• Glaucoma is one of the leading causes of blindness in the United States, and the most common cause of blindness among African Americans. More than three million people have glaucoma, but half do not realize it because there are often no warning symptoms.
• Approximately 24 million people in the United States have diabetes and nearly one-quarter of them do not know it. Diabetes is the leading cause of new blindness among adults and people with diabetes are 25 times more likely to become blind than people without it. By detecting and treating diabetic retinopathy early through annual, dilated eye exams, people with diabetes can preserve their sight.
• Age-related macular degeneration  (AMD) is a leading cause of vision loss in people 65 years or older in the United States. It affects more than 10 million Americans according to the National Eye Institute.

Last reviewed and updated in February 2009,
by the American Academy of Ophthalmology.