Diabetic Retinopathy

Causes and Risk Factors

Who Is at Risk?

All people with diabetes -- both type 1 and type 2 -- are at risk for diabetic retinopathy. People with diabetes are also at increased risk for cataract and glaucoma. That's why everyone with diabetes should get a comprehensive dilated eye exam at least once a year.

Between 40 to 45 percent of Americans diagnosed with diabetes have some stage of diabetic retinopathy. If you have diabetic retinopathy, your doctor can recommend treatment to help prevent its progression.

How Vision Loss Occurs

Blood vessels damaged from diabetic retinopathy can cause vision loss in two ways.

  1. Fragile, abnormal blood vessels can develop and leak blood into the center of the eye, blurring vision. This is proliferative retinopathy and is the fourth and most advanced stage of the disease.
  2. Fluid can leak into the center of the macula, the part of the eye where sharp, straight-ahead vision occurs. The fluid makes the macula swell, blurring vision. This condition is called macular edema.

Macular edema can occur at any stage of diabetic retinopathy, although it is more likely to occur as the disease progresses. About half of the people with proliferative retinopathy also have macular edema.

Have Dilated Eye Exams

The National Eye Institute (NEI) urges everyone with diabetes to have a comprehensive dilated eye exam at least once a year. If you have diabetic retinopathy, you may need an eye exam more often. People with proliferative retinopathy can reduce their risk of blindness by 95 percent with timely treatment and appropriate follow-up care.