Parkinson's disease

Definition

Parkinson's disease is a progressive disorder of the nervous system that affects movement. It develops gradually, often starting with a barely noticeable tremor in just one hand. But while tremor may be the most well-known sign of Parkinson's disease, the disorder also commonly causes a slowing or freezing of movement.

Friends and family may notice that your face shows little or no expression and your arms don't swing when you walk. Speech often becomes soft and mumbling. Parkinson's symptoms tend to worsen as the disease progresses.

While there is no cure for Parkinson's disease, many different types of medicines can treat its symptoms. In some cases, your doctor may suggest surgery.

Symptoms

The symptoms of Parkinson's disease can vary from person to person. Early signs may be subtle and can go unnoticed. Symptoms typically begin on one side of the body and usually remain worse on that side even after symptoms begin to affect both sides. Parkinson's signs and symptoms may include:

• Tremor. The characteristic shaking associated with Parkinson's disease often begins in a hand. A back-and-forth rubbing of your thumb and forefinger, known as pill-rolling, is common, and may occur when your hand is at rest. However, not everyone experiences tremors.
• Slowed motion (bradykinesia). Over time, Parkinson's disease may reduce your ability to initiate voluntary movement. This may make even the simplest tasks difficult and time-consuming. When you walk, your steps may become short and shuffling. Or your feet may freeze to the floor, making it hard to take the first step.
• Rigid muscles. Muscle stiffness can occur in any part of your body. Sometimes the stiffness can be so severe that it limits the range of your movements and causes pain. People may first notice this sign when you no longer swing your arms when you're walking.
• Impaired posture and balance. Your posture may become stooped as a result of Parkinson's disease. Balance problems also may occur, although this is usually in the later stages of the disease.
• Loss of automatic movements. Blinking, smiling and swinging your arms when you walk are all unconscious acts that are a normal part of being human. In Parkinson's disease, these acts tend to be diminished and even lost. Some people may develop a fixed staring expression and unblinking eyes. Others may no longer gesture or seem animated when they speak.
• Speech changes. Many people with Parkinson's disease have problems with speech. You may speak more softly, rapidly or in a monotone, sometimes slurring or repeating words, or hesitating before speaking.
• Dementia. In the later stages of Parkinson's disease, some people develop problems with memory and mental clarity. Alzheimer's drugs appear to alleviate some of these symptoms to a mild degree.

When to see a doctor
See your doctor if you have any of the symptoms associated with Parkinson's disease — not only to diagnose the illness but also to rule out other causes for your symptoms.

Causes

The exact cause of Parkinson's disease is unknown, but several factors appear to play a role, including:

• Your genes. Researchers have found specific genetic mutations that likely play a role in Parkinson's disease. In addition, scientists suspect that many more changes in genes — whether inherited or caused by an environmental exposure — may be responsible for Parkinson's disease.
• Environmental triggers. Exposure to toxins or certain viruses may trigger Parkinson's signs and symptoms.

In addition, numerous changes are found in the brains of people with Parkinson's disease. The role of these factors in the development of the disease, if any, isn't clear, however. These changes include:

• A lack of dopamine. Many symptoms of Parkinson's disease result from the lack of a chemical messenger, called dopamine, in the brain. This occurs when the specific brain cells that produce dopamine die or become impaired. Why and exactly how this happens isn't known.
• Low norepinephrine levels. People with Parkinson's disease also have damage to the nerve endings that make another important chemical messenger called norepinephrine. Norepinephrine plays a role in regulating the autonomic nervous system, which controls automatic functions, such as blood pressure regulation.
• The presence of Lewy bodies. Unusual protein clumps called Lewy bodies are found in the brains of many people with Parkinson's disease. How they got there and what type of damage, if any, Lewy bodies might cause is still unknown.

Risk factors

Risk factors for Parkinson's disease include:

• Age. Young adults rarely experience Parkinson's disease. It ordinarily begins in middle or late life, and the risk continues to increase with age.
• Heredity. Having a close relative with Parkinson's increases the chances that you'll also develop the disease, although your risk is still no more than about 4 to 6 percent.
• Sex. Men are more likely to develop Parkinson's disease than women are.
• Exposure to toxins. Ongoing exposure to herbicides and pesticides puts you at slightly increased risk of Parkinson's.

