In the DCCT (Diabetes Control and Complications Trial), patients with type 1 dia- betes mellitus were randomized to intensive (mean achieved therapy. During the mean 6.5 years of observation, fewer cardiovascular events occurred in the intensive-treatment group, but the number of events was small, and the difference between groups did not reach statistical significance.574 In a long-term follow-up study of this population, however, inten- sive therapy reduced the risk of cardiovascular events by 42%.579 Intensive glycemic controlled to a reduction in microvascular complications (primarily the need for retinal laser photocoagulation) but not cardiovascular events in the patients with type 2 diabetes mellitus who participated in the UKPDS (UK Prospective Diabetes Study).575 In a secondary analysis, treatment with metformin seemed to confer most of the benefit, whereas treatment with a sulfonylurea was not associated with a significant improvement in any endpoint.599 Patients in UKPDS treated with metformin had a lower median HbA1c (7.4% versus 8.0%) and a 37% reduction in $1 diabetes endpoints compared with those in the conven- tional therapy (diet alone) group.580 In the PROactive (Pros- pective Pioglitazone Clinical Trial in Macrovascular Events) study, patients with type 2 diabetes mellitus and evidence of vascular disease were randomized to pioglitazone or placebo. HbA1c averaged 7.8% at baseline and decreased by 0.3% in the placebo group and by 0.8% in those on active therapy. 