Parkinson's Disease

Description What Is Parkinson's Disease?

Parkinson's Disease is a chronic progressive nervous disease that is linked to decreased dopamine production in the substantia nigra (a layer of deeply pigmented gray matter situated in the midbrain and containing cell bodies of a tract of dopamine-producing nerve cells). It is marked by tremor, weakness of resting muscles, and by a shuffling gait. The disorder is named for British Physician James Parkinson, who first described the disease in a report called "An Essay on the Shaking Palsy", in 1817. Parkinson called the disorder paralysis agitans; Latin words meaning "shaking palsy".

Dopamine is a neurotransmitter, a chemical that carries messages from one nerve cell to another. Loss of dopamine disrupts the communication pathways among the nerves that help control movement. Symptoms of Parkinson's may cause problems with walking or talking and sometimes may produce severe disabilities. Scientists do not know the cause of Parkinson's disease, and while there is no cure there are various treatments and therapies that may alleviate some of the more troubling symptoms.

Parkinson' disease occurs in people worldwide, however the incidence is higher in men than in women, and Caucasians have a higher incidence than people of other races. In the United States and Canada more than 50,000 people are diagnosed with the disease each year. It is hard to estimate how many people have the disease, however, as the symptoms are often mistaken for the normal effects of aging, or are believed to be caused by other diseases. It most commonly develops around the age of 60, and the incidence rises with age. At least ten percent of cases occur in people under the age of forty, and there is a rare form that affects teenagers.

Signs and Symptoms

Motor Problems

For the motor disorders, the four classic symptoms that Health Care Providers look for in assessing a person that is suspected of having Parkinson's are:

Tremor (the involuntary shaking of limbs): Tremor often starts with the slight shaking in one hand that later spreads to the entire arm. In the beginning, tremors sometimes cause the hand to rub back and forth between thumb and forefinger (this is called pin rolling). Tremors may also develop in the head, lips or feet. These symptoms may occur on one or both sides of the body, and while they can be distressing, they are not usually disabling, and generally disappear during sleep. At least a third of people diagnosed with the disease do not develop this symptom.

Rigidity (stiffness of limbs and joints): Rigidity usually occurs in the limbs and the neck. The stiffness in the joints is similar to arthritis. Often rigidity impairs the small muscles of the hands, making tasks such as buttoning a shirt, writing, or typing difficult.

Bradykinesia (generalized slowness of movements): this is the most debilitating symptom and produces a physical and mental sluggishness. The slowness in the voluntary movements contributes to varied problems, such as a distinctive shuffling walk, stooped posture, indecipherable handwriting, and even simple tasks become difficult and time consuming. The slowness in the speech patterns makes communication difficult and frustrating for not only the patient but also for the patient's friends and family. In the later stages of the disease, the muscles may freeze up, making it difficult to resume normal movement. This sluggishness may also affect the digestive tract and can contribute to constipation, which is often a major problem for people with Parkinson's.

Postural Instability (difficulty adjusting to changes in body positions): This impaired reflex appears as unsteadiness or lack of balance and contributes to falls and injuries for people with Parkinson's. A person without Parkinson's who trips and starts to fall is usually able to quickly move the trunk and limbs in such a way as to prevent or ease the fall. People with postural instability, on the other hand, are unable to respond as quickly, and cannot move in a way that stops or lessens their fall. Often just simple turning, or rising from a chair are difficult and can result in an imbalance that can lead to falling.

Symptoms usually affect one side of the body more than the other side and there are always two primary symptoms present when a diagnosis of Parkinson's is made.

According to the Hoehn and Yahr scale, Parkinson's disease has the following five stages:

Stage I: Symptoms are only on one side of the body
Stage II: Symptoms are on both sides of the body
Stage III: Balance is impaired
Stage IV: Assistance is required to walk and other symptoms are severe
Stage V: Wheelchair bound

There are several secondary symptoms that are caused by one or more of these four major symptoms. Many people have difficulty walking, resulting from a combination of postural instability and bradykinesia. The balance problems may cause them to stagger and add to a lurching gait. They may experience difficulty in turning or stopping as they walk, or they may inexplicably come to an abrupt stop. Loss of automatic movements may lead to a freezing of the facial muscles resulting in a "mask like" expression. They may also develop a fixed staring expression, and unblinking eyes. They may develop drooling, dizziness when moving from a seated to a standing position, difficult or frequent urination, difficulty speaking or swallowing, restlessness, eyelid closure, skin problems, excessive sweating, and sexual problems.

