Thanks fletch, that's an excellent research summar
Post# of 1460
A couple of comments:
Studies have shown that there is a strong link between developing Parkinson's disease in middle age and chemical exposure at an earlier age. So it is not accurate to say that a genetic tendency is the ONLY possible cause. However it is possible that someone who did not have the genetic tendency would not developed Parkinson's, but might have had other bad effects -- or no effects -- from the same chemical exposure. As the poster said, the human body is an incredibly complex system and I doubt that we'll know absolute causes and mechanisms in the lifetime of anyone reading this board today.
As far as the amyloid theory, I think that the reason that all the drugs trying to clear out amyloid plaques have FAILED or made things worse is indeed the band-aid theory --
the brain's defense against the disease is to form the plaques, the way that clots form to stop bleeding from a cut. When you get rid of the plaques, it's like ripping the clots off a cut -- the bleeding starts again. That would explain why some of the experimental drugs ACCELERATED the decline for patients.
And, for both Parkinson's and Alzheimer's, I think that future research will show that some people who have been diagnosed with those diseases have other diseases that have similar symptoms, and have been lumped into the category together. Particularly with Alzheimer's, there is radical difference between people in symptoms, speed of decline, and the way that it affects personality while they are still somewhat functional. Some people who were previously normal-behaving people become angry and violent; others who may have been angry or nasty before become nicer and less nasty when they get the disease.
I think that there are many different causes for dementia systems, and lumping them all together in the category of "Alzheimer's" is another reason why so many clinical trials have had mixed results. If you're testing a drug for one disease on people who have different types of disease, that drug is only going to help the ones who have the disease you're trying to treat.
We desperately need a test for Alzheimer's that can diagnose it in the living. Fortunately it looks like there is some progress in that direction. The sooner, the better.