The eye condition known as age-related macular degeneration (AMD) has long been associated with blindness, since no drug or surgical procedure has been able to halt the disease's progression.
Now: New treatments, including a simple nutritional therapy, have given hope to the up to 10 million Americans who suffer from the early stages of AMD.
If caught before permanent damage has occurred, the most serious form of AMD can be stabilized in 90% of people with the condition--and one-third even may experience improved vision.
Are You At Risk?
The incidence of AMD is on the rise-primarily due to the "graying" of America. As Americans live longer, AMD, which grows more common with age, affects increasing numbers of adults. Almost one in three Americans over age 75 has it. Obesity, which is strongly linked to increased risk, also remains high. Other risk factors…
- Family history, which increases risk due to a likely genetic component to AMD. If a close relative (parent or sibling) has had AMD, your own risk is greater.
- Stroke and "mini" strokes, which often are referred to as transient ischemic attacks (TIAs). Both result in a substantially higher risk for AMD. This increased risk is thought to be due to injury to the blood vessels, which occurs with strokes, TIAs—and AMD.
- Cigarette smoking, which increases oxidative stress throughout the body. It can quadruple the chance of developing AMD. Quitting will reduce the danger, but you're still at higher risk than people who never smoked.
Damage Is Progressive
AMD occurs when there is a deterioration of the tissue in the macula, the central area of the light-sensitive retina.
There are two forms of AMD…
- Dry macular degeneration. In up to 85% of AMD cases, deposits of protein and cholesterol called drusen develop among the pigmented cells behind the macula. These deposits cut retinal cells off from their blood supply, depriving them of nutrients and oxygen, leading to the accumulation of waste products.
- As the drusen grow, central vision gets blurry. If the degenerative process continues, a blind spot may develop in your central vision.
- Wet macular degeneration. This form of AMD, which typically develops from the dry form, is responsible for the bulk of serious vision loss. Damage to the retina spurs the formation of fragile new blood vessels that often leak fluid or blood into the area around the macula. If untreated, wet macular degeneration often progresses rapidly-and within weeks or months, sight may deteriorate to the point of legal blindness.
Don't ignore the red flags: Because the progressive vision loss of AMD often can be halted, it is essential to spot the disease and start treatment as early as possible. If you notice changes in central vision (such as difficulty recognizing faces)...a decline in your ability to distinguish colors and details.. and/or night blindness (inability to see in very dim light), see an eye specialist (ophthalmologist or optometrist) promptly.
Important: AMD can start in one eye while the other remains normal. This can make changes in vision difficult to notice until they become pronounced and affect both eyes.
Best approach: Schedule a yearly eye exam, particularly after age 65, to spot early signs of AMD. The doctor should use drops to dilate the pupils so he/she can see the retinas clearly with a magnifying instrument. To monitor your eyesight between visits to your doctor, check your vision daily with an Amsler grid.
A large clinical trial sponsored by the National Eye Institute found that a high-dose mixture of antioxidants and zinc could slow the disease in a substantial number of people with dry AMD.
For patients with varying stages of AMD, a supplement containing vitamin C-500 milligrams (mg)...vitamin E-400 international units (IU)...beta-carotene-15 mg...and zinc-80 mg, with 2 mg of copper to prevent deficiency of that mineral, reduced the risk for progression to an advanced stage of the disease by about 25%, compared with a placebo. This formulation, known as AREDS (Age-Related Eye Disease Study), can be found in a single supplement at drugstores
If you have early AMD: Increase your dietary intake of dark green, leafy vegetables, which contain the nutrients described above... and cold water fish, for their omega-3 fatty acids. Red wine, which contains antioxidants, also may protect against AMD. If you smoke, it's crucial that you stop.
If you have intermediate AMD or advanced AMD in one eye: Take the supplement combination described above along with a daily multivitamin, if you like). In addition, follow the dietary guidelines described above.
New Drug Treatments
Until fairly recently, wet AMD made severe vision loss a near certainty, but new medications have enabled many people to preserve their sight. Anti-VEGF (vascular endothelial growth factor) drugs stop production of fragile new blood vessels by blocking the action of a protein that blood vessels need to develop. These drugs are injected into the eye monthly.
- Ranibizumab (Lucentis) is the first antiVEGF drug to receive FDA approval for AMD. In clinical trials, it stabilized vision in nearly all the patients who used it for a year...and up to 34% registered significant improvements in sight. The effects appear to increase over time.
- Bevacizumab (Avastin) has been approved for the treatment of colorectal cancer, but appears to be equally effective when administered intravenously for wet AMD.
- Aflibercept (VEGF Trap), another anti-VEGF drug, is being studied for treatment of AMD. It is given every other month.
- Photodynamic therapy is an older approach that involves the injection of the drug verteporfin (Visudyne) into the bloodstream. When a laser beam activates the chemical within the eye, it seals off abnormal blood vessels. Photodynamic therapy is less effective than anti-VEGF drugs and will slow-but may not stop-vision decline. Nowadays, photodynamic therapy has mostly been supplanted by anti-VEGF drugs. A study is under way to determine whether combining the two will be more effective than either alone.
On The Horizon
New scientific research is focusing on AMD prevention. For example, one recent study suggests that a protective effect may be offered by…
- Lutein and zeaxanthin. Research has found that the plant-based antioxidants lutein and zeaxanthin may reduce the risk for intermediate and advanced AMD in women under age 75. It is believed that these antioxidants provide protective effects for men as well.
Now, a major trial is under way to determine if a supplement with these nutrients and omega3s might halt progression of the disease.
If you are age 65 or older, call the Foundation of the American Academy of Ophthalmology's EyeCare America at 800-222-3937 to see if you qualify for a free eye exam in your area.
Improve Your Vision
In a study of 22 adults, participants who I played an action video game for 50 hours over nine weeks had a 43% improvement in contrast sensitivity-one of the first visual abilities to decline with age—while those who played a slow-moving video game did not improve. The benefits lasted for several months after the study.
Theory: Action video games may fine-tune the visual-processing pathways in the brain for challenging visual tasks, such as night driving.