Saving Your Sight from Blinding Diabetic Retinopathy
Diabetic eye disease robs sight from millions. But there are often ways to save vision
This article is part of “Innovations In: Type 1 Diabetes”, an editorially independent special report that was produced with financial support from Vertex.
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.’”
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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.
There are treatments to stave off the consequences. Surgery with scalpels or finely tuned lasers can stabilize the eye and preserve vision; in particular, new refinements in laser surgery can stop many abnormal blood vessels from growing. There are also drugs that inhibit vessel growth that can be injected directly into the eye; in the newest improvement, medical researchers have developed a small reservoir for these drugs that can be implanted directly into the eye, eliminating the need for repeated injections. And new research indicates that GLP-1 receptor agonists such as Ozempic and Mounjaro—which have gained staggering popularity because of their weight-loss effects—can slow or prevent retinopathy’s blinding deterioration because of the way they improve control over blood glucose.
Like many people with diabetic retinopathy, Glass says he had no vision problems before his diagnosis. An optometrist had told him he had 20/20 vision. But through his 30s, he had trouble controlling his glucose levels. He worked in a warehouse, sometimes driving a forklift, and he says the company didn’t allow him to bring blood glucose testing kits with needles to work, even during 12-hour shifts. On busy days Glass sometimes skipped lunch, which exaggerated the swings in his blood glucose levels.
When the doctor told Glass he had diabetic retinopathy, he thought to himself, “I have perfect vision. You are crazy. No way, no how, you’re not touching my eyes. I’m not having surgery, because there’s nothing wrong with me.”
Like Glass, who is Black, many people from historically marginalized communities have advanced disease by the time they’re diagnosed, partly because of a lack of access to health care. “It’s not easy in our health-care system to find a provider and get diagnosed early,” says Adrian Au, an ophthalmologist at the University of California, Los Angeles, Stein Eye Institute.
Although retinopathy is the most common cause of vision loss for people with diabetes, people with diabetes are at risk of other forms of eye disease as well. People with diabetes are two to five times more likely to develop cataracts, which cloud the lens of the eye. The macula, part of the retina needed for sharp vision, may become distorted, causing blurry sight.
Eventually Glass did agree to have surgery. The operation appeared to be successful at first, but his retinopathy had weakened many parts of his eyes. The retina in his left eye ultimately failed. “I never saw out of my left eye again,” he says.
Retina specialists tried multiple procedures to save his remaining vision, including injections of a medication directly into his right eye. This and similar medications slow or halt the growth of new blood vessels, and Maturi says they have revolutionized retinopathy treatment and prognosis. The medications block the action of a protein called vascular endothelial growth factor, or VEGF, that promotes blood vessel growth, including the development of abnormal blood vessels in the retina that threaten a person’s sight. Some newer drugs block additional proteins that contribute to diabetic retinopathy.
Anti-VEGF medications can slow the rate of vision loss and even reverse it, helping people see more clearly, Maturi says. Today these drugs are often the first treatment people receive. They “changed our field overnight,” Deobhakta says. “Anti-VEGF drugs became the standard of care.” The medications don’t work for everyone, however. They are less successful in patients with very advanced disease, and insurance coverage can restrict which drugs people are able to receive.
Sterling Glass talks to as many people as possible about managing their diabetes and protecting their eyesight: “Take it seriously. You get only one set of eyes.”
In the most common type of surgery, doctors aim to stabilize abnormal parts of the retina that can cause bleeding, swelling or detachment. They use lasers to scar the periphery of the retina—the outer region of the retina that’s responsible for side and night vision—to prevent it from sending growth signals that would lead to more abnormal blood vessels, Deobhakta says.
Scarring the outer retina can cause people to lose their peripheral vision, color vision and night vision. But by tamping down growth signals, the procedure can protect the macula, which is in the central retina. “It almost feels like you’re destroying the retina to save it,” Deobhakta says. “That’s kind of what it is.”
For Glass, his vision continued to worsen. He was still able to go out because his adult godson, who lived with him and his wife, served as a second pair of eyes. “He never left my side,” Glass says. Then a family rift prompted his godson to move out of the house. Glass thought he would be stuck at home, without any independence. He sank into a deep depression and even tried to kill himself.
His sister saved him. “My sister called me and said, ‘You’re not going to do this. You’re not gonna die. And you’re not gonna give up. You’re gonna live,’” Glass recalls. And she had a plan for how he was going to live. She is a professional singer, and she helped him contact the music director of the Blind Boys of Alabama, a Grammy-winning gospel group made up of Black men who have lost their sight. They invited him to audition.
