Brief Answer:
Read below.

Detailed Answer:
I read your question carefully and I understand your concern.

You make a legitimate point there. While it is rare for Alzheimer's to be familial, most cases are sporadic, having it at a relatively early age as the 60s and in two generations does raise concern for it being familial.

On the other hand keep in mind that at times depression can affect cognitive functioning. Low thyroid function as well is a well know cause for cognitive impairment. So having cognitive impairment shouldn't be seen as a sentence. It is important that she is evaluated by a neurologist to make the distinction, to have neuropsychological testing which would evidence whether there is impairment and in which areas. The type of impairment would indicate whether it is Alzheimer's or another type.
Also brain imaging might also give clues (while not making the diagnosis alone) by showing atrophy and low function of certain brain areas.
Today for suspected familial cases there is also genetic testing for certain know mutations which are related with familiar Alzheimer cases. Naturally these are expensive tests recommended only if neuropsychological testing and imaging suggest the diagnosis.

Now I understand it is difficult to implement those steps without the agreement of your son in law. As I can't talk to him unfortunately, it is important for you to talk with him in a patient manner, perhaps show him information from internet on Alzheimer cases before 65 being considered of early onset and often in the setting of a genetic issue. Try to present it only as one other option to be considered alongside depression to make sure, not as a foregone conclusion, tell him that neuropsychological testing after all is only a type of questionnaire not an invasive procedure. Of course since you say she has only mild impairment you can discuss the issue directly with your daughter as well or with your grandchildren if she has any and you think they might exercise some influence.

I remain at your disposal for further questions.

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Brief Answer:
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Detailed Answer:
Thank your for the additional info.

It is a little difficult for me to give information on costs as I practice in Europe where insurance practices and fees do vary a lot even between neighboring countries let alone compared to US.
But of course not all the tests I mentioned might be necessary. The first step is neurological exam and neuropsychological testing. If those result normal then further tests like imaging and genetic testing might not be necessary at all, as I said depression and anxiety may mimic at times memory impairment as they affect concentration which is necessary to retain information.

So neuropsychological testing, which provides a subjective evaluation of cognition is the first step. Now there are screening tests which can be done in 15 minutes during the course of a neurologic consultation, so the fee should be that of the consult only. At times more prolonged and detailed test which are done separately and would require extra fees. But the basic step shouldn't cost so much, a neurological consult, where it'll go from there depends on the findings, if screening test normal it might be left there.

I hope to have been of help.

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Brief Answer:
You're welcome.

Detailed Answer:
Well Mayo is certainly a great option well famous worldwide. You are bound to get the best expertise there. Hopefully you are wrong and she doesn't have Alzheimer's.

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