Treatment with sulfonylurea increases intact proinsulin secretion, and in a couple of studies, sulfonylurea treatment was found to be associated with an increased cardiovascular risk. In contrast, several studies have shown that after the introduction of insulin treatment in type 2 diabetic patients intact proinsulin levels and plasma PAI 1 levels decline, indicating not only beta cell protection, but also antiatherogenic properties of insulin. In a recent study, we have shown that treatment with basal insulin in combination with metformin effectively reduces intact proinsulin levels, and that insulin glargine is superior to NPH insulin in controlling postprandial release of intact proinsulin over an entire day.