Re: question about possible diabetes
330 is quite a high reading for a nondiabetic unless he just ate half a chocolate cake or something an hour ago.
Even if the sugar load was pretty high, a non-diabetic has sugars in the low 100s two hours after eating.
With his family history, that's "strike 2". If he is obese that's likely strike 3.
He SHOULD get a glucose-tolerance test and check himself out. It is quite common for people to find out they have diabetes when they enter the hospital with angina or a heart-attack, having never known it. It has no symptoms until the awful ones.