Parkinson's disease, also known as shaking palsy and paralysis agitans, is defined as a progressive neurological disorder
that results when nerve cells in part of the basal ganglia (called the substantia nigra) degenerate, reducing the production
of the neurotransmitter dopamine and the number of connections between nerve cells in the basal ganglia. This degeneration
causes movement impairments so people with Parkinson's often experience muscle rigidity, trembling, difficulty walking
and problems with balance and coordination. Parkinson's is a progressive disease, meaning that the symptoms become worse over
time. The disease was first formally described by British physician James Parkinson in 1817, but probably existed
a long time before that. There are two main types of Parkinson's disease: Early-onset Parkinson's which occurs before
50 and accounts for approximately 5 to 10% of all cases and late-onset Parkinson's which occurs after 50 and accounts
for most cases of the disease.
Parkinson's disease affects people on a worldwide scale. Today
in Canada there are approximately 100,000 people suffering from the disease. The medical community estimates that there
are approximately 120 million people with Parkinson's around the world. The disorder appears to be more common in
men than woman and is more prevalent in older people. The average age of onset is about 60 years old. Prevalence
and incidence increase with advancing age. Because no definitive tests exist for determining if someone has Parkinson's,
it is often difficult to estimate the number of people in Canada and the world with the disease.
The above graph shows how age affects the number
of people with Parkinson's disease. It is also compares male and female statistics.
What Causes Parkinson's Disease?