Understanding diabetic eye disease: types, risks and treatments

In people with diabetes, uncontrolled high blood sugar levels can lead to damage of the tiny blood vessels (the capillaries) in the retina, causing eye diseases such as diabetic retinopathy (DR) and diabetic macular edema (DME). Over time, this damage may lead to vision loss.3

Diabetic retinopathy (DR)

DR occurs when damage to blood vessels and the formation of new blood vessels causes blood and/or fluid to leak into the retina. This can lead to swelling and blockage of blood supply to some areas of the retina. As the condition progresses, vision can become impaired.3,4 

DR affects more than 100 million people globally, causing blindness in 830k people and visual impairment in 3.7 million.5,6

Diabetic macular edema (DME)

DME is a serious eye condition that can lead to vision loss and is a complication of DR.6 In many cases, it can be managed to prevent this outcome if detected and treated early. DME occurs when the damaged blood vessels leak into, and cause swelling in the macula.3 The macula is the central area of the retina responsible for the sharp vision needed for reading, driving and recognising faces.3,7

DME is a leading cause of vision loss among working-age adults, affecting approximately 21 million people globally.6 As the rate of diabetes grows, more and more people will be affected by DME,6,8 with an increase of 25% expected from 2020 to 2030.9

People with diabetic eye diseases face more than double the healthcare costs than those with diabetes alone.10

What are the signs and symptoms of diabetic eye diseases?

The most common signs and symptoms of DR and DME include:3,11,12 

Vision lost to DR can be irreversible, but early detection and treatment can reduce the risk of blindness by 95%.3,12 At first, it may cause no, or only mild, eyesight problems, so treatment is often delayed until complications occur, such as the development of DME.3,12

Are there risk factors for diabetic eye diseases?

There are a number of risk factors linked to the development of DR and DME, including:11,13,14

How is DME diagnosed?

To diagnose DME, an eye doctor can carry out a comprehensive eye examination using a number of tests. These may include a vision test to determine the smallest letters that can be read on a standardised chart; a dilated eye examination, in which drops are placed in the eyes to widen the pupils; imaging tests such as optical coherence tomography (OCT) or fluorescein angiography (FA); and tonometry, a test that measures the pressure inside the eye.15

Current treatment options for diabetic eye disease

In many cases, DME and DR can be managed and vision loss can be prevented if they are detected and treated early.11,14,16

The most common treatment involves injections into the eye called VEGF inhibitors or dual VEGF/Ang-2 inhibitors.13,17,18 These treatments help prevent new, abnormal blood vessels from forming and reduce leakage from damaged vessels, which helps protect vision.13,17,18

In some situations, laser therapy may be offered, especially if the DME doesn’t affect the central part of the macula (the fovea). However, laser treatment usually stabilises vision rather than improves it and can sometimes cause side effects like scarring, which may create permanent blind spots.11,13,14 Because of these risks, laser therapy is now rarely used and has mostly been replaced by more advanced treatments.11,13,14

Annual eye tests are vital to keep on top of your eye health, particularly if you live with diabetes. If you notice any changes in your vision, report these to your eye doctor or visit:  https://retina-international.org/