Abstract
Abstract: :
Purpose:To evaluate the effect of high-dose antioxidant and/or zinc supplements on the development of drusen in AREDS. Methods:Participants in AREDS were randomly assigned to receive daily tablets containing (1) antioxidants (vitamin C, vitamin E, and beta carotene); (2) zinc as zinc oxide and copper as cupric oxide; (3) antioxidants plus zinc; or (4) placebo. To assess change in drusen size (development of large drusen OU or of advanced AMD in at least one eye), we identified for analysis 1,805 AREDS participants without advanced AMD in either eye or large drusen OU at baseline. To assess change in drusen area (progression of drusen area to at least 1/2 disc area (DA) in at least one eye), we identified 1,790 AREDS participants without advanced AMD and with drusen area less than 1/16 DA at baseline. Drusen progression in size and area was graded from fundus photographs. Cox proportional hazards analysis was used to evaluate the association. Results:The 5-year progression in drusen size, to large drusen OU or advanced AMD in at least one eye, was 18% for placebo, 20% for antioxidants alone, 18% for zinc alone and 21% for antioxidants plus zinc. The AMD category adjusted risk ratios for progression were 1.00 for antioxidants alone, 0.93 for zinc alone, and 1.07 for antioxidants plus zinc. The 5-year progression in drusen area, to increased drusen area in at least one eye, was 5% for placebo, 4% for antioxidants alone, 5% for zinc alone and 5% for antioxidants and zinc. The AMD category adjusted risk ratios were 0.69 for antioxidants alone, 0.93 for zinc alone, and 0.94 for antioxidants and zinc. Analyses adjusted for age, sex, race, and baseline smoking status did not materially alter the size or direction of these risk ratio estimates. None of the risk ratios were statistically significant (P≷.05). Conclusion:Use of high-dose antioxidant and/or zinc supplementation in AREDS did not have an effect on change in drusen size or area.
Keywords: 357 clinical (human) or epidemiologic studies: treatment/prevention assessment/controlled clinical trials • 492 nutritional factors • 391 drusen