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:
- ensure they control their blood sugar levels, blood pressure and cholesterol
- attend diabetic eye screening appointments – annual screening is offered to all people with diabetes aged 12 and over to pick up and treat any problems early on
How diabetes can affect the eyes
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:
- background retinopathy – tiny bulges develop in the blood vessels, which may bleed slightly but don't usually affect your vision
- pre-proliferative retinopathy – more severe and widespread changes affect the blood vessels, including more significant bleeding into the eye
- proliferative retinopathy – scar tissue and new blood vessels, which are weak and bleed easily, develop on the retina, this can result in some loss of vision
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.
Am I at risk of diabetic retinopathy?
You're at a greater risk if you:
- have had diabetes for a long time
- have a persistently high blood sugar (blood glucose) level
- have high blood pressure
- have high cholesterol
- are pregnant
- are of Asian or Afro-Caribbean background
By keeping your blood sugar, blood pressure and cholesterol levels under control, you can reduce your chances of developing diabetic retinopathy.
Symptoms of 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:
- gradually worsening vision
- sudden vision loss
- shapes floating in your field of vision (floaters)
- blurred or patchy vision
- eye pain or redness
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.
Diabetic eye screening
Everyone with diabetes who is 12 years old or over is invited for eye screening once a year.
Screening is offered because:
- diabetic retinopathy doesn't tend to cause any symptoms in the early stages
- the condition can cause permanent blindness if not diagnosed and treated promptly
- screening can detect problems in your eyes before they start to affect your vision
- if problems are caught early, treatment can help prevent or reduce vision loss
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.
Reduce your risk of diabetic retinopathy
You can reduce your risk of developing diabetic retinopathy, or help prevent it getting worse, by:
- controlling your blood sugar, blood pressure and cholesterol levels
- taking your diabetes medication as prescribed
- attending all your screening appointments
- getting medical advice quickly if you notice any changes to your vision
- maintaining a healthy weight, eating a healthy, balanced diet, exercising regularly and stopping smoking
Read more about how to prevent diabetic retinopathy.
Treatments for 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:
- laser treatment
- injections of medication into your eyes
- an operation to remove blood or scar tissue from your eyes
Read more about the treatment of diabetic retinopathy.