I have been thinking about what must be explained by a theory or hypothesis that claims to have solved the PD riddle. I have 15 so far. Can you add others?


There are some characteristics of PD that any hypothesis must explain if it is to be valid. Some I would list include:
1) It is most prevalent in the US and least in the Third World.
2) Historically rare, it seems increasingly common.
3) Traditionally a disease of the old, it seems to strike younger than it once did.
4) Until recently, motor symptoms predominated but now a whole new group of non-motor symptoms unrelated to the substantia nigra are being worked in.
5) The cause must be common since it is so evenly distributed on the macro level, yet it must be rare since it is so unevenly distributed on the individual level.
6) It does not appear to be inherited, yet family clusters occur.
7) Inflammation has a role.
8) Early on, stress response seems unremarkable. Later on they can incapacitate.
9) It is more common among farmers and those who drink milk.
10) It can be intentionally brought on by specific toxins, yet most PWP never encounter them.
11) PWP seem to have experienced unusually high levels of stress pre-adolesence
12) It is commonly preceded by an unusual stress event, such as influenza or loss of a spouse.
13) While a sub-set, there really is a group with a "Parkinson's" personality.
14) Chronologically, symptoms appear in this order- a) loss of olfaction; b) motor; c) stress related.
15) Symptom sets differ greatly and, yet, later stages converge.

There are others, of course, but if a hypothesis is to be complete, it must either explain or dismiss as error these 15 at a minimum. Just a way of saying that Truth wins in the end.