Does having type 1 diabetes make you lose concentration?

My brother has type 1 diabetes. He has always done something called 'his imagination' where he gallop around like a horse imagining things. He goes out of his way to annoy me and tells tittle tails. He is always watching dvds that are the same even though he watched it the day before. He would keep doing this of he was allowed. If I hum, talk while he is doing his imagination he will get angry and say I can't do it when you talk to me. He can only do it if it is some. Is this to do with his diabetes.

Is he on the spectrum if you don’t know he should probably get tested I have many friends with type 1 diabetes and they do NOT act like this

My brother has type 1 diabetes. He has always done something called 'his imagination' where he gallop around like a horse imagining things. He goes out of his way to annoy me and tells tittle tails. He is always watching dvds that are the same even though he watched it the day before. He would keep doing this of he was allowed. If I hum, talk while he is doing his imagination he will get angry and say I can't do it when you talk to me. He can only do it if it is some. Is this to do with his diabetes.

Whole family other than mum thinks he has ADHD and that he should be tested but her excuse is that is is the diabetes