Weighty Matters

Abstract

Type 1 diabetes mellitus, characterized by a deficiency of insulin production owing to damaged pancreatic β-cells, is associated with a 10-fold increase in the risk of cardiovascular disease in comparison with the general population.1,2 Intensive insulin therapy, whether administered by multiple daily injections or continuous infusion via a pump, is the cornerstone of glycemic control in the patient with type 1 diabetes mellitus.3 Much of what we know regarding the benefits of intensive insulin therapy is derived from the Diabetes Control and Complications Trial (DCCT), a trial of patients with type 1 diabetes mellitus who were randomly assigned to either intensive or conventional insulin treatment. Article see p 180 The DCCT enrolled a total of 1441 patients with type 1 diabetes mellitus, beginning in 1983, with final closeout in 1993, for a total of 6.5 years of follow-up. Conventional therapy consisted of 1 or 2 daily injections of insulin with daily self-monitoring and examinations every 3 months, whereas intensive insulin therapy consisted of at least 3 insulin injections per day or external pump therapy with target blood glucose concentrations of 70 to 120 mg/dL fasting, postprandial glucose values of <180 mg/dL, and a target hemoglobin A1c goal in the normal range (<6.05%). The primary trial results showed that intensive therapy achieved a statistically significant lower hemoglobin A1c, evident by the first 3 months of the study, with a closeout A1c of 7.0% in the intensive therapy arm in comparison with 9.0% in the conventional arm. Importantly, those in the intensive insulin therapy arm experienced delayed progression of nephropathy, retinopathy, and neuropathy.4 In the primary trial, the risk of major cardiovascular events trended to significance, although the young age of the participants (mean age, 27 years at enrollment) rendered it difficult to detect a statistically significant …