Mental Disorders

Depression: Due to the toll of living with their illness, and also due to the deficiencies of brain chemicals that are a part of the disease, many Parkinson's patients experience depression. Depression is marked by deep hopelessness and pessimism, and occurs in at least 40 percent of Parkinson's patients. A majority of patients experience anxiety that in turn may produce panic attacks. Panic attacks are overpowering fears, accompanied by breathlessness, sweating, chest pain, choking, and dizziness. Depression or anxiety that appears before motor symptoms develop are most likely caused by the disease itself, while depression or anxiety that occurs after the disease is diagnosed are usually due to the natural reaction to having a chronic and debilitating illness.

(It should be noted here that many Parkinson's patients and their families have found much relief in dealing with this disease by joining support groups. By checking with your healthcare provider, or by contacting the Parkinson's Foundation, you should be able to find one in your area.)

Dementia: At least thirty percent of Parkinson's patients develop dementia. Dementia is deterioration in intellect marked by memory losses, short attention span, impaired judgment, as well as personality changes. Twenty percent of People with Parkinson's experience cognitive impairment in which the information processes become slow. Planning or organizing skills, a decline in initiative and creativity may be compromised and completing simple tasks, such as balancing checkbook, becomes difficult. Dementia may be preceded by cognitive impairment.

Sleep problems: Sleep problems are also a symptom of Parkinson's. The sleep disturbance may be caused by depression or anxiety, or the drugs that are used to treat the Parkinson's could cause it. These patients may wake up frequently during the night, and may also act out their dreams (REM sleep behavior disorder). The disease may also cause this sleep disorder, as the sleep centers are located near the substantia nigra and may be altered by the disease.

Causes

While scientists do not understand the mechanisms underlying nigral cell deterioration in Parkinson's disease, most researchers believe that it results from a combination of factors that involve genetics, environmental agents, and abnormalities in cellular processes. Although Parkinson's has been thought to be mostly a genetic disease, a report published in the January 27,1999 issue of the Journal of the American Medical Association (JAMA), stated that it is instead more likely to be caused by environmental factors. The genetic factor has been debated for more than a century. Researchers have noted, however, that the disease is more common in the developed Western nations, fueling speculation that a byproduct of industrialization is to blame. A new study, the largest ever undertaken to examine the role of genetic or environmental causes of Parkinson's disease, was conducted by researchers at the Parkinson's Institute in Sunnyvale, California. The six-year study drew on the health records of nearly 20,000 white male twins. The records were contained in a registry of twins who fought in World War II (1939-1945). It was found that among men who developed the disease after the age of 50, the chance that their twin brother would also have the disease was equal to that of an unrelated stranger. About ninety percent of all cases of Parkinson's were diagnosed in men aged 50 or older. In the rare instances where Parkinson's developed before the age of 50, the researchers determined that genetic factors were important. Having eliminated genetic factors as a primary cause of the most common form of Parkinson's, the researchers concluded that an environmental agent most likely triggers the disease. These agents are unknown, but scientists have speculated that they could include exposure to pesticides and other chemicals, or something in the diet. In an editorial accompanying the new study, neurologist Jeffrey Cummings at the University of California (UCLA), wrote that the study findings should help refocus research on Parkinson's.

(It should be noted here, however, that scientists have yet to identify a particular drug or toxin that causes Parkinson's disease.)

Diagnosis

It is difficult to diagnose Parkinson's in the early stages, as no definitive tests exist for the disease. Many of the symptoms may be dismissed as the effects of aging, particularly in older adults. Healthcare Providers sometimes miss Parkinson's disease in the young, precisely because they believe it mainly affects older patients. A diagnosis is based on a patient's medical history, observations of the symptoms, and a neurological examination. The neurological examination includes an evaluation of the patient's walking, coordination, and some simple dexterity tests. Subtle signs such as reduced facial expressions, or lack of gestures or a subtle tremor are also noted. Healthcare providers may use brain-imaging techniques to help in their diagnosis. Magnetic resonance imaging (MRI), which uses electromagnetic radiation to view soft tissues of the body, can help the healthcare provider exclude other medical conditions that produce symptoms similar to Parkinson's disease.

