What do you want to tell people, and who do you want to tell it to?
The challenge is to find their e-mail addresses - every PD org, every PD blog, and every PD clinic, every PD drug maker, every PD research group, every PD doctor, and.... every PD newbie.
And then send them very little. Not having the resources to send a lot. Just once in awhile, send out a broadside, or a teaser, or a declaration; maybe just one topic at a time.

Parkinson's experts want to have a word with you, about (place topic here).
(We, who have Parkinson's, are offering you expertise you will find nowhere else - the highly specialized knowledge and experience of those who have the disease.)