Excessive Weight Gain and Effects on Lipids With Intensive Therapy of Type 1 Diabetes

To the Editor.—The study by Dr Purnell and colleagues¹ also has important implications for rethinking the role of intensive glucose control with insulin in type 2 diabetes. Previous clinical trials^2- 3 and now the study by Purnell et al¹ suggest that treatments that raise insulin levels, increase weight and worsen cardiovascular risk factors despite improving glycemia. In 3 European cohorts totaling 17,000 nondiabetic working men, the all-cause mortality was significantly greater for those who had the highest glucose intolerance but not high enough for a diagnosis of diabetes.⁴ Duration rather than severity of glycemia is a greater risk factor for coronary artery disease (CAD), suggesting a shared underlying pathophysiologic process, endothelial cell dysfunction. Enderle et al⁵ suggest that a longer period of undetected diabetes rather than poor glucose control impairs endothelial-dependent vasodilatation in type 2 diabetes.