Treatment

A person who suspects he/she might have Parkinson's should always contact their healthcare provider for a diagnosis and for treatment possibilities.

Depending on the symptoms, one healthcare provider may first try lifestyle changes such as diet, exercise, and physical therapy, while another may begin drug treatment at the first signs of the disease. Although the symptoms may be controlled by use of various drugs, and in some cases by surgery, there is no treatment that prevents the progressive brain changes in patients who have the disease. Physical therapy can be helpful both in the early and later stages. It can help improve not only mobility, range of motion and muscle tone, it can also help improve gait and balance. Working with a speech pathologist can help improve problems with speaking and swallowing. Drugs are used primarily for managing problems with walking, movement, and tremors, by increasing the brain's supply of dopamine. Dopamine itself cannot pass from the bloodstream to the brain, therefore, the drugs used to treat Parkinson's disease, known as antiparkinson drugs, use other methods to temporarily restore dopamine in the brain or closely mimic dopamine's actions.

Drugs Used Include

Levodopa (laradopa): an oral drug introduced in 1967 that treats bradykinesia, rigidity, tremor, and difficulty walking. Levodopa enters the brain where it transforms into dopamine. The body breaks down about 95 percent of the drug into dopamine before it reaches the brain if the drug is taken by itself. Therefore, it is usually combined with a drug such as carbidopa, which enables more levodopa to enter the brain before it converts into dopamine. Carbidopa/levodopa (Atamet, Sinemet) lessens rigidity and bradykinesia but is less effective in treating temor or balance problems. A similar drug (Madopar) combines carbidopa and benserazide and is available in Canada. As the disease progresses, the drug works less evenly. As a result some people may experience involuntary movements (dyskinesias), especially when the medication is having its peak effects. This causes what is known as the "off-on" phenomenon. Therefore, it is very important to work closely with your healthcare provider who can monitor the progress, and the treatment. Drugs that sustain levodopa's effectiveness, such as a controlled-release form of carbidopa/levodopa (Sinemet CR) are often used. Side effects include hallucinations, a drop in blood pressure (especially when standing), and nausea.

Dopamine Agonists: these are drugs that unlike levodopa are not changed into dopamine. Instead, they mimic the effects of dopamine in the brain and cause neurons to react as though sufficient amounts of dopamine were present. They are primarily used as adjuncts to levodopa therapy, but are also used in early therapy, and in younger adults. The side effects are similar to those of levodopa. This class of drugs includes bromocriptine (Parlodel) and pergolide (Permax) and the new drugs, pramipexole (Mirapex) and ropinirole (Requip). Only by working closely with the healthcare provider, however, can a person with Parkinson's receive the correct care for him/her.

Selegiline (Carbex, Eldepryl, Atapryl): this drug is used as an adjunct to levodopa therapy and helps prevent the breakdown of both naturally occurring dopamine and dopamine formed from levodopa. This occurs by inhibiting the activity of the enzyme monoamine oxidase B (MAO-B); the enzyme that metabolizes dopamine in the brain. Toxic reactions have occurred in some patients who took selegiline with the narcotic drug, meperidine (Demerol).

COMT inhibitors: are a newer class of drugs that work to prolong the effect of levodopa therapy by blocking an enzyme that breaks down dopamine in the liver and other organs. Tolcapone (Tasmar) is a potent COMT inhibitor that easily crosses the blood-brain barrier and doubles the time that levodopa is effective in the brain, and reduces the on-off effect. However, it has been linked to liver damage and liver failure and is normally used only in people who are not responding to other therapies. Entacapone (Comtan) is a milder COMT inhibitor that may help manage fluctuations in the response to levadopa.

Anticholinergics: these were the main drugs used before the introduction of levodopa. They are mildly beneficial in the earlier stages of Parkinson's and may lesson tremor and drooling, but are not effective in treating bradykinesia or posture instability. Anticholinergics block the action of acetycholine, which is responsible for problems with motor skills.

