Why do African-Americans have a higher risk of glaucoma than whites?

Researchers have found that oxygen levels are significantly higher in the eyes of African-Americans with glaucoma than in whites with the disease. They suspect that more oxygen may damage the drainage system in the eye, resulting in elevated pressure. Higher pressure can damage the optic nerve, causing blindness. The study provides the first physiologic clue about the link between race and risk for glaucoma. Glaucoma is the leading cause of blindness among African-Americans. Compared to whites, glaucoma is about six times more common in African-Americans, and blindness caused by glaucoma is roughly 16 times more likely in African-Americans. The findings suggest that there may be physiologic differences in oxygen metabolism between African-Americans and whites.