I agree that ophthalmologists should be alert to special considerationswhen advising their patients regarding therapy, including high-dose vitamintherapy. The authors of AREDS1 concludedthat persons identified at risk of developing advanced age-related maculardegeneration who do not have contraindications such as smoking should considertaking a supplement of antioxidants plus zinc such as that used in AREDS.With regard to the risk of osteoporosis and the AREDS formulation, it is importantto note that the AREDS supplement included 15 mg of beta carotene, not vitaminA in retinol form. The association of osteoporosis has been found with serumretinol but not serum beta carotene.2 Weknow of no large studies of beta carotene use that show an association withosteoporosis. Findings of various complications with high-dose vitamins orminerals underscore the need to assess risks and benefits whenever prescribingany new treatment. Results from AREDS demonstrated that the risk of progressingto advanced age-related macular degeneration in 5 years was 25% lower in patientsat risk who received the AREDS formulation.1 Thepotential public health effect in the United States is not trivial.3 Balancing the potential benefit in the high-riskgroup identified in AREDS can be difficult, but for most persons with drusenat less than high-risk level, perhaps the strategy of careful follow-up withinitiation of high-dose supplements if their drusen advance is good.
Frederick L. Ferris, Roy C. Milton. Special Considerations in the Guidelines for High-Dose Vitamin Supplementationin Patients With Age-Related Macular Degeneration—Reply. Arch Ophthalmol. 2004;122(4):662–663. doi:10.1001/archopht.122.4.662-b