Parkinson's disease: Causes, Symptoms, Diagnosis, Treatment & Prevention

 

Parkinson's disease is an age-related degenerative brain condition that causes regions of the brain to degenerate. It is well known for generating delayed movements, tremors, and balance issues. Most cases occur for unknown reasons, while some are inherited. The condition is incurable;  however, there are numerous options for treatment

Parkinson's disease is a progressive nervous system movement illness. The nervous system is a network of nerve cells that regulates several aspects of the body, including movement.

Symptoms appear slowly. The first sign may be a barely noticeable tremor in one hand, or occasionally in the foot or jaw. Tremors are common in Parkinson's disease. However, the disease can induce stiffness, slowness of movement, and balance problems, all of which raise the risk of falling.

In the early stages of Parkinson's disease, your face may have little to no expression.  Your arms may not swing when you walk.  Your speech may become softer or slurred.  Symptoms worsen over time.

 Although Parkinson's disease cannot be cured, medications may help improve symptoms.  Sometimes a healthcare expert may recommend surgery to assist managing certain portions of the brain.  The surgery may help alleviate discomfort.

Also Read: Brain diseases: Types, Causes, Symptoms, Diagnosis, Treatment & Prevention

What is Parkinson's Disease?

Parkinson's disease is a condition in which a section of your brain deteriorates, resulting in increasingly severe symptoms over time. While this disorder is best known for affecting muscle control, balance, and mobility, it can also have a variety of additional consequences on your senses, thinking ability, mental health, and so on.

Symptoms:

Parkinson's disease symptoms might be unique to each individual. Early signs may be mild, and you may not notice them. Symptoms frequently appear on one side of the body before spreading to the other. Symptoms can be worse on one side than the other. Some Parkinson's disease symptoms are similar to those of other disorders.

Parkinson's symptoms can include:

• Tremor. The rhythmic shaking typically begins in the hands or fingers. Tremors can originate in the foot or jaw. You can rub your thumb and forefinger back and forth. This is referred to as a pill-rolling tremor. Your hand may quiver at rest or when you are stressed. You may notice that you shake less as you perform a chore or move about.

• Slowed movement, commonly known as bradykinesia. Parkinson's disease can slow your movement and make routine things more challenging. It may be difficult to move out of a chair, shower, or get dressed. You may have less expression on your face. It may be hard to blink.

• Rigid muscles. You could have stiff muscles in any portion of your body. Your muscles may feel tense and painful, and your arm movements may be brief and jerky.

• Poor posture and balance. Your posture may slump. You may fall or experience balance issues.

• Loss of automatic movement. You may be unable to perform some actions that you normally do without thinking, such as blinking, smiling, or swinging your arms while walking.

• Speech changes.  You can speak quietly or fast, slur, or pause before speaking.  Your speech may be flat or monotone, lacking in regular speech patterns.

•  Writing changes.  You may have difficulty writing, and it may appear cramped and small.

•  Non-motor symptoms.  Depression, anxiety, constipation, and sleep issues are all possibilities.  They may also include acting out nightmares, frequent urination, difficulty smelling, cognitive and memory issues, and severe tiredness.

Causes:

Parkinson's disease is caused by the gradual breakdown or death of nerve cells in the brain known as neurons. Many Parkinson's disease symptoms are produced by the death of neurons that produce a chemical messenger in the brain. This messenger's name is dopamine.

Decreased dopamine levels cause irregular brain activity. This causes mobility issues as well as other Parkinson's disease symptoms. People with Parkinson's disease also lose norepinephrine, a chemical messenger that regulates numerous body systems, including blood pressure.

The cause of Parkinson's disease is unknown; however, various factors appear to have a role.

Genes. Parkinson's disease is thought to be caused by specific genetic abnormalities. However, these are uncommon unless several family members have Parkinson's disease.
Environmental considerations. Certain chemicals and other environmental variables may raise the likelihood of developing Parkinson's disease later in life. One example is MPTP, a chemical present in illegal substances and occasionally sold as "synthetic heroin." Other examples are herbicides and drinking water from wells. However, no single environmental factor has been proven as a cause.

Many alterations occur in the brains of people with Parkinson's.  Researchers are investigating why these changes occur and what functions they play. These changes include:

• The presence of lewy bodies. Parkinson's disease is linked to protein clumps in the brain. These proteins are known as Lewy bodies, and experts believe they hold significant clues to the cause of Parkinson's disease.

• Alpha-synuclein is present in Lewy bodies. Alpha-synuclein is a protein that appears in all Lewy bodies. It exists in a clumped state that cells cannot break down. This is currently a key topic for Parkinson's disease researchers. Alpha-synuclein has been identified in the spinal fluid of those who develop Parkinson's disease.

