MELVILLE, N.Y. — Keeping tight control of blood sugar can halve Type 1 diabetics' risk of cardiovascular disease, one of the deadliest complications of the condition, doctors found in an analysis reported today.
"This is a rare instance of a happy ending," said Dr. Saul M. Genuth, chairman of a research project initiated in 1983. Genuth and a nationwide team of researchers studied more than 1,000 patients with Type 1 diabetes and found they gained a health-enhancing advantage when they rigorously controlled their blood-sugar levels.
The equivalent of five or six injections of insulin a day, compared with the conventional one or two injections, reduced the risk of heart disease and stroke by 50%. Genuth said it did not matter whether the insulin was delivered by injection or pump: "When you bring your blood glucose as close to normal as possible, that is what counts most."
In 1993, Genuth and colleagues reported that such intensive glucose control sharply reduced the eye, kidney and nerve damage that could accompany Type 1 diabetes. Since then, doctors have been examining how rigorous control reduces heart attacks and strokes, two major causes of death in diabetics.
"The risk of heart disease is 10 times higher in people with Type 1 diabetes than in people without diabetes," said Dr. David M. Nathan of Massachusetts General Hospital, who co-chaired the study. "Maintaining tight control is difficult, but its advantages are huge."
The findings are reported in today's issue of the New England Journal of Medicine.
Type 1 diabetes is an autoimmune disease in which the body destroys insulin-producing cells in the pancreas. Without insulin, blood sugar careens out of control.
A nuance separates Type 1 diabetes from Type 2, which often emerges in middle age. In Type 2, many patients produce some level of insulin but the body is unable to effectively use it. That form of the disease often can be controlled through diet and/or medication.
Regardless of type, diabetes is the leading cause of blindness, kidney failure and amputations in adults, and a major cause of cardiovascular disease. About 21 million people in the United States have diabetes, mostly Type 2.