This is my article on Alzheimer's, which may be another classic "Six Blind Men and the Elephant" exercise.
I'm not sure about this, but I believe all the cited "causes" are part of a sequence, something like:
("compromised health/genetics" + "infectious agent" + "old age") > ("overamped immune system" + "compromised brain repair system") > ("Impaired Cognition" + "Amyloid Plaques") > Death
It might be similar to a death from diabetes, which might follow the ("compromised health/genetics" + "sedentary lifestyle") > ("increase in fat cells" + "overamped immune system") > ("inability to produce insulin") > Death
Of course, there are many details.
What's interesting about these sequences is that healthy lifestyle/genetics/decreased inflammation interrupt the sequence, not so much "removing amyloid plaques" or "removing fat" (closing the barn door after the horses got out?).
I'm not a Doctor (I have engineering and Physics degrees, from a Veterinary family), but I read "Science" and "Nature" religiously. I'm always impressed by the researchers, less so by the Big Medical/Pharma (who often serve up expensive "cures in search of a disease").
I'm just trying to use common sense given all the data.
I wrote another about cancer, which is said to be 70% preventable by lifestyle. I believe what we're not being told is that some solid tumors (esp. some lung and pancreatic cancers) still have a horrific survival rate, with little relief in sight.
https://medium.com/@scottvern/the-urgent-frontiers-of-cancer-treatment-cbded6a39894
Its good that you're following up on these threads, you probably won't often get them from the MDs writing on Medium.