Researchers say the five-year study, funded by the National Institutes of Health, is the largest of its kind and may indicate a greater need for eye-care outreach to the Latino community.

"Because Latinos have high rates of eye disease, they should get regular eye exams at least once a year, especially if they are age 50 or older," said study director Dr. Rohit Varma, an associate professor of ophthalmology and preventive medicine.

Overall rates of vision problems among U.S. Latinos are high, and older Latinos have the highest rates of visual impairment among all other racial or ethnic groups in the country, said Varma.
He said a genetic predisposition to eye disease and a lack of sufficient eye care among many Latinos may account for the disparity.

Higher rates of diabetic retinopathy, a complication of diabetes, in the Latino population are closely tied to high rates of diabetes.

According to the American Diabetes Association, 2 million U.S. Latinos age 20 or older have diabetes. The prevalence of type 2 diabetes is 1.5 times higher in Latinos than non-Latino whites.

The researchers noted almost one in four participants had diabetes, and 20 percent of them were not aware of their condition until the study. Of those with diabetes, nearly half also had some signs of diabetic retinopathy, and many did not know they had an eye disease.

The Los Angeles study found 4.74 percent of participants had open-angle glaucoma, a disease that puts pressure on the eye's optic nerves. According to data from the National Eye Institute, the overall rate for people in the United States age 40 and older is about 1.86 percent.

"The numbers are illuminating," showing that many Latinos have undiagnosed eye disease, said Dr. Dipali Apte, a regional glaucoma consultant for Kaiser-Santa Clara hospital.

Lack of routine eye care among Latinos is one complicating factor with glaucoma, Varma said. Among participants, 35 percent said they were uninsured.