Diabetic retinopathy is the most common condition afflicting people with diabetes, and can be sight-threatening and is potentially a blinding eye disease. With the increased prevalence of diabetes in Singapore over the past few years, Dr. Ajeet Madhav Wagle, Senior Consultant Ophthalmologist, discusses the condition and how regular eye examinations help to keep diabetic retinopathy in check.
As in many countries, Singapore's population is aging, and the proportion of individuals aged 60 and above is expected to reach 31.9% in 20501. A low mortality rate coupled with a modern lifestyle means the proportion of people living with diabetes is set to increase.
When we think of diabetes, we would probably think of high blood sugar, insulin and high blood pressure. But what about our eyes?
“While the majority of patients with diabetes have no visual symptoms, especially in the earlier stages of the disease, diabetes can affect sight in multiple ways," Dr. Ajeet says.
“In patients with diabetes, vision can get impaired due to diabetic retinopathy and its complications or due to an early onset of cataract. Patients may experience blurred or distorted central vision, reduced contrast vision, sudden onset of floaters or a profound loss of vision.”
In more severe cases, diabetes leads to the abnormal growth of blood vessels in the retina that can rupture and bleed into the eye. Once diabetic retinopathy progresses to these advanced stages, the treatment becomes more complex, and visual impairment can become irreversible.
People who have type 1 or type 2 diabetes are at risk of diabetic retinopathy.
“Diabetic retinopathy is a relatively common condition that affects one in every three diabetics, and about a third of those with diabetic retinopathy develop serious sight-threatening complications. The longer an individual has diabetes, the higher the likelihood of developing the eye disease. More than 90% of those with diabetes for more than 30 years have some form of diabetic retinopathy,” he adds.
While many diabetic patients know that diabetes can affect their eyes, some are unaware that diabetic retinopathy can be present without symptoms.
“At early stages, diabetic retinopathy does not present with any symptoms and vision is not affected. Often when symptoms start to appear, it is already too late and the disease is usually fairly advanced," Dr. Ajeet says.
The speed of progression of diabetic retinopathy is dependent on many factors.
“Generally, the disease progression is faster in patients with poorly controlled diabetes and other risk factors such as high blood pressure, high cholesterol, high body mass index (obesity), kidney disease, heart disease and anemia. Ladies who are pregnant have a high risk of rapid progression of the disease as well. These groups of patients need close monitoring of their retinal condition by the ophthalmologist," Dr. Ajeet advises.
“Regular retinal screening is strongly recommended for all diabetics even if they do not have vision symptoms. On the other hand, any degree of severity of visual symptoms in a diabetic patient warrants a detailed eye evaluation by an ophthalmologist,” he adds.
If diabetic retinopathy is not treated promptly, it can result in severe permanent damage to one’s vision. But fortunately, the risk of developing diabetic retinopathy can be reduced by taking the right steps.
Individuals with well-controlled diabetes and other associated health conditions have a slower gradual progression of the disease over months to years and usually maintain good vision throughout their lives.
“Adopting a healthy lifestyle is very important. In addition to good control of diabetes, one should also optimize one's blood pressure, body weight, and blood cholesterol levels. Going for regular eye screening to pick up any diabetic retinopathy early is also very critical," Dr. Ajeet advises.
Regular dilated eye examinations can track disease progression, and controlling your blood sugar can prevent the condition from worsening. However, if your vision is already affected, treatment should be initiated promptly.
“Special drugs such as anti-vascular endothelial growth factor (anti-VEGF) agents and sustained-release steroid implants are placed in the back of the eye to control leakage from diseased retinal blood vessels. Traditional laser surgery is another treatment option to seal the blood vessels,” he explains.
“For some diabetic patients with advanced retinal disease, newer small-gauge instruments can be used in a complex surgery, called a vitrectomy, to salvage some useful vision. However, a proportion of such patients may still end up with poor visual recovery despite treatment,” he adds.
Early detection and treatment will help to prevent significant vision loss from diabetic retinopathy. The earlier the detection of the disease, the less invasive the treatment will need to be.