Age-related Eye Disease Study 2: perspectives, recommendations, and unanswered questions.

PURPOSE OF REVIEW: This review provides a perspective on the Age-related Eye Disease Study 2 (AREDS2) including a summary of the goals and rationale of the study, major findings, subsequent management recommendations, and questions that remain to be answered.

RECENT FINDINGS: The primary goal of the AREDS2 was to evaluate the efficacy and safety of lutein plus zeaxanthin and/or omega-3 long-chain polyunsaturated acid supplementation in reducing the risk of developing advanced age-related macular degeneration (AMD). AREDS2 also investigated the effects of omitting β-carotene and reducing the concentration of zinc from the original AREDS formulation. Although primary analysis from the AREDS2 did not reveal a benefit of daily supplementation with lutein/zeaxanthin on AMD progression, secondary exploratory analyses suggested that lutein/zeaxanthin were helpful in reducing this risk. Comparison of low-dose to higher-dose zinc showed no significant benefit.

SUMMARY: The overall evidence on the beneficial and adverse effects from AREDS2 and other studies suggests that lutein/zeaxanthin could be more appropriate than β-carotene in AREDS-type supplements. Questions remain regarding the AREDS2 study results such as: whether the findings are generalizable to the population as a whole, what is the long-term safety profile of lutein/zeaxanthin supplementation, should other carotenoids be included in AREDS-type supplements, and at what optimal doses?