Effect of Glycemic Exposure on the Risk of Microvascular Complications in the Diabetes Control and Complications Trial—Revisited

A1C explains virtually all of the difference in risk of complications between the intensive and conventional groups, and a given A1C level has similar effects within the two treatment groups. While other components of hyperglycemia, such as glucose variation, may contribute to the risk of complications, such factors can only explain a small part of the differences in risk between intensive and conventional therapy over time.