However, it usually takes several years for diabetic retinopathy to reach a stage where it could threaten your sight.
To minimise the risk of this happening, people with diabetes should:
The retina is the light-sensitive layer of cells at the back of the eye that converts light into electrical signals. The signals are sent to the brain which turns them into the images you see.
The retina needs a constant supply of blood, which it receives through a network of tiny blood vessels. Over time, a persistently high blood sugar level can damage these blood vessels in 3 main stages:
However, if a problem with your eyes is picked up early, lifestyle changes and/or treatment can stop it getting worse.
Read about the stages of diabetic retinopathy.
You're at a greater risk if you:
By keeping your blood sugar, blood pressure and cholesterol levels under control, you can reduce your chances of developing diabetic retinopathy.
You won't usually notice diabetic retinopathy in the early stages, as it doesn't tend to have any obvious symptoms until it's more advanced.
However, early signs of the condition can be picked up by taking photographs of the eyes during diabetic eye screening.
Contact your GP or diabetes care team immediately if you experience:
These symptoms don't necessarily mean you have diabetic retinopathy, but it's important to get them checked out. Don't wait until your next screening appointment.
Everyone with diabetes who is 12 years old or over is invited for eye screening once a year.
Screening is offered because:
The screening test involves examining the back of the eyes and taking photographs. Depending on your result, you may be advised to return for another appointment a year later, attend more regular appointments, or discuss treatment options with a specialist.
Read more about diabetic eye screening.
You can reduce your risk of developing diabetic retinopathy, or help prevent it getting worse, by:
Read more about how to prevent diabetic retinopathy.
Treatment for diabetic retinopathy is only necessary if screening detects significant problems that mean your vision is at risk.
If the condition hasn't reached this stage, the above advice on managing your diabetes is recommended.
The main treatments for more advanced diabetic retinopathy are:
Read more about the treatment of diabetic retinopathy.