NIH research among others is supporting the Type III Diabetes Hypothesis . I think this conclusion is very advantageous to recognize, and indicates reversal and cure is possible if approached from this perspective.
The root cause of insulin insensitivity is inflammation. Because Alzheimer's is this result restricted to the brain only, and not the whole body as in Type II Diabetes, then it is likely that the cause is the localized inflammation of the brain caused by microbes.