Brief Answer:
Probable dementia. Tests necessary to determine which type.

Detailed Answer:
Hello. I read your question carefully and I understand your concern. Thank you for for using HCM for your health inquiries.

The symptoms your are describing are well compatible with dementia which fits also with his age. Dementia could be of different types. The most common one is Alzheimer's disease which has the clinical picture you are describing.

Alzheimer's disease is a chronic neurodegenerative disease. Unfortunately there is no cure but there are treatments which slow down the progression of the symptoms somewhat but eventually the situation will continue to deteriorate.

However before that treatment is started other possible causes of dementia should be excluded first because some of them could be reversible. First a clinical exam is necessary to be sure there is a dementia syndrome and to check for signs of other diseases which can present with dementia. Afterwards several tests are necessary to be done, like routine blood count, routine biochemical panel (blood sugar, liver and renal function tests, electrolytes) as well vitamin B12 level and thyroid panel. Furthermore brain imaging is necessary to exclude causes like a stroke or tumor. Those are the basic tests to be done in a case of dementia. (According to where you live some clinics might make also a lumbar puncture to measure the levels of certain proteins highly specific for Alzheimer's disease, or if there is any suspect of infectious diseases, but are not routine tests).

Only after those other causes have been considered is treatment started with drugs of the cholinesterase inhibitors and NMDA antagonist class (which should be prescribed by your doctor). If on the other hand the test reveals other causes like vitamin B12 deficiency, hypothyroidism, tumor, Parkinson's etc will be addressed accordingly.

Hope to have been of help. I remain at your disposal for other questions.

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