Not to drag this out, or to try to second guess doctors, but I do have a stake in caring about the subject... my own situation.
First of all, cognitive is the key word... Whether Alzheimers, or dementia, the cause for the decline in cognitive ability, is a study in progress, not a finite definition as with other diseases.
Cognitive
adjective
1.
of or relating to cognition; concerned with the act or process of knowing, perceiving, etc. :cognitive development; cognitive functioning.
2.
of or relating to the mental processes of perception, memory, judgment, and reasoning, as contrasted with emotional and volitional processes.
Note the differentiation.
As we see, just from the postings on this thread, the degree of impairment varies... not just for the severity, but for the time frame of the onset. From my own studies into this, I feel that there is no "predictability " gauge for diagnosis... ie. "Based on what has been observed, we can say that this person will be in later stages of the disease, in one, two, five, or ten years."
Case in point, my mother had symptoms for at least five years, but was able to function quite well until the final three months before passing at age 84. By contrast, a friend, living independently here in our CCRC, was was still playing bridge less than a year ago... entered the memory unit four months ago, and passed away last week... having had no cognition at all for the past month. Not from "physical" problems, but just "going away".
So, I see this as less of a "you have it, or you don't", than as a continuum process, where predictability is chancy at best, and at worst, could lead to unneeded concern, or depression. For the past few years, the nagging concern about my inability to recall names of persons or places caused a mental panic... making the memory blockage worse... compounding the problem. Slowly, this has been ameliorated by acceptance.
As a toddler, the solution was for whooping cough, through the schooldays, for polio, more recently for Aids. While there is some progress, so far no magic pill for dementia.
In short... at this point, I don't see neartime solution, and have planned accordingly. My last two doctors, both of whom I greatly respect, while trying to be noncommittal, mostly agree that diagnosis and predictability are still not written in stone.
Just my opinion...
