Tight Glucose Control Lowers Cardiovascular Disease By About 50 Percent In Diabetes

A significantly lower risk of heart disease can now be added to the list of proven long-term benefits of tight glucose control in people with type 1 diabetes. Researchers announced this finding today at the annual scientific meeting of the American Diabetes Association after analyzing cardiovascular (CVD) events such as heart attack, stroke, and angina in patients who took part in the Diabetes Control and Complications Trial (DCCT) years ago.

“The longer we follow patients, the more we’re impressed by the lasting benefits of tight glucose control,� said Saul Genuth, M.D., of Case Western University. Dr. Genuth chairs the follow-up study of DCCT participants, called the Epidemiology of Diabetes Interventions and Complications (EDIC) study, which has been looking at the long-term effects of prior intensive versus conventional blood glucose control. “The earlier intensive therapy begins and the longer it is maintained, the better the chances of reducing the debilitating complications of diabetes.�The DCCT was a multicenter study that compared intensive management of blood glucose to conventional control in 1,441 people with type 1 diabetes. Patients 13 to 39 years of age were enrolled in the trial between 1983 and 1989. Those randomly assigned to intensive treatment kept glucose levels as close to normal as possible with at least three insulin injections a day or an insulin pump, guided by frequent self-monitoring of blood glucose. Intensive treatment meant keeping hemoglobin A1c (HbA1c) levels as close as possible to the normal value of 6 percent or less. (The HbA1c blood test reflects a person’s average blood sugar over the past 2 to 3 months.) Conventional treatment at the time consisted of one or two insulin injections a day with daily urine or blood glucose testing.In 1993, researchers announced the DCCT’s main findings: intensive glucose control greatly reduces the eye, nerve, and kidney damage of type 1 diabetes. Tight control also lowers the risk of atherosclerosis, according to a study of DCCT participants published in 2003. But what’s most remarkable about intensive control, the researchers say, is its long-lasting value.After 6½ years of the DCCT, HbA1c levels averaged 7 percent in the intensively treated group and 9 percent in the conventionally treated group. When the study ended, the conventionally treated group was encouraged to adopt intensive control and shown how to do it, and researchers began the long-term follow-up of participants. To the researchers’ surprise, the benefits of the original 6 years of intensive control have persisted despite the fact that both groups' HbA1c values have leveled off at about 8 percent after a rise in blood glucose in the intensively treated group and a drop in blood glucose in those formerly on conventional treatment.In results announced today, among the 1,375 volunteers continuing to participate in the study, the intensively treated patients had less than half the number of CVD events than the conventionally treated group (46 compared to 98 events). Such events included heart attacks, stroke, angina, and coronary artery disease requiring angioplasty or coronary bypass surgery. Thirty-one intensively treated patients (4 percent) and 52 conventionally treated patients (7 percent) had at least one CVD event during the 17 years of follow-up. The average age of participants is 45 years; 53 percent are male.“The risk of heart disease is about 10 times higher in people with type 1 diabetes than in people without diabetes. It’s now clear that high blood glucose levels contribute to the development of heart disease,� said David Nathan, M.D., of Massachusetts General Hospital, who co-chaired the DCCT/EDIC research group and presented the results. “The good news is that intensively controlling glucose significantly reduces heart disease as well as damage to the eyes, nerves, and kidneys in people with type 1 diabetes. Tight control is difficult to achieve and maintain, but its advantages are huge.�“The take-home message is that good glucose control should be started as early as possible to delay or prevent serious diabetes-related complications,� said Alan D. Cherrington, PhD, president, American Diabetes Association.Is glucose control just as important for people with type 2 diabetes? “There is a strong and growing body of evidence that everyone with diabetes gains from strict blood glucose control,� said Catherine Cowie, PhD, who oversees EDIC for the National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK).(Source: NIH/National Institute of Diabetes and Digestive and Kidney Diseases: June 2005.)

Related Articles:

• Gene variation may lead to early cardiovascular disease
• Gender differences and heart disease
• Researchers identify gene that regulates glucose levels
• Simple non-lab methods as good as lab tests at predicting cardiovascular disease risk
• Dietary Copper May Ease Heart Disease
• Researchers Find Food-free Route to Obesity
• Study Shows Brain Function Not Impaired By Tight Diabetes Control and Severe Hypoglycaemia
• 2 tests better than 1 for diabetes control
• Study Confirms Intensive Treatment Of Diabetic Patients Significantly Reduces Heart Disease
• NIH Researchers Discover How Insulin Allows Entry Of Glucose Into Cells
• Treatment Of Sleep Apnea Lowers Glucose Levels In Diabetics

Connect

Sign up for free newsletters

Subscribe to RSS feeds

Discuss on Forum

Article Comments

Rate this article