About Parkinson's Disease
Parkinson's disease is a progressive nervous system disorder that affects movement.
Symptoms start gradually, sometimes starting with a barely noticeable tremor in just
one hand. Tremors are common, but the disorder also commonly causes stiffness or
slowing of movement.
In the early stages of Parkinson's disease, your face may show little or no
expression. Your arms may not swing when you walk. Your speech may become soft or
slurred. Parkinson's disease symptoms worsen as your condition progresses over time.
Although Parkinson's disease can't be cured, medications might significantly improve
your symptoms. Occasionally, your doctor may suggest surgery to regulate certain
regions of your brain and improve your symptoms.
Symptoms
Parkinson's disease signs and symptoms can be different for everyone. Early signs
may be mild and go unnoticed. Symptoms often begin on one side of your body and
usually remain worse on that side, even after symptoms begin to affect both sides.
Parkinson's signs and symptoms may include:
-
Tremor - A tremor, or shaking, usually begins in a limb, often your hand or
fingers. You
may a rub your thumb and forefinger back-and- forth, known as a pill-rolling
tremor.
Your hand may tremor when it's at rest.
-
Slowed movement (bradykinesia) - Over time, Parkinson's disease may slow your
movement,
making simple tasks difficult and time consuming. Your steps may become shorter
when you
walk. It may be difficult to get out of a chair. You may drag your feet as you
try to
walk.
-
Rigid muscles - Muscle stiffness may occur in any part of your body. The stiff
muscles
can be painful and limit your range of motion.
-
Impaired posture and balance - Your posture may become stooped, or you may have
balance
problems as a result of Parkinson's disease.
-
Loss of automatic movements - You may have a decreased ability to perform
unconscious
movements, including blinking, smiling or swinging your arms when you walk.
-
Speech changes - You may speak softly, quickly, slur or hesitate before talking.
Your
speech may be more of a monotone rather than with the usual inflections.
-
Writing changes - It may become hard to write, and your writing may appear
small.
Causes
In Parkinson's disease, certain nerve cells (neurons) in the brain gradually break
down or die. Many of the symptoms are due to a loss of neurons that produce a
chemical messenger in your brain called dopamine. When dopamine levels decrease, it
causes abnormal brain activity, leading to symptoms of Parkinson's disease. The
cause of Parkinson's disease is unknown, but several factors appear to play a role,
including:
-
Your genes - Researchers have identified specific genetic mutations that can
cause
Parkinson's disease. But these are uncommon except in rare cases with many
family
members affected by Parkinson's disease.
However, certain gene variations appear to increase the risk of Parkinson's
disease
but with a relatively small risk of Parkinson's disease for each of these
genetic
markers.
-
Environmental triggers - Exposure to certain toxins or environmental factors may
increase the risk of later Parkinson's disease, but the risk is relatively
small.
Researchers have also noted that many changes occur in the brains of people with
Parkinson's disease, although it's not clear why these changes occur. These
changes
include:
-
The presence of Lewy bodies - Clumps of specific substances within brain
cells are
microscopic markers of Parkinson's disease. These are called Lewy
bodies, and
researchers believe these Lewy bodies hold an important clue to the
cause of
Parkinson's disease.
-
Alpha-synuclein is found within Lewy bodies - Although many substances
are found
within Lewy bodies, scientists believe an important one is the natural
and
widespread protein called alpha-synuclein (a-synuclein). It's found in
all Lewy
bodies in a clumped form that cells can't break down. This is currently
an important
focus among Parkinson's disease researchers.
Risk Factors
Risk factors for Parkinson's disease include:
-
Age - Young adults rarely experience Parkinson's disease. It ordinarily begins
in middle
or late life, and the risk increases with age. People usually develop the
disease around
age 60 or older.
-
Heredity - Having a close relative with Parkinson's disease increases the
chances that
you'll develop the disease. However, your risks are still small unless you have
many
relatives in your family with Parkinson's disease.
-
Sex - Men are more likely to develop Parkinson's disease than women.
-
Exposure to toxins - Ongoing exposure to herbicides and pesticides may slightly
increase
your risk of Parkinson's disease.
Diagnosis
There is no single test to conclusively diagnose Parkinson’s disease (PD). However,
there are various symptoms and diagnostic tests used in combination. Making an
accurate diagnosis of Parkinson’s, particularly in its early stages, is difficult,
but a skilled practitioner can come to a reasoned conclusion that it is PD. It is
important to remember that two of the four main symptoms must be present over a
period of time for a neurologist to consider a PD diagnosis:
-
Shaking or tremor
-
Slowness of movement, called bradykinesia
-
Stiffness or rigidity of the arms, legs or trunk
-
Trouble with balance and possible falls, also called postural instability
Often, a Parkinson’s diagnosis is first made by an internist or family physician.
Many people seek an additional opinion from a neurologist with experience and
specific training in the assessment and treatment of PD - referred to as a movement
disorder specialist.