The DCCT is a clinical study conducted from 1983 to 1993 by the National Institute of
Diabetes and Digestive and Kidney Diseases (NIDDK). the study showed that keeping
blood sugar levels as close to normal as possible slows the onset and progression of eye,
kidney, and nerve disease caused by diabetes. In fact, it demonstrated that any sustained
lowering of blood sugar helps, even if the person has a history of poor control.
the largest, most comprehensive diabetes study ever conducted, the DCCT involved 1,441
volunteers with insulin-dependent diabetes mellitus (IDDM) and 29 medical centers in the
United States and Canada. Volunteers had diabetes for at least 1 year but no longer than 15
years. They also were required to have no, or only early signs of, diabetic eye disease.
The study compared the effects to two treatment regimens-standard therapy and intensive
control-on the complications of diabetes. Volunteers were randomly assigned to each
treatment group.
| How Did Intensive Treatment Affect Diabetic Eye Disease? |
All DCCT participants were monitored for diabetic retinopathy, an eye disease that affects
the retina. Study results showed that intensive therapy reduced the risk for developing
retinopathy by 76 percent. In participants with some eye damage at the beginning of the
study, intensive management slowed the progression of the disease by 54 percent.
The retina is the light-sensing tissue at the back of the eye. According to the National Eye
Institute, one of the National Institutes of Health, as many as 24,000 persons with diabetes
lose their sight each year. In the United States, diabetic retinopathy is the leading cause of
blinding in adults under age 65.
