Diabetic retinopathy is the most common form of diabetic eye disease. Diabetic retinopathy usually only affects people who have had diabetes (diagnosed or undiagnosed) for a significant number of years.

Retinopathy can affect all diabetics and becomes particularly dangerous, increasing the risk of blindness, if it is left untreated.

The risk of developing diabetic retinopathy is known to increase with age as well with less well controlled blood sugar and blood pressure level.

According to the NHS, 1,280 new cases of blindness caused by diabetic retinopathy are reported each year in England alone, while a further 4,200 people in the country are thought to be at risk of retinopathy-related vision loss.

All people with diabetes should have a dilated eye examination at least once every year to check for diabetic retinopathy.

What is diabetic retinopathy?

Diabetic retinopathy occurs when changes in blood glucose levels cause changes in retinal blood vessels. In some cases, these vessels will swell up (macular oedema) and leak fluid into the rear of the eye.

In other cases, abnormal blood vessels will grow on the surface of the retina.
Unless treated, diabetic retinopathy can gradually become more serious and progress from ‘background retinopathy’ to seriously affecting vision and can lead to blindness.

Diabetic retinopathy includes 3 different types:

• Background retinopathy
• Diabetic maculopathy
• Proliferative retinopathy

What are the symptoms of diabetic retinopathy?

Like many conditions of this nature, the early stages of diabetic retinopathy may occur without symptoms and without pain. An actual influence on the vision will not occur until the disease advances.

Macular oedema can result from maculopathy and affect vision occurs if leaking fluid causes the macular to swell. New vessels on the retina can prompt bleeding, which can also block vision in some cases.

Symptoms may only become noticeable once the disease advances, but the typical symptoms of retinopathy to look out for include:

• Sudden changes in vision / blurred vision
• Eye floaters and spots
• Double vision
• Eye pain

How is diabetic retinopathy caused?

Diabetic retinopathy is caused by prolonged high blood glucose levels. Over time, high sugar glucose levels can weaken and damage the small blood vessels within the retina.

This may cause haemorrhages, exudates and even swelling of the retina.

This then starves the retina of oxygen, and abnormal vessels may grow. Good blood glucose control helps to lower diabetes retinopathy risks.

Am I at risk from diabetic retinopathy?

Diabetic retinopathy risk factors include the following.

If any of the below affect you it’s worth having an retinopathy screening examination as quickly as possible.

• Poor blood glucose control
• Protein in urine
• High blood pressure
• Prolonged diabetes
• Raised fats (triglycerides) in the blood

Anyone suffering from diabetes faces the risk of developing diabetic retinopathy and other diabetes complications.

The longer a person has diabetes, the greater the risk of developing diabetic retinopathy becomes. However, keeping blood glucose levels well controlled can help to significantly slow down the development of retinopathy.

People with diabetes should, however, be aware that a rapid improvement in blood glucose levels can lead to a worsening of retinopathy. A rapid improvement in blood glucose levels in this case is defined as a drop in HbA1c of 30 mmol/mol or 3%.