Correlation of Change in Central Subfield Thickness and Change in Visual Acuity in Neovascular AMD: Post Hoc Analysis of VIEW 1 and 2
Onnisa Nanegrungsunk, Sophie Z. Gu, Susan B. Bressler, Weiming Du, Fouad Amer, Hadi Moini, Neil M. Bressler
Abstract
PURPOSE: Determine correlation between change in central subfield thickness (CST) and change in best-corrected visual acuity (BCVA) in neovascular age-related macular degeneration receiving anti-vascular endothelial growth factor agents. DESIGN: A post hoc analysis of VIEW 1 and 2 randomized clinical trials. METHODS: This analysis included participants randomized to ranibizumab 0.5 mg every 4 weeks (Rq4), intravitreal aflibercept injection 2 mg every 4 weeks (2q4), and intravitreal aflibercept injection 2 mg every 8 weeks after 3 monthly doses (2q8) to week 52, followed by capped as-needed (at least every 12 weeks) dosing to week 96. Relationship between changes in CST and BCVA was determined using Pearson correlation coefficient. RESULTS: Of 1815 eyes, 595 were assigned to the Rq4, 613 to 2q4, and 607 to 2q8 arms. Correlations (95% confidence intervals [CI]) at weeks 12, 52, and 96 were -0.08 (95% CI, -0.17 to 0.00), -0.05 (95% CI, -0.14 to 0.04), and -0.15 (95% CI, -0.24 to -0.06) for Rq4; -0.13 (95% CI, -0.21 to -0.04), -0.06 (95% CI, -0.14 to 0.03) and -0.04 (95% CI, -0.13 to 0.05) for 2q4, and -0.04 (95% CI, -0.12 to 0.05), -0.01 (95% CI, -0.09 to 0.08), and -0.01 (95% CI, -0.10 to 0.09) for 2q8. Linear regression analysis adjusted for relevant baseline factors showed CST changes accounted for 11% of BCVA changes. Every 100 μm decrease in CST was associated with a 0.3 letter decrease (P = .25) at week 52 and a 0.14 letter decrease (P = .69) at week 96. CONCLUSIONS: Weak or no correlation was found between changes in CST and BCVA with either agent or regimen, suggesting changes in CST should not be used as a surrogate for visual acuity outcomes in neovascular age-related macular degeneration.