Diabetic retinopathy: symptoms, screening and treatment

The NHS says diabetic retinopathy does not usually have any symptoms at first, and is usually found at diabetic eye screening. In the later stages, symptoms can include your eyesight getting worse, blurred vision, dots and lines (floaters) in your vision and finding it harder to see in the dark or low light.

Symptoms may gradually get worse over time and can affect one or both eyes. They do not always mean you have diabetic retinopathy, but they are important to get checked.

Diabetic retinopathy happens when high blood glucose (sugar) damages the blood vessels in the retina, the light-sensitive layer at the back of the eye. The NHS says it is more likely if you have had diabetes for a long time, and if you have high blood pressure or high cholesterol.

It usually gets worse gradually, over several years, and treatment can help stop it progressing to the next stage.

The NHS describes three stages. There is also a separate type called diabetic maculopathy, which in the early stages has no symptoms and does not affect your vision. In a very small number of people it progresses to an advanced stage and affects the central part of vision, so you may see around the edges but not be able to read clearly.

The NHS says if you have diabetes and are aged 12 or over you will get a letter every 1 or 2 years inviting you for diabetic eye screening. People with gestational diabetes are not invited. You are usually invited when diagnosed, then every year, or every 2 years if your last 2 tests found no changes.

The appointment lasts around 30 minutes. You read letters on a chart, eye drops enlarge your pupils (they may sting and blur your sight), and photographs are taken of the back of your eyes. Your sight may be blurry for a few hours, so you cannot drive afterwards; plan how you will get home.

You will get a letter with the result, usually within 3 weeks. If you have not had an invitation, contact your GP practice or local eye screening service. Screening is your choice, but it is an important part of diabetes care and is not the same as a regular optician eye test.

The NHS says it is not possible to cure sight loss caused by diabetic retinopathy; the aim of treatment is to help stop vision getting worse. Managing your diabetes well is important. If you have background or pre-proliferative diabetic retinopathy you do not need treatment and are monitored at your screening appointments. Proliferative disease means referral to an eye specialist.

• Laser treatment on the blood vessels at the back of the eye (laser photocoagulation).

• Regular eye injections of a medicine called anti-VEGF, which reduces damage to blood vessels.

• An eye implant that gradually releases steroid medicine to reduce swelling.

• Eye surgery, such as an operation to remove scar tissue or blood from the back of the eye.

The NHS says if you have diabetes you can reduce the risk of diabetic retinopathy by managing your blood glucose as well as possible, for example by attending a diabetes course, making healthy lifestyle changes to lower high blood pressure and high cholesterol, and not smoking.

Go to all of your diabetic eye screening appointments, because they help find and treat problems as soon as possible. You also need regular opticians’ eye tests to check for other eye problems linked to diabetes, such as glaucoma.

Contact a GP, your diabetes care team or an optician if you have diabetes and problems with your eyes or vision, such as your eyesight getting worse over time, floaters or difficulty seeing in low light.

Ask for an urgent GP appointment or get help from NHS 111 if you have diabetes and your eyesight suddenly gets worse or you get blurred vision.

NHS diabetic eye screening is free for people with diabetes and is arranged by local screening services, with referral to hospital eye clinics when treatment is needed. Private eye clinics also offer retinal imaging and treatment; they do not replace the NHS screening invitation, so keep attending it and share any private results with your diabetes team.

If your vision is affected, support from your diabetes team, local groups and national charities such as Diabetes UK and the RNIB is described by the NHS as helpful.