What is Parkinson Disease?

Parkinson's disease (PD) is a progressive neurodegenerative disorder first described by Dr. James Parkinson in "An Essay on the Shaking Palsy" in 1817.

Some physicians use the term "parkinsonism" in the initial evaluation and diagnosis. Parkinsonism is an umbrella term applied to the clinical syndromes that share the cardinal movement disorders of resting tremor, bradykinesia, rigidity and postural instability.

Idiopathic Parkinson's disease or what is commonly referred to as Parkinson's disease (PD) makes up about 85% of all the parkinsonism syndromes. Idiopathic means unknown cause or origin.

Young Onset Parkinson's disease (YOPD) is a subgroup of idiopathic PD made up of those diagnosed before the age of 50. Although the disease is essentially the same as it is when diagnosed later in life, the issues surrounding the disease are different.

A clinical diagnosis of PD is made by assessing motor function or movement.
The diagnosis is made by the presence of at least two of the four cardinal motor or movement symptoms associated with PD. When the symptoms are present, medications which are known to reduce the symptoms are then often used to increase the likelihood of making a correct clinical diagnosis.

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