Impaired vision twice as common in diabetics

NEW YORK (Reuters Health) - Vision loss is nearly twice as common among U.S. adults with diabetes as those without diabetes, according to research published today.

In a study of more than 13,000 Americans, Dr. Xinzhi Zhang and colleagues at the Centers for Disease Control and Prevention found that 11 percent of adults with diabetes had some degree of visual impairment. That compared with 5.9 percent of those without diabetes.

People with visual impairment have abnormal vision even with the help of corrective lenses. Diabetes is a well-established risk factor, in large part due to a complication known as diabetic retinopathy -- an eye disease caused by damage to the tiny blood vessels supplying the retina.

People with diabetes also have increased rates of glaucoma and cataracts, both of which can lead to vision loss.

Of the 1,237 U.S. adults with diabetes in the study, roughly 4 percent had uncorrectable visual impairment, while about 7 percent had reparable vision loss -- impairment caused by a misshapen cornea.

In comparison, 1.4 percent of adults without diabetes had irreparable vision loss, while 4.5 percent had correctable impairment.

Experts recommend that people with diabetes have an eye exam at least once per year to detect diabetic retinopathy and other eye disorders early, when they are most treatable; good control of blood sugar and blood pressure may also help prevent such eye complications.

According to Zhang's team, the current findings underscore the importance of improving Americans' access to eye care. Diabetes is particularly common among African Americans and Hispanic Americans, who are less likely than whites to have a regular source of health care.

As the U.S. population ages and its demographics shift, the researchers note, the problem of vision impairment "may increase dramatically."

SOURCE: Archives of Ophthalmology, October 2008.