Homocysteine: Link Between Nutrition and Diabetic Eye Disease?

---

Homocysteine and diabetic retinopathy, by Liama Brazionis and colleagues. Diabetes Care 31:50-56, 2007

What is the problem and what is known about it so far?

Homocysteine is an amino acid found in the blood stream after eating certain foods.  Recently, it has gained the attention of doctors and researchers who believe homocysteine may be a risk factor for heart disease and eye problems. This makes an interesting link to diabetes because diabetes also leads to both heart disease and retinopathy (damage to small blood vessels in the eyes that can lead to blindness).

Why did researchers do this particular study?

Earlier studies have looked at retinopathy in people with diabetes and its connection to homocysteine, but none of these studies ended with the same results. Each had used different methods, and they were not looking directly at the connection between homocysteine and diabetes. Researchers in this study tried to narrow the study to test if high levels of homocysteine in the blood stream may be a sign of retinopathy in people with type 2 diabetes.

Who was studied?

168 people with type 2 diabetes

How was the study done?

Using a group of volunteers from Melbourne, Australia, researchers took blood samples to test the A1C score (a measure on long-term blood glucose control) and for homocysteine and cholesterol levels. They also took photographs of volunteers’ eyes to check for retinopathy. Volunteers then answered a “lifestyle questionnaire” about their habits, such as smoking and alcohol use. Researchers used all this information in a formula to look at the relationship between retinopathy and homocysteine levels.

What did researchers find?

Researchers found that 48 percent of people with type 2 diabetes who also suffered from retinopathy had high levels of homocysteine in their blood.  Only 30 percent of everyone with type 2 diabetes had high levels of homocysteine. This made researchers believe that there is a definite relationship between retinopathy and homocysteine levels.

What are the studies limitations?

The study did try to keep known causes of retinopathy (having diabetes for a long time and high A1C levels and blood pressure) and of high levels homocysteine (age and gender) from affecting the results. However, they did not watch for other known causes such as genetics and some personal habits. Another study is needed to confirm the results.

What are the implications of the study?

For doctors, increased homocysteine may show that if not cared for properly, a patient with type 2 diabetes will develop retinopathy and other complications from diabetes, such as nephropathy (nerve damage) and heart disease.

For people with type 2 diabetes, simply changing to a diet full of fresh fruit and vegetables can control and lower homocysteine levels and decrease the risk of diabetes complications, such as retinopathy.

FOR MORE INFORMATION

Eye Complications

Eye Care

Virtual Grocery Store

All Natural Diabetes Cookbook