• The mitochondria are altered. Mitochondria are powerful compartments within cells that produce the majority of the body's energy. Changes to the mitochondria might induce cell harm. These abnormalities have been observed in the brains of those with Parkinson's disease.

Risk Factors:

The risk factors for Parkinson's disease are:

• Age. The chance of Parkinson's disease increases with age. It usually begins at age 50 or older. The typical age of onset is roughly 70. Parkinson's disease can develop in young adults, but it is uncommon. Early-onset Parkinson's disease occurs when a person is younger than 50 years old.

• Genetics. Having a first-degree family member with Parkinson's disease, such as a parent or sibling, increases your risk. Unless you have a large number of blood relatives with the illness, your risk remains low.

• Male sex. Men are more prone to developing Parkinson's disease than women.

• Toxic exposure. Continuous exposure to herbicides and pesticides may modestly raise your risk of Parkinson's disease.

Complications:

People with Parkinson's disease may experience additional consequences that are treatable. This may include:

• Trouble thinking clearly. Parkinson's disease can impair one's memory, language, and cognitive abilities. The disease can potentially cause dementia and other cognitive impairments. These consequences typically appear later in Parkinson's disease, and medications have only a moderate impact in controlling these symptoms.

• Emotional changes and depression. Some people may get angry and anxious early in Parkinson's disease. They may also be depressed or anxious. Medicines and other treatments can assist with these changes.

• Trouble swallowing and chewing. Parkinson's disease in its latter stages affects the muscles of the mouth. This creates difficulty swallowing and chewing, which can lead to insufficient nutrient intake. Choking or drooling can result from the accumulation of food or saliva in the oral cavity.

• Sleep issues and disorders. You may wake up frequently at night, experience nightmares, and fall asleep throughout the day.

Another sign could be rapid eye movement sleep behavior disorder. This entails acting out your dreams. Medicines and other therapies may improve your sleep quality.

Additional symptoms that may develop include:

Bladder problems. You may experience difficulties such as urgency.

• Constipation. You may have difficulty passing stool. You may pass stool less than three times each week.

• Blood pressure changes. Standing up may cause you to feel dizzy, lightheaded, or faint due to a fast drop in blood pressure. This is also known as orthostatic hypotension.

• Loss of scent. You may completely or partially lose your ability to smell.

• Tiredness. You may feel exhausted and lack energy, particularly late in the day.

• Pain. Your muscles and joints may be in discomfort or cramping.

• Sexual symptoms. You may experience decreased sexual desire or performance.

How is it diagnosed?

Parkinson's disease diagnosis is primarily a clinical process, which requires a healthcare expert to examine your symptoms, ask questions, and check your medical history. Some diagnostic and laboratory tests are available;  however, they are often used to rule out other illnesses or causes.

However, most lab tests are unnecessary unless you do not respond to Parkinson's disease treatment, which may indicate the presence of another condition.

What tests will be performed to diagnose this condition?

When healthcare providers suspect Parkinson's disease or need to rule out other conditions, they might use several imaging and diagnostic procedures. This includes:

• Blood tests (may help rule out other types of Parkinsonism).

• A computed tomography (CT) scan.

• Genetic testing.

• Magnetic resonance imaging, or MRI.

• A positron emission tomography (PET) scan.

New laboratory testing is possible.

Researchers have discovered potential diagnostic indications for Parkinson's disease. Both of these new techniques detect the alpha-synuclein protein in novel and unique ways. While these tests cannot tell you what problems you have due to misfolded alpha-synuclein proteins, they can assist your doctor reaching a diagnosis.

The two tests employ the following methodologies.

• A spinal tap. One of these tests looks for misfolded alpha-synuclein proteins in the cerebrospinal fluid, which surrounds the brain and spinal cord. This test includes a spinal tap (lumbar puncture), in which a healthcare provider inserts a needle into your spinal canal to collect cerebrospinal fluid for testing.

• Skin biopsies.  Another possible test is a surface nerve tissue biopsy.  A biopsy involves taking a small sample of your skin, including the nerves.  The samples are taken from one area on your back and two on your legs.  Analyzing the samples can help identify whether your alpha-synuclein has a specific defect that increases your risk of developing Parkinson's disease.

Treatment:

How is it treated, and is there a cure?

Parkinson's disease is currently incurable, but there are numerous treatments available to alleviate symptoms. Treatment options can also differ from person to person, based on their individual symptoms and how well various treatments work. Medications are the primary treatment for this condition.

