Study assesses glaucoma risk factors among Native Americans

SARASOTA, Fla. — Native Americans have a higher incidence of normal-tension glaucoma than white patients, according to results of the Northwest Trial Vision Project.

While vision loss is the second-leading cause of impairment and the sixth-leading cause of disability for Native Americans, the vision project is the first to calculate the incidence of glaucoma in this population, according to Steven L. Mansberger, MD, who spoke here during the American Glaucoma Society meeting.

The vision project included 289 participants who were randomly selected from three tribes and were at least 40 years old. All participants received a full physical examination and an ophthalmic examination that included refraction, frequency doubling technology, limbal anterior chamber depth, confocal scanning laser ophthalmoscopy, nonmydriatic digital imaging and tonometry.

Patients with abnormal results and 30% of patients with normal results then underwent a full dilated exam.

Investigators found that 31% of patients had a complete screening pass with no detectable abnormalities, 23% had diabetes and 11% had a visual acuity of 20/40 or worse.

None of the patients had an IOP greater than 21 mm Hg, and the mean IOP was 12.9 mm Hg. Native American patients also had a higher cup/disc ratio than whites, Dr. Mansberger said.