Parkinson's Disease

Parkinson's disease is a common condition of the brain that typically begins in the middle to later part of life. It is a progressive condition, meaning that it continues to get worse with time. Parkinson's disease has probably existed for thousands of years. Its symptoms and potential therapies were mentioned in the Ayurveda (the system of medicine practiced in India as early as 5000 B.C.) and in the first Chinese medical text (Nei Jing), which appeared 2,500 years ago.

Parkinson's disease occurs when certain nerve cells (called neurons) in an area of the brain known as the substantia nigra die or become impaired. Normally, these neurons produce an important brain chemical known as dopamine. Dopamine is a chemical messenger responsible for transmitting signals between the substantia nigra and the next "relay station" of the brain, the corpus striatum, to produce smooth, purposeful muscle movement.

A loss of dopamine causes the nerve cells of the corpus striatum to fire out of control, leaving people unable to direct or control their movements in a normal manner. Parkinson's research studies have shown that people with the condition have lost 80 percent or more of the dopamine-producing cells in the substantia nigra.

But why this nerve death or impairment happens is still unknown, although significant findings by research scientists continue to yield fascinating new clues and several theories about Parkinson's disease causes.

Current Theories for the Cause of Parkinson's Disease

Current theories regarding the cause or causes of Parkinson's disease include:

• Environmental factors
• Genetic factors
• Free radicals
• Normal age-related wearing down
• A combination of some or all of these theories.

Common Parkinson's Disease Symptoms

Common Parkinson's disease symptoms include:

• Tremors
• Rigid limbs
• Slow movement (bradykinesia)
• A shuffling gait
• An inability to move (akinesia)
• A stooped posture
• Reduced facial expressions
• A soft speaking voice.

Tremors

Tremors are one of the most common symptoms of the disease. The tremor associated with the condition has a characteristic appearance. Typically, it takes the form of a rhythmic back-and-forth motion of the thumb and forefinger at three beats per second. This is sometimes called "pill rolling." Tremors usually begin in a hand, although sometimes, a foot or the jaw is affected first. It is most obvious when the hand is at rest or when a person is under stress. In three out of four people, the tremor may affect only one part or side of the body -- especially during the early stages of the disease. Later it may become more general. Tremors are rarely disabling, and they usually disappear during sleep or improve with intentional movement.

Rigidity

Rigidity, or a resistance to movement, is aParkinson's disease symptom seen in most people with this condition. A major principle of body movement is that all muscles have an opposing muscle. Movement is possible, not just because one muscle becomes more active, but also because the opposing muscle relaxes. In Parkinson's disease, rigidity comes about when, in response to signals from the brain, the delicate balance of opposing muscles is disturbed. The muscles remain constantly tensed and contracted so that the person aches or feels stiff or weak. The rigidity becomes obvious when another person tries to move the affected person's arm, which will move only in ratchet-like or short, jerky movements known as "cogwheel" rigidity.

Bradykinesia

Bradykinesia, or the slowing down and loss of spontaneous and automatic movement, is a particularly frustrating symptom of Parkinson's disease because it is unpredictable. One moment the person can move easily. The next moment, he or she may need help. This may well be the most disabling and distressing symptom of the disease because the person cannot rapidly perform routine movements. Activities once performed quickly and easily -- such as washing or dressing -- may take several hours.

Postural Instability

Postural instability, or impaired balance and coordination, causes a person to develop a forward or backward lean and to fall easily. When bumped from the front or when starting to walk, a person with a backward lean has a tendency to step backwards, which is known as retropulsion.

Postural instability can cause a person to have a stooped posture, in which the head is bowed and the shoulders are drooped. As the disease progresses, walking may be affected. A person may halt in mid-stride and "freeze" in place, possibly even toppling over. Or, he or she may walk with a series of quick, small steps as if hurrying forward to keep balance. This is known as festination.