Complications

Parkinson's disease is often accompanied by these additional problems:

• Depression. Depression is common in people with Parkinson's disease. Receiving treatment for depression can make it easier to handle the other challenges of Parkinson's disease.
• Sleep problems. People with Parkinson's disease often have trouble falling asleep and may wake up frequently throughout the night. They may also experience sudden sleep onset, called sleep attacks, during the day.
• Difficulty chewing and swallowing. The muscles you use to swallow may be affected in the later stages of the disease, making eating more difficult.
• Urinary problems. Parkinson's disease may cause either urinary incontinence or urine retention. Certain medications used to treat Parkinson's also can make it difficult to urinate.
• Constipation. Many people with Parkinson's disease develop constipation because the digestive tract works more slowly. Constipation may also be a side effect of medications used to treat the disease.
• Sexual dysfunction. Some people with Parkinson's disease may notice a decrease in sexual desire. This may stem from a combination of psychological and physical factors, or it may be the result of physical factors alone.

Medications for Parkinson's disease also may cause a number of complications, including involuntary twitching or jerking movements of the arms or legs, hallucinations, sleepiness, and a drop in blood pressure when standing up.

Preparing for your appointment

You're likely to first see your family doctor or a general practitioner. However, you may then be referred to a doctor who specializes in disorders of the nervous system (neurologist).

Because appointments can be brief, and there's often a lot of ground to cover, it's a good idea to arrive well prepared. Here's some information to help you get ready for your appointment, and what to expect from your doctor.

What you can do

• Write down any symptoms you're experiencing, including any that may seem unrelated to the reason for which you scheduled the appointment.
• Write down key personal information, including any major stresses or recent life changes.
• Make a list of all medications, vitamins and supplements that you're taking.
• Ask a family member or friend to come with you, if possible. Sometimes it can be difficult to remember all of the information provided to you during an appointment. Someone who accompanies you may remember something that you missed or forgot.
• Write down questions to ask your doctor.

Preparing a list of questions can help you make the most of your time together. For Parkinson's, some basic questions to ask your doctor include:

• What's the most likely cause of my symptoms?
• Are there other possible causes for my symptoms?
• What kinds of tests do I need? Do these tests require any special preparation?
• How does Parkinson's disease usually progress?
• Will I eventually need long-term care?
• What treatments are available, and which do you recommend for me?
• What types of side effects can I expect from treatment?
• If the treatment doesn't work or stops working, do I have additional options?
• I have other health conditions. How can I best manage these conditions together?
• Are there any restrictions on my activity?
• Is there a generic alternative to the medicine you're prescribing me?
• Are there any brochures or other printed material that I can take home with me? What Web sites do you recommend visiting?

In addition to the questions that you've prepared to ask your doctor, don't hesitate to ask questions during your appointment at any time that you don't understand something.

What to expect from your doctor
Your doctor is likely to ask you a number of questions. Being ready to answer them may reserve time to go over any points you want to spend more time on. Your doctor may ask:

• When did you first begin experiencing symptoms?
• Have your symptoms been continuous or occasional?
• Does anything seem to improve your symptoms?

Tests and diagnosis

No definitive tests exist for Parkinson's disease, so it can be difficult to diagnose, especially in the early stages. And parkinsonism — the symptoms of Parkinson's disease — can be caused by many other types of problems. For example, other neurological disorders, toxins, head trauma and even some medications — such as chlorpromazine (Thorazine), prochlorperazine (Compazine) or metoclopramide (Reglan) — can cause parkinsonism.

A diagnosis of Parkinson's disease is based on your medical history and a neurological examination:

• Medical history. As part of your medical history, your doctor will want to know about any medications you take and whether you have a family history of Parkinson's.
• Neurological exam. This examination includes an evaluation of your walking and coordination, as well as some simple hand tasks.

A diagnosis of Parkinson's is most likely if you have:

• At least two of the three cardinal Parkinson's signs and symptoms — tremor, slowing of motion and muscle rigidity
• Onset of symptoms on only one side of the body
• Tremor more pronounced at rest, for example, when your hands are resting in your lap
• Significant improvement with levodopa, a Parkinson's drug

Treatments and drugs

There's no cure for Parkinson's disease, but medications can help control some of the symptoms of Parkinson's disease, and in some case, surgery may be helpful. Your doctor may recommend lifestyle changes, such as physical therapy, a healthy diet and exercise, in addition to medications.

Medications
Medications can help manage problems with walking, movement and tremor by increasing the brain's supply of dopamine. However, taking dopamine itself is not helpful, because it's unable to enter your brain.

Your initial response to Parkinson's treatment can be dramatic. Over time, however, the benefits of drugs frequently diminish or become less consistent, although symptoms can usually still be fairly well controlled.

