I'm worried about my grandfather. he is extremely active but tends to repeat stories multiple times in one sitting. he also has poor hygiene. is there something I should look for? I moved to North Carolina, and he lives alone in Connecticut. I'm thinking of moving back just to keep a better eye on him.

It does not sound like dementia that it sounds like he is reminiscing. But the signs are forgetting where you have put things alot. its also described in the dictionary saying: partial or complete deterioration of the brain of mental powers. he will probably need 24/7 around the clock care. I wish you luck with looking after him.