Progression Of Age-Related Geographic Atrophy: Role Of The Fellow-Eye

Abstract

 

Purpose:

 

To investigate if the stage of age-related macular degeneration (AMD) of the fellow eye is associated with atrophy progression over time in patients with geographic atrophy (GA) secondary to AMD.

 

Methods:

 

A total of 300 GA eyes of 193 patients, recruited from the prospective FAM (Fundus Autofluorescence in age-related macular degeneration)-Study, were classified in 3 groups according to the AMD stage of the fellow-eye at baseline: (1) bilateral GA, (2) early AMD and (3) exudative AMD. GA areas of study eyes were quantified on fundus autofluorescence images using semi-automated image analysis and progression rates calculated using a 2-level linear mixed-effects model.

 

Results:

 

At baseline, 148 patients belonged to group 1, 16 to group 2 and 29 to group 3, respectively. Univariate analysis showed an average population-specific progression rate of 1.64 mm²/year (95% CI [1.478;1.803]) for group 1, 0.74 mm²/year [0.146;1.342] for group 2 and 1.36 mm²/year [0.937;1.787] for group 3. Although there was a statistical significant influence of the size of baseline atrophy on GA progression rate (conditional F-test: p=0.001), adjustment for this parameter still revealed a statistical significant relationship between the disease status of the fellow eye and atrophy enlargement over time (conditional F-test: p=0.033).

 

Conclusions:

 

The AMD disease stage of the fellow eye determined at baseline examination is associated with atrophy enlargement and thus the extension of corresponding absolute scotoma over time. This may indicate manifestation-dependent disease activity. The identification of prognostic determinants on atrophy progression may not only help to add to our understanding of underlying pathophysiological mechanisms, but also for the design of future interventional trials in GA patients.

 

Clinical Trial:

 

http://www.clinicaltrials.gov NCT00393692

 

Keywords: age-related macular degeneration • clinical (human) or epidemiologic studies: natural history • imaging/image analysis: clinical