Age-related macular degeneration (AMD) is the leading cause of severe vision loss in the United States for people age 65 and older. AMD causes damage to the center of the retina, called the macula, and therefore disrupts central vision. Because the center of the retina allows us to see detail, damage to this area can limit everyday tasks like reading, driving or watching television.
Q: What can I do to prevent AMD?
A: Since macular degeneration is an aging change, following a healthy lifestyle is the best way to keep your eyes young. Most importantly, eat a low-fat diet high in green leafy vegetables and fish. These foods are particularly high in antioxidants that limit aging. Regular exercise, not smoking, protecting your eyes from the sun’s ultraviolet light, and maintaining normal blood pressure have also been shown to reduce risk of macular degeneration.
See your eye doctor yearly for a thorough eye health evaluation. If you have a family history of AMD or your doctor identifies an early warning sign of macular degeneration, called drusen, then diet becomes even more important. You may need to supplement your diet with a high-dose formulation of antioxidant vitamins and minerals based on the Age-Related Eye Disease Study (AREDS). In this long-term study, high-potency supplements of vitamins C, E, beta-carotene and zinc were found to decrease the risk of advanced AMD by about 25 percent.
Q: Can lutein and zeaxanthin supplements prevent AMD?
A: The carotenoids lutein and zeaxanthin are compounds called xanthophylls, which are yellow pigments that occur naturally in many plants and vegetables. They are also found in the macula of the eye, along with a third xanthophyll, meso-zeaxanthin. Scientists believe that lutein, zeaxanthin, and meso-zeaxanthin in the macula block blue light from reaching the underlying structures in the retina, thereby reducing the risk of light-induced oxidative damage that could lead to AMD. While some studies have shown that nutritional supplementation of lutein and zeaxanthin may help revent AMD, other studies were inconclusive. The National Eye Institute is currently sponsoring a second Age-related Eye Disease Study (AREDS 2) to evaluate the effect of lutein and zeaxanthin and two omega-3 fatty acids (EPA and DHA) on the progression of AMD. Lutein and zeaxanthin are found in vegetables such as spinach, corn and peppers, and in some vitamin formulations.
Q: What treatments are available for AMD?
A: Most treatments for AMD are limited to patients with the wet form of the disease. Less common than the dry type, wet AMD occurs when abnormal blood vessels grow, leak and bleed behind the retina, usually leading to significant vision loss. In addition to conventional laser treatment, newer therapies have been approved in recent years for wet AMD. Anti-angiogenic drugs designed to stop abnormal blood vessel growth associated with wet AMD have shown improved vision in a significant number of patients. These drugs may be combined with Photodynamic Therapy (PDT) with the goal of minimizing further visual loss. Other treatments, such as acupuncture, are also being investigated.
Q: What remedies are available if I develop AMD?
A: There are a wide variety of low vision devices available that help improve vision for different tasks. For example, high power magnifiers are available mounted on stands to place over reading material, mounted on eyeglass frames, or they may be handheld. Low vision computer aids can scan and enlarge printed material for easier viewing.
Julie Danielson, an optometric physician, is available by appointment at Jacksonville Vision Clinic 899-2020.