Other symptoms of Parkinson's disease can include:

• Depression
• Emotional changes
• Dementia
• Difficulty swallowing and chewing
• Speech impairments
• Urinary problems
• Constipation
• Skin problems
• Sleep disturbances
• Sexual difficulties.

Depression

Depression is a common problem and may appear early in the course of the disease, even before other symptoms are noticed. Depression may not be severe, but it may be intensified by the drugs used to treat other Parkinson's disease symptoms. Fortunately, depression can be successfully treated with antidepressant medications.

Emotional Changes

Some people with Parkinson's disease become fearful and insecure. Perhaps they fear they cannot cope with new situations. They may not want to travel, go to parties, or socialize with friends. Some lose their motivation and become dependent on family members. Others may become irritable or uncharacteristically pessimistic. Memory loss and slow thinking may occur, although the ability to reason remains intact. Whether people actually suffer intellectual loss (also known as dementia) from Parkinson's disease is a controversial area still being studied.

Difficulty With Swallowing and Chewing

The muscles used in swallowing may work less efficiently in later stages of Parkinson's disease. In these cases, food and saliva may collect in the mouth and back of the throat, which can result in choking or drooling. Medications can often alleviate these problems.

Speech Changes

About half of all people with Parkinson's disease have problems with speech. They may speak too softly or in a monotone voice, hesitate before speaking, slur or repeat their words, or speak too fast. A speech therapist may be able to help these people reduce some of these problems.

Urinary Problems or Constipation

In some people with Parkinson's disease, symptoms affecting the bladder and bowel can occur due to the improper functioning of the autonomic nervous system. The autonomic nervous system is responsible for regulating smooth muscle activity. Some people may become incontinent, while others have trouble urinating.

Others may experience constipation because the intestinal tract operates more slowly. Constipation can also be caused by inactivity, eating a poor diet, or drinking too little fluid. It can be a persistent problem and, in rare cases, can be serious enough to require hospitalization. People should not let constipation last for more than several days before taking steps to alleviate it.

Skin Problems

In Parkinson's disease, it is common for the skin on the face to become oily, particularly on the forehead and at the sides of the nose. The scalp may become oily, too, resulting in dandruff. In other cases, the skin can become quite dry. These problems are also the result of an improperly functioning autonomic nervous system. Standard treatments for skin problems can be help helpful. Excessive sweating, another common symptom, is usually controllable with the medications used forParkinson's disease treatment.

Sleep Problems

Parkinson's disease symptoms can also include sleep problems. These include difficulty staying asleep at night, restless sleep, nightmares and emotional dreams, and drowsiness during the day. It is unclear if these symptoms are related to the disease or to the medications used to treat Parkinson's disease. People with Parkinson's should never take over-the-counter sleep aids without consulting their healthcare providers.

Stages of Parkinson's Disease

Stage I (Beginning Stage of Parkinson's)

Stage I is considered the beginning stage of the disease. A person is categorized with stage I if the following are present:

• Signs and symptoms are only on one side of the body
• Symptoms are mild
• Symptoms are inconvenient but not disabling
• Usually has tremors in one limb
• Friends have noticed changes in posture, locomotion, and facial expression.

Stage I is also known as early-stage Parkinson's disease.

Parkinson's Disease Stage II

A person is categorized as stage II if the following are present:

• Symptoms occur on both sides of the body
• Minimal disability
• Posture and gait are affected.

Parkinson's Disease Stage III (Moderate Parkinson's Disease)

Stages III, IV, and V are when a person develops significant disability from Parkinson's disease. A person in stage III is considered to have moderate Parkinson's disease.

A person is categorized with stage III if the following are present:

• Significant slowing of body movements
• Early impairment of equilibrium when walking or standing
• Generalized dysfunction that is moderately severe.

Stage IV (Advanced Parkinson's Disease)

A person is categorized with stage IV of the disease if the following are present:

• Severe symptoms
• The person can still walk to a limited extent
• Rigidity and bradykinesia are present
• Person is no longer able to live alone
• Tremor may be less than earlier stages.

