Impact of Cataract Surgery on Progression of Geographic Atrophy in Age-Related Macular Degeneration

Abstract

Purpose: : To determine whether lens status and cataract surgery affect the enlargement rates of geographic atrophy (GA) in patients with age-related macular degeneration (AMD).

Methods: : Longitudinal data on GA progression from two prospective natural history studies in patients with GA were analyzed. The Geographic Atrophy Study (GAS) conducted at the Wilmer Eye Institute included 208 eyes of 129 patients with a median follow-up of 4.3 years (Inter Quartile Range IQR 2.6-6.5). The multicenter Fundus Autofluorescence in AMD (FAM-)Study included 155 eyes of 129 patients with a median review period of 1.8 years (IQR 1.3 - 3.3. All eyes were divided into three groups according to their lens status: (1) phakic (GAS n=157 eyes, FAM-Study n=104 eyes), (2) pseudophakia (n=42; n=16) and (3) cataract surgery during the study (n=9; n=35). In addition, comparison between eyes in progression rate was performed for 8 GAS patients who were phakic in one eye and pseudophakic in the fellow eye (n=8, n=15).

Results: : In the GAS, there was no significant difference between group 1 and group 2 in enlargement rate (GAS mean progression rate 2.5 mm²/year for group 1, 2.8 mm²/year for group 2, t test p = 0.28) For the group 3 GAS patients, the enlargement rate during the interval in which cataract surgery occurred was less than the pre- and/or post-surgical rates of progression in 6 out of the 7 patients who had adequate data for comparison of intervals. Two GAS patients had adequate follow-up both pre- and post-surgery; they had lower progression rates post-surgery than pre-surgery. There was no significant difference in progression rate between eyes in patients who were phakic in one eye and psudophakic in the fellow eye (mean progression rate phakic eyes 2.3 mm²/year, pseudophakic eyes 1.9 mm²/year, p = 0.26 for paired t test).In the FAM-Study, preliminary analysis showed a median atrophy progression of 1.3 mm²/year (IQR 0.7-2.1) for group 1, 1.7 mm²/year (IQR 1.1-3.0) for group 2, and 1.8 mm²/year (IQR 1.0-2.5) for group 3, respectively. Again, statistical analysis did not show a significant difference in progression data between group 1 and group 2 (p =0.15 for Wilcoxon rank-sum test).

Conclusions: : These results suggest that cataract surgery does not confer risk for more rapid progression of pre-existing GA.

Keywords: age-related macular degeneration • clinical (human) or epidemiologic studies: risk factor assessment