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The Age-Related Eye Disease Study (AREDS) was initially conceived as a long-term multicenter, prospective study of the clinical course of age-related macular degeneration (AMD) and age-related cataract. Data on progression rates and risk factors from the study will increase understanding of the clinical course of both conditions, generate hypotheses about etiology, and aid in the design of clinical trials of potential interventions. In addition to collecting natural history data, AREDS includes a clinical trial of high-dose vitamin and mineral supplements for AMD and a clinical trial of high-dose vitamin supplements for cataract. The clinical trials were initiated largely because of the widespread public use in the United States of commercially available pharmacologic doses of vitamins and minerals to treat these two eye conditions and the absence of definitive studies on the safety and efficacy of their use. Important design issues for the clinical trials include: defining cataract and AMD, estimating event rates, determining the type and dosage of vitamins and minerals to be tested for each condition, and identifying the parameters necessary for monitoring safety and efficacy. This paper describes the AREDS design, including the study rationale and operational structure, and the approach adopted to combine, for two diseases, clinical trials with a natural history study. Control Clin Trials 1999;20:573–600

To study the improvement in visual acuity over time in patients with central scotomas.In a prospective natural history study of geographic atrophy (GA) from age-related macular degeneration (ARMD) with annual follow-up, 36 patients with bilateral GA completed 3 years of follow-up. Protocol visual acuity (VA) measurements were performed. Scanning laser ophthalmoscopy (SLO) was performed, and the areas of GA were measured from fundus photographs.Six eyes of six patients with VA ranging from 20/80 to 20/500 had a VA improvement of two or more lines (mean, 3.2 lines). This was found only in the worse-seeing eyes of the patients and was contemporaneous with the deterioration in VA of the better-seeing eyes. Four of six eyes that improved in acuity had an improvement in the ability to find and hold the fixation target in an area of seeing retina, as assessed by SLO at follow-up, and a fifth eye changed from one fixation site that had little functional retina to another site.Spontaneous improvement in VA in eyes with bilateral GA and central scotomas may occur. It appears to be related to deterioration in VA of the better-seeing fellow eye and is associated with improvement of fixation in the worse-seeing eye. The worse-seeing eye of a patient with bilateral ARMD may have the potential for better vision than measured VA indicates. This finding may have implications for the choice of patients in treatment trials, for interpretation of long-term results, and for planning and assessment of low vision intervention.

Geographic atrophy is the advanced form of atrophic age-related macular degeneration. It is present in 3.5% of people age 75 and over in the United States. It progresses gradually over time, often sparing the fovea until late in the course of the disease. Forty to fifty percent of eyes with geographic atrophy and good visual acuity at baseline lose three or more lines of acuity by two years and 27% become worse than 20/200 by four years. This article discusses the information known about age-related geographic atrophy at the present time.

There is a lack of knowledge about why and how atrophy spreads over time Choroidal neovascularisation (CNV) and geographic atrophy (GA) of the retinal pigment epithelium (RPE) are the two forms of advanced age related macular degeneration (AMD), the major cause of severe central visual loss in white people aged 60 and older.1 Clinical and histopathological studies in the 1970s laid the foundation for our understanding that CNV and GA are both part of the same basic disease process.2–4 The two conditions share similar ophthalmoscopic risk factors for their development. Both are more likely in eyes with large drusen or many intermediate drusen, and in eyes with pigmentary abnormality. There may be overlap of the two conditions within patients and sometimes within a single eye. Patients may have CNV in one eye and GA in the fellow eye. They may have GA in an eye and then develop CNV in that eye.5–7 They may have CNV in an eye, which on involution takes on the appearance of GA.8,9,10 They may have an evanescent form of CNV which leaves what appears as “pure” GA in its wake.7,11 Histopathologically, there is often CNV present in cases that have been diagnosed as having “pure” GA.3,12 In this issue of the BJO , Sarks and co-authors (p 442) report their findings, in 20 eyes of 18 patients, of the development of progressive atrophy of the RPE around disciform scars from …