Examples of medication your doctor may prescribe include:

• Levodopa. The most effective Parkinson's drug is levodopa, which is always taken as a combination drug with another medication. Levodopa is a natural substance in the body. When taken by mouth in pill form, it passes into the brain and is converted to dopamine. Levodopa is combined with carbidopa to create the combination drug, Sinemet. The carbidopa protects levodopa from premature conversion to dopamine outside the brain; in doing that, it also prevents nausea. In Europe, levodopa is combined with a similar substance, benserazide, and is marketed as Madopar.

  As the disease progresses, the benefit from levodopa may become less stable, with a tendency to wax and wane ("wearing off"). This then requires medication adjustments. Levodopa side effects include involuntary movements called dyskinesia. These resolve with dose reduction, but sometimes at the expense of reduced parkinsonism control. Like other Parkinson's drugs, it may also lower your blood pressure when standing.

• Dopamine agonists. Unlike levodopa, these drugs aren't changed into dopamine. Instead, they mimic the effects of dopamine in the brain and cause neurons to react as though dopamine is present. They are not nearly as effective in treating the symptoms of Parkinson's disease. However, they last longer and are often used to smooth the sometimes off-and-on effect of levodopa.

  This class includes pill forms of dopamine agonists, such as pramipexole (Mirapex) and ropinirole (Requip). A short-acting injectable dopamine agonist, apomorphine (Apokyn), is used for quick relief.

  The side effects of dopamine agonists include hallucinations, sleepiness, water retention and low blood pressure when standing. These medications may also increase your risk of compulsive behaviors such as hypersexuality, compulsive gambling and compulsive overeating. If you are taking these medications and start behaving in a way that's out of character for you, talk to your doctor.

• MAO B inhibitors. These types of drugs, including selegiline (Eldepryl) and rasagiline (Azilect), help prevent the breakdown of both naturally occurring dopamine and dopamine formed from levodopa. They do this by inhibiting the activity of the enzyme monoamine oxidase B (MAO B) — an enzyme that metabolizes dopamine in the brain. Side effects are rare but may include confusion, headache, hallucinations and dizziness. These medications can't be used in combination with other antidepressants, the antibiotic ciprofloxacin (Cipro), the herb St. John's wort or certain narcotics. Check with your doctor before taking any additional medications with an MAO inhibitor.
• Catechol O-methyltransferase (COMT) inhibitors. These drugs prolong the effect of carbidopa-levodopa therapy by blocking an enzyme that breaks down levodopa. Tolcapone (Tasmar) has been linked to liver damage and liver failure, so it's normally used only in people who aren't responding to other therapies. Entacapone (Comtan) doesn't cause liver problems and is now combined with carbidopa and levodopa in a medication called Stalevo. However, it may worsen other levodopa side effects, such as involuntary movements (dyskinesias), nausea, confusion or hallucinations. It may cause urine discoloration.
• Anticholinergics. These drugs have been used for many years to help control the tremor associated with Parkinson's disease. A number of anticholinergic drugs, such as benztropine (Cogentin) and trihexyphenidyl, are available. However, their modest benefits are often offset by side effects such as impaired memory, confusion, constipation, dry mouth and eyes, and impaired urination.
• Glutamate (NMDA) blocking drugs. Doctors may prescribe amantadine (Symmetrel) alone to provide short-term relief of mild, early-stage Parkinson's disease. It also may be added to carbidopa-levodopa therapy for people in the later stages of Parkinson's disease, especially if they have problems with involuntary movements (dyskinesia) induced by carbidopa-levodopa. Side effects include a purple mottling of the skin and, sometimes, hallucinations.

Physical therapy
Exercise is important for general health, but especially for maintaining function in Parkinson's disease. Physical therapy may be advisable and can help improve your mobility, range of motion and muscle tone. Although specific exercises can't stop the progress of the disease, maintaining muscle strength and agility can help counter some of the progressive tendencies of the disease and also allow you to feel more confident and capable. A physical therapist can also work with you to improve your gait and balance. A speech therapist or speech pathologist can improve problems with speaking and swallowing.

Surgery
Deep brain stimulation is a surgical procedure used to treat Parkinson's disease. It involves implanting an electrode deep within the parts of your brain that control movement. The amount of stimulation delivered by the electrode is controlled by a pacemaker-like device placed under the skin in your upper chest. A wire that travels under your skin connects the device, called a pulse generator, to the electrodes.