This stage is considered advanced Parkinson's disease.

Stage V Parkinson's Disease

A person is said to be in stage V if the following are present:

• Cachectic stage (general reduction in vitality and strength of body and mind)
• Invalidism complete
• Person cannot stand or walk
• Requires constant nursing care.

Diagnosing Parkinson's Disease

Parkinson's disease may be difficult for healthcare providers to diagnose because early symptoms may be vague, and they can mimic other conditions or even be dismissed as normal aging.

In order to make a Parkinson's disease diagnosis, a healthcare provider will begin by asking a number of questions (known as a medical history). Some of these may include questions about:

• Your current symptoms
• Other medical conditions you have
• Medications you may be taking.

He or she will also perform a physical exam to look for signs and symptoms of Parkinson's disease.

Tests and Procedures for Diagnosing Parkinson's Disease

Parkinson's disease can also be hard to diagnose early on because there are no tests or procedures that can definitely diagnose the condition. Your healthcare provider may recommend several tests and/or procedures to help rule out other conditions that can cause similar symptoms. This may involve blood tests or a brain scan. However, brain scans (such as a CT scan or an MRI) generally appear normal in a person with Parkinson's disease.

Is the Diagnosis Parkinson's Disease or Another Condition?

Several medical conditions can share similar symptoms with Parkinson's disease, especially during the early stages. Your healthcare provider will consider these before making a Parkinson's disease diagnosis.

Some of these conditions fall under a group of disorders with similar features called Parkinson syndromes, or parkinsonism. These disorders share several symptoms, and all are the result of the loss of dopamine-producing brain cells. Parkinson's is also called primary parkinsonism or idiopathic Parkinson's disease. Idiopathic is a term describing a disorder for which no cause has yet been found. In the other forms of parkinsonism, either the cause is known or suspected, or the disorder occurs as a secondary effect of another, primary neurological disorder.

Besides Parkinson's disease, other forms of parkinsonism include:

• Postencephalitic parkinsonism
• Drug-induced parkinsonism
• Striatonigral degeneration
• Ateriosclerotic parkinsonism
• Toxin-induced parkinsonism (such as carbon monoxide or cyanide)
• Lewy body dementia
• Accompanying other conditions, such as:

• Shy-Drager syndrome (sometimes called multiple system atrophy)
• Progressive supranuclear palsy
• Wilson's disease
• Huntington's disease
• Hallervorden-Spatz syndrome
• Alzheimer's disease
• Creutzfeldt-Jakob disease
• Olivopontocerebellar atrophy
• Post-traumatic encephalopathy.

Parkinson's Disease Treatment

Currently, there is no cure for Parkinson's disease. Also, there is no treatment that has been shown to slow down or stop the progression of the disease. However, there is treatment for Parkinson's disease that provides dramatic relief from the symptoms.

Before recommending a specific treatment, your healthcare provider will consider several factors, including your:

• Current Parkinson's disease symptoms, along with how much the symptoms disrupt your life
• Mental and emotional state
• Current medications.

Based on these factors, your healthcare provider will recommend one or several different treatment options. Some of these treatment options can include:

• Medications
• Lifestyle changes and support
• Surgery.

Medications for Treating Parkinson's Disease

Not everyone who is diagnosed with Parkinson's disease will immediately require medicine. Many people are only mildly affected and do not require medications for several years after the initial diagnosis.

When Parkinson's treatment does become necessary, healthcare providers often begin with one or more of the less powerful Parkinson's disease medications. This includes such drugs as:

• Selegiline (Eldepryl^®, Zelapar^®, Emsam^®)
• An anticholinergic
• A dopamine agonist, such as pramipexole (Mirapex^®) orropinirole (Requip^®).

This allows healthcare providers to save the most powerful treatment (specifically, levodopa) for the time when people need it most.

