now...just some guess work here as i am more surgically oriented as a nurse...but i think the yearly bloodwork he does would be a overview of health and whats a potential for something going on, sometimes the first indication that something is awry... general blood count, chemistries (like glucose, potassium and calcium levels...) maybe some liver function tests and cholesterol. bloods probably arent drawn more than once a yr unless warrented.
as for the ..."Take charge of your Diabetes" diet that he gave u...i would guess that since u had issue with blood pressure and he got you on a more strict diet...and as i can remember i think the 'diabetic diet' thing is really the way everyone who wants to be the basic level of healthy should be eating for a balanced healthy diet (not speaking of ppl who need special diets or are bulking on certain things for exercises)... i bet thats why he gave u that diet (diabetic diets are often refered to as the calories and ADA...like u were 1500 calorie i think.)