Transition from intermediate to late AMD and associated changes in vision by two years in a multicentre cohort study in Europe- INTERCEPT-AMD Report 3.

BACKGROUND/OBJECTIVES: The aim was to evaluate the incidence of late AMD in eyes with intermediate AMD (iAMD) over two years. SUBJECTS/METHODS: In this multicentre cohort study, participants with iAMD were classified as: (i) iAMD without incomplete retinal pigment epithelium or outer retinal atrophy (iRORA) or subretinal drusenoid deposits (SDD); (ii) iAMD with SDD with no iRORA; (iii) iAMD with iRORA with no SDD and (iv) iAMD with iRORA and SDD. Factors associated with the incidence of late AMD were analysed using an interval-censored Weibull parametric proportional hazards model. RESULTS: 983 eyes from 805 participants were analysed. Model-based cumulative incidence at nominal 2 years was 13.1% (95% CI 10.8-15.6%) for late AMD, 7.6% (95% CI 5.9-9.3%) for nAMD as the cause and 5.5% (95% CI 4.1-7.3%) for cRORA as the cause. Participants aged 75-84 (adjusted HR [aHR] 1.66, 95% CI 1.13-2.46; P = 0.01), 85 years+ (aHR 2.48, 95% CI 1.49-4.15; P = 0.001), presence of iRORA (aHR 1.50, 95% CI 1.05-2.16; P = 0.03), fellow-eye nAMD (aHR 3.23, 95% CI 2.04-5.12; P < 0.001) and BRVA 70-79 (vs 80 or better ETDRS letters: aHR 1.65, 95% CI 1.09-2.49; P = 0.02) had increased hazard of late AMD. Eyes that transitioned to neovascular AMD (nAMD) by 2 years (within tolerance window) displayed the greatest loss in BRVA compared to other phenotypes (-6.01 letters, SD 11.35). CONCLUSIONS: Approximately 13% of eyes with iAMD progressed to late AMD within 2 years. Eyes that transitioned to nAMD experienced the greatest loss in BRVA.