In a recent data analysis, researchers at the National Institutes of Health (NIH) discovered that daily intake of a supplement enriched with antioxidant vitamins and minerals can decelerate the progression of late-stage dry age-related macular degeneration (AMD). This finding suggests a potential for individuals in the late stages of the disease to maintain their central vision. The study involved a re-examination of the original retinal scans from participants in the Age-Related Eye Diseases Studies (AREDS and AREDS2), revealing that for those with late-stage dry AMD, the antioxidant supplements reduced the growth of geographic atrophy areas towards the central foveal region of the retina. The results were published in the journal Ophthalmology.
Tiarnan Keenan, M.D., Ph.D., from the NIH’s National Eye Institute (NEI) and lead author of the study, highlighted the established benefits of AREDS2 supplements in slowing the progression from intermediate to late AMD. He explained that the new analysis demonstrates that these supplements are also beneficial in managing disease progression in patients with late-stage dry AMD, endorsing the continued use of AREDS2 supplements for individuals with this condition.
The analysis involved a detailed review of the initial retinal scans of participants from the AREDS (comprising 318 participants with 392 eyes) and AREDS2 (involving 891 participants with 1210 eyes) trials who had developed dry AMD. Researchers calculated the location and growth rate of their geographic atrophy regions. While the supplements showed minimal benefit for those with geographic atrophy in the central vision, they significantly slowed the atrophy expansion towards the fovea by about 55% over three years for most participants whose atrophy was situated farther from the fovea.
Typically, in the early and intermediate stages of AMD, the retina accumulates small yellow deposits known as drusen, composed of fatty proteins. As the disease advances to the late stage, it can lead to the formation of leaky blood vessels (“wet” AMD) or the loss of light-sensitive cells in the retina (“dry” AMD). Over time, the resulting geographic atrophy gradually enlarges, leading to progressive central vision loss.
The original AREDS trial demonstrated that a supplement formula containing antioxidants (vitamin C, E, and beta-carotene), zinc, and copper could slow the progression from intermediate to late-stage AMD. The subsequent AREDS2 trial improved the formula’s effectiveness and safety by replacing beta-carotene with the antioxidants lutein and zeaxanthin. However, these early findings did not consider a phenomenon known as “foveal sparing” in the dry form of late AMD. Although all retinal regions are light-sensitive, the fovea provides the sharpest central vision. Many individuals with dry AMD initially develop geographic atrophy outside this foveal region and only experience central vision loss when the atrophy reaches the foveal area.
Keenan emphasized the critical nature of high acuity central vision for activities such as reading and driving. He pointed out that antioxidant supplementation could offer a simple yet effective way to slow central vision loss, even in late-stage dry AMD. With plans to validate these findings further through a dedicated clinical trial soon, there is hope for new therapeutic options to help those affected by this challenging condition.
More information: Tiarnan D.L. Keenan et al, Oral Antioxidant and Lutein/Zeaxanthin Supplements Slow Geographic Atrophy Progression to the Fovea in Age-Related Macular Degeneration, Ophthalmology. DOI: 10.1016/j.ophtha.2024.07.014
Journal information: Ophthalmology Provided by NIH / National Eye Institute
