Taha Abu Tahir, Shen Liangbo Linus, Diaz Antonio, Chahal Noor, Saroya Jasmeet, Sun Mengyuan, Allingham Michael J, Farsiu Sina, Yiu Glenn, Keenan Jeremy D, Stewart Jay M
Department of Ophthalmology, University of California, San Francisco, San Francisco, California.
Institute of Cardiovascular Diseases, Gladstone Institute, San Francisco, California.
Ophthalmol Sci. 2024 Sep 12;5(1):100620. doi: 10.1016/j.xops.2024.100620. eCollection 2025 Jan-Feb.
To investigate the association between rim area focal hyperautofluorescence (RAFH) signals and geographic atrophy (GA) growth rates, as well as the impact of oral metformin on the longitudinal change of RAFH.
Secondary analysis of a randomized controlled trial.
Seventy-one eyes from 44 participants with GA and ≥6 months of follow-up in the METformin for the MINimization of geographic atrophy progression study.
Fundus autofluorescence images were captured using a 488 nm excitation wavelength. Two masked graders identified and measured RAFH lesions using proprietary semiautomatic segmentation software and ImageJ. We calculated RAFH by dividing the areas of hyperautofluorescence within a 450-μm rim circumscribing the GA by the total area enclosed within this rim.
Longitudinal changes in RAFH and GA area.
Baseline RAFH was positively associated with the baseline square root of GA area 0.065/year ( < 0.001). In the entire study cohort, higher baseline RAFH was associated with a faster GA area growth rate in mm/year (Spearman's ρ = 0.53; < 0.001). The association became weaker in square root-transformed GA area growth (ρ = 0.19, = 0.11) and perimeter-adjusted GA growth rate (ρ = 0.28, = 0.02), achieving statistical significance only in the latter. When this analysis was stratified into 3 baseline GA tertiles, the first and second tertiles showed weak to moderate association with statistical significance in all 3 modes of GA growth rates. Rim area focal hyperautofluorescence increased slightly but significantly over time at 0.020/year ( < 0.01). Rim area focal hyperautofluorescence increased slightly but significantly over time at 0.020/year ( < 0.01). The use of oral metformin was not significantly associated with the change in RAFH over time compared with the observation group (0.023/year vs. 0.016/year; = 0.29).
Increased baseline RAFH is associated with faster GA area progression. However, the effect size of this association may depend on the baseline GA lesion size such that small to medium-sized GA lesions display this relationship regardless of the mode of the calculation of GA growth rate.
Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.
研究边缘区域局灶性高自发荧光（RAFH）信号与地图样萎缩（GA）增长率之间的关联，以及口服二甲双胍对RAFH纵向变化的影响。
一项随机对照试验的二次分析。
在二甲双胍最小化地图样萎缩进展研究中，44名患有GA且随访时间≥6个月的参与者的71只眼睛。
使用488nm激发波长采集眼底自发荧光图像。两名经过盲法培训的分级人员使用专有的半自动分割软件和ImageJ识别并测量RAFH病变。我们通过将GA周围450μm边缘内的高自发荧光区域面积除以该边缘内的总面积来计算RAFH。
RAFH和GA面积的纵向变化。
基线RAFH与GA面积的基线平方根呈正相关（0.065/年，P<0.001）。在整个研究队列中，较高的基线RAFH与更快的GA面积年增长率相关（Spearman相关系数ρ=0.53，P<0.001）。在平方根转换后的GA面积增长（ρ=0.19，P=0.11）和周长调整后的GA增长率（ρ=0.28，P=0.02）中，这种关联变弱，仅在后者中具有统计学意义。当该分析分层为3个基线GA三分位数时，第一和第二个三分位数在所有3种GA增长率模式中均显示出弱至中度的关联且具有统计学意义。边缘区域局灶性高自发荧光随时间略有但显著增加，为0.020/年（P<0.01）。与观察组相比，口服二甲双胍与RAFH随时间的变化无显著关联（0.023/年对0.016/年，P=0.29）。
基线RAFH增加与更快的GA面积进展相关。然而，这种关联的效应大小可能取决于基线GA病变大小，以至于无论GA增长率的计算方式如何，中小型GA病变均显示出这种关系。
专有或商业披露信息可在本文末尾的脚注和披露中找到。
