Diabetes, Hypertension increases risk of developing open-angle glaucoma (OAG)

In an online study published in the journal Ophthalmology, researchers at the University of Michigan Kellogg Eye Center report that the risk of developing open-angle glaucoma (OAG) is higher for many Americans who suffer from hypertension and diabetes.

The billing records of over 2 million people in the age group of 40 and above were reviewed by a team led by Joshua D. Stein, M.D., M.S., a glaucoma specialist at Kellogg. These people were a part of a managed care network in the US, and made appointments with an eye specialist once or twice between 2001 and 2007.

Study findings reveal that the risk of developing OAG was 35% higher in people with diabetes, 17% higher in people with hypertension, and 48% higher for people with both conditions.

Metabolic syndrome is a collective set of conditions including hypertension, diabetes, obesity, and hyperlipidemia (high cholesterol and high triglyceride levels) that impinges upon one fifth of the U.S. population. Kellogg researchers looked into the possible relationships between various components of metabolic syndrome, and the role played by each component in increasing or decreasing glaucoma risk.

Findings of the study revealed that OAG risk was elevated in diabetes and hypertension while it was reduced by 5% in hyperlipidemia. Researchers are looking into the causes that reduce glaucoma risk: whether it is the hyperlipidemia itself, the medications, or both. Results of this study may facilitate the development of novel treatments for glaucoma.

Dr, Stein said, “Patients who have diabetes and hypertension are already known to be at elevated risk for eye conditions like diabetic retinopathy, a condition that harms the blood vessels in the retina. This study and others suggest that, for these patients, an increased likelihood of glaucoma is also a concern.”

Glaucoma diagnoses are expected to swell up with the aging US population. The condition affects over 2.2 million Americans and is the major cause of permanent blindness globally. Most often, OAG symptoms do not surface until the disease had advanced. Hence, in order to recognize patients that may benefit from screening and monitoring, physicians will have to understand the risks linked with OAG elevated intraocular pressure, increased age, positive family history of glaucoma, and non-white race.

Dr. Stein says, “This study reinforces the importance of regular eye examinations for patients at increased risk of glaucoma, including those with diabetes and hypertension.”
The study was funded by grants from the National Eye Institute.