Age-related macular degeneration (AMD) is a degenerative condition of the macula, which is the portion of the retina responsible for central vision. It is the most common cause of irreversible vision loss in the United States in those 60 or older, and its prevalence increases with age. Scientists believe that AMD is caused by the degradation of the arteries that nourish the retina. This deprives the sensitive retinal tissue of oxygen and nutrients that it needs to function and thrive. As a result, the central vision deteriorates gradually and painlessly.
No one knows the cause of AMD. Causes are likely to be genetically inherited, but environmental factors may also contribute. Macular degeneration often runs in families. Women have a higher risk of developing AMD than men. There may be a wide variety of different genes and proteins associated with dry and wet macular degeneration.
Many risk factors have been found to be associated with AMD. These include age, family history, light-skin, light-colored iris, poor nutrition, obesity, smoking, and exposure to sunlight.