My Boyfriend Age 62, Passed Out Today And Is Not

My boyfriend age 62, passed out today and is not going to the hospital to check it out until tomorrow morning. He said his blood sugar level was over 300, that was this morning. should we be concerned?? He had an issue 4 years ago and had to be hospitalized for the first time due to his blood sugar. He was put on medication but since been taken off. What should we do? go to the ER?