I came across this article which says that -
“The risk estimates for Parkinson’s disease in autistic people range from 15 to 20 percent, compared with about 1 percent in the general population.”
The search for a link between autism and neurodegenerative conditions | Spectrum | Autism Research News (spectrumnews.org)
Given that about 2% of the population is autistic, and most autistic adults remain unidentified, I wonder how many people with Parkinson’s are autistic?
I know it has been a while since you posted this thread, but I just wanted to chime in with some information that I thought would be helpful to this topic.
Unfortunately we don’t know how many people in the UK have autism and Parkinson’s. But in some cases symptoms of autism crossover with symptoms of Parkinson’s such as bradykinesia (slowness of movement).
There have been some research studies looking into the link between autism and Parkinson’s and the results have shown that there may well be an increased frequency of Parkinsonism in older people with Autism. However the studies that have looked into this have been small so there needs to be further large scale research to replicate the results before definitive conclusions can be made.
I hope you find this helpful.