Eye Damage in Hypertension and Diabetes

New research reveals how high blood pressure affects vision in diabetes patients. Both high blood pressure and eye problems are common complications of diabetes.

A recent animal study showed that the combination of diabetes and high blood pressure may lead to cell death and blood vessel damage in the eyes, causing impaired vision.

Azza El-Remessy, PhD, of the University of Georgia conducted the study and was the first to explain why blood vessels in the eye are damaged by high blood pressure, or hypertension, combined with diabetes.

"Results showed early signals of cell death in eyes from diabetic animals within the first six weeks of elevated blood pressure," says Dr. El-Remessy. "Later, the tiny blood vessels around the optic nerve that nourish the retina and affect visual processing showed signs of decay as early as 10 weeks after diabetic animals develop hypertension," she says.

Even though the study was done on animals, the results underline the importance of tight control over blood pressure and blood sugar in people with diabetes. Diabetes patients, who can control their blood pressure and blood sugar, may reduce their risk of diabetes-related vision loss.

Islam Mohamed, a University of Georgia graduate student and co-author of the study added that, many major studies have shown that diabetes patients benefit from controlling their blood pressure. The results highlight the interaction between high blood pressure and diabetes, as two independent risks for eye damage, says Mohamed.

"This emphasizes the importance of addressing different cardiovascular risk factors in a holistic approach for improving management and prevention of retinopathy," he says. In other words, the results call attention to the need for controlling heart-related problems in order to prevent eye damage.

"Health care providers, including pharmacists, should stress the importance of the tight control of blood sugar and blood pressure levels for their patients," says Dr. El-Remessy. "Providing patient education and counseling on how each of these metabolic problems independently can have accelerated devastating effects is critical and can result in better prevention and outcomes for the patients," she says.

For their study, the researchers compared a group of rats with high blood pressure to another group with high blood pressure and diabetes.

Molecular Vision, June 2012