Blood vessels are the unifying thing. Most established risk factors for Alzheimer's relate to blood vessel health (hypertension, hyperlipidemia, diabetes, smoking), proxies for bad blood vessels (heart attacks, congestive heart failure, stroke, peripheral artery disease, kidney failure) and aging. Sure enough there is a thing that builds up in blood vessels as we age called medin that seems to be some kind of detritus from stuff that holds vascular cells together. And sure enough there is evidence that blood vessels with medin adjacent to brain lead to amyloid plaques/tangles we have been chasing for decades, but as others have called it, those plaques are the smoke, not the fire.

I suspect when you read about viruses/inflammation being linked to neurodegenerative processes, you're really just talking about leaking medin/other crap into the brain.

I believe an AI study concluded that the strongest risk factor for developing dementia was leaking proteins in the urine. Because proteins aren't supposed to be leaking from anywhere, so if they are leaking in the urine, then they are probably leaking in the brain.

And strongest risk factor for that kind of leaking? Diabetes.

If I were treating stocks like gambling, I would invest it all in any pharmaceutical company that is developing antibody to medin