A further therapy option is surgery to implant a device that delivers a small electrical current to a specific area of your brain. There are some experimental possibilities, such as stem cell-based therapy, but their availability varies greatly, and many are not available to persons with Parkinson's disease.

What medications and treatments are administered?

Medication treatments for Parkinson's disease are divided into two categories: direct treatments and symptom treatments. Direct treatments are designed to address Parkinson's disease directly. Symptom therapies only address particular aspects of the disease.

Medications

 Parkinson's disease medications address the condition in a variety of ways.  As a result, medicines that perform any of the following are most likely:

•  Adding dopamine.  Medications such as Levodopa can boost the amount of dopamine in your brain.  This medicine is almost always effective, and when it fails, it is usually due to a different type of Parkinsonism than Parkinson's disease.  Long-term usage of Levodopa has side effects that lesson its effectiveness.

• Simulating dopamine. Dopamine agonists are medications that provide dopamine-like effects. Dopamine is a neurotransmitter that causes cells to function in a specific way when a dopamine molecule attaches to them. Dopamine agonists can bind to cells and cause them to act similarly. Younger people are more likely to delay starting levodopa.

• Dopamine metabolism blockers. Your body has natural processes for breaking down neurotransmitters such as dopamine. Medications that prevent your body from breaking down dopamine make more dopamine available to your brain. They are notably useful early on and can be taken with levodopa in the later stages of Parkinson's disease.

• Levodopa metabolism inhibitors. These treatments slow down the way your body absorbs levodopa, allowing it to last longer. These drugs should be used with caution because they can be poisonous and cause liver damage. They are typically used to supplement levodopa when it loses efficacy.

• Adenosine blockers. When used in conjunction with levodopa, medications that inhibit how particular cells use adenosine (a chemical found in many different forms throughout your body) can have a beneficial effect.

Several medications target specific Parkinson's disease symptoms. Symptoms treated commonly include the following:

•  Sexual dysfunction

• Fatigue or drowsiness

• Constipation

• Sleep issues

• Depression

• Dementia

• Anxiety

Hallucinations and other psychotic symptoms.

Deep Brain Stimulation

In the past, surgery was used to intentionally damage and scar a section of your brain that was malfunctioning due to Parkinson's disease. Today, deep-brain stimulation can achieve the same effect by delivering a modest electrical current to the same locations via an implanted device.

The primary advantage is that deep brain stimulation is reversible, whereas intentional scarring damage is not. This treatment option is virtually always a possibility in the late stages of Parkinson's disease, when levodopa therapy is less successful, and in those who have tremors that do not appear to react to medications.

Experimental treatments

Researchers are looking into different possible treatments for Parkinson's disease. While not generally available, they do provide hope to those suffering from this ailment. Some of the experimental therapy techniques are:

• Stem cell transplantation. These introduce new dopamine-using neurons into your brain to replace destroyed ones.

• Neuron repair treatment. These treatments aim to heal damaged neurons while also encouraging new neurons to develop.

• Gene therapies and gene-specific treatments. These medicines target the particular mutations that cause Parkinson's disease. Some also improve the efficacy of levodopa and other treatments.

Possible complications or negative effects from treatments.

The difficulties and side effects associated with Parkinson's disease treatments are determined by the medications themselves, the severity of the condition, any other health conditions you may have, and more. Your healthcare professional is the best person to tell you about the potential side effects and consequences. They can also advise you on how to reduce the impact of these side effects or difficulties in your life.

More on Levodopa.

Levodopa is the most commonly prescribed and successful medication for Parkinson's disease. While this medicine has significantly improved Parkinson's disease treatment, physicians use it with caution due to how it works. They may also prescribe other medications to enhance the efficacy of Levodopa or to alleviate side effects and symptoms.

Levodopa is frequently coupled with other medications to prevent your body from digesting it before it reaches your brain. This helps to prevent other dopamine adverse effects, such as nausea, vomiting, and low blood pressure when standing (Orthostatic hypotension).

The way your body uses Levodopa varies over time, and it may lose effectiveness. Increasing your dose can assist, but it also increases the likelihood and severity of adverse effects, and the amount can only go so high before becoming hazardous.

Prevention:

Because the cause of Parkinson's disease is unknown, there are no proven prevention methods. According to research, several variables may help prevent it. But scientists don't know for certain. These factors include:

• Exercise. Aerobic exercise has been associated with a reduced risk of Parkinson's disease.

• Caffeine. Some studies link drinking caffeinated beverages like coffee and green tea to a lower incidence of Parkinson's disease.

• Medicines. Some medications, including ibuprofen and statins, have been associated to a reduced risk of this disease.

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