Progression varies enormously with each individual. Age of onset, cause of Parkinson's, health issues other than Parkinson's, stresses, physical and mental activity, social connections, diet, etc. are all variables. Someone who notices a finger twitching at 29 will have a different progression than someone who starts falling at age 80. Some people are self-sufficient for 20 or more years after diagnosis. Some are in a wheelchair 2 years after diagnosis. Dementia doesn't usually begin for several years (unless the person has Lewy's Bodies) and not everyone gets dementia. The Parkinson's Progression Markers Initiative is trying to figure out who gets which symptoms and why and how different groups will progress, but they don't have definitive answers yet. It is a long term research project. If you want to help get the answers, sign up at the Michael J. Fox Foundation website.

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Bill