Scientists focus on global impact of diabetic retinopathy

Fort Lauderdale, FL-The incidence of diabetes, which had been increasing by leaps and bounds along with complications of the disease such as diabetic retinopathy (DR), now has been showing signs of stabilizing and decreasing as the result of intensive management of the disease in the United States and developing countries.

Ronald Klein, MD, MPH, discussed the epidemiology of diabetes, the changes in risk-factor profiles, and management practices regarding the projections of the prevalence of DR and impairment of vision in patients with diabetes at the annual meeting of the Association for Research in Vision and Ophthalmology.

Alarming projections

"It is expected that there will be significant increases in developed and developing countries of two to three times," he said. "This is largely due to high rates of obesity and changes in the levels of physical activity and diet over the last 50 years. These developments have significant implications for diabetic eye disease."

The actual numbers in terms of human disease were staggering when considering that in India in 2000, an estimated 32 million people had diabetes, Dr. Klein said. That number was projected to reach 79 million in 2030, he added.

A study conducted in southern India reported that if the prevalence of complications of diabetes remained the same, the number of individuals who have any degree of DR, which was 6 million in 2000, will increase to 14 million by 2030, the 0.3 million people estimated to have proliferative DR will jump to 0.7 million by 2030, and 7 million people with clinically relevant macular edema (ME) will increase by 1.8 million by 2030, Dr. Klein said.

"There is an implicit assumption that such projections of the future prevalence of proliferative DR and ME, their risk factor profiles, and life expectancies of persons with type 2 diabetes will remain the same," he added.

The Wisconsin Epidemiological Study of Diabetes Retinopathy (WESDR) also projected marked increases in DR based on data collected from 1990 to 1992, he said. According to the study, of the 5.8 million Americans with diabetes, approximately 16% would go on to develop proliferative disease, and about 10% would develop clinically relevant ME, according to Dr. Klein.

In 2004, when data from the WESDR study were added to data collected from other population-based studies, the estimates also pointed to marked increases in vision-threatening disease, he said. "The prevalence of visually threatening DR, clinically significant DR, and proliferative disease in persons 40 years and older will increase from 680,000 people to 1.6 million in the United States by 2020," Dr. Klein said.