Age-Related Eye Disease Study (AREDS) Follow-Up

Overview

This study is a 5-year extension of the AREDS protocol, in which investigators followed the natural course of age-related macular degeneration (AMD) and cataracts. Participants in the former AREDS protocol are eligible for this study. Participants have a complete eye examination once a year and are contacted at least once a year between visits to check on their status. The eye examination includes measurement of visual acuity (vision chart test) and examination of the inside of the eye after the pupils have been dilated with eye drops. Photographs of the inside of the eye may be taken using a special camera that flashes a bright light in the eye. A blood sample may be obtained to test for cholesterol level and genes related to inflammation.

The Age-Related Eye Disease Study (AREDS) Follow-Up protocol allows us to continue with the follow-up of participants who were enrolled in the clinical trial of antioxidant vitamins and zinc. The AREDS study was designed in the beginning to determine the clinical course and prognosis of age-related macular degeneration (AMD) and cataracts.1 In addition, AREDS evaluated the possible risk factors associated with the development of AMD and cataracts; the nutritional risk factors were evaluated and published in October 2001. Study results showed that antioxidant vitamins and zinc therapy reduced the risk of developing advanced AMD in participants with intermediate and greater risk of developing AMD (categories 3 and 4) by 25%. The risk of vision loss of three lines or more on the logarithmic visual acuity charts was also reduced by 19% for these participants. For those who developed AMD, their risk of vision loss was reduced by 25%. Antioxidants and zinc are now recommended for participants who have an intermediate risk of developing advanced AMD. Upon completion of the AREDS clinical trial in September 2001, participants were invited for follow-up for an additional five years to collect further data on the natural course of both AMD and cataracts. Although the multi-center trial was complete in December 2005, we wish to continue to follow-up on these participants at the NEI on an annual basis for a minimum of five years from the date of enrollment in this study to collect additional data. Although results from AREDS on the relationship of lutein/zeaxanthin and omega-3 long-chain polyunsaturated fatty acid (LCPUFA) intake with advanced AMD were informative, the non-experimental sampling (observational) design limited our strength of inference. AREDS2, a multi-center Phase III randomized clinical trial, was designed to assess the effects of oral supplementation of high doses of macular xanthophylls (lutein and zeaxanthin) and/or omega-3 LCPUFAs as a treatment for AMD, cataract, and moderate vision loss. In addition to this objective, the study provided information on the clinical course, prognosis, and risk factors for development and progression of both AMD and cataract. Other study goals included the evaluation of eliminating beta-carotene and/or reducing zinc in the original AREDS formulation on the progression and development of AMD. AREDS2 also sought to validate the fundus photographic AMD scale developed from AREDS. Participants who completed AREDS2 are invited for follow-up on an annual basis for at least five years from the date of enrollment in this study to collect additional data.