The burden of uncontrolled A1C in type 1 diabetes: 30 years of insights from the DCCT/EDIC study

In the 1990s, the results of the Diabetes Control and Complication Trial (DCCT) set the standard for the management of type 1 diabetes.1 The trial unequivocally demonstrated that intensive diabetes therapy, based on multiple daily injections of insulin or insulin pump, frequent monitoring of blood glucose, and specific glucose targets, resulted in lower Hemoglobin A1C (A1C) and less microvascular complications than conventional therapy.1 After the trial closeout, patients were encouraged to adopt or to continue the intensive treatment regimen with their own healthcare providers, and their outcomes were followed up in the Epidemiology of Diabetes Interventions and Complications (EDIC) observational study.2 The differences in A1C between the original arms of the DCCT disappeared few years later. [...]it might be overly optimistic on the gains attainable through intensive therapy and overly negative on the consequences of prolonged conventional therapy. [...]the more subtle evaluations of varying cost-effectiveness scenarios, based on the cost of treatment used in the DCCT or in modern practice, of intensive therapy performed with pumps and continuous glucose monitoring or without, do not account for the potential differences in complication rates, hypoglycemic events and quality of life achieved by these alternatives, but only for differences in the cost the associated with providing them, further moving the cost-effectiveness simulation into a speculative realm.