Sight Savers

Diabetic retinopathy is a leading cause of blindness. The right treatment, started early, can preserve vision

- By Liz Szabo

STERLING GLASS had many health problems as a child—swollen feet, night sweats, nausea and vomiting, unquenchable thirst, and fatigue that often left him too exhausted to go to school. The problems didn’t seem connected. Neither Glass nor his parents asked a doctor whether there was an underlying cause until he was 19, when he couldn’t get out of bed and wasn’t able to eat for five days because he felt so sick. That’s when doctors told the family that Glass had type 1 diabetes.

By that point, 30 years ago, Glass’s blood glucose levels had spiked to 600 milligrams per deciliter—six times higher than normal. “The doctor was blown away,” says Glass, who now is 49 and lives in Asheboro, N.C. “He was like, ‘I don’t know how you’re still alive. There’s no telling how long your sugar has been running that high.’”

Today Glass is blind. Years of uncontrolled blood glucose can cause serious damage to organs throughout the body. The eyes are frequent sites of injury. In the retina, the light-detecting tissue in the eye, excess glucose can harm tiny blood vessels and make them leak. The damage cuts off sight. Over time more than half of people with diabetes develop diabetic retinopathy, which can lead to vision loss and blindness. The condition affects nearly 10 million people in the U.S. and 100 million around the world. It is the leading cause of blindness in working-age people.