Today, it seems self-evident that hyperglycemia is the causative agent for diabetic complications. However, this concept was firmly established only in the 1990s with 2 seminal studies: DCCT (Diabetes Control and Complications Trial)1 in type 1 and UKPDS (UK Prospective Diabetes Study) in type 2 diabetes.2 The follow-on studies to these trials described the phenomenon of metabolic memory or the legacy effect: that past hyperglycemia leads to sustained increase in the risk of end-organ complications and death long after glucose control has been established.