Parkinson disease involves the nervous system, specifically, movement
and control of muscles. Parkinson disease affects more than 1 million individuals
in the United States. Because it is more common in older persons, the incidence (number of new cases) of Parkinson disease is
increasing as the population grows older. Parkinson disease was first described
in 1817 and was originally called "shaking palsy." Medical researchers later
discovered that parkinsonian symptoms were due to degeneration of nerve cells
in an area of the brain called the substantia nigra.
These cells supply dopamine, a chemical that modulates
movement, to other areas of the brain called the basal ganglia. Parkinson disease is progressive and leads to severe limitations
in activity and quality of life if the disorder is not treated. Neurologists (doctors who specialize in treating diseases of the nervous
system) and neurosurgeons (doctors who specialize
in surgery of the nervous system) individualize each person's treatment to
manage the symptoms and slow the progress of Parkinson disease. The January
21, 2004, issue of JAMA includes an article about
treatment of Parkinson disease.
Rigidity—stiffness of arms, legs, face, and
posture
Tremor—shaking of the head, face, arms, legs,
and hands; not everyone who has Parkinson disease has a tremor
Slowness of movement—also called bradykinesia
Instability—unstable gait, poor balance
Levodopa (a synthetic medication) replaces dopamine
for patients with Parkinson disease, improving symptoms of tremor and rigidity.
Carbidopa helps reduce adverse effects of levodopa
and increases the amount of dopamine in the brain (and not in the rest of
the body).
Several other medications are available to decrease
symptoms or slow the progression of Parkinson disease.
Antidepressants may be prescribed if depression
occurs.
Pallidotomy—a probe
delivering electrical current is used to create a permanent lesion (scar) in a specific area of the brain (the globus pallidus) to lessen rigidity, tremor, and abnormal movements
(dyskinesias).
Thalamotomy—electrical
current creates a small, permanent lesion in the area of the brain called
the thalamus. This helps reduce tremor and rigidity.
Deep brain stimulation—an
electrode is placed into a specific deep brain structure. Electrical current
is delivered continuously to control tremor, rigidity, or bradykinesia. This
requires a small generator (like a heart pacemaker) to be placed under the
collarbone.
An operation may help persons with Parkinson disease, especially if
medical therapy has failed to slow the disease process or if intolerable adverse
effects occur from medications. Because these operations involve the brain,
there are significant risks involved. The risks and benefits of surgical therapy
should be discussed with a neurologist and neurosurgeon. This type of surgery
does not replace medical therapy, but it may lessen the amount and types of
medications a patient takes.
To find this and previous JAMA Patient Pages, go to the Patient Page
link on JAMA's Web site at http://www.jama.com. Many are available in English and Spanish. A Patient Page on Parkinson
disease was published in the October 18, 2000, issue.
Sources: National Institute of Neurological Disorders and Stroke, American
Parkinson Disease Association, National Parkinson Foundation, Parkinson's
Disease Foundation
The JAMA Patient Page is a public service of JAMA. The information and recommendations
appearing on this page
are appropriate in most instances, but they are not a substitute for medical
diagnosis. For specific information concerning your personal medical condition, JAMA suggests that you consult your physician. This page
may be photocopied noncommercially by physicians and other health care professionals
to share with patients. Any other print or online reproduction is subject
to AMA approval. To purchase bulk reprints, call 718/946-7424.
TOPIC: NEUROLOGICAL DISEASES