In the news: AREDS2 Supplement Reported to Slow GA Expansion in Late AMD

Data Supports AREDS2 Supplement Use in Advanced Dry AMD

The original Age-Related Eye Disease Study (AREDS) showed that supplementation with high dose antioxidants and zinc decreased the risk of progression from intermediate to advanced AMD.

AREDS2 showed that replacing beta carotene with lutein and zeaxanthin reduced safety risks and improved effectiveness in slowing the progression from intermediate to late AMD.

Neither study, however, further assessed the effectiveness of the formulations in people with advanced to late-stage disease. Is it possible that AREDS formulas also slow progression of the disease in those with late dry AMD (geographic atrophy or GA)?

Investigators from the AREDS and AREDS2 Research Groups asked just that question by conducting a post-hoc analysis of these two studies(1) .

The main findings show that: •     AREDS supplements slowed progression by 55% over 3 years for those who developed GA distant from the fovea; •     the AREDS2 formula with lutein/zeaxanthin, but not the AREDS formula, also slowed the decline in visual acuity; •     neither supplement slowed degeneration in more advanced cases where central vision was already affected.

The new analysis looked at the rate of expansion and the location of GA in 392 eyes of AREDS participants and 1,210 eyes of AREDS2 participants with GA. Each endpoint was measured by color fundus photographs taken annually over 3 years.

In most cases of GA, lesions emerge away from the central macula and gradually expand, usually in all directions, to involve most of the macula. The main aim of this study was to measure GA-based area and proximity-based progression rates in the eyes of AREDS and AREDS2 patients according to their treatment assignments, to determine whether oral antioxidants, zinc, lutein/zeaxanthin or fatty acids slow GA progression.

The secondary aim was to analyze rates of change in visual acuity, also according to treatment assignment.

In eyes with non-central GA, both the AREDS supplement and (in AREDS2) supplementation with lutein and zeaxanthin led to slower GA progression towards the central macula. Randomization to beta-carotene in AREDS2 did not alter the GA progression rate.

While the analysis showed slower rates of expansion with AREDS and AREDS2, the supplements did not alter area-based progression.

The authors point out that GA progression into the central macular area is substantially lower than GA advancement into the more peripheral macula. This phenomenon is known as foveal sparing – a phenomenon whose underlying mechanism(s) is not known.

Results of the analyses suggest that vitamin C, vitamin E and lutein/zeaxanthin may contribution to and augment the known phenomenon of foveal sparing from GA in AMD, state the authors.

“These findings support the continued use of AREDS2 supplements by people with late dry AMD”, according to the study’s lead author, Tiarnan Keenan, M.D., Ph.D. of NIH’s National Eye Institute(2) . Dr. Keenan indicates that ““we plan to confirm these findings in a dedicated clinical trial in the near future.”

References

1. Keenan TDL, et al. for the AREDS and AREDS2 Research Groups. Oral antioxidant and lutein/zeaxanthin supplements slow geographic atrophy progression to the fovea in age-related macular degeneration. Ophthalmol. July 16, 2024. https://doi.org/10.1016/j.ophtha.2024.07.014
2. NIH News release. https://www.nih.gov/news. July 16, 2024.