For several reasons. Parkinson's disease is a neurodegenerative disease mostly causing degeneration of the midbrain, caused by a decreased dopamine level.
One thing an MA needs to remember is that in advanced stages of the disease, Parkinson's can result in poor historical accuracy from the patient. They may have some cognitive deficiencies. Additionally severe stages of the disease cause a loss of our sense of balance and severe tremors, so the patient may need your support when standing and moving.
