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 diseases 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 type 1 diabetes 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.
When television's perennially popular Mary Richards walked into WJM's Minneapolis newsroom in 1970, she did more than show the world a single girl could "make it on her own." The award-winning actress who portrayed her -- Mary Tyler Moore -- also showed us diabetes and a career could coexist.
Moore was diagnosed with adult-onset type 1 diabetes in the 1960s, several years before her Emmy-winning show began. But that didn't stop Moore from pursuing her career or turning the world on with a smile...
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 blindness in adults under age 65.
How Did Intensive Treatment Affect Diabetic Kidney Disease?
Participants in the DCCT were tested to assess the development of diabetic kidney disease (nephropathy). Findings showed that intensive treatment prevented the development and slowed the progression of diabetic kidney disease by 50 percent.
Diabetic kidney disease is the most common cause of kidney failure in the United States and the greatest threat to life in adults with type 1 diabetes. After having diabetes for 15 years, one-third of people with type 1 diabetes develop kidney disease. Diabetes damages the small blood vessels in the kidneys, impairing their ability to filter impurities from blood for excretion in the urine. Persons with kidney damage must have a kidney transplant or rely on dialysis to cleanse their blood.