Diabetes can affect your eye in a number of ways:
The most serious eye condition associated with diabetes involves the network of blood vessels supplying the retina. This condition is called diabetic retinopathy.
The unusual changes in blood sugar levels resulting from diabetes can affect the lens inside the eye, especially when diabetes is uncontrolled. This can result in blurring of vision which comes and goes over the day, depending on your blood sugar levels.
A longer term effect of diabetes is that the lens of your eye can go cloudy, This is called a cataract.
Not everyone who has diabetes develops an eye complication. Of those that do, many people have a very mild form of retinopathy which may never progress to a sight threatening condition.
The most serious complication of diabetes for the eye is the development of diabetic retinopathy. Diabetes affects the tiny blood vessels of the eye and if they become blocked or leak then the retina and possibly your vision will be affected. The extent of these changes determines what type of diabetic retinopathy you have. Forty per cent of people with type 1 diabetes and twenty per cent with type 2 diabetes will develop some sort of diabetic retinopathy.
We have divided the risk factors for developing diabetic retinopathy into those you are able to control and those you cannot. Good diabetic control significantly lowers your risk of retinopathy.
The following action reduces your risk of developing retinopathy or helps to stop it from getting worse:
- Controlling your blood sugar (glucose levels)
- Tightly controlling your blood pressure
- Controlling your cholesterol levels
- Keeping fit, maintaining a healthy weight and giving up smoking are all part of good diabetes control.
Nerve damage, kidney and cardiovascular disease are more likely in smokers with diabetes. Smoking increases your blood pressure and raises your blood sugar level which makes it harder to control your diabetes
regular retinal screening (there is more information about this in the following section). The most effective thing you can do to prevent sight loss due to diabetic retinopathy is to attend your retinal screening appointments. Early detection and treatment prevents sight loss.
Annual diabetic eye screening
If you have diabetes this does not necessarily mean that your sight will be affected. If your diabetes is well controlled you are less likely to have problems, or they may be less serious. However, if there are complications that affect the eyes, this can sometimes result in serious loss of sight.
Most complications can be treated, but it is vital that they are diagnosed early.
They can only be detected by a detailed examination of the eye carried out at a specialist screening centre. If you have diabetes your GP or hospital clinic should arrange for you to have annual diabetic eye screening. At this visit you will have eye drops put into your eyes which dilate the pupil and allow the specialist a good view of the retina. A picture is taken using a digital retinal camera and this is looked at in detail to see if there are any changes caused by diabetes.
As you may not be aware that there is anything wrong with your eyes until it is too late, having this regular test is essential. Research shows that if retinopathy is identified early, through diabetic eye screening, and treated appropriately, blindness can be prevented in 90 per cent of those at risk. If you have not had this type of test, ask your GP or diabetic clinic as soon as possible. You should also go for an annual eye test with the optometrist (optician) as the diabetic eye screening test does not replace the regular eye examination.
Some optometrists will take a photograph of the back of your eye as part of your regular eye examination. This photograph does not replace your retinal screening appointment. It is very important to attend both your retinal screening appointment and your regular eye test with the optician.
Treatment for diabetic retinopathy
Most sight-threatening problems caused by diabetic retinopathy can be managed by laser treatment if detected early enough. The aim of laser treatment is to prevent bleeding or to prevent the growth of new blood vessels.
- Early diagnosis of diabetic retinopathy is vital
- Attend your annual retinal screening appointment
- Have an annual eye examination with the optician (optometrist).
Eye examinations are free for people with diabetes.
The importance of early treatment of diabetic retinopathy cannot be stressed enough.
Remember, however, that if your vision is getting worse, this does not necessarily mean you have diabetic retinopathy. It may simply be a problem that can be corrected with glasses. So check it out.