Long-term progression and risk factors in primary open-angle glaucoma in clinical care

The aim of the present study was to investigate the perimetric progression rate and associated risk factors in open-angle glaucoma in clinical practice.

This was a retrospective study based on clinical chart reviews of patients with primary open-angle glaucoma (POAG) followed up for more than 5 years with ≥5 SITA standard visual fields. Demographics, visual acuity (VA), central corneal thickness (CCT), intraocular pressure values (IOP), treatment (number of medications), visual fields (VFs), and associated systemic pathologies were recorded. Patients were followed up every 3–6 months and identical tests were performed. The VF progression rate was calculated as slope of mean deviation (MD) over time using the Glaucoma Progression Analysis software.

In all, 69 eyes from 69 patients with POAG were included in the study and followed up for a mean period of 72.9 months (SD ± 31.7). The mean MD at the start was −4.4 dB (SD ± 6.0), with a mean number of VF tests of 8.3 (SD ± 2.9). The progression rate reached −0.18 ± 0.1 db/year. The mean IOP at all visits decreased over time from 18.2 mm Hg to 16.5 mm Hg (p < 0.05). A step-wise one-way ANOVA regression analysis concluded that for the MD slope the significant predictors were final MD level (R ² = 0.126, p = 0.003) and a combination between baseline and final MD level (R ² = 0.656, p = 0.000). Systemic factors such as sex, positive history of cardiovascular diseases, and hypertension reached no statistical relevance in terms of increased risk or significant association with glaucoma progression. Diabetes had a borderline significance (p = 0.07) as a “protective factor” against progression, as more “stable” cases were associated with diabetes than “progressing” ones.

The rate of VF changes in POAG correlated with and dependent on the baseline/final MD level; additional risk factors reached no statistical significance in our clinical care glaucoma study.