Risk factors associated with beta-peripapillary atrophy in individuals of African ancestry with primary open-angle...

Beta-Peripapillary Atrophy (beta-PPA) is an optic nerve head change associated with primary open-angle glaucoma (POAG). We evaluated demographic, ocular, and genetic risk factors for beta-PPA in individuals of African ancestry with POAG.

POAG cases were recruited from the Primary Open-Angle African American Glaucoma Genetics (POAAGG) study. Beta-PPA was defined as hypopigmentation with visible choroidal vessels and sclera adjacent to the optic disc. Univariable and multivariable regression models assessed risk factors for the presence and extent of beta-PPA.

Among 3381 eyes, 969 (28.6%) had beta-PPA. Beta-PPA was associated with older age (OR = 2.90, p < 0.001) and larger vertical cup-to-disc ratio (CDR) (OR = 1.58, p = 0.007), and was less common in females (OR = 0.53, p < 0.001). Beta-PPA presence was negatively associated with grey crescent (OR = 0.47, p = 0.01), neural rim notching (OR = 0.43, p = 0.01), and cylindrical (OR = 0.55, p < 0.001) or bean pot cup shapes (OR = 0.59, p < 0.001). Larger beta-PPA area was linked to older age (p = 0.008) and large vertical CDR (p = 0.03), but was less likely with conus pigmentosus (p = 0.001), deeper cup depth (p = 0.006), higher IOP (p = 0.005), and rounder discs (p = 0.01). Higher polygenic risk score (p = 0.007) and presence of the SNP rs34957764 in ROCK1P1 (p = 0.053) were associated with beta-PPA, but the same SNP was also associated with lesser area of beta-PPA (p = 0.03). Regions of beta-PPA correlated with greater RNFL loss (p < 0.01).

Beta-PPA is strongly associated with older age and high CDR among individuals with POAG. These regions are vulnerable to RNFL loss.