the cells to clump together that the body cannot break down, researched extensively nowadays as scientists believe it could hold clues to the cause of Parkinson’s.

Parkinson’s may result in a number of symptoms, some generalised, while others found isolated in some patients but not in others. Early signs may present subtly, and go unnoticed in many cases. Symptoms often start on one side of the body and usually become worse on that side, even when other side is also affected. Early diagnosis of these symptoms can not only aid in treatment but halt progression to some extent. These symptoms include:

• Tremors:
   Consistent shaking or trembling usually begins in one of the limbs, more commonly hands or fingers. Patients often notice a to and fro rubbing of the thumb and forefinger, known as pill rolling tremor. The diagnostic characteristic tremor pf Parkinson’s is a tremor of the hand when it is relaxed or resting, in contrast with tremor present by Essential tremor during periods of activity.
• Bradykinesia:
   Bradykinesia refers to slowed movement that occurs over time. Parkinson’s reduces the ability to move and slurs movement, making daily and simple tasks bothersome and time consuming. Patients find their steps become shorter when walking, or it may take more time to get out of the chair than before. Dragging the feet while walking, as picking up the feet might take more energy, is also fairly common in patients.
• Muscle rigidity:
   stiffness and tensed muscles occur in any part of the body. The inflexible muscle movement causes severe pain and limits range of motion even more.
• Impaired posture and balance irregularity:
   For most patients, the posture may become stooped, due to balance problems associated with the brain connection. Patients often find it difficult to maintain balance while walking.
• Loss of automatic movements:
   Certain automatic movements such as blinking, smiling, swinging of the arms when walking and reflex actions may become slowed or lose entirely. The ability to perform unconscious movements in most patients decrease considerably.
• Speech impairment: Patients often complain of speech problems as a result of Parkinson’s disorder. Individuals may speak more softly, quickly, slur or waver before talking. The speech may often become monotonous instead of usual inflections.
• Writing changes:
   With the tremor in hand, writing may become very hard. The writing may also become smaller and smaller as the patient writes on a piece of paper.

A patient is advised to see a doctor if the symptoms get out of hand, worsen suddenly or new symptoms arise. A movement specialist will diagnose your condition after early symptoms, rule out other causes, and prescribe the right medicine for treating the condition.

Diagnosis and treatment:

There are actually no specific tests to diagnose Parkinson’s disease. A physician trained in nervous system condition (neurologist) will diagnose Parkinson’s based on the following:

• Medical history:
   Patients with a medical history of Parkinsonian symptoms may be at risk of acquiring the disease at later stages.
• Signs and symptoms:
   The doctor examines the signs and symptoms present and differentiate them from overlapping symptoms of other common movement disorders.
• Neurological and physical examination:
   This may provide extra clues into your diagnosis.
• Other tests:
   The doctor may also order other tests such as blood tests to rule out other conditions, such as infections, that may be causing your symptoms;
• Imaging tests:
   Brain imaging tests such as MRI, ultrasound of the brain, SPECT and PET scans, may also be utilized to help rule out other conditions. Imaging tests are not necessarily helpful when diagnosing Parkinson’s disease.

In addition to this examination, the doctor may also prescribe Carbidopa-levodopa, which is a Parkinson’s disease medicine. With sufficient doses, patients showing benefit are presented with a confirmed diagnosis of Parkinson’s disease. It may also take time to diagnose the proper disorder and the doctor may often order follow ups in the future to evaluate the treatment plan.

There are many medicines in the market that can help control Parkinson’s symptoms. Doctors often recommend certain lifestyle changes and physical therapy that may benefit the patient in the long run. Typical treatment options include the following:

Medications:

People with Parkinson’s have low dopamine concentrations, however, dopamine infused medicines cannot be injected directly as they cannot enter the brain. More over these medicines may lose efficiently over time; however, they present the mainstay of treatment and help manage problems with walking, movement and tremors. These include the following:

• Carbidopa-levodopa: This has become the most effective Parkinson’s medicine. It is natural and passes to the patient’s brain converting into dopamine. Levodopa combined with carbidopa to protect from premature conversion outside the brain, as well as prevent troublesome side effects such as nausea. The benefits of levodopa however, wane off after years and may cause side effects such as involuntary shaking after high doses.
• Carbidopa-levodopa infusion: The US food and drug administration (FDA) recently approved Duopa in 2015. It is administered through a feeding tube and enters directly into blood stream through small intestine, which also causes its levels to remain constant for a longer time.
• Dopamine agonists: these do not change into dopamine, but rather mimic dopamine effects in the brain. They are not as effective, yet, they last longer in the blood. Some Side effects include hallucinations, sleepiness and compulsive behaviors. Dopamine agonists include Pramipexole(Mirapex) and Rotigone amongst others.
• MAO-B inhibitors: these prevent breakdown of brain dopamine by inhibiting enzyme monoamine oxidase B (MAO-B). Side effects include hallucinations and insomnia, and are often restricted when using antidepressants.
• Anticholinergics: these medications have been used for many years to control Parkinson’s. They include Benztropine and trihexyphenidyl.
• Amantadine: this medicine provides short term relief of symptoms and given during later stages to prevent involuntary movements induced by carbidopa-levodopa. Purple mottling of the skin is a common side effect

Surgical procedures:

This may be done in advanced cases and in case medications do not control symptoms, they include the following:

• Deep brain stimulation: this includes implanting an electrode into the brain that sends electrical pulses to the brain, and reduces Parkinson’s symptoms. Surgery involves certain risks such as hemorrhage and stroke. DBS can stabilize medication fluctuations or halt the involuntary movements due to Carbidopa-levodopa, as well as reduce tremor, rigidity and improve slow movement. It can also be helpful against erratic and fluctuating responses from other medication. However DBS is often not helpful for problems that do not respond to levodopa therapy apart from tremors.

At the moment, DBS seems to be the most effective treatment following carbidopa-levodopa, although like the latter, it does not keep Parkinson’s symptoms from progressing. It can nonetheless provide sustained benefit for Parkinson’s symptoms.

Further venturing into Parkinson’s research is important to discover novel treatment options that will overcome the progressive nature of the disease, or even eradicate it from grass root level. The coming years will provide a plethora of research for this debilitating and incapacitating disorder.

References:

http://www.ninds.nih.gov/disorders/parkinsons_disease/parkinsons_disease.htm

http://www.mayoclinic.org/diseases-conditions/parkinsons-disease/basics/definition/con-20028488

https://www.nlm.nih.gov/medlineplus/parkinsonsdisease.html