The JDRF-supported Joslin 50-Year Medalist Study has shown that more than 40 percent of people who have had type 1 diabetes (T1D) for at least 50 years have no or mild diabetic retinopathy, or eye disease, suggesting that many of the Medalists are somehow protected from this common complication of diabetes. New research findings reveal that the protected Medalists exhibit slow onset and/or progression of eye disease rather than regression (or reversal) of more serious forms of retinopathy.
Diabetic retinopathy occurs when high blood-glucose levels damage blood vessels in the eye. Eighty-six percent of people who have lived with T1D for at least 20 years will experience some degree of diabetic retinopathy, the leading cause of blindness in working-age (20-74 years) adults in the United States and other developed countries worldwide. A handful of treatments are available to halt progression of late-stage retinopathy and stop further vision loss, but these treatments do not cure retinopathy. No therapies are currently known to prevent the onset of diabetic retinopathy.
The Joslin Diabetes Center in Boston created the 50-Year Medalist Program to honor people who have lived with T1D for 50 years or more for their achievements in diabetes self-management. About 85 percent of people who receive 50-Year Medals subsequently agree to participate in the Medalist Study, a clinical research study aimed at identifying the genetic, environmental, psychological, and physiological factors that contribute to long-term survival in individuals with T1D. As a group, the Medalists have lower than expected rates of all major diabetes complications of T1D, including kidney disease and nerve damage in addition to retinopathy.
George King, M.D., the lead investigator on the Medalist Study, and his colleagues reported their latest findings on retinopathy in the Medalists at the American Diabetes Association’s 72nd Scientific Sessions in Philadelphia in June 2012. The study team wanted to understand whether the Medalists who seemed to be protected from the most advanced forms of retinopathy had slow progression of eye disease or if they had developed advanced retinopathy at some point that regressed over time to a milder form of the disease. This distinction could point the way to new treatments for preventing, slowing, or even reversing diabetic retinopathy.
The researchers reviewed the medical charts of 158 Medalists who had received repeated eye exams at Joslin over the course of 16 years on average. In Medalists who did not develop advanced retinopathy, researchers observed a slower rate of progression than in those who did develop the most serious form of the disease. No evidence of substantial regression was observed in Medalists who had intermediate levels of retinopathy. Of interest, once a Medalist had reached 20 years of T1D duration, he or she rarely experienced further progression of eye disease.
In future studies, Dr. King and the Medalist Study team are keen to identify the factors that halt or slow progression of diabetic retinopathy and confer protection from advanced eye disease in some people with longstanding T1D.
The Joslin 50-Year Medalist Study is an important component in the JDRF portfolio of research to prevent or treat complications of T1D. According to Helen Nickerson, Ph.D., JDRF senior scientific program manager of complications therapies, “The Medalists have survived so long with type 1 diabetes and some of them have very few complications, so we know they have something to teach us. Some of that might be lifestyle, but the reason that JDRF supported the Medalist Study is to consider whether there are biological or genetic factors that might account for their long duration of diabetes with few complications. Joslin’s efforts to characterize diabetic retinopathy in the Medalists are an important starting point for preventing or treating this complication in order to protect other people with type 1 diabetes from vision loss or blindness.”