Abstract
Abstract: :
Purpose: To identify risk factors for vision loss in patients with age–related exudative macular degeneration, baseline ocular characteristics were analyzed in the data set of a completed one–year study. Methods: A phase I/II trial of an oral angiogenesis inhibitor was conducted in patients with subfoveal choroidal new vessels (CNV). Eligibility guidelines required that lesions be 6 disc areas or less with some classic CNV component. Analysis of the study outcome measures showed no treatment effect of the agent on vision or lesion morphology at 3, 6 and 12 months. Multiple regression analysis was applied to the data set (n=148 eyes) to test the effect of baseline visual acuity, lesion size, and CNV subtype on moderate visual loss (decline of 15 or more letters on the ETDRS chart). Results: Despite modeling for the effects of lesion size and subtype, baseline visual acuity remained the most important determinant of visual outcome at each time period. Conversely, baseline lesion size or lesion type had no discernable effect. The 30 eyes with baseline visual acuity (VA) of less than 49 ETDRS letters (20/200) had lower risk of moderate vision loss at one year (33.3%) compared to the 118 eyes with VA better than 49 letters (72.9%, p=0.001 for the comparison by Chi–square test). Conclusions: In this study of exudative macular degeneration, baseline lesion size or CNV subtype were less important predictors of vision outcome at one year than baseline visual acuity. Clinical trials with visual acuity as the primary outcome may consider excluding patients with acuity less than 49 letters (20/200), since these subjects are likely to have a low event rate.
Keywords: age–related macular degeneration • choroid: neovascularization • clinical (human) or epidemiologic studies: risk factor assessment