Diabetes affects more and more people in the UK every year - about three million today compared with 1.8 million less than a decade ago. About 90% of people with diabetes have type 2, which usually develops later in life than type 1 and can often be treated (at least in the early years) with diet and tablets rather than insulin.
In many respects type 1 and type 2 diabetes are very different conditions. Type 1 diabetes is an autoimmune disease not linked to lifestyle or weight, while type 2 diabetes is (almost) all about weight and lifestyle. But in terms of long-term complications there are many similarities. They're both diagnosed on the basis of raised blood glucose, and this raised glucose can cause similar complications in both - kidney problems; eye disease; and nerve damage which can lead to ulcers or even amputation of the foot. People with type 1 and type 2 diabetes are also at increased risk of heart attack .
On the plus side, improvements in medical treatments mean many more people with diabetes are surviving into old age. Fortunately, with some forward thinking, adjustments to your life and a little help from your friendly diabetes team, you can keep your eyes healthy for years to come.
Diabetes - why worry about your eyes?
High blood sugars over several years can weaken and damage the blood vessels at the back of the eye, which supply blood to the retina (the layer of cells that send messages about what you're seeing to your brain). This is known as diabetic retinopathy. It can result in leakage of fluid from the blood vessels, tiny bleeds, little bubbles of weakened vessel walls (called microaneurysms) and problems with the blood supply to the retina. New blood vessels grow to try to improve the blood supply, but these blood vessels are easily damaged and can harm your eyesight.
The macula is a small part near the middle of your field of sight that is tightly packed with light-sensitive cells. It allows you to see in fine detail. In severe diabetic retinopathy, fluid and scar tissue can build up on the macula, causing a condition called macular oedema. Diabetic macular oedema affects about 50,000 people in the UK - it's the commonest preventable cause of blindness in adults of working age.
What treatments are available?
Eye screening is key because it picks up progressive changes in your eyes which can be treated before they cause catastrophic damage. If you develop early retinopathy, you'll be encouraged to keep working on your blood glucose control and your eyes will be monitored more regularly. Later, laser surgery (done under local anaesthetic as a day patient) can prevent problems progressing, although it can't restore vision you've lost.
In the past, there was little or no treatment for diabetic retinopathy or macular oedema, other than using tight glucose control to try to stop it worsening. That's still important today, but now we have two main options for treatment, depending on how bad your symptoms are. The first is laser surgery to seal off the abnormal new blood vessels growing on the back of the eye.
The second is the injection of vascular endothelial growth factor (VEGF) inhibitor medicines - Lucentis® is licensed for treatment of diabetic macular oedema, and now the National Institute for Health and Care Excellence (NICE) has approved a new drug for some people. Eylea® has already been approved by NICE for another condition affecting the macula, called age-related macular degeneration but this new approval increases the options available for people whose eyesight is threatened by diabetic macular oedema.
Prevention is better than cure
But these treatments are only needed if the condition develops in the first place, and prevention is always better than cure. In both type 1 and type 2 diabetes, a healthy diet, regular exercise and tight control of your blood pressure, cholesterol and blood sugar can all help cut your risk of complications. By keeping your blood sugar well controlled, you can hugely reduce the risk of damage to your eyes. You're likely to need to take tablets (unless you have type 1 diabetes, in which case you'll definitely need to take insulin for your blood sugar) to help with all of these, but lifestyle changes play a major part. Stopping smoking will also protect you from complications.
Screening for health!
Everyone needs regular eye checks, but in diabetes you should also be having a check called diabetic retinopathy screening, which involves using drops to dilate your pupils so details photos can be taken of your retina.
We're incredibly lucky in this country - the NHS Diabetic Eye Screening Programme is the envy of the world. Virtually no other country has a system for annual eye screening for everyone with diabetes over 12 years old - once a year, you'll be offered a 30-minute appointment which involves dilating your pupils with drops and taking photographs of the retina at the back of your eye. This checks for diabetic retinopathy and if early signs and symptoms are found, you'll either be called back for follow-up sooner or referred on to a specialist with a view to assessing you for treatment.
Both diabetic retinopathy and macula oedema get more likely with increasing length of diabetes - few people have any diabetic retinopathy if they've had diabetes for under five years, but up to one in person in three who has had diabetes for 25 to 30 years will have some degree of macular oedema. If you have diabetes, you're also more likely to get cataracts (clouding of the lens) and glaucoma (raised pressure inside the eyeball) - both treatable as long as you have regular eye checks and take treatment as advised
By taking preventive steps and getting regular eye checks from an early stage, you could just avoid becoming a statistic. If you don't get invited to have an eye screening every year, talk to your GP about a referral.
With thanks to 'My Weekly' magazine where a version of this article was originally published.
Disclaimer: This article is for information only and should not be used for the diagnosis or treatment of medical conditions. Patient Platform Limited has used all reasonable care in compiling the information but make no warranty as to its accuracy. Consult a doctor or other health care professional for diagnosis and treatment of medical conditions. For details see our conditions.