When Parkinson's disease symptoms become severe, healthcare providers usually prescribe levodopa combined with carbidopa. Carbidopa-levodopa products are available as the brand-name medicinesSinemet^®, Sinemet^® CR, Parcopa^®, or as a generic. Carbidopa is used with levodopa because it delays the conversion of levodopa into dopamine (a chemical messenger) until it reaches the brain. Nerve cells can use levodopa to make dopamine and replenish the brain's dwindling supply of this neurotransmitter.

Lifestyle Changes and Support Groups

Lifestyle changes are an important part of any treatment for Parkinson's disease. This includes exercise and diet. Support groups also can be helpful.

Exercise

Because movements are affected in Parkinson's disease, exercising may help people improve their mobility. Some healthcare providers prescribe physical therapy or muscle-strengthening exercises as a part of Parkinson's disease treatment. This is intended to tone muscles and to put underused and rigid muscles through a full range of motion. Exercises will not stop Parkinson's disease from progressing, but they may improve body strength so that the person is less disabled.

Exercises also improve balance, helping people overcome gait problems, and can strengthen certain muscles so that people can speak and swallow better. Physical activity can also improve the emotional well-being of people with Parkinson's by giving them a feeling of accomplishment.

Although structured exercise programs help many people, more general physical activity is also beneficial. Some examples include:

• Walking
• Gardening
• Swimming
• Calisthenics
• Using exercise machines.

Diet

Eating a well-balanced, nutritious diet can be beneficial for anybody. However, to prevent or cure Parkinson's disease, there does not seem to be any specific vitamin, mineral, or other nutrient that has any therapeutic value for Parkinson's disease treatment. In fact, a high-protein diet may limit the effectiveness of levodopa.

Despite some early optimism, recent studies have shown that tocopherol (a form of vitamin E) does not delay Parkinson's disease. This conclusion came after a carefully conducted, five-year study that examined the effects of both selegiline and vitamin E on early symptoms of Parkinson's disease. While selegiline was found to slow down the early progression of the disease and delay the need for levodopa, there was no evidence of any therapeutic benefit from vitamin E.

Support Groups

One of the most demoralizing aspects ofParkinson's disease is how completely a person's world changes. The most basic daily routines may be affected -- from socializing with friends and enjoying normal and congenial relationships with family members, to earning a living and taking care of a home. Faced with a very different life, people need encouragement to remain as active and involved as possible. That's when support groups can be a valuable part of Parkinson's disease treatment, not only to the person affected, but to their families and caregivers as well.

Surgery as a Part of Treatment

Surgery for Parkinson's disease was once a common practice. However, after the discovery of levodopa, surgery was restricted to only a few cases. Currently, surgery is reserved for people who have failed to respond satisfactorily to drugs.

One of the procedures used as part of Parkinson's disease treatment, called cryothalamotomy, requires a supercooled metal probe tip to be surgically inserted into the thalamus (a "relay station" deep in the brain). This destroys the area of the brain that produces tremors. This and related procedures, such as thalamic stimulation, are coming back into favor for people who have severe tremors or have Parkinson's only on one side of the body.

A therapy called deep brain stimulation (DBS) has now been approved by the U.S. Food and Drug Administration (FDA) for treating Parkinson's disease. In DBS, electrodes are implanted into the brain and connected to a small electrical device, called a pulse generator, that can be externally programmed. DBS can reduce the need for levodopa and related drugs, which, in turn, decreases the involuntary movements (dyskinesias) that are a common side effect of levodopa. It also helps to:

• Alleviate fluctuations of symptoms
• Reduce tremors, slowness of movements, and gait problems.

DBS requires careful programming of the stimulator device in order to work correctly.

Parkinson's Disease Research

There has been considerable progress made within Parkinson's research in recent years. Ongoing studies aim to discover better ways of relieving the symptoms of Parkinson's disease and ultimately preventing or halting the disease. New Parkinson's disease research is focusing on many areas, including brain anatomy, dopamine, environmental factors, genetics, mitochondria, and cell transplantation.