Dr. Scott Lewis was asked some questions about Diabetes- this is part 1 of his answers.
Q: What does the diagnosis of Diabetes or Diabetic Retinopathy mean exactly? I’ve heard there are different types?
There are both different types of diabetes, as well as different forms of diabetic retinopathy.
The pancreas is the organ responsible for making a hormone called insulin, which is used to help glucose get into the cells of the body. When a patient has diabetes, either the body doesn’t make enough insulin, or is unable to use its insulin properly.
Type 1 diabetes is an autoimmune condition where the body attacks and destroys cells that produce insulin. About 10% of people with diabetes have Type 1.
Type 2 diabetes was previously called non-insulin-dependent diabetes mellitus (NIDDM) or adult-onset diabetes. In Type 2 diabetes, the body doesn’t make enough insulin, or the insulin it makes doesn’t work properly and glucose builds up in the blood. About 90% of people with diabetes have Type 2.
Diabetic retinopathy is the term used to describe damage to the retina from diabetes. Diabetic retinopathy is the leading cause of blindness in American adults, affecting approximately 7.7 million individuals
There are two major classifications of the disease: nonproliferative diabetic retinopathy (NPDR) and proliferative diabetic retinopathy (PDR). NPDR is further classified into mild, moderate, and severe. Proliferative diabetic retinopathy is the most severe stage, where new blood vessels grow in the retina. These vessels are abnormal and hemorrhage easily. PDR has the greatest risk of visual loss.
Q: I understand that Diabetes is common among those over 40 or with weight issues. Are there other groups that are at a higher risk?
In addition to the risk factors you mentioned, it has been shown that people of certain races – including African-Americans, Latinos, Native Americans, and Asian-Americans are at higher risk for type 2 diabetes.
Your risk also increases if you have a family history of the disease. Having high blood pressure over 140/90 and abnormal cholesterol and triglyceride levels are also linked to an increased risk of type 2 diabetes.
Q: Please describe the typical progression for an individual with Diabetes regarding their eyesight?
Most newly diagnosed patients with diabetes have no abnormal findings in their vision exam. The two most important factors that put patients at risk for developing diabetic retinopathy are duration and glycemic control.
Approximately 25% of Type 1 patients have some retinopathy after five years. These numbers increase to almost 60% after 10 years and greater than 80% after 15 years.
The most important measurement in determining glycemic control is the HbA1c number. The A1c measures the average blood glucose during the previous 2-3 months. Generally, an A1c under 7% is recommended for patients with diabetes.
Q: What happens during a typical Diabetic Eye Exam?
The eye is the only place in the body where doctors can look at blood vessels. This is why eye exams are so important for patients with diabetes.
The standard of care for patients with diabetes is to have a dilated retinal evaluation. Drops to widen the size of the pupil are used in the exam, and both the central and peripheral retina is examined for signs of changes due to diabetes. In addition to being dilated, we also suggest that patients with diabetes have an ultra widefield retinal image taken of their retina with the Optomap. Serial images taken over time can help assess subtle changes in retinal health.
Part 2 of Dr. Lewis' answers will be posted soon.