moms boyfriend confused, not a stroke......?

my moms boyfriend has a history of high blood pressure and takes bp medication......we took him to the er last thursday, his bp was 199/99.......they gave him meds, he went and saw his doc and they switched his old meds to the ones suggested by the er doc.......on tuesday my mom went to see him at his home and he was confused.....calling her by his deceased wife.s name and not responding to things correctly.......she called 911 and they took him to the hospital.....ct was completely normal.....mri was completely normal........bloodwork only showed mild dehydration-probably because he had been laying around for who knows how many hours and he is 76 years old......he left the hospital against medical advice the next day and now he seems fine......other than the high blood pressure that is in the process of being medicated, he is completely healthy, he comes over to our house to fix stuff, he is an avid reader, him and my mom go dancing at least twice a week