What causes diabetic retinopathy?

Jeffrey S. Heier, MD
Ophthalmology
Diabetic retinopathy occurs when abnormal blood sugar levels damage small blood vessels in the retina (the innermost layer of the eye). Ongoing high blood sugar levels that result from poorly managed diabetes can cause the tiny blood vessels in the retina to break down and leak fluid into surrounding tissues, leaving deposits of protein and fat called hard exudates. The vessel walls can also develop tiny bulges called microaneurysms. Eventually, the damage blocks the retina's blood supply. Nerve fibers die, creating white fluffy patches known as cotton-wool spots.
Diabetic retinopathy, the leading cause of blindness in American adults, is caused by damage to the eyes' blood vessels. High blood sugar levels and high blood pressure associated with diabetes can cause the tiny blood vessels of the eyes to swell, weaken and leak fluid, which can lead to blurry or double vision and ultimately to partial or total blindness. In some people, abnormal blood vessels grow on the surface of the retina. Notify your doctor at the first sign of any vision problems and have eye exams yearly to minimize your own risks of diabetic retinopathy.
Johns Hopkins Medicine
Administration
The longer you live with diabetes, the more likely you are to develop diabetic retinopathy. Nearly all individuals with type 1 diabetes - which generally strikes in childhood - develop some degree of retinopathy within 20 years of diabetes diagnosis, as do more than 60 percent of those with type 2 (adult onset) diabetes.
Other causes:
  • Poor blood glucose control is a significant risk factor for development and progression of diabetic retinopathy, but it is also relatively easy to control.
  • High blood pressure, high blood lipids, and pregnancy are other factors associated with development and progression of diabetic retinopathy.

Continue Learning about Diabetic Retinopathy (Eye Damage)

Important: This content reflects information from various individuals and organizations and may offer alternative or opposing points of view. It should not be used for medical advice, diagnosis or treatment. As always, you should consult with your healthcare provider about your specific health needs.