Many people think about diabetes solely from a dietary perspective: They know that they have to keep their blood-sugar levels under control, so they focus on foods that they should or shouldn’t eat.
If they’re concerned about diabetes complications, people may worry about high blood pressure, kidney disease or even foot ulcers, but they may not consider their eye health, which can be a terrible mistake.
Vision is perhaps our most important sense, and people with diabetes are more likely to have visual impairments or lose their sight than healthy people. In the U.S., diabetes is a leading cause of blindness. Yet many people with diabetes don’t see an ophthalmologist annually for a dilated eye exam, which is the best way to check for diabetes-related problems. (Seeing an optometrist for glasses isn’t the same thing as going to an ophthalmologist.)
“Eye disease can come on without any warning,” said ophthalmologist Emily Chew, M.D., director of the division of epidemiology and clinical applications with the National Eye Institute, in a phone interview with HealthCentral. “They don’t realize that things can go bad when things are perfect [with their vision], or they’re not being referred out for an eye exam as often as they should be.”
Controlling your blood-sugar levels may help to minimize eye problems. Even so, experts recommend seeing an ophthalmologist as soon as you’re diagnosed with diabetes, then annually.
“We can see the changes from the eye disease much, much earlier than the patient can,” said Lloyd Paul Aiello, MD, Ph.D., director of the Beetham Eye Institute at Joslin Diabetes Center and professor of ophthalmology at Harvard Medical School, in a phone interview with HealthCentral. “These days, we can prevent more than 95 percent of blindness from diabetes if we find it at the right time – if we start treatments when they’re needed. But if a patient waits until they lose vision, then that’s really much later than we like to start.”
Ophthalmologists screen for and treat these eye conditions, which are more common among people with diabetes:
Diabetes affects small blood vessels throughout the body, including the area in the back of your eye known as the retina. If you have diabetic retinopathy, blood vessels in the retina may leak, causing the retina to swell, which can damage vision. Retinopathy may also cause faulty, leaky blood vessels to grow within the retina, which can harm vision. Or scarring from new blood vessels may pull on the retina and detach it from the back of your eye, causing vision loss.
All of these things may develop while your vision is intact, and damage can occur suddenly. The only way to get diagnosed is to see an ophthalmologist, which can control unwanted blood-vessel activity with medication and/or laser treatments.
“You can have no eye symptoms at all and have very serious disease,” Aiello said. “You want to treat it at the right time so you don’t lose vision. There’s much that we can do, but it’s not definite that we can bring the vision back.”
When the lens in your eye clouds over, you have a cataract. Many healthy people develop cataracts as a consequence of aging. People with diabetes – especially poorly controlled diabetes – have a higher rate of cataracts, and they get them at an earlier age.
“It’s like having a dirty window,” Aiello said. “You may not be able to see out of it.”
Some people aren’t bothered by their cataracts. Others experience vision problems. Cataract surgery is offered to patients with vision problems, to remove the cloudy lens and replace it was a new, clear one. It’s a very safe, common procedure, even for people with diabetes.
“Diabetics take a few days longer to heal fully than other patients – it’s just the nature of diabetes,” said Ravi Goel, M.D., clinical spokesperson for the American Academy of Ophthalmology, a New Jersey-based ophthalmologist, in a phone interview with HealthCentral. “Living a healthy lifestyle can hopefully slow the progression and the onset, to begin with.”
When you have glaucoma, too much fluid builds up in your eye, which can increase your eye pressure and damage your optic nerve, causing vision loss. Although anyone may develop glaucoma, it may be twice as common among people with diabetes. Most forms of glaucoma have no symptoms, so visiting the ophthalmologist is critical.
“Glaucoma is another silent disease – it has silent symptoms and causes difficulties with peripheral vision, which may not be as easily recognizable for patients,” Goel said.
The most common types of glaucoma can be treated with prescription eyedrops, but a rare form, which most commonly affects people with diabetes, is caused by new blood vessels growing within the eye. That needs to be addressed with medication and/or laser treatments.