Deep brain stimulation is most often used for people with advanced Parkinson's disease who have unstable medication (levodopa) responses. It can stabilize medication fluctuations and reduce or eliminate involuntary movements (dyskinesia). Tremor is especially responsive to this therapy.

Serious risks of this procedure are uncommon, but include brain hemorrhage or stroke. Infection is also a risk, and sometimes requires parts of the device to be replaced. Deep brain stimulation isn't beneficial for people who don't respond to carbidopa-levodopa.

Deep brain stimulation

Deep brain stimulation

Deep brain stimulation involves implanting an electrode deep within your brain. The amount of stimulation delivered by the electrode is controlled by a pacemaker-like device placed under the ...

Lifestyle and home remedies

If you've received a diagnosis of Parkinson's disease, you'll need to work closely with your doctor to find a treatment plan that offers you the greatest relief from symptoms with the fewest side effects. Certain lifestyle changes also may help make living with Parkinson's disease easier.

Healthy eating
Eat a nutritionally balanced diet that contains plenty of fruits, vegetables and whole grains. These foods are high in fiber, which is important for helping prevent the constipation that is common in Parkinson's disease. A balanced diet also provides nutrients, such as omega-3 fatty acids, that may be beneficial for people with Parkinson's disease.

If you take a fiber supplement, such as psyllium powder, Metamucil or Citrucel, be sure to introduce it gradually and drink plenty of fluids daily. Otherwise, your constipation may become worse. If you find that fiber helps your symptoms, use it on a regular basis for the best results.

Walking with care
Parkinson's disease can disturb your sense of balance, making it difficult to walk with a normal gait. These suggestions may help:

• Try not to move too quickly.
• Aim for your heel to strike the floor first when you're walking.
• If you notice yourself shuffling, stop and check your posture. It's best to stand up straight.

Avoiding falls
In the later stages of the disease, you may fall more easily. In fact, you may be thrown off balance by just a small push or bump. The following suggestions may help:

• Don't pivot your body over your feet while turning. Instead, make a U-turn.
• Don't lean or reach. Keep your center of gravity over your feet.
• Don't carry things while walking.
• Avoid walking backward.

Dressing
Dressing can be the most frustrating of all activities for someone with Parkinson's disease. The loss of fine motor control makes it hard to button and zip clothes, and even to step into a pair of pants. An occupational therapist can point out techniques that make daily activities easier. These suggestions also may help:

• Allow plenty of time so that you don't feel rushed.
• Lay clothes nearby.
• Choose clothes that you can slip on easily, such as sweat pants, simple dresses or pants with elastic waistbands.
• Use fabric fasteners, such as Velcro, instead of buttons.

Alternative medicine

Forms of alternative medicine that may help people with Parkinson's include:

• Coenzyme Q10. People with Parkinson's disease tend to have low levels of coenzyme Q10, and some research has suggested it may be beneficial. However, subsequent research hasn't confirmed this benefit. You can buy coenzyme Q10 without a prescription in drugstores and natural food stores. Talk with your doctor before taking this supplement to ensure that it won't interfere with any medication you may be taking.
• Massage. Massage therapy can reduce muscle tension and promote relaxation, which may be especially helpful to people experiencing muscle rigidity associated with Parkinson's disease. These services, however, are rarely covered by health insurance.
• Tai chi. An ancient form of Chinese exercise, tai chi employs slow, flowing motions that help improve flexibility and balance. Several forms of tai chi are tailored for people of any age or physical condition.
• Yoga. Yoga is another type of exercise that increases flexibility and balance. Most poses can be modified, depending on your physical abilities.

Coping and support

Living with any chronic illness can be difficult, and it's normal to feel angry, depressed or discouraged at times. Parkinson's disease presents special problems because it can cause chemical changes in your brain that make you feel anxious or depressed. And Parkinson's disease can be profoundly frustrating, as walking, talking and even eating become more difficult and time-consuming.

Although friends and family can be your best allies, the understanding of people who know what you're going through can be especially helpful. Support groups aren't for everyone, but for many people, they can be a good resource for practical information about Parkinson's disease, as well as a place to find understanding from people that are going through the same things you are.

To learn about support groups in your community, talk to your doctor, a Parkinson's disease social worker or a local public health nurse. Or contact the National Parkinson Foundation or the American Parkinson Disease Association.

Prevention

Since the cause of Parkinson's is unknown, definitive ways to prevent the disease also remain a mystery. However, some research has shown that caffeine — which is found in coffee, tea and cola — may reduce the risk of developing Parkinson's disease.