Dementia is a general term for a wide range of similar mental problems,
Alzheimers is a (slightly) more specific term. However, Az is usually only
diagnosed after other types of demetias have been ruled out. So, they look
and see if you have one of many different types of dementia, if you dont
then they label it Az.

Dementia is term for a symptom. It isn't a diagnosis of illness. Its
like saying someone has a fever or a rash. It is just a term to label
a set of observable conditions - it does not describe what the
underlying CAUSE is.

Just as there are dozens and dozens of things that can cause a fever
or a rash, there are also dozens and dozens of things that can cause
dementia - which means mental confusion.

If a doctor says Mrs. Jones has dementia, it just means she is
confused, forgetful, not making sense etc. If you get told that about
someone you love, you say, that's nice, we already figured that part
out, but what is it FROM??? By the way, old age isn't a cause. The
underlying cause is the important part that will tell you what can be
done about it. There are illnesses that cause dementia that can be
reversed. There are causes of dementia that can't be cured, but can be
stopped from causing further damage. And then there things like
Alzheimer's which are relentlessly progressive, but can be slowed down
a bit. There are even dementias that absolutely MUST NOT be treated
with certain drugs because they make the person worse, rather than
better.

So  you want to know that the person has dementia due to a stroke, or
due to a head injury, or due to a vitamin deficiency, or due to
Alzheimer's etc. etc.. Knowing the underlying cause is also important
because different diseases that cause dementia will produce different
patterns of mental changes and different sets of behaviours over
different time horizons. If you want to be ready for what might happen
next, it matters to the family if the person has Pick's disease vs.
Alzheimer's disease or whatever. You need to be able to understand
what is going on and what the prognosis is so you can make realistic
plans.
is important.

Any doctor who tells you different and refuses to investigate further
is a doctor to fire.It is always worth a proper diagnosis and
evaluation - after all, if the person was 35 instead of 75 or 80, you
know they would get that kind of attention.

Mary G.

Thank you Tumbleweed and Mary Gordon for answering my question.
Much appreciated.