Parkinson’s disease is common. It affects about 500,000 to one million Americans, or about 1% of people over the age of 60. After Alzheimer’s disease, it is the second most common progressive, neurological disorder in the US. In the state of Rhode Island alone, with a population of only one million people, there are an estimated 1000 to 2,000 people with PD. Although there is a large body of research on Parkinson’s disease, we still don’t know what causes it, and we even have some trouble diagnosing it at times.
Parkinson’s disease is a disorder that affects small regions in the brain that control movement, posture, and balance. It is a complex disease that has many different symptoms, so that not everyone with the condition suffers from the same problems.
The more that Parkinson’s disease is studied, the more intricate we find the condition to be. Only over the past 15 years or so have doctors started to investigate the effect of Parkinson’s on behavior. Treatment of Parkinson’s has focused until recently only on the movements, but we now see the disorder in a more realistic, holistic way. Quality of life has become a more central focus as we deal with a disease we cannot yet cure.
About Parkinson’s Disease
Parkinson’s disease is named after British doctor James Parkinson who wrote the first book about the disease, in 1817. Parkinson called it, “The Shaking Palsy,” or “paralysis agitans.” In his day, the term “agitans” referred to tremors. “Palsy” meant weakness and “paralysis” meant paralyzed, so the condition was considered a disorder of weakness and tremors, which is not entirely true, as we shall see. Parkinson was famous in his day because of his political activities, his scientific publications on geology and his invention of the truss, in the days before surgery for hernias was available.
It took 100 years before the major brain changes were first noted in the brains of people with Parkinson’s disease, and another 50 years after that before most experts agreed that these changes were, in fact, the disease process itself. In the early 1960s, we began to understand more about the importance of the brain chemical dopamine (di-ortho-phenyl-alanine). Shortly thereafter L-Dopa was introduced, the first substantive treatment for Parkinson’s Disease. L-Dopa wasn’t very popular at first because it caused nausea and vomiting. Carbidopa was developed soon after, to prevent the vomiting, leading to the combined medication, Sinemet (sine=without, emesis=vomiting). This drug remains the single best medication we have for treating the symptoms of Parkinson’s disease.
Parkinson’s Disease: Diagnosis
Although Parkinson’s disease is a specific, well-defined disease that can be reliably diagnosed at autopsy; it is defined in life solely by clinical criteria. This means the diagnosis rests entirely on the information (history) the patient provides and the findings of the physical examination. A doctor may recommend tests to rule out other disorders that might look like Parkinson’s disease, but there is no test to diagnose Parkinson’s. This means we can never be 100% certain that we’ve diagnosed someone correctly.
That being said, we look for certain core features during examination, as well as a supportive history. For example, Parkinson’s disease is slow in onset, so if a patient said that she woke up one morning with tremors and a shuffling walk, but had been playing competitive tennis the evening before, we’d think that she more likely had a brain infection or had taken a medication with bad side effects.
Parkinson’s disease generally presents slowly, with progressive changes developing over months. For example, a patient may experience one or more of the following changes:
- Intermittent tremors (usually in the hands or jaw)
- Overall sluggishness or a sense of slowing down in general
- Difficulty getting out of a car seat or a low, soft sofa
- Softening of the voice
- Smallness and slowing of handwriting
- Change in posture and facial expression
Very often something is only noticed on a particular day, but friends and family will generally report that although they didn’t notice particular changes, now that they know what to look for, the changes began months or even years before.
Parkinson’s Disease: Tremor
With Parkinson’s disease, tremor occurs primarily at rest. This means that the tremor goes away when the limb is moving but returns when the limb relaxes completely. The tremor is usually asymmetric, affecting one side more than the other, or affecting only one side. The fingers and hands are the body parts most commonly affected, followed by the jaw. The legs and feet may also be affected, but less so. In fact, virtually any body part can be affected by tremor, including the tongue, eyebrow, and lips.
The tremor sometimes disappears during sleep, but increases during periods of stress and excitement, after exercise, and in the cold. It may be present all the time, or only very occasionally. It may sometimes affect one hand and sometimes both. During times of relaxation it may completely disappear. It always disappears when the limb is moving.
Sometimes patients will describe having a tremor at home, but not have it in the office. This is uncommon, but does occur. In such circumstances the doctor cannot rely on the patient’s report because the nature of the tremor is important, and not all tremors are due to Parkinson’s disease.
Parkinson’s Disease: Rigidity
Patients with Parkinson’s disease have some degree of stiffness or rigidity in their joints. It most commonly appears in the wrists and neck, but may be present everywhere. The patient may feel stiff, but not always. During examination, the doctor will move the patient’s limbs to test for stiffness in the wrists, elbows, fingers, neck, and legs. A normal person’s joints move like well-oiled machine parts, but someone with Parkinson’s disease will have a resistance to the movement, even though the person is relaxed. This resistance often, although not always, has a ratchet-like quality to it, called “cogwheel rigidity” because the movement feels like a cogged wheel moving.
