It might be not dementia but some treatable condition after all!
I often read about conditions that can give the appearance of early stage dementia, such as low blood sugar, vitamin deficiency, etc. I'm posting this to encourage caregivers to get every possible test for the patient before giving up and concluding that it's something untreatable or 'just old age' etc.
A very big good thing has happened. The VA doctors have been telling us all along that my 70 year old husband probably does not have dementia -- that his problems with memory, speech, etc etc can all be accounted for by a combination of his known diagnosed conditions: diabetes, heart failure, PTSD, depression, lack of sleep because of various pains, etc. This last week all of those happened to have good phases at once -- and during this short time he has been back to his old health! Well, he does tire and have to eat frequently, but mentally and emotionally and energy-wise he's back. I told him it's like being 40 instead of 70. Well, 50 or 60, anyway. We spent a day planning a gardening project, the past seemed like a bad dream. I forgot all the bad times, and we immediately had one or our old quarrels about the details of teh compost bin!
I've seen demented people perk up for special occasions, but this is different. This is like when sometimes he would come out of a counselling session much improved for a couple of hours, so maybe depression was a big part of it. Anyway, even with no counselling lately, this good time has lasted about a week now!
I know that it will probably all crash when one or another of his illnesses goes into a worse phase (even one night of insomnia would knock him out for a day or two), but this is giving us a lot of hope that it's worth plugging away at these small problems because when small problems clear up, a big improvement can sometimes happen.
We've been lucky here because he has full VA medical benefits. They are very generous with diagnostic scans, blood tests, etc etc. If all he had was Medicare, we probably would not have done all this testing, because of the co-pays. Also continued tweaking of details of treatment has paid off. I've been depressed and hopeless from dealing with all this, so I wouldn't have pushed for enough tests and treatments without VA support.
(And Carol here gave me the tip that a small difference in the 'same' drug can make a big difference in its effect. So there is always something new to learn.)