AREDS 2 UPDATE – Vitamins For Macular Degeneration
Posted on: May 25, 2013
In 2001, the Age-Related Eye Disease Study (AREDS) led by the National Eye Institute (NEI) established that daily high doses of vitamins (beta-carotene, C, E) and the mineral (zinc and copper) can slow the progression to advanced AMD. While many patients have benefited from the AREDS formulation, beta-carotene use has been linked to a heightened risk of lung cancer in smokers. Also, there are concerns that high doses of zinc may cause minor side effects such as upset stomach.
In 2006 the NEI launched AREDS 2, a five-year study designed to test whether the original formulation could be improved by adding omega-3 fatty acids; adding lutein and zeaxanthin; continuing or removing beta-carotene; or reducing zinc. The study also examined how different combinations of the supplements performed. Omega-3 fatty acids are produced by plants, including algae, and are present in oily fish such as salmon. Lutein and zeaxanthin are carotenoids, a class of plant derived vitamins that includes beta-carotene; both are present in leafy green vegetables and, when consumed, they accumulate in the retina. Prior studies had suggested that diets high in lutein, zeaxanthin, and omega-3 fatty acids protect vision. Before the AREDS2 study finished, manufacturers began marketing supplements based on the study design.
In the original AREDS, participants with AMD taking supplements were 25% less likely to progress to advanced AMD over five years as compared to those who took a placebo. In AREDS2, there was no overall additional benefit from adding omega-3 fatty acids or a 5-to-1 mixture of lutein and zeaxanthin to the formulation. However, the investigators did find some benefit when they analyzed two subgroups of participants; those not given beta-carotene, and those who had very little lutein and zeaxanthin in their diets. These participants had an 18% reduction in developing advanced AMD in 5 years when compared to those who took a formulation with beta-carotene but no lutein or zeaxanthin. The new recommended formula consists of 400 IU Vitamin E, 500 mg Vitamin C, 10 mg Lutein and 2 mg Zeaxanthin, 80 mg Zinc and 2 mg Copper.
Furthermore, similar to the original AREDS findings, the AREDS2 reaffirmed that none of the modified formulations reduced the risk of progression to cataract surgery.
Multiple SCDRC patients participated in the AREDS2. The physicians thank the efforts of our study department and patients who contributed to this landmark clinical trial.