Predictors of visual response to intravitreal bevacizumab for treatment of neovascular age-related macular degeneration

Abstract

Purpose. To identify the predictors of visual response to the bevacizumab treatment of neovascular age-related macular degeneration (AMD). Design. A cohort study within the Neovascular AMD Treatment Trial Using Bevacizumab (NATTB). Methods. This was a multicenter trial including 144 participants from the NATTB study. Visual outcomes measured by change in visual acuity (VA) score, proportion gaining ≥15 letters, and change in central retinal thickness (CRT) were compared among groups according to the baseline, demographic, and ocular characteristics and genotypes. Results. Mean change in the VA score was 9.2 ± 2.3 SD letters with a total of 46 participants (31.9%) gaining ≥15 letters. Change in median CRT was -81.5 μ m. Younger age, lower baseline VA score, shorter duration of neovascular AMD, and TT genotype in rs10490924 were significantly associated with greater VA score improvement (P = 0.028, P < 0.001, P = 0.02, and P = 0.039, resp.). Lower baseline VA score and TT genotype in rs10490924 were significantly associated with a higher likelihood of gaining ≥15 letters (P = 0.028, and P = 0.021, resp.). Conclusions. Baseline VA and genotype of rs10490924 were both important predictors for visual response to bevacizumab at 6 months. This trial is registered with the Registration no. NCT01306591.

Figure 1

(a) Association of baseline visual acuity (VA) score with VA score change at 6 months. Baseline VA score was significantly associated with VA score change at 6 months (P = 0.015). *P = 0.036 (the first group was the reference). (b) Association of duration of neovascular age-related macular degeneration (AMD) with VA score change at 6 months. Duration of neovascular AMD was significantly associated with VA score change at 6 months (P = 0.005). *P = 0.005; ^† P = 0.007; ^‡ P = 0.001 (the first group was the reference).

Figure 2

(a) Association of baseline visual acuity (VA) score with proportion of ≥15 letters gaining from baseline at 6 months. Baseline VA score was significantly associated with proportion of ≥15 letters gaining from baseline at 6 months (P = 0.005). *P = 0.015 (the first group was the reference). (b) Association of duration of neovascular age-related macular degeneration (AMD) with proportion of ≥15 letters gaining from baseline at 6 months. Duration of neovascular AMD was significantly associated with proportion of ≥15 letters gaining from baseline at 6 months (P = 0.021). *P = 0.009 (the first group was the reference).