Why do many diabetics suffer from vision degeneration, but a few longtime diabetics escape it entirely?

The University of New Mexico’s Department of Ophthalmology & Visual Sciences confirmed plans to continue its five-year Diabetic Retinopathy Genomics (DRGen) study into just that.

“It is well known that the severity of diabetic retinopathy increases as somebody’s diabetes worsens,” Arup Das, MD said in a press release. “Here, as well as in Boston, we found a very small number of patients, who despite longer duration of diabetes – maybe 20 years or 30 years – have no eye disease. What is protecting them, whereas thousands and thousands of people are getting blindness in the eye?”

The five-year study led by Das, a distinguished and regents' professor at the University of New Mexico, has now marked its fourth year seeking hidden genetic factors that contribute to the course of diabetic retinopathy. The disease is considered a leading cause of blindness, according to the press release. 

Funded by the National Eye Institute, the initiative, performed in collaboration with Boston-based Harvard Medical School affiliate the Joslin Diabetes Center, cost $2.8 million, the UNM site states.

To conduct the study, the researchers collected blood samples from 450 UNM patients of mostly Hispanic and American Indian descent among New Mexico residents, while the samples collected in Boston were mostly from Caucasian patients. “We are in the process of analyzing the results,” Das says.

Another section of the study is analyzing diabetes patients, while others take notes on the overgrowth of new blood vessels, which leads to internal bleeding in the eye and ultimately vision loss, diabetic macular edema, and first-line treatment using anti-VEGF (eye injection) medications, the release notes. Different vision-loss factors appear to be more prevalent in different ethnic groups, it says.