Abstract
Purpose :
To assess the relationship between changes in structural parameters of the optic nerve head (ONH) and functional progression in open-angle glaucoma (OAG) patients with and without diabetes mellitus (DM)
Methods :
111 OAG patients (20 with DM, 91 without DM) were assessed for ONH morphology assessed by Heidelberg retinal tomography 3 every six months for five years. Visual function was monitored with Humphrey 24-2 visual fields. Functional progression was defined as two consecutive visits with a mean deviation decrease ≥2 compared to baseline and/or Advanced Glaucoma Index Study score increase ≥2 compared to baseline. Mixed-model ANCOVA was used to test for statistically significant change from baseline to five-year follow-up. Time to functional progression was analyzed using Cox proportional hazards survival analysis. Interactions were tested to determine if the effects of the factors on progression time differed by diabetes status.
Results :
All results are reported from baseline to five years. In OAG patients with DM, cup area increased from 0.860 to 0.904, change of 0.043 (95% CI: -0.034, 0.117). Cup volume increased from 0.286 to 0.306, change of 0.020 (-0.023, 0.062). Cup/disc ratio increased from 0.404 to 0.420, change of 0.017 (-0.021, 0.054). Mean cup depth increased from 0.290 to 0.309, change of 0.018 (-0.008, 0.045). In patients without DM, cup area increased from 0.888 to 0.925, change of 0.036 (-0.009, 0.080). Cup volume increased from 0.297 to 0.321, change of 0.023 (0.002, 0.045). Cup/disc ratio increased from 0.419 to 0.439, change of 0.020 (-0.002, 0.042). Mean cup depth increased from 0.302 to 0.310, change of 0.008 (-0.001, 0.017). In OAG patients with DM, higher cup area (p=0.021), cup volume (p=0.011), cup/disc ratio (p=0.042), and mean cup depth (p=0.001) were more predictive of a shorter time to functional progression, compared to patients without DM.
Conclusions :
In this group of patients with OAG, structural ONH parameters predict a shorter time to functional glaucoma progression in diabetics, compared to non-diabetics. This data suggests that OAG patients with and without diabetes may experience glaucoma progression differently.
This is an abstract that was submitted for the 2016 ARVO Annual Meeting, held in Seattle, Wash., May 1-5, 2016.