Abstract
Purpose :
We performed a retrospective study to identify demographic and ocular characteristics associated with six identifiable optic disc phenotypes in Primary Open Angle Glaucoma (POAG) patients.
Methods :
Records of patients from the UCLA Stein Glaucoma Division between 1997 and 2019 were reviewed; included were those with a diagnosis of POAG, one disc photo within two years of a visual field (VF), ≥ 2 VFs with Mean Deviation (MD) > -10dB, Pattern Standard Deviation (PSD) probability <0.05, and a Cirrus Optical Coherence Tomography (OCT) with optic disc area between 1.14 and 3mm2. Poor quality images were excluded. The photos were classified independently by three masked glaucoma specialists into disc phenotypic subgroups, according to standard reference photographs: 1) Concentric rim thinning, 2) Focal rim thinning, 3) Acquired pit of the optic nerve (APON), 4) Tilted (with or without peripapillary atrophy (PPA)), 5) Extensive PPA, and 6) Broad rim thinning. Covariates included age, race/ethnicity, sex, family history of glaucoma, smoking status, hypertension, cardiovascular disease, diabetes, visual acuity (LogMAR), IOP, refractive error, number of medications, central corneal thickness (CCT), visual field MD and PSD, disc area and RNFL thickness. Multinomial Logistic Regression analysis included all covariates.
Results :
In 420 eyes of 420 patients, phenotypes included 127 Concentric thinning (30%), 117 Focal thinning (28%), 95 Broad thinning (23%), 45 Tilted (11%), 22 Extensive PPA (5%) and 14 APON (3%). Variables with statistically significant differences (p < 0.05) between phenotypes included sex, race, age, refraction, mean PSD, disc area, RNFL. Phenotype traits of interest included 1) Females were more likely to have Focal Thinning, APON and Broad Thinning; 2) Asians were more frequently tilted; 3) African descent were more likely to have Concentric thinning; and 4) APON was less likely to have cardiovascular disease and diabetes.
Conclusions :
This study reports six phenotypic classifications of POAG patients, with emergence of different and ocular and systemic differences between phenotypes. Future refinement of phenotypes should allow improved individualization of patient care and enhance genetic associations.
This abstract was presented at the 2022 ARVO Annual Meeting, held in Denver, CO, May 1-4, 2022, and virtually.