The UK Prospective Diabetes Study (UKPDS) compared the benefits of intensive glycemic control versus conventional glycemic control in reduction of diabetes-related endpoints. The major benefit was in the reduction of microvascular endpoints. Myocardial infarction was reduced by 16%, but this reduction did not achieve statistical significance. There was no statistically significant reduction in the incidence of stroke or peripheral vascular disease in the intensively treated group compared with the group treated with conventional glycemic control. UKPDS showed that glycemic control management in the context of a clinical trial did not necessarily result in the reduction of macrovascular events, but primarily reduced microvascular endpoints in patients with diabetes.
Reference:

UK Prospective Diabetes Study (UKPDS) Group. Intensive blood-glucose control with sulphonylureas or insulin compared with conventional treatment and risk of complications in patients with type 2 diabetes (UKPDS 33). Lancet 1998;352:837-853.