When Michael J. Fox disclosed that he suffers from Parkinson’s disease, he was deluged with offers of help and encouragement. Though Fox’s case has heightened public awareness of the disease, he is only the latest in a long list of prominent people to experience the ravages of Parkinson’s—among them, Pope John Paul II, Janet Reno, Mao Zedong and Congressman Mo Udall, who died Dec. 12 of complications of the disease.
Named for James Parkinson, who in 1817 first described its symptoms in his treatise The Shaking Palsy, Parkinson’s affects nearly 1 million Americans. While advances in research and treatment have greatly improved the prognosis for these patients (only 10 percent of whom, like Fox, develop symptoms before the age of 40), Parkinson’s is still “an insidious disease that threatens one’s quality of life as it progresses,” says neurologist Dr. Stanley Fahn, 65, a leading Parkinson’s researcher. Fahn, who in the early 1980s diagnosed Muhammad Ali with the disease, now heads the Parkinson’s research unit at New York City’s Presbyterian Hospital. He spoke with correspondent Bob Meadows about the lingering mysteries of Parkinson’s.
What is Parkinson’s disease?
It’s a degenerative neurological disorder whose symptoms include tremors, rigidity and unusually slow movement. As the disease progresses, patients become bent over and have a tendency to fall or lose their balance. In the more progressed stage, they experience the freezing phenomenon: For a few seconds, they can’t move at all.
Can people die from Parkinson’s?
Before the current best treatments, the mortality rate was three times higher than for the average person. Now it’s 1.5 times as high. The saying is that you don’t die from Parkinson’s; you die with it. As the disease advances, the immune system weakens, patients can develop ulcers or pneumonia, and swallowing can be impaired. But most die from unrelated, natural causes. I’ve had patients for more than 20 years who were fine as long as they had their medicine. Still, the disease itself never disappears.
What causes Parkinson’s?
A lack of a neurotransmitter called dopamine, which is ordinarily found in a section of the brain called the basal ganglia, where tremors, tics and other abnormal movements are rooted. When dopamine cells die there, and in another part of the brain called the striatum, people begin to lose motor control.
Why do the cells die in some people?
For patients who get Parkinson’s at a young age, the cause is probably hereditary. Three-quarters of people who get it are older than 50, and in those cases genetics does not seem to play a major role. We don’t know what causes the great majority of Parkinson’s cases.
What are the first signs of the disease?
Sometimes symptoms are so subtle that they might not be recognized initially. A person might notice that a spouse isn’t swinging an arm when they’re walking, or might be dragging a leg. Little things begin happening: Handwriting gets smaller, or it takes longer to put on lipstick, turn over in bed or get out of a chair.
So how is the disease diagnosed?
Usually, when a patient develops two out of three symptoms—rigidity, tremors or severe slowness—you can be pretty confident that someone has Parkinson’s. The problem is that by the time symptoms begin to show, about 70 percent of the dopamine in the brain has already died. Once gone, it cannot be regenerated. Fortunately, a new drug [Altropane] can help in confirming diagnoses and in treating the disease. It binds to dopamine and can then be traced. We’re also hoping that a similar drug, Dopascan, and a procedure called a Fluoradopa PET scan will be tools for measuring how much dopamine is being lost when we use one treatment versus another.
What are the treatments?
As late as the 1950s there was no effective treatment. Then, in 1960, Levadopa, a natural chemical that turns into dopamine when it is introduced into the body, began to be administered by injection, but it caused excessive vomiting. Later, a researcher named George Cotzias found that by starting with small doses, people could get used to it. That was a revolutionary step.
The major drug we use today is Sinemet, which combines Levadopa with another chemical. Sine is Latin for “without,” and mesis means “vomiting”: “without vomiting.” It does nothing for slowed movement.
Does the drug have a downside?
At least 75 percent of people treated with it for at least five years develop motor complications. The Levadopa in Sinemet can give patients involuntary movements, such as hand and leg tremors, called dyskinesia. The more difficult problem is that the Levadopa begins to lose its effectiveness. When patients start on Sinemet, they take it once a day; after a couple of years, they may need it every two hours.
Fox had a thalamotomy. What is that?
In the 1950s neurosurgeons found that if you make a lesion in an area of the brain called the thalamus—the major connecting part between the cerebral cortex and the rest of the body—you can control tremors. You drill a small hole in the cranium, put a needle through it and send a radio current through it to destroy the thalamus’s nerve cells. But the surgery is only performed when Sinemet—which stops tremors for about 70 percent of the people who use it—doesn’t work.
What about other research?
We’re looking into why dopamine cells die. We know that some toxins kill them, including the chemical MDMA, also known as Ecstasy. Some people who have taken it have come down with Parkinson’s. We’re also looking into the genetics of the disease and whether certain nutrients, such as vitamins E and C, can slow the onset. In addition, we’re hoping to replace dopamine through a surgical technique that implants fetal tissue in patients’ brains.
Is there any hopeful news?
I wouldn’t call having the disease a tragedy. We know so much more about it today than we did 30 years ago. And it is so much more treatable than Alzheimer’s and Lou Gehrig’s disease. People who have Parkinson’s have many, many years to be productive.
When will there be an outright cure?
That depends on what the cause is, and there will probably be several causes. Still, we hope there’s a cure. That’s our goal: to get rid of Parkinson’s in our lifetime.