Zinc may help against vision loss in elderly
An inexpensive over-the-counter antioxidant/zinc supplement that may help preserve vision in older people is also cost effective, a new study suggests. The combo pill has been dubbed the “Age-Related Eye Disease Study (AREDS)” supplement, based on trial in which it was studied previously.
Dr. Aaron Lee, a researcher on the new trial, said his team found AREDS was “greatly cost-effective for the treatment of age-related macular degeneration, specifically in people who have active wet, age-related macular degeneration in one eye and dry in the other.” Lee is assistant professor of ophthalmology at the University of Washington in Seattle, United States (U.S.).
The new study suggests the AREDS supplement may delay the need for more expensive treatment of the “wet” form of the illness, especially, Lee said. The study was published Aug. 23 in the British Journal of Ophthalmology.
Exactly how the supplements work to slow progression of the eye malady isn’t known, he added, but “the current formulation of the supplements contain antioxidants that are thought to be protective of the retina from damage that results in wet age-related macular degeneration.”
Still, at least one U.S. eye expert challenged the idea that the AREDS supplement definitively showed a benefit in preventing the disease or its progression. “Despite this being routine practice among many retinal specialists in the U.S., the benefits remain uncertain,” said Dr. Alfred Sommer, professor of ophthalmology at Johns Hopkins University School of Medicine in Baltimore.
According to the American Macular Degeneration Foundation (AMDF), age-related macular degeneration causes damage to the macula, a small spot near the center of the retina. It’s the part of the eye needed for sharp, central vision. Over time, vision can become blurry, and eventually patients can lose their eyesight.
The two basic types of macular degeneration are called wet and dry. About 10 percent to 15 percent of the cases of macular degeneration are the wet type.
In wet macular degeneration, blood vessels grow under the retina and macula. These new vessels may bleed and leak fluid, causing the macula to bulge or lift up from its normally flat position, thus distorting or destroying central vision. Vision loss may be rapid and severe.
Approximately 85 percent to 90 percent of the cases of macular degeneration are the dry type. Dry age-related macular degeneration does not involve any leakage of blood. Instead, the macula may deteriorate and waste products from cells in the eye can build up. Loss of vision can occur, according to the AMDF.
The prior AREDS trial showed that the supplements, which combine antioxidant vitamins with zinc and copper, are inexpensive and effective in slowing the progression of age-related macular degeneration.
AREDS supplements are sold under brand names such as PreserVision and Pro-Optic. Costs range from about $25 to $40 for 120 pills — a two-month supply.
That’s a much lower price tag than expensive prescription drugs called anti-VEGF therapies, which are currently used to treat wet macular degeneration. Plus, anti-VEGF drug therapy involves getting a needle in the eye, and the drugs can also have side effects. One possible side effect is an increased risk of inflammation of the inside of the eye, and another possibility is stroke, Lee noted.
So, to calculate the cost-effectiveness of AREDS supplements, Lee and colleagues looked at the use of the supplements in people over 55 years of age.
The AREDS trial had concluded that a daily supplement combining high-dose antioxidants and zinc lowered the risk of developing wet age-related macular degeneration and slowed its progression.
Lee’s team looked at two formulas of available supplements. Formula 1 has high doses of vitamins C and E, beta carotene, zinc and copper. Formula 2 has lutein and zeaxanthin instead of beta carotene.
The researchers used a statistical model with information from the AREDS trial, along with data from more than 90,000 people with macular degeneration in the United Kingdom.
The investigators found that both formulations were cost effective for treating patients with early stage disease, but they were even more cost effective for those with the condition in only one eye.
Over the course of a lifetime, the researchers found that these patients would need nearly eight fewer injections of anti-VEGF therapies into their eye, Lee said. That could lead to thousands of dollars in savings per patient over time, the British team concluded.
But Sommer, who reviewed the new findings, did have some caveats. According to Sommer, no large-scale study has been done to test that out. And the AREDS trial researchers used to tout these supplements was small, so that any positive results might still be a chance occurrence, he noted.
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