Reticular pseudodrusen: a risk factor for geographic atrophy in fellow eyes of individuals with unilateral choroidal neovascularization

Abstract

Purpose: To determine whether reticular pseudodrusen (RPD) confer an increased risk of progression to late-stage age-related macular degeneration (AMD) in fellow eyes of those recently diagnosed with unilateral choroidal neovascularization (CNV).

Design: Retrospective study.

Participants: Two hundred consecutive participants with CNV secondary to AMD in 1 eye and no signs of late-stage AMD in the fellow eye.

Methods: Clinical examination and comprehensive retinal imaging, including spectral-domain optical coherence tomography, near-infrared reflectance (NIR), and color fundus photography, at baseline and every follow-up visit.

Main outcome measures: Incidence of geographic atrophy (GA) and CNV in the fellow eye.

Results: Mean age ± standard deviation was 77±7 years, and 61% of the cohort were female. Fifty-eight percent (n = 116) had RPD, 68% had drusen of 125 μm or more, 36% had pigmentary changes, 10% had both drusen of 125 μm or more and pigmentary changes, and 17% had only RPD in their fellow eyes. After a mean follow-up of 2.3 years, CNV developed in 36% of patients and GA developed in 14% of patients. Those with RPD demonstrated late-stage AMD (61% vs. 33.4%; P <0.001) and GA (22.4% with RPD vs. 2.4% without RPD; P <0.001) more often. The presence of reticular pseudodrusen was an independent risk factor for the development of GA (hazard ratio [HR], 4.93; P = 0.042), but not for CNV (HR, 1.19; P = 0.500), at least within the follow-up of this study. Both drusen of 125 μm or more and pigmentary changes at baseline were significant risk factors for the development of CNV and GA (HR, 1.96-11.73; P ≤0.020).

Conclusions: Reticular pseudodrusen seem to confer an increased risk of progression to GA, in addition to drusen and pigmentary changes. The presence of RPD needs to be taken into account when discussing a patient's prognosis and planning management.

Figure 1

Kaplan-Meier plots for time until progression to choroidal neovascularization (CNV, panel A) and geographic atrophy (GA, panel B). Those with reticular pseudodrusen (black line) had a significantly shorter time to progression to GA compared to those without (grey line; p<0.001). No difference was found for progression to CNV (p=0.355).

Figure 2

Kaplan-Meier plots for time until progression to late-stage age-related macular degeneration (AMD; A), geographic atrophy (GA; B) and choroidal neovascularization (CNV; C), stratified by number of risk factors (RF; none, drusen and/or pigment, reticular pseudodrusen (RPD), and RPD + drusen and/or pigment). For both, CNV and GA, patients with all risk factors (RPD, drusen and/or pigment) progress the fastest (p<0.001 for any late-stage AMD, p<0.001 for GA and p=0.015 for CNV). Please not that no patient with no risk factors develops GA while a number of patients with no risk factors develop CNV in their fellow eye during follow up.