Amantadine (Symmetrel): this drug was originally developed as an antiviral drug. It is usually prescribed for people in the latter stages of Parkinson's disease, especially if they have problems with involuntary movements induced by levodopa (dyskinesias). Side effects include swollen ankles and a purple mottling of the skin.

(If you are taking medications for Parkinson's disease, it is extremely important not to stop taking them on your own. Always talk to your healthcare provider.)

Surgical Treatments

Surgical procedures were commonly used in the 1950's and 1960's to treat tremor and rigidity in Parkinson's patients. The success rate varied and life-threatening complications often occurred. Surgical treatment fell out of favor with the introduction of levodopa and other drug therapies. However, the surgical approaches are being re-evaluated to be used for times when symptoms cannot be controlled with medications. These surgical procedures include:

Thalamotomy: this procedure, used to reduce tremors in people with Parkinson's disease involves the destruction of small amounts of tissue in the thalamus - a major brain center for relaying messages and transmitting sensations. The surgery can cause extreme weakness and slurred speech if it is performed on both sides of the brain, and the benefits are usually confined to one side of the body.

Pallidotomy: in this procedure, an electric current is used to destroy a small amount of tissue in the globus pallidus, a part of the brain responsible for many symptoms of Parkinson's disease. It may improve tremors, rigidity and slowed movement by interrupting the neural pathway between the globus pallidus and the thalamus. It has proven helpful for some patients, but it is not a cure, and the effects do not always last. The surgery includes certain risks such as slurred speech, disabling weakness and vision problems, especially when performed on both sides of the body.

Deep brain stimulation: this is a device that helps control the disabling shaking and trembling caused by Parkinson's disease. A probe is inserted into the thalamus or globus pallidum and connects to a battery-powered generator outside of the body. When tremor or other uncontrolled movement starts, the patient turns the generator on and an electric signal sent to the brain halts the movement. In 1997, the Food and Drug Administration approved a new device that is implanted in the chest and transmits electrical pulses via a wire to an implant in the thalamus. Potential risks exist with the DBS, including infection caused by the wire connecting the electrode to the stimulator and the need to perform minor surgery to change the unit's battery.

Experimental Treatments Include

Fetal cell transplantation: a procedure in which fetal cells are implanted into the brains of people with Parkinson's. This procedure is used to replace the dopamine-producing cells in the substantia nigra. However, a study, published in the March 8, 2001 issue of the New England Journal of Medicine, suggested that fetal cells implants only benefit people under the age of 60, and about 15 percent of the study participants later developed severe involuntary movements (dyskinesias) as a result of too much dopamine.

Embryonic stem cells: these are the parent cells of all tissues in the body, and the hope is that they may one day be used to reproduce specific types of cells - such as dopamine-producing neurons - that can be used to treat disease. Stem cells can also be obtained from the discarded umbilical cord from healthy babies, and the bone marrow of adults. Using stem cells from these sources make this treatment more acceptable and may go far in alleviating the controversy surrounding the use of embryonic stem cells.

(Both of these treatments are still in the research phase, and are not available to the public. At this time they are still experimental treatments.)

Self-Help

In addition to the various treatment procedures there are many things a person diagnosed with Parkinson's can do to help him/herself. While any and all treatments and therapies should be discussed with one's healthcare provider, the following may be of help:

Nutrition/Diet: Because it is believed that Parkinson's may be associated with free radicals (potentially damaging molecules produced in cells as part of cell activity or in response to injury), it is important to eat foods that contain antioxidants. Foods that contain antioxidants are fruits, vegetables and whole grains. A balanced diet that contains these can help protect against free radical damage. They are also high in fiber, which is important for the Parkinson's patients that suffer from constipation. Your healthcare provider may advise taking a fiber supplement, such as Metamucil or Citrucel, however, it should be introduced slowly and it is imperative to drink eight to ten glasses of water daily. Limiting caffeine and alcohol is also helpful. Reducing the consumption of fat, especially saturated fats can be helpful in maintaining an acceptable weight. Because Parkinson's disease slows gastric motility, swallowing is prolonged, and therefore food absorption is slower. Eating small amounts of food throughout the day is better for the Parkinson's patient than three large meals. If a Parkinson's patient is taking Simemet, it should be taken on an empty stomach. Even taking it fifteen minutes before eating is preferable. If nausea is present, it may be taken with a non-dairy fluid and a small cracker, bite of fruit, even a pretzel. Ginger has been found to be helpful in offsetting nausea. Taking Simemet on an empty stomach allows it to be absorbed more easily and quickly. Some healthcare providers may recommend vitamin or antioxidant supplements. Talk to your healthcare provider about the benefit of adding these to your diet. Parkinson's patients often have trouble swallowing, especially in the latter stages of the disease, therefore it is important to remember to take small bites of food, chewing them completely and swallowing before taking another bite. Chopping food in a food processor may also be helpful, as would using a plate warmer under the plate to insure the food doesn't get cold, thus allowing you to take your time in eating.

