The real tragedy behind vision-stealing glaucoma is that most people afflicted with this eye disease do not even realize they have it. As a result, the condition goes undiagnosed and untreated, which too often leads to unnecessary blindness. Of the 2.7 million people in the United States with glaucoma, half are undiagnosed. Most are lulled into a false sense of confidence because glaucoma often displays no symptoms in its early stages. By the time it begins to affect vision, any lost sight is impossible to regain. The risk of developing glaucoma begins to increase dramatically at midlife, which is why everyone should have a baseline exam by age 40. The most important concern is protecting your sight. Doctors look at many factors before making decisions about your treatment. If your condition is particularly difficult to diagnose or treat, you may be referred to a glaucoma specialist. While glaucoma is most common in middle-aged individuals, the disease can strike at any age, with those having a family history of the disease is especially vulnerable.