Parkinson’s Disease: Absence of Movement or “Akinesia”
Akinesia means “absence of movement” and refers to the absence or reduction of normal spontaneous activity. Parkinson’s disease patients are like statues—they tend to not move. They blink less than others, swallow less, and have fewer movements like touching their face, scratching their nose, and shifting positions in their chair. This is one of the causes for the “staring” expression and the “masked facial expression” of Parkinson’s disease patients. It is also the cause for drooling (inadequate swallowing).
Parkinson’s Disease: Slowness or “Bradykinesia”
Bradykinesia means “slowness of movement” and is one of the main causes of disability in Parkinson’s disease. Parkinson’s patients move more slowly than others. They have reduced dexterity, particularly in their fingers, so it takes a long time to button, zipper, manipulate small objects, put a screw into the wall, get money out of a wallet, etc. As one patient described it, “My left hand is fine, but I have to tell my right hand what to do. That slows me down a lot.” Patients sometimes have to consciously will an action that used to happen automatically, without thinking. If you had to “tell” your hand what to do to comb your hair, and guide each of its movements, it would take a lot longer than it should. This is what happens in Parkinson’s disease. This also keeps PD patients from being able to do two things at the same time, another source of slowness.
Parkinson’s Disease: Gait and Posture
The word “gait” refers to how you walk. Parkinson’s disease patients tend to become stooped. When they walk they don’t swing their arms, or they swing them less than normal. They tend to walk with their foot hitting the ground flatly, rather than having their heel hit the ground first. The distance between the feet, as they take steps, tends to decrease, and the speed of walking diminishes as well. The heel may scuff the floor. When they turn, they tend to take a few steps rather than pivoting (rotating on one foot).
Balance is impaired so that when knocked off balance, the Parkinson’s disease patient may take several steps to keep from falling, or simply lose balance and fall, if not caught. The standard exam for Parkinson’s disease has the patient pulled from behind for a balance check. The doctor is prepared to catch the patient.
Other features that are common in Parkinson’s disease but are not considered “core” or “cardinal” features are: changes in voice, penmanship, sleep. The voice may become soft. Many patients develop a stutter, or develop an increased rate of speaking, despite having difficulty being understood. Penmanship, in addition to becoming slow and sometimes shaky, also becomes small. There are many sleep problems that develop in Parkinson’s disease, but the one that is most indicative of a diagnosis of Parkinson’s disease is “REM sleep disorder,” a condition in which patients may act out their dreams, kicking, punching, and yelling while asleep.
In thinking about the above, it is important to keep in mind one very important underlying principle of brain function. Each part of the brain has a particular function, so that if you damage a particular location in the brain, it will cause a very specific change in the person’s function. It doesn’t matter how that part of the brain is damaged, whether from a stroke, a tumor, a bullet wound or an infection. This is one of the reasons we can’t always be sure that the diagnosis is Parkinson’s disease. We can state that the particular part of the brain that is damaged in Parkinson’s disease is affected, but we may be wrong about the process that is the cause. There are several different disorders that look very much like Parkinson’s disease. Early on it may be impossible to tell if a patient has Parkinson’s disease or some closely related disorder. This is especially true in elderly patients, since many of the normal changes that occur with age may look like Parkinson’s disease.
Parkinson’s Disease: Treatment
Although there is no cure for Parkinson’s disease, there are medications that can provide relief from many of the symptoms.Most medications used to treat the disease either mimic the effect of dopamine, increase dopamine levels, or extend the action of dopamine in the brain. The challenge is to find a medication that relieves symptoms with limited side effects.
Medications used to treat the symptoms of Parkinson’s disease cannot stop the disease from progressing over time. But they may help relieve the symptoms and help a person with Parkinson’s disease to carry on daily activities.
As the disease progresses, drug dosages may have to be modified and medication regimens changed. Sometimes a combination of drugs may be given.
Patients may also benefit from physical therapy, nutritional supplements and massage therapy. Some patients may also be candidates for deep brain stimulation, a tremor control therapy for patients who no longer respond effectively to medications.
Parkinson’s Disease: Resources
APDA Rhode Island Chapter
Post Office Box 41659
Providence, RI 02940-1659
Tel: 401-823-5700 or 800-498-2732
The American Parkinson’s Disease Association
135 Parkinson Ave.
Staten Island, NY 10305
Tel: (718) 981-8001 or (800) 223-2732
The Michael J. Fox Foundation for Parkinson’s Research
Grand Central Station
P.O. Box 4777
New York, NY 10163
National Alliance for Caregiving
4720 Montgomery Lane, 5th Floor
Bethesda, MD 20814
National Institute of Neurological Disorders and Stroke
NIH Neurological Institute
P.O. Box 5801
Bethesda, MD 20824
National Parkinson Foundation, Inc.
1501 N.W. Ninth Avenue
Miami, FL 33136
Tel: (305) 547-6666 or 800 327-4545
Parkinson’s Action Network
1025 Vermont Ave NW Suite 1120
Washington, DC 20005
Tel: (202) 638-4101
Toll Free: 1-800-850-4726
Fax: (202) 638-7257