Diabetic retinopathy gradually can lead to blindness, but the progression can be slowed and often halted with effective diabetes management and frequent eye exams.

Story by: Norton Healthcare; Reviewed by Lisal J. Folsom, M.D., M.S.; Stacy L. Koch, APRN on July 7, 2023

Diabetic retinopathy (DR) is caused by damage to the small blood vessels in the retina, located in the back of the eye. High blood sugar over time increases the risk of diabetic retinopathy. There are several stages of DR, and higher stages  eventually can lead to blindness. The good news is that the progression can be slowed and often halted with effective diabetes management and frequent eye exams to catch any damage early.

Along with macular edema, cataracts and glaucoma, diabetic retinopathy is among the main vision risks for those with diabetes, including Type 1, Type 2 and gestational diabetes.

In the early stage, called mild nonproliferative diabetic retinopathy, blood vessels in the retina begin to bulge. The change is too small for you to notice, but your eye doctor will be able to see the change.

“There are typically no noticeable symptoms at the early stages of diabetic retinopathy, which is why it’s so important to get your eyes examined at least once a year,” said Stacy L. Koch, APRN, nurse practitioner with Norton Community Medical Associates – Endocrinology.

Treatment during the early stages of diabetic retinopathy helps to repair damage and can prevent blindness, according to Stacy. Frequent vision screenings allow early treatment before damage affects your sight.

Diabetic retinopathy often affects both eyes at the same time.

As the disease progresses, fluid, including blood, leaking into the space between the lens at the front of your eye and the retina at the back significantly can impair your vision.

Swelling in the retina — macular edema — drastically can distort your vision and cause blindness. The macula is a spot on the retina that allows you to see detail and what is directly in front of you. About one-third of those with diabetic retinopathy develop macular edema.

As blood vessels in the retina become blocked or stop working properly, the body sends signals for the eye to create more blood vessels. Growth of these new, fragile blood vessels marks the more severe, advanced stage of diabetic retinopathy called proliferative DR. These new blood vessels often bleed, leaking blood into the eye. People with this stage of DR may notice dark spots or complete blockage of vision.

Preventing the progression of nonproliferative diabetic retinopathy to this advanced stage is critical to saving your sight.

Advanced-stage diabetic retinopathy symptoms

• Blurry vision
• Floaters — spots or dark shapes in your vision
• Trouble seeing colors
• Dark or empty areas in your vision
• Vision loss

High blood sugar from diabetes, which damages blood vessels throughout your body, causes diabetic retinopathy. Damage to the blood vessels in the retina — the light-sensitive layer at the back of the eye — is one of the causes of vision complications of diabetes.