Keep an eye out for glaucoma.

It was once thought that high intraocular pressure (IOP) was the main cause of this optic nerve damage. Although IOP is clearly a risk factor, we now know that other factors must also be involved because even people with "normal" IOP can experience vision loss from glaucoma. The two main types of glaucoma are primary open angle glaucoma and angle closure glaucoma. People at higher risk include African-Americans, diabetics, people over 60 years old, people who are or were severely nearsighted, and people taking high doses of steroids such as asthma inhalers. Three million people in the U.S. have glaucoma but it is estimated that only half are now aware of it.