Predicting vision gains with anti-VEGF therapy in neovascular age-related macular degeneration patients by using low-luminance vision

Abstract

Background/aims: To evaluate baseline low-luminance visual acuity (LLVA) as a predictor of visual acuity improvement in patients with neovascular (wet) agerelated macular degeneration (wAMD) receiving antivascular endothelial growth factor A (anti-VEGF) therapy. Methods: In the HARBOR trial, 1084 treatment-naïve patients ≥50 years of age with subfoveal wAMD received intravitreal ranibizumab 0.5 or 2.0 mg monthly or as needed. To measure LLVA, patients read a normally illuminated ETDRS (Early Treatment Diabetic Retinopathy Study) chart with a neutral density filter placed in front of the study eye. Patients were assigned into quartiles based on the magnitude of the difference between best corrected visual acuity under optimal luminance (BCVA) and LLVA (BCVA-LLVA gap). The association between mean change in BCVA from baseline and BCVA-LLVA gap at baseline was analysed using a general linear model. Results: A smaller baseline BCVA-LLVA gap predicted significantly higher BCVA gains over 24 months (p<0.0001 at each month; Pearson correlation), even after controlling for baseline BCVA or stratifying by treatment arm. Patients in the smallest baseline BCVA-LLVA gap quartile gained an average of +13.4 letters compared with +2.4 letters for patients in the widest baseline BCVA-LLVA gap quartile. At months 12 and 24, the smallest baseline BCVA-LLVA gap quartile had the highest proportion of ≥15-≥30-letter gain, and the widest baseline BCVA-LLVA gap quartile had the highest proportion of ≥15-/≥30-letter loss (p<0.0001; Fisher's exact test). Conclusions: The baseline BCVA-LLVA gap is a significant predictor of visual acuity response to antiVEGF treatment in patients with wAMD. Trial registration number: NCT00891735; Post results.