Physician Focus: October 2011
By Anna Hohler, M.D. and Samuel Frank, M.D.
Despite remarkable discoveries and technological advances over
the years, medicine still has its mysteries, and Parkinson's
disease is among them.
A neurological disorder of the brain that affects a person's
muscle control and bodily movements, Parkinson's is named for the
English doctor, James Parkinson, who first identified and described
the condition in 1817 in "An Essay on the Shaking Palsy."
The symptoms and onset of the disease appear slowly and
gradually, usually without the patient's knowledge, a fact noted by
Dr. Parkinson nearly 200 years ago. "So slight and nearly
imperceptible are the first inroads of this malady," he wrote, "and
so extremely slow its progress, that it rarely happens that the
patient can form any recollection of the precise period of its
commencement."
Nearly one million people in the United States suffer from the
condition, and its incidence is growing: 50,000 to 60,000 new
cases are being diagnosed each year. It is a disorder affecting an
older population, usually beginning in people 60 years of age and
up.
Parkinson's disease causes tremors or shaking of the face, arms,
or legs; stiffness in the limbs or trunk; slowness of movement; and
poor balance and coordination. It is a chronic condition,
persisting over a long time, and it is progressive, with symptoms
growing worse over time.
The mystery of Parkinson's is its cause. While the disease is
known to be intrinsic to the brain, where degeneration occurs in
certain parts of the brain, the specific causes of the condition
are unknown. Several theories about causes do exist,
including genetic predisposition, environmental exposure -
especially to heavy metals or pesticides - and traumatic head
injury.
This lack of a known cause and the absence of testing to
pinpoint the disorder - there's no blood test, X-ray or other
imaging test to diagnose the disease - make it difficult for
physicians to get an accurate diagnosis.
Physicians must look beyond the tremors, stiffness or slow movement
and examine how the condition may be affecting aspects of a
patient's daily life. Other indications of the disease may include
a decrease in animation of the face, or "poker face," slowness of
speech, difficulty with handwriting, problems with sleep, or issues
surrounding mood. Those conditions, along with the tremors and
stiffness, combined with an extensive medical history and physical
examination, help lead physicians to a proper diagnosis.
One known characteristic of the condition is a dramatic drop in
the amount of dopamine in the brain. Dopamine is a neurochemical
that sends signals between neurons and helps regulate movement,
among other functions. Replacing the dopamine lost over time with
medication is part of the treatment for patients with Parkinson's
disease. Other medications may be prescribed as well, and in some
cases, surgery may be appropriate. This surgery - called deep brain
stimulation - involves implanting electrodes into the brain that
are then programmed to reduce tremors and slowness of
movement.
Although no cure for Parkinson's currently exists, research
continues, particularly for a medication than can slow the
progression of the disease. Current therapies are good at treating
the symptoms of Parkinson's, but nothing is now available to slow
its progression.
The good news is that the medications and therapies available
now allow patients to live a full life. In diagnosing and treating
patients, physicians approach each person individually, tailoring
their medications and treatments. Patients that stay in close
contact with their physicians, stay with proper medications and
have those adjusted if and when necessary, and live a healthy
lifestyle with proper diet and exercise, can have a good quality of
life.
To learn more about Parkinson's, including early warning signs
and living with the disease, visit the American Parkinson Disease
Association at www.apdaparkinson.org And
for a video discussion, visit www.physicianfocus.org
Anna Hohler, M.D. and Samuel Frank, M.D. are board-certified
neurologists at Boston Medical Center who specialize in treating
Parkinson's patients. Physician Focus is a public service of the
Massachusetts Medical Society. Readers should use their own
judgment when seeking medical care and consult with their physician
for treatment. Send comments to PhysicianFocus@mms.org
