Antioxidant vitamin and mineral supplements for slowing the progression of age-related macular degeneration.
Level 1 - systematic review of randomized trials
Systematic review of randomized controlled trials
PubMed 37702300 · doi:10.1002/14651858.CD000254.pub5
What was done
This Cochrane systematic review assessed the effects of antioxidant vitamin and mineral supplementation on the progression of age-related macular degeneration (AMD). Searches were updated through November 2022. The authors included 26 randomized controlled trials enrolling 11,952 participants aged 65 to 75 years (56% women) across the USA, Europe, China, and Australia comparing multivitamins, lutein/zeaxanthin, vitamin E, or zinc to placebo or no intervention.
What was found
Antioxidant multivitamin supplementation (mainly AREDS formulation) reduced progression to late AMD (OR 0.72, 95% CI 0.58 to 0.90; 3 studies, 2445 participants; moderate certainty), corresponding to 4 fewer cases per 1,000 in early AMD and 78 fewer per 1,000 in intermediate AMD. Multivitamins also reduced neovascular AMD (OR 0.62, 95% CI 0.47 to 0.82) and vision loss of 3 or more lines (OR 0.77, 95% CI 0.62 to 0.96). Zinc alone reduced progression to late AMD (OR 0.83, 95% CI 0.70 to 0.98; 3 studies, 3790 participants) and neovascular AMD (OR 0.76, 95% CI 0.62 to 0.93). Lutein/zeaxanthin showed small or uncertain effects compared with control on late AMD (RR 0.94, 95% CI 0.87 to 1.01; low certainty), though substituting lutein/zeaxanthin for beta-carotene yielded an HR of 0.82 (95% CI 0.69 to 0.96) for late AMD. Vitamin E alone showed no clear effect (RR 1.36, 95% CI 0.31 to 6.05; very low certainty). Beta-carotene was associated with increased lung cancer risk in former smokers.
Why it matters
This review reinforces that combination antioxidant and zinc supplementation meaningfully delays progression to late-stage disease and visual loss specifically for patients with intermediate AMD, while offering negligible absolute benefit for early-stage disease.
Limits
The evidence base is heavily driven by two large US trials (AREDS and AREDS2), with few independent large-scale replications. Most other included trials had small sample sizes, short follow-up (some as brief as six months), and lacked power to detect rare adverse events or quality-of-life differences.
Cited by
- context Randomized controlled trials show that lutein and zeaxanthin accumulate in the eye and can help prevent age-related macular degeneration.