15 yr old dog. Strange behaviour

Question
Hi. My dog is a 15 yr old staffie/lab/other things mix.  He
has usual problems associated with age (hearing loss,
stiffness etc) When we went for a walk yesterday, he
disappeared whilst I was walking in front of him. I was in
his sight and he has never done this before.  I looked for
him for a while then went home (we were only 5 mins away)
and he was waiting at the door (as I suspected).  However,
he then began walking round the house sniffing at everything
as though it was a strange house.  He would not take
anything to eat or drink and mainly ignored me even when I
sat on the floor and he usually can't resist a cuddle. This
went on for about half an hour then he went away and lay
down and was fine for the rest of the day.  This morning, he
did the same thing again.  Unable to settle and sniffing
round and round.  I took him out for a walk and he sniffed
constantly whilst we were out, going up to every door we
passed and standing as if waiting to be let in (he's never
done this before).  After about half an hour, we met another
couple of dogs and he was fine with them and then seemed to
revert to his usual (non sniffing) self.  On coming home, he  
has again refused to eat or drink but is lying quietly.  I
would be grateful for any advice or explanations you can
give.  Thanks.

Answer
Any time an older dog displays a sudden change in behavior, it's time to see the vet.  Your dog may be experiencing changes in vision, hearing, or cognition.  The vet can explain what, if anything, should be done about his situation.  Some of the suggestions might include: not letting him off leash any more (you can use a long line so that he can trot ahead, but not be able to get lost), making his food more appetizing by moistening it or adding a teaspoon of wet food (to enhance the scent), or taking medication (if he has cognitive problems, arthritis, or some other condition).  Good luck.

Hi,
I was thinking about your dog, and wondering how you made out at the vet.  
Anne