Geographic atrophy progression and subretinal drusenoid deposits in a real-world Japanese cohort

PURPOSE: To investigate the natural course of geographic atrophy (GA) in Japanese patients, with a focus on factors associated with the change of GA size over time and visual acuity decline. STUDY DESIGN: Retrospective, single-center observational study. METHODS: We reviewed 40 eyes of 40 patients with GA and longitudinal fundus autofluorescence (FAF) imaging. Annual progression rates were calculated as square root-transformed (mm/year). Assessed factors included age, sex, smoking history, diabetes, hypertension, baseline best-corrected visual acuity (BCVA), baseline lesion size, foveal center involvement, choroidal thickness, FAF subtypes, and presence of subretinal drusenoid deposits (SDD). Visual outcomes were assessed as change in BCVA (ΔBCVA, logarithm of the minimum angle of resolution (logMAR)). RESULTS: Median age was 75.5 years; 50% of eyes had SDD. The median annual GA progression rate was 0.16 mm/year in square root units. Baseline GA area and the presence of SDD were independent predictors of GA progression (β = -0.0837, p = 0.015; β = +0.3064, p = 0.009, respectively). In multivariable analysis, baseline GA area also remained a significant predictor of visual deterioration (β = +0.1369, p = 0.002). When stratified by FAF patterns, there was significant worsening of BCVA in the Diffuse (p = 0.0027) and Banded (p = 0.0117) subtypes, whereas the None and Other subtypes did not show significant changes in BCVA over one year. CONCLUSIONS: SDD was identified as a significant risk factor for GA progression in Japanese patients. These findings improve understanding of natural history of GA in Japanese population and may inform risk stratification.