Clinical characteristics and progression of dry age-related macular degeneration in the Japanese population

Abstract

Purpose : To elucidate the clinical characteristics of dry age-related macular degeneration (AMD) and the progression rate of geographic atrophy (GA) using fundus autofluorescence (FAF) in the Japanese population.

Methods : This is a retrospective multicenter noninterventional study. Consecutive patients with GA secondary to AMD were enrolled from six university hospitals in Japan between January 2009 and December 2021. Only eyes with evaluable FAF images were included. The follow-up group consisted of eyes followed for more than 6 months with FAF images. The GA area was measured semiautomatically on FAF images using the Region Finder software. The GA progression rate was calculated by two methods: mm²/year and mm/year using the square root transformation (SQRT) strategy. Simple and multiple linear regression analyses were used to find baseline factors associated with the GA progression rate.

Results : A total of 173 eyes of 173 patients were included in the study. The mean age was 76.8±8.8 (mean±standard deviation) years, and there was a male predominance (109 men, 63.0%). Mean best-corrected visual acuity was 0.34±0.43 (logarithm of the minimum angle of resolution). Thirty-eight eyes (22.0%) were classified as pachychoroid GA. Sixty-two patients (35.8%) had bilateral dry AMD. The mean GA area was 3.06±4.00 mm² (1.44±1.00 mm [SQRT]). Central GA and unifocal GA were identified in 90 (52.0%) and 103 (59.5%) eyes, respectively. Soft drusen and reticular pseudodrusen were detected in 115 (66.5%) and 73 (42.2%) eyes, respectively. The mean subfoveal choroidal thickness was 194.7±105.5 µm. In the follow-up group of 101 eyes of 101 patients (mean follow-up period: 46.2±28.9 months), the progression rate of GA was 1.01±1.09 mm²/year (0.23±0.18 mm/year [SQRT]). In multiple linear regression analysis, the GA area [SQRT] (P=0.007) and reticular pseudodrusen (P=0.009) at baseline were significantly associated with the GA progression rate [SQRT].

Conclusions : This study included the largest number of patients with dry AMD in Japan and elucidated the clinical characteristics and GA progression rate. Male predominance, relatively thicker choroid, lower prevalence of drusen and reticular pseudodrusen, and slower GA progression rate were revealed in the Japanese population, compared with Caucasians. A large sized GA and reticular pseudodrusen were associated with fast GA progression.

This abstract was presented at the 2023 ARVO Annual Meeting, held in New Orleans, LA, April 23-27, 2023.