What is the leading cause of blindness in adults?

• A. Open-angle glaucoma
• B. Macular degeneration
• C. Diabetic retinopathy
• D. Retinal artery/vein occlusion

Answer: (C)

Chronic diabetes damages the tiny blood vessels of the retina, so diabetic retinopathy becomes the leading cause of blindness in adults. High blood glucose over time weakens and closes retinal capillaries, leading to microaneurysms, hemorrhages, and cotton-wool spots in nonproliferative stages. As it progresses to proliferative retinopathy, new, fragile vessels grow on the retina and into the vitreous, risking severe vision loss from vitreous hemorrhage or tractional retinal detachment. The key to preventing blindness is early detection with regular dilated eye exams and tight control of blood sugar, blood pressure, and lipids. While macular degeneration and glaucoma are major causes of vision loss, they affect different populations and are not the primary cause of blindness in adults with diabetes.