Diabetic retinopathy

Diabetic retinopathy is a complication of diabetes, caused by high blood sugar levels damaging the back of the eye (retina). It can cause blindness if left undiagnosed and untreated. Everyone with diabetes who is 12 years old or over is invited for eye screening once a year.

About diabetic retinopathy 

Diabetes is a lifelong condition that causes a person's blood sugar level to become too high.

It usually takes several years for diabetic retinopathy to reach a stage where it could threaten your sight.

To reduce the risk of this happening, people with diabetes should:

  • ensure good control of 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. It converts light into electrical signals. The signals are sent to the brain. The brain turns them into the images you see.

The retina needs a constant supply of blood. It receives this supply through a network of tiny blood vessels. Over time, a persistently high blood sugar level can damage these blood vessels in three main stages:

  • tiny bulges develop in the blood vessels, which may bleed slightly but don’t usually affect your vision
  • more severe and widespread changes affect the blood vessels, including more significant bleeding into the eye 
  • scar tissue and new blood vessels, which are weak and bleed easily, develop on the retina – it can result in some loss of vision

If a problem with your eyes is picked up early, lifestyle changes and/or treatment can stop it getting worse.

People most at risk of diabetic retinopathy

Anyone with type 1 diabetes or type 2 diabetes is potentially at risk of developing diabetic retinopathy.

You're at a greater risk if you:

By keeping good control of your blood sugar, blood pressure and cholesterol levels, you can reduce your chances of developing diabetic retinopathy.

Symptoms of diabetic retinopathy 

You won't usually notice diabetic retinopathy in the early stages. This is because it doesn't tend to have any obvious symptoms until it's more advanced.

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
  • discuss treatment options with a specialist


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

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 information on this page has been adapted from original content from the NHS website.

For further information see terms and conditions.

This page was published November 2017

This page is due for review March 2019

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