Purpose: To investigate phenotype characteristics of fellow eyes in patients with early onset of neovascular age-related macular degeneration (NVAMD).
Methods: Patients with new-onset unilateral NVAMD between 50 and 65 years (n = 57, early-onset choroidal neovascularization [CNV] group) or >80 years (n = 47, late-onset CNV group) or with nonneovascular AMD (n = 98, no-CNV group) were included. Fellow eyes in both CNV groups and the eyes with the more severe AMD staging in the no-CNV group were used to evaluate number and size of macular drusen, extramacular drusen (EMD), pigmentary abnormalities, and retinal pigment epithelium (RPE) atrophy on color photographs and hyperreflective dots (HRD) and reticular pseudodrusen (RPD) on spectral-domain optical coherence tomography (SDOCT) scans. Regression analysis was used to compare groups.
Results: Occurrence of >20 macular drusen was more frequent in the early-onset CNV group than the late-onset CNV group (odds ratio [OR] 2.93; P = 0.01) or the no-CNV group (OR 2.17; P = 0.02). Retinal pigment epithelium atrophy, RPD, and HRD appeared less frequently in the early-onset CNV group than in the late-onset CNV group (RPE atrophy: OR 0.11; P = 0.005; RPD: OR 0.04; P = 9.38 × 10⁻¹⁰, HRD: OR 0.30; P = 0.004) and no-CNV group (RPE atrophy: OR 0.12; P = 0.005; RPD: OR 0.40, P = 0.03, HRD: not significant). No differences were detected regarding presence of large drusen, pigmentary abnormalities, and EMD.
Conclusions: A large number of macular drusen in the fellow eye appeared to be characteristic for early onset of NVAMD, whereas RPE atrophy, HRD, and RPD were more frequently present in AMD patients > 80 years. Prospective trials with patients converting to NVAMD are required to further analyze morphologic characteristics for early versus late development of advanced AMD.