Objective: To determine the baseline predictors of visual acuity (VA) outcomes 1 year after treatment with ranibizumab or bevacizumab for neovascular age-related macular degeneration (AMD).
Design: Cohort study within the Comparison of Age-related Macular Degeneration Treatments Trials (CATT).
Participants: A total of 1105 participants with neovascular AMD, baseline VA 20/25 to 20/320, and VA measured at 1 year.
Methods: Participants were randomly assigned to ranibizumab or bevacizumab on a monthly or as-needed schedule. Masked readers evaluated fundus morphology and features on optical coherence tomography (OCT). Visual acuity was measured using electronic VA testing. Independent predictors were identified using regression techniques.
Main outcome measures: The VA score, VA score change from baseline, and ≥3-line gain at 1 year.
Results: At 1 year, the mean VA score was 68 letters, mean improvement from baseline was 7 letters, and 28% of participants gained ≥3 lines. Older age, larger area of choroidal neovascularization (CNV), and elevation of retinal pigment epithelium (RPE) were associated with worse VA (all P<0.005), less gain in VA (all P<0.02), and a lower proportion gaining ≥3 lines (all P<0.04). Better baseline VA was associated with better VA at 1 year, less gain in VA, and a lower proportion gaining ≥3 lines (all P<0.0001). Predominantly or minimally classic lesions were associated with worse VA than occult lesions (66 vs. 69 letters; P=0.0003). Retinal angiomatous proliferans (RAP) lesions were associated with more gain in VA (10 vs. 7 letters; P=0.03) and a higher proportion gaining ≥3 lines (odds ratio, 1.9; 95% confidence interval, 1.2-3.1). Geographic atrophy (GA) was associated with worse VA (64 vs. 68 letters; P=0.02). Eyes with total foveal thickness in the second quartile (325-425 μm) had the best VA (P=0.01) and were most likely to gain ≥3 lines (P=0.004). Predictors did not vary by treatment group.
Conclusions: For all treatment groups, older age, better baseline VA, larger CNV area, predominantly or minimally classic lesion, absence of RAP lesion, presence of GA, greater total fovea thickness, and RPE elevation on optical coherence tomography were independently associated with less improvement in VA at 1 year.
Financial disclosure(s): The author(s) have no proprietary or commercial interest in any materials discussed in this article.
Copyright © 2013 American Academy of Ophthalmology. Published by Elsevier Inc. All rights reserved.