There is a range of research to suggest that Alzheimer's is a metabolic disorder with high level similarities to type 2 diabetes. You might look up "type 3 diab

There is a range of research to suggest that Alzheimer's is a metabolic disorder with high level similarities to type 2 diabetes. You might look up "type 3 diabetes" - which is not an official designation, but sufficiently discussed in the research community and associated with Alzheimer's disease that when a different form of (definitely) age-related diabetes was discovered recently, it had to be called type 4. Equally, don't look for single causes. There are multiple contributing factors, all of which interact with one another, and many of which have multiple causes. E.g. amyloid buildup can be in part failure of clearance by immune cells, in part failure of drainage of cerebrospinal fluid through the cribiform plate, in part generation by lingering spirochete infection, etc.