A nine-year study has determined that if insulin-dependent diabetics monitor their blood sugar levels four or more times a day and then adjust their insulin intake accordingly, they can prevent or radically slow the development of eye, kidney or nerve problems.
Conventional treatment now calls for insulin-dependent diabetics to take a daily blood sugar test and one or two insulin shots a day.
"This is probably the most important study to come out in the diabetes arena in the last 25 years," said Kenneth Farber, executive director of the Juvenile Diabetes Foundation, based in New York. "Diabetics truly have a way now to do something about eye, kidney and nerve disease."
The study, presented Sunday at the annual meeting of the American Diabetes Association in Las Vegas, looked only at insulin-dependent, or Type I, diabetes, the rarer form affecting about 1.4-million Americans. But Farber and others think it could ultimately apply to non-insulin-dependent, or Type II, diabetes, afflicting another 13-million people nationwide.
"The standard of care should be to try to get the blood glucose level as close to normal as possible," said Dr. Xavier Pi-Sunyer, president of the American Diabetes Association, based in Alexandria, Va.
In the study sponsored by the National Institute of Diabetes and Digestive and Kidney Diseases, half of the 1,441 patients in 29 clinical centers in the United States and Canada were given the current conventional treatment for Type I diabetes and were put on a nutrition and exercise program.
The other half, working closely with a team of nurses, dietitians and doctors, gave themselves blood tests four or more times a day by pricking their fingers. They then gave themselves three or four insulin injections or used a computer-operated insulin pump to automatically administer insulin into their abdomen, in order to keep their glucose levels as close to normal as possible.
The results were dramatic, researchers said: Diabetic eye disease (retinopathy), which is the leading cause of new cases of blindness, was reduced by about 50 percent. Diabetic nerve disease, a leading cause of foot ulcers and amputations in patients with Type I diabetes, was reduced by about 60 percent. Diabetic kidney disease, which can result in patients having to be on a kidney dialysis machine to stay alive, was prevented or delayed by about 50 percent.
The down-side of the study, researchers said, was that those in the intensive therapy group suffered three times more often from hypoglycemia, or too-low blood sugar, and had a tendency to gain weight.
The increased risk of hypoglycemia, which can cause fainting, convulsions or coma, resulted from the difficulty of trying to mimic a normal body's balanced and controlled insulin production. This is not a problem for most patients, who, when they get the symptoms of hypoglycemia _ dizziness, sweatiness, jitters _ can eat something to raise their blood sugar.
The benefits of intensive therapy "are fairly dramatic compared to the risks," said Dr. Robert Campbell of New York Hospital-Cornell Medical Center.
Key diabetes findings
Compared to people with diabetes following a standard regimen for controlling blood sugar, those performing more intensive control in the study showed reductions of approximately:
70 percent in progression of detectable diabetic retinopathy, an eye disease that can lead to blindness.
50 percent in retinopathy becoming bad enough to be referred for treatment.
50 percent in rates of treatment for sight-threatening retinopathy.
50 percent in rates of significant kidney damage, called diabetic nephropathy.
60 percent in rates of significant nerve damage, called neuropathy.