Baseline structural parameters measured with optical coherence tomography predict functional progression in open-angle glaucoma patients after five years

Abstract

Purpose : To examine baseline structural parameters and functional progression in open-angle glaucoma (OAG) patients over a five-year period

Methods : 111 OAG patients (mean age 65 ± 10.9 years; 43 male, 68 female) were assessed for optic nerve head morphology and retinal nerve fiber layer (RNFL) thickness by optical coherence tomography every six months for five years. Visual function was evaluated using Humphrey 24-2 visual fields. Functional progression was defined as two consecutive visits with mean deviation decrease ≥2 compared to baseline and/or Advanced Glaucoma Intervention Study score increase ≥2 compared to baseline. Mixed-model ANCOVA was used to test for statistically significant changes from baseline to five-year follow-up. Time to functional progression was analyzed using Cox proportional hazards survival analysis.

Results : Baseline disc area 2.27 (95% CI: 2.14, 2.40) increased at five years to 2.62 (2.47, 2.77), mean change 0.35 (0.25, 0.44; p<0.001). Baseline cup area 1.18 (1.02, 1.35) increased to 1.51 (1.32, 1.70), mean change 0.33 (0.23, 0.43; p<0.001). Baseline average RNFL thickness 74.9 (70.1, 79.7) decreased to 72.8 (67.6, 78.1), mean change -2.1 (-5.1, 0.9; p=0.174). A higher baseline disc area (p=0.008), higher baseline cup area (p=0.003), and lower baseline RNFL temporal thickness (p=0.003) were associated with shorter time to functional progression.

Conclusions : In our study of OAG patients, a larger disc area, larger cup area, and smaller temporal RNFL thickness measured at baseline were associated with a shorter time to functional vision loss after five years.

This is an abstract that was submitted for the 2016 ARVO Annual Meeting, held in Seattle, Wash., May 1-5, 2016.