Intensive Glucose Control Halves Complications of Longstanding Type 1 Diabetes
The Diabetes Control and Complications Trial was a landmark clinical study in people with type 1 diabetes, formerly called juvenile-onset diabetes or insulin-dependent diabetes. Funded by the National Institutes of Health, it compared the effects of standard control of blood glucose with intensive control on the development of common diabetes complications. The study found that keeping blood glucose levels as close to normal as possible slows the onset and progression of the eye, nerve, and kidney damage of diabetes. Updated information shows improved long-term outlook.
Green: Researcher's findings show that for people with type 1 diabetes, near-normal control of glucose beginning as soon as possible after diagnosis greatly improves the long-term prognosis of the disease. Dr. David M. Nathan, of Massachusetts General Hospital and Harvard Medical School, who co-chaired the Diabetes Control and Complications Trial, now co-chairs a follow-up study.
Nathan: The Diabetes Control and Complications Trial, which was initiated more than 25 years ago, was designed to determine whether intensive therapy aimed at achieving glucose levels as close to the non-diabetic range as we could would result in a change in the development or progression of diabetes complications.
Green: Intensive glucose control in fact halves complications of longstanding type 1 diabetes.
Nathan: Intensive therapy is now the standard so that's what all patients should be recommended to follow with type 1 diabetes.
Green: The Epidemiology of Diabetes Interventions and Complications follow-up study also found that the outlook for people with longstanding type 1 diabetes has greatly improved in the past 20 years due to a better understanding of the importance of intensive glucose control as well as advances in insulin formulations, insulin delivery, glucose monitoring, and the treatment of cardiovascular risk factors. Dr. Nathan continues to follow participants to determine the long-term effects of prior intensive versus conventional blood glucose control.
Nathan: So our patients now have been followed throughout about 30 years duration of diabetes and what the new paper shows, the one that has appeared in the Archives of Internal Medicine, that patients who are treated with modern day methods with intensive therapy have actually a very low risk of developing the severe outcomes that we used to associate with type 1 diabetes.
Green: Type 1 diabetes complications include eye damage, kidney damage and cardiovascular disease events like heart attack and stroke. In the Diabetes Control and Complications Trial, conducted from 1983 to 1989, intensive therapy meant at least three insulin injections a day or use of an insulin pump along with self-glucose monitoring at least four times a day to keep glucose in the near normal range. Dr. Nathan explains that patients in the study were randomly assigned to two groups. One aimed for a hemoglobin A1C in the normal range based on an A1C test which shows a person's average blood glucose over time.
Nathan: We demonstrated that the intensively treated group, which maintained a hemoglobin A1C of approximately 7% when compared with the conventional treatment group that had an average hemoglobin A1C of about 9% reduced the development of eye disease, kidney disease, and nerve disease by as much as 76%.
Green: Researchers conclude that while tight control is difficult to achieve and maintain, its benefits have changed the course of diabetes. Not only did intensive glucose control halve the rates of eye and kidney damage, but the rates of vision loss and kidney failure were much lower than had been seen historically. For more information on this study, visit www.niddk.nih.gov. This is Alex Green IV, National Institutes of Health, Bethesda, Maryland.
About This Audio Report
Reporter: Alex Green IV
Sound Bite: Dr. David M. Nathan