Long-Term Natural History of Treatment-Naïve Geographic Atrophy in Age-Related Macular Degeneration

Abstract

Purpose : To evaluate the long-term fundus-autofluorescence based growth rate of treatment-naïve patients with geographic atrophy (GA, cRORA) in age-related macular degeneration (AMD).

Methods : Patient charts with GA in AMD were identified resulting in 249 screened eyes of 167 patients. Inclusion criteria as in recent studies on GA were applied: GA baseline (BL) area on FAF >=2.5mm² and <=17.5mm² with a follow-up (FU) period >=1 year. Exclusion criteria were: exudation macular neovascularisation, other macular pathologies.

Results : In total, 104 eyes (75 patients) were enrolled. Three subgroup-pairs were compared: Fovea-involving vs. fovea-sparing, multifocal vs. unifocal and bilateral vs. unilateral. The total median FU period was 29 months (min-max: 12-109). The mean corrected visual acuity (CVA) at BL was fovea-involving 38.2±17.1; fovea-sparing 65.1±16.8 ETDRS letters. At the last FU fovea-involving: 33.1±13.6 (D-5.1); fovea-sparing: 54.7±21.3 (D-10.4) ETDRS letters. Of the initially 40 fovea-sparing converted 6 eyes (15%) to a foveal involvement. The mean GA lesion area at BL was fovea-involving 8.29±4.48mm²; fovea-sparing 7.22±4.89mm² and multifocal 6.61±4.74mm²; unifocal 8.11±4.62mm² and bilateral 12.87 ±6.56mm²; unilateral 9.27 ±6.44mm². The GA area at BL and LFU did not statistically significantly differ in the subgroups. The mean GA growth rate was: fovea-involving 1.42 ±0.68mm²/y; fovea-sparing 2.10±1.13mm²/y (p=0.00172) and multifocal 1.83±1.11mm²/y; unifocal 1.59±0.86mm²/y (p=0.41230) and bilateral 1.67 ±0.90mm²/y; unilateral 0.87 ±0.63mm²/y (p=0.02480). The mean square-root (sqrt) GA growth rate was: fovea-involving 0.23 ±0.12mm/y; ovea-sparing 0.33±0.14mm/y (p=0.00010) and multifocal 0.30±0.14mm/y; unifocal 0.26±0.13mm/y (p=0.20078) and bilateral 0.27±0.13; unilateral 0.15 ±0.06 (p=0.01209).

Conclusions : Bilaterally affected fovea-sparing subjects, showed the fastest long-term growth rate, irrespective of baseline lesion area or configuration. Accordingly, these subjects might hold the highest potential to express a reduction in GA growth rate under future treatments. As their central VA is not completely affected, they further allow evaluation of structure-function correlations while being treated.

This abstract was presented at the 2024 ARVO Annual Meeting, held in Seattle, WA, May 5-9, 2024.