DIABETIC EYE DISEASE

What is diabetes?
As Singapore becomes more affluent and with changing diets that predispose to diabetes, it can be seen from health statistics that diabetes is gradually rising as one of the most common diseases affecting the adult population over 40 years of age. With diabetes comes the many complications brought on by its damaging effect on the small blood vessels that supply the various organs of the body such as the brain, kidneys, limbs and the eye. Severely affected diabetic patients suffer from kidney failure, strokes, gangrene of the limbs which may require amputation and diabetic eye disease.

What is diabetic eye disease?
Diabetic eye disease or diabetic retinopathy, is a condition brought on by the damaging effects of diabetes on the small blood vessels supplying the retina, the nerve layer at the back of the eye which transmits messages to the brain. In the early stages, the retinal blood vessels tend to be leaky. In the advanced stages, the retina that is lacking in oxygen, responds by developing unhealthy new blood vessels which bleed into the back of the eye.

Some Health Statistics
8.5% of the population in Singapore suffer from diabetic retinopathy, with 13.3% of these having sight-threatening retinopathy. All insulin-dependent diabetics and 80% of non-insulin dependent diabetics have retinopathy after 20 years of disease. Diabetic retinopathy as a cause of blind registration has risen from 5.1% in the 1950’s to 47.3% in the 1980’s, and is currently the most common cause of acquired adult blindness in Singapore.

What is the risk of developing diabetic eye disease if one is diabetic?
The longer the duration of diabetes and the worse the blood sugar control, the higher the risk of developing diabetic eye disease. Juvenile diabetics tend to suffer from more severe diabetic eye disease. Good blood sugar control is a very important factor in preventing diabetic eye disease. However, sudden lowering of blood sugar in a poorly controlled diabetic may sometimes worsen the condition. If you have diabetes and high blood pressure at the same time, good control of blood pressure is also important in lessening the risk of developing diabetic eye disease.

How do I know if I have diabetic eye disease?
Diabetic eye disease is insidious in the early stages but if it affects the most sensitive central part of the retina called the macula, then poor vision may be an early symptom. Otherwise, vision may remain good for several years before detection of diabetic eye disease. In the advanced stages, there may be sudden loss of vision from internal eye bleeding.

Can blindness from diabetic eye disease be prevented?
Blindness from diabetic eye disease can be prevented with good control of blood sugar, and blood pressure if high blood pressure is present together. Early detection and prompt treatment during the early stages of the disease are essential in the prevention of blindness.

How is diabetic eye disease treated?
The early stages of the disease can be treated with a special type of laser applied to the damaged parts of the retina. Laser treatment also prevents progression to the more advanced stages where new blood vessels develop. When new blood vessels have formed in the retina, the chances of visual recovery may be poor even with laser treatment. Sometimes, a major operation is needed to clear away internal bleeding.

Should I go for regular eye checks if I have diabetes?
Yes, regular eye checks on a half-yearly or yearly basis are necessary for early detection of diabetic eye disease and prompt treatment where needed. Regular photography of the retina is also important in monitoring the progress of the disease.

Take-home Message
If you have diabetes, regular eye checks and retinal photography to detect early stages of diabetic eye disease followed by prompt treatment if necessary, will go a long way in the prevention of blindness and allowing for a normal lifestyle. Advanced stages of the disease are difficult to treat with poor visual recovery despite laser treatment or surgery.