Exercise: Regular exercise is important for Parkinson's patients. It aids in mobility, balance, and range of motion. Your healthcare provider may recommend an exercise program for you, however, walking, swimming, and gardening have all proved beneficial. Studies have shown that activities such as walking, jogging, and even dancing may be more helpful than physical therapy. Making sure that your medicines are working well and you are feeling strong, as the energy level may go up and down, are important things to consider before beginning any exercise. In the case of fatigue, it may be helpful to do part of your exercise routine in the morning, and another part in the evening. Make sure and stretch before exercising as this helps to warm up the muscles and also helps to prevent stiffness. Stretching also improves balance and flexibility. Some healthcare providers are suggesting that their patients try Tai Chi, a Chinese form of exercise that uses slow, graceful movements to relax and strengthen the muscles and joints. It is also known to be beneficial in improving balance. It is imperative to always consult with your healthcare provider before starting any exercise program.

Walking: Walking is difficult for the Parkinson's patients, especially in the latter stages due to the shuffling and foot drag that is common to this disease. Making sure to use proper posture and wearing the right shoes, such as a pair of good walking shoes can help. One of the problems that Parkinson's patients face is what is known as "freezing". This usually happens when a person with Parkinson's stops or tries to pivot in order to turn and their feet become "frozen" in place. Rocking gently from side to side, or pretending to step over an object on the floor can aid in this. Avoiding prolonged standing, using a large rubber tipped cane, using a forward facing wide U-turn rather than the usual pivoting and keeping distractions to a minimum can help the patient avoid falls. Also, standing with feet eight to ten inches apart instead of close together may be of help. There are many products on the market that can help the people who have Parkinson's disease. These would include handrails (especially on staircases) and grab bars for around the tub and beside the toilet. Removing area rugs can also help. Music Therapy, a therapy that uses music and rhythm to help improve the patient's mobility and balance has been used with some success. You can check with your healthcare provider to find this therapy in your area.

Dressing: As dressing can become an ordeal for a person who has Parkinson's, it might be helpful not only to allow plenty of time for dressing, but also to choose clothes that slip on easily or that have Velcro fasteners rather than buttons or zippers.

Speaking: A person who has Parkinson's often speaks with a soft of hoarse voice. In order to communicate more easily, face the person you are talking to and speak deliberately and more loudly than you think necessary. Reading or singing out loud while focusing on breathing aids in strengthening the vocal cords and the throat muscles which in turn aid in swallowing. Consulting with a speech pathologist that is trained to treat Parkinson's patients can also be beneficial.

Parkinson's is a progressive disease, and while none of these tips can eliminate or cure any of the problems associated with Parkinson's, making certain lifestyle changes can help make living with the disease easier.

The information in this or any article should never be used to diagnose oneself. If Parkinson's or any disease is suspected, a healthcare provider should be contacted as soon as is possible, in order to detect early symptoms and begin treatment.

Additional Resources

American Healthcare Association (202) 842-4444
Americans with Disabilities Act Regional and Technical Assistance Centers (800) 949-4232
The National Council On the Aging, Inc. (202) 479-1200
National Council on Disability (202) 347-1234
The National Parkinson's Foundation encourages all patients to request a Parkinson's Medical Alert card if they don't already have one. This card alerts anyone rendering assistance that the individual has Parkinson's disease. It provides emergency contact numbers so that the family and/or healthcare provider may be contacted, as well as important medical information.
To request your card call: 1 (800) 327-4545.