Illustration by Gianpaolo Pagni
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Lifting the Veil
By Miriam Karmel, November & December 2007
New treatments for age-related macular degeneration offer hope for vision
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Irene Thompson can’t tell whether her counters are clean. To read bills, the 76-year-old retired nurse needs an electronic magnifier so powerful that just a few words fill a whole TV screen. And she avoids going to parties “because there will be people across the room that I should recognize and I don’t,” says Irene, who lives with her husband, Kenneth, on a 150-acre farm in southern Minnesota.
Irene has age-related macular degeneration (AMD), a common and pernicious disease that destroys clear vision. With AMD, “everything is much slower,” she says. “Living just takes a lot longer.”
Until recently, most AMD patients had little hope for halting the deterioration of their eyesight. Laser treatments helped a few, but most patients were not candidates. Now, a new class of medicines is halting AMD for many—and for some people, even restoring a bit of vision. “It’s almost like we’ve come out of the Dark Ages in the past five years,” says Sharon Fekrat, M.D., F.A.C.S., an associate professor of ophthalmology at Duke University in Durham, North Carolina.
The Enemy Within
AMD is the leading cause of vision loss for Americans over 50. About 1.8 million have advanced AMD, and another 7.3 million are at substantial risk of losing vision to the disease.
There are two forms of the condition. The first, known as dry AMD, involves small white or yellow protein-and-fat deposits called drusen; these accumulate under the eye’s macula, an area at the rear of the eyeball. Symptoms of dry AMD include blurred vision, a need for brighter light to read by, and a lessening of color contrast.
There is no medically sanctioned treatment for dry AMD, though a specially formulated vitamin supplement has been shown to slow progression of the disease in some people (see “Preventive Measures,” below).
Most cases of AMD are dry. But for 10 percent of sufferers, the disease takes a more aggressive form: wet AMD. This is characterized by the growth of abnormal, fragile new blood vessels at the back of the eye that leak blood or fluid under the macula. Symptoms include visual distortions—such as straight lines appearing wavy—and blind spots (see “Test Yourself,” below). This devastating disease does have one saving grace, however: because peripheral, or side, vision is rarely affected, wet AMD patients usually retain some of their eyesight and can learn to function using mechanical aids such as magnifiers and telescopes.
Sight Savers
Though nothing can completely reverse the damage of wet AMD, new treatments can minimize it. The first of these arrived in 2000, when a laser technique called photodynamic therapy (PDT) was approved by the FDA. In some patients PDT can destroy unwanted blood vessels.
Then, in fairly rapid succession, three drugs designed to inhibit new blood vessel growth were introduced. Macugen (pegaptanib) was the first, but it didn’t produce the dramatic results that researchers were observing in clinical trials of Lucentis (ranibizumab), a drug injected directly into the eye every four weeks. In one two-year study, about 95 percent of patients treated with Lucentis saw little or no worsening of their vision. In a separate, one-year study, 40 percent of patients noticed their vision actually improving.
The Lucentis results were so promising that in 2004, two years before the drug was approved by the FDA, a doctor at the University of Miami took the bold step of injecting patients with a related medication, Avastin (bevacizumab), which had already been approved for the treatment of colorectal cancer. The off-label use seemed to work, and within a short while, ophthalmologists worldwide were using Avastin. And they’re still using it, even after the FDA approved Lucentis specifically for eye care.
Most physicians regard Avastin and Lucentis as medically similar, says Fekrat, though Avastin is typically injected every six to eight weeks; Lucentis, every four. The big difference between the drugs is the price. A typical dose of Avastin costs $75. One dose of FDA-approved Lucentis costs $2,067. But some insurers won’t cover Avastin for any use other than cancer treatment, which makes Lucentis, despite its price tag, the cost-effective choice for some. Many doctors say they choose between the two drugs based mainly on what the patient can afford.
Irene Thompson began regular Avastin treatments and so far hasn’t experienced much further deterioration of her eyesight, as she might have without treatment. Now, she’s waiting to see whether her vision gets better.
Other patients have been luckier. Barbara Frantz, 75, developed AMD in her right eye before Avastin was available. Today she has little vision in that eye. When the disease occurred in her left eye, her doctor immediately treated it with Avastin. After two years of regular treatments, her vision is clear, she is still driving, and as the owner of a knit shop in Wilson, North Carolina, she is grateful to be teaching customers and working on her own creations.
Avastin isn’t a cure, though. And doctors don’t know if there is a limit to how many injections a person can receive. So Barbara is grateful for what vision she has. “I count every month as, ‘Yay! I can still see,’” she says. “Actually, I count every day that way.”
Minneapolis freelancer Miriam Karmel regularly reports on eye disease.
TAKING CHARGE OF YOUR VISION
Test Yourself
In addition to regular eye exams, an at-home eye chart called the Amsler grid can help you identify AMD when it first appears.
Click here for chart
Preventive Measures: What you can do to keep AMD at bay
These healthy habits have been linked to lower rates of AMD:
Don’t smoke.
Eat a diet rich in fish, fruit, and green, leafy vegetables.
Avoid high-fat foods.
Exercise.
Control your blood pressure and weight.
In addition, everyone older than 70 should have a dilated eye exam every one to two years.
If you have dry AMD, a special formulation of high-dose antioxidant vitamins with minerals may slow the disease’s progression. Patients who took the supplement showed a 25 percent lower risk of progression than those who took a placebo in the Age-Related Eye Disease Study (AREDS), sponsored by the National Eye Institute.
The supplement, available commercially, includes 500 milligrams (mg) of vitamin C, 400 international units of vitamin E, 15 mg of beta carotene, 80 mg of zinc oxide, and 2 mg of copper as cupric oxide. Consult your doctor before taking this supplement.
Living With AMD: Making the most of your vision
Many AMD patients stop trying to use their eyes, says Lylas G. Mogk, M.D., coauthor of Macular Degeneration: The Complete Guide to Saving and Maximizing Your Sight (Ballantine, 2003): “They say, ‘I can’t read the paper; that’s okay.’ ”
But it’s not okay. The less you do, the less you’ll be able to do. And that’s a recipe for depression, which is a frequent side effect of the disease.
Here are some tips for getting the maximum use of your remaining vision:
Seek therapy A specially trained occupational therapist can help you adjust. To find one, go to www.visionconnection.org.
Increase contrast Make mealtimes easier by serving light foods on dark plates and vice versa. Use plain linens so items don’t get lost in the pattern.
Use aids Give your eyes a boost with bright, direct lighting; magnifying devices; large-faced TV remotes; and talking clocks.
Reduce glare Wear yellow- or plum-tinted glasses indoors; dark yellow, amber, or plum lenses and a visor outdoors.
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