Vitamin Supplements and age-related macular degeneration(AMD)

In 2001, the researchers of the Age-Related Eye Disease Study reported their landmark findings that patients with dry AMD who took a combination of antioxidants and zinc experienced a decrease in disease progression.
The study divided the patients based on severity of their AMD: mild disease (category 1); intermediate disease (categories 2 and 3); and advanced disease (category 4). The primary endpoints of the AREDS trial were progression to advanced AMD and the degree of vision loss.

They recommended vitamin supplementation only in patients with either intermediate disease or advanced disease in only one eye. There was a clear benefit in these patients, as they demonstrated decreased visual loss and decreased progression to more advanced stages of AMD. The results of the study showed no clear benefit in the patients with category 1 disease (those with only very small drusen in the macula).
These results recommend vitamins to all but two large cohorts of patients, the first of which is patients with category 1 disease. Even in a 10-year follow-up study with patients from the original AREDS report, there was no significant difference in the progression of disease in category 1 patients receiving placebo versus therapy, confirming the original study’s position of not recommending vitamin use to patients with only mild disease.
The second group of patients for which vitamin use isn’t recommended is those with significantly advanced disease that severely affects not just one eye, but both of them. However, many studies have shown that these two groups of patients are actually taking AREDS vitamins.
In another recent survey of 64 patients with AMD, only 59 percent of them reported that they were taking a vitamin of any kind. Of those patients eligible for AREDS vitamin supplementation, 75 percent reported that no vitamin use had been recommended to them. These studies are dependent on patient responses, which is a big limitation, but the results are still noteworthy.
Patients with bilateral neovascular AMD can at least turn to anti-vascular endothelial growth factor therapies. One recent study, partially sponsored by a then-subsidiary of Bausch + Lomb (which makes supplements), reported that it might be possible. In the small study (40 patients divided into four groups), researchers reported that anti-VEGF therapy in addition to omega-3 fatty acid supplementation may be superior to anti-VEGF therapy alone in terms of lowering intravascular VEGF levels, but added that the effect on CNV levels and vision still need to be elucidated.

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