Visual Acuity Loss Associated With Advanced AMD Fundus Lesions and With the Simplified AREDS AMD Severity Scale

Abstract

Purpose:: To assess the 10-year risk of visual acuity loss in subgroups defined using the simplified Age-Related Eye Disease Study (AREDS) AMD Severity Scale and in subjects developing fundus lesions associated with the development of advanced AMD.

Methods:: AREDS participants were followed annually for up to 12 years. Important outcomes were the development of advanced AMD and change in best-corrected visual acuity. Fundus lesions associated with advanced AMD were defined as the presence of one or more of 4 fundus lesions associated with neovascular AMD (including serous detachment of sensory retina, non-drusenoid retinal pigment epithelial (RPE) detachment, subretinal or sub-RPE hemorrhage, subretinal fibrosis), or the presence of geographic atrophy involving the center of the macula. The 10-year risk of vision loss was assessed for eyes developing each of these fundus lesions. AREDS participants were also classified as to risk of progression to advanced AMD using the simplified AREDS AMD Severity Scale. The 10-year risks for progression to advanced AMD and vision loss were assessed for each scale step.

Results:: Loss of visual acuity was associated with each of the AREDS lesions that define advanced AMD and with increasing risk level on the simplified AREDS AMD Severity Scale. Study eyes in AREDS had visual acuity of 20/30 or better at baseline and eyes that did not develop the fundus lesions associated with advanced AMD maintained this level of visual acuity, on average, throughout the study. Development of any of the AREDS lesions that defined neovascular AMD led to mean or median vision acuity of 20/200 or worse within five years of the development of each of the lesions. Development of central GA led to mean or median visual acuity of 20/160 five years after the development of central GA.

Conclusions:: Vision loss is associated with increasing level on the AREDS AMD Severity Scale and with the development of any of the fundus lesions associated with advanced AMD. Because the four fundus lesions associated with advanced AMD are associated with large losses in visual acuity, they can be considered as surrogates in prevention studies for the development of advanced AMD, perhaps obviating the need for routine fluorescein angiography.

Clinical Trial:: www.clinicaltrials.gov NCT00000145

Keywords: age-related macular degeneration • visual acuity • neovascularization