“I met the five gentlemen who would change my life, although I didn’t know that at the time,” Glass says. It was the first time that he had met other blind people. He says he was amazed to meet men who had persevered and succeeded in spite of the loss of their vision. The men shared their stories and suggested organizations that Glass could call for help. It was the closest thing to a support group that he had experienced since losing his sight.
“After returning back home, I thought to myself, ‘Whether I go out with these guys to sing or whether they don’t even call me back after today, I’m happy. For these gentlemen to be able to live and be blind, I felt like, ‘Okay, now I have hope. I don’t have to die. I can still live.’”
A few weeks later the Blind Boys invited Glass to join the band. He sang with them for the first time in 2022 and has been performing ever since. He is, he says, glad to be alive.
Newer forms of treatment may provide more help for people with diabetic retinopathy. Early versions of the injectable medications had to be put into the eyes once every month, and the frequent medical visits created a burden for people trying to hold down a job or take care of their family. Many patients are “working-class people who often may not even have insurance,” Deobhakta says. “So you often get more and more complications because patients can’t get their injections.”
But the latest generation of anti-VEGF injections can last for two or even three months, requiring fewer doctor visits, Deobhakta says. And now there’s a refillable reservoir for the drugs that can be implanted in the eye. The device only needs to be refilled every nine months.
People with type 1 diabetes may also get aid from the new glucagonlike peptide 1 (GLP-1) receptor agonist drugs, such as Ozempic. The barrage of media coverage highlights their weight-loss functions, but formulations of these drugs were originally developed to help people with diabetes control their blood sugar. Glass takes a GLP-1 drug called Mounjaro, along with short- and long-acting insulin and other drugs that help to control diabetes.
Recent research has produced conflicting results about the ways that GLP-1 drugs might affect the progression of early diabetic eye disease. Some studies link them to a small—and temporary—increase in early diabetic retinopathy, leading experts to suggest that people who take the drugs should receive regular eye exams. On the positive side, research also finds that people who take GLP-1 drugs have a lower risk of progressing to worse stages of diabetic retinopathy and blindness. Because any increase in retinopathy appears to be short-lived, stabilizing with vision still intact after a period of time, the benefits of GLP-1 drugs outweigh the risks, Sodhi says. “In general, it’s better to get good control of your blood sugar” with these medications, he notes.
Scientists are also exploring gene therapy—implanting a gene that helps to inhibit blood vessel growth—in the hope of treating retinopathy with a one-time eye treatment. And research hints that a drug class called fenofibrates, which has been used to treat abnormal levels of cholesterol and triglycerides in the blood, can reduce the risk that early diabetic retinopathy will become more severe.
Glass says he now works hard to manage his diabetes. He and another member of the Blind Boys, who also has diabetes, encourage each other to check their blood glucose. While traveling with the group, which performs at least 100 shows a year, Glass says he talks to as many people as possible about the importance of managing diabetes and protecting their eyesight. “If I could tell anybody anything, I would say, ‘Take it seriously.’ You get only one set of eyes.”
According to the National Eye Institute, early detection, treatment and follow-up exams for diabetic retinopathy can reduce the risk of blindness by 95 percent. The American Diabetes Association recommends people with type 1 diabetes have their first eye exam within five years of diagnosis. Au notes that identifying people with diabetic retinopathy and referring them for additional services before they lose their vision can help them be more prepared if their eyesight deteriorates. At his eye institute, doctors can help people access visual rehabilitation, which can provide technology such as magnifiers and screen readers; counseling and emotional support programs; and transportation and household services.
Overall there is a shortage of doctors who specialize in treating the retina, and some health systems are trying to compensate for this by using telemedicine and artificial intelligence to screen people with diabetes for retinopathy, a development that could be especially helpful for those who live in rural areas. Primary care providers can take photographs of the retina, which can be reviewed by an AI program. Doctors can then refer people to retinal specialists for future evaluation and treatment.
As for Glass, he says the Blind Boys have not just given him a career. They have given him purpose. “I’ve got a new mission,” he asserts. “I have an opportunity not only to live but to share my story with people. I am very passionate about saving anybody that I can.”
IF YOU NEED HELP
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Liz Szabo is a veteran health and science journalist who has worked at USA TODAY and other newsrooms.
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