What is Parkinson's Disease?
Parkinson's disease (PD) belongs to a group of
conditions called motor system disorders, which
are the result of the loss of dopamine-producing
brain cells. The four primary symptoms of PD are
tremor, or trembling in hands, arms, legs, jaw,
and face; rigidity, or stiffness of the limbs
and trunk; bradykinesia, or slowness of
movement; and postural instability, or impaired
balance and coordination. As these symptoms
become more pronounced, patients may have
difficulty walking, talking, or completing other
simple tasks. PD usually affects people over the
age of 50. Early symptoms of PD are subtle and
occur gradually. In some people the disease
progresses more quickly than in others. As the
disease progresses, the shaking, or tremor,
which affects the majority of PD patients may
begin to interfere with daily activities. Other
symptoms may include depression and other
emotional changes; difficulty in swallowing,
chewing, and speaking; urinary problems or
constipation; skin problems; and sleep
disruptions. There are currently no blood or
laboratory tests that have been proven to help
in diagnosing sporadic PD. Therefore the
diagnosis is based on medical history and a
neurological examination. The disease can be
difficult to diagnose accurately. Doctors may
sometimes request brain scans or laboratory
tests in order to rule out other diseases.
Is there any treatment?
At present, there is no cure for PD, but a
variety of medications provide dramatic
relief from the symptoms. Usually, patients
are given levodopa combined with carbidopa.
Carbidopa delays the conversion of levodopa
into dopamine until it reaches the brain.
Nerve cells can use levodopa to make
dopamine and replenish the brain's dwindling
supply. Although levodopa helps at least
three-quarters of parkinsonian cases, not
all symptoms respond equally to the drug.
Bradykinesia and rigidity respond best,
while tremor may be only marginally reduced.
Problems with balance and other symptoms may
not be alleviated at all. Anticholinergics
may help control tremor and rigidity. Other
drugs, such as bromocriptine, pramipexole,
and ropinirole, mimic the role of dopamine
in the brain, causing the neurons to react
as they would to dopamine. An antiviral
drug, amantadine, also appears to reduce
symptoms. In May 2006, the FDA approved
rasagiline to be used along with levodopa
for patients with advanced PD or as a
single-drug treatment for early PD.
In some cases, surgery may be appropriate if
the disease doesn't respond to drugs. A
therapy called deep brain stimulation (DBS)
has now been approved by the U.S. Food and
Drug Administration. In DBS, electrodes are
implanted into the brain and connected to a
small electrical device called a pulse
generator that can be externally programmed.
DBS can reduce the need for levodopa and
related drugs, which in turn decreases the
involuntary movements called dyskinesias
that are a common side effect of levodopa.
It also helps to alleviate fluctuations of
symptoms and to reduce tremors, slowness of
movements, and gait problems. DBS requires
careful programming of the stimulator device
in order to work correctly.
What is the prognosis?
PD is both chronic, meaning it persists over
a long period of time, and progressive,
meaning its symptoms grow worse over time.
Although some people become severely
disabled, others experience only minor motor
disruptions. Tremor is the major symptom for
some patients, while for others tremor is
only a minor complaint and other symptoms
are more troublesome. No one can predict
which symptoms will affect an individual
patient, and the intensity of the symptoms
also varies from person to person.
What research is being done?
We are using electrical
stimulation with nanaotechnology and
electropolation to help parkinson patients.