To print: Select File and then Print from your browser's menu --------------------------------------------------------------------------------------- Title: Eye Disease Study Shows Limits to Usefulness of Antioxidants and Other Supplements to Prevent Macular Degeneration: Presented at AAO URL: http://www.pslgroup.com/dg/2174EA.htm Doctor's Guide November 16, 2007
By Earl R. Nichols NEW ORLEANS, LA -- November 16, 2007 -- Smoking is one of the strongest risk factors for developing age-related macular degeneration (AMD), but people who smoke should not begin taking the Age-Related Eye Disease Study (AREDS) formulation of vitamins and antioxidants, the lead investigator on the AREDS trial says. In a presentation at the Retina Subspecialty Day sessions of the American Academy of Ophthalmology (AAO), Emily Chew, MD, Deputy Director, Division of Epidemiology and Clinical Research, National Eye Institute, Bethesda, Maryland, United States, said patients who smoke and take beta carotene supplements have an increased risk of developing lung cancer. In her presentation, Dr. Chew outlined which patients should and should not take AREDS supplements. The AREDS study enrolled more than 4,700 patients who received supplements of vitamin C and E, beta carotene, zinc and copper and were followed for 6.3 years. The results of the study showed that while there was a protective benefit for patients with large bilateral macular drusen and those with advanced AMD in one eye, there was no protective benefit for patients with mild and moderate AMD. The supplements did not prevent progression to severe AMD in these patients. Dr. Chew pointed out, however, that the risk of developing AMD in these patients is "exceedingly low," and therefore, it is unlikely that they would progress to severe AMD (Arch Ophthalmol 2001; 119 (10): 1417-36). According to Dr. Chew, patients who still smoke, or quit smoking within the past year should avoid the supplements because of the increased risk of cancer. Nor should the offspring of patients with AMD take the supplements, unless they too have AMD in one eye, or large bilateral drusen. But for most individuals, the benefits of the supplements seem to outweigh any risks. Recently, a meta-analysis of 68 trials, including AREDS, reported no significant impact associated with a wide variety of antioxidant supplements (relative risk [RR] = 1.02) (JAMA 2007; 297 (8): 842-57). Also, a sub-group analysis of patients from the AREDS trials who were followed for a total of 10.5 years found that 1,057 patients (22%) died, but that there was no association between the use of zinc and other antioxidants, and mortality (RR = 0.88 95% confidence interval [CI], 0.73 - 1.07). Intervention with zinc alone (80 mg/day) had a protective effect against mortality (RR 0.83 95% CI, 0.73 - 0.95). The clinical importance of this finding is still unknown since this subgroup analysis involved only 904 patients. More study is needed, Dr. Chew said (Arch Ophthalmol 2004; 122 (5): 716-26). Furthermore, she said, a recently published analysis of AREDS data also showed that patients with the highest intake versus the lowest intake of lutein/zeaxanthin have lower risk of geographic atrophy (odds ratio [OR] = 0.45), neovascular AMD (OR=0.65) and large drusen (OR = 0.73) compared with individuals in the lowest quintile compared with those in the highest intake of these supplements (Arch Ophthalmology 2007; 125 (9): 1225-32). Dr. Chew concluded that the public health impact of this supplementation regimen could prevent 300,000 people over the next 5 years from either developing advanced macular degeneration or experiencing significant loss of vision as a result of progressive disease. [Presentation title: Antioxidants, Minerals, and Nutrition in AMD. Retina Subspecialty Day] --------------------------------------------------------------------------------------------- Copyright © 1999 P\S\L Consulting Group Inc. All rights reserved. Republication or redistribution of P\S\L content is expressly prohibited without the prior written consent of P\S\L. P\S\L shall not be liable for any errors, omissions or delays in this content or any other content on its sites, newsletters or other publications, nor for any decisions or actions taken in reliance on such content. --------------------------------------------------------------------------------------------- This news story was printed from *Doctor's Guide to the Internet* located at http://www.docguide.com --------------------------------------------------------------------------------------- Return to News Story Page This site is maintained by webmaster@pslgroup.com Please contact us with any comments, problems or bugs. All contents Copyright (c) 1998 P\S\L Consulting Group Inc. All rights reserved.