Visual Field Progression in Patients with Primary Angle-Closure Glaucoma Using Pointwise Linear Regression Analysis

Purpose: To evaluate visual field (VF) progression and rate of glaucomatous VF loss in patients with primary angle-closure glaucoma (PACG) using pointwise linear regression (PLR) trend analysis.

Design: Clinic-based retrospective study.

Participants: Primary angle-closure glaucoma patients with 5 or more reliable VF tests and with 5 years or more of follow-up.

Methods: Visual field progression was assessed by PROGRESSOR software version 3.7 (Medisoft, Leeds, United Kingdom) and was defined by the presence of at least 2 adjacent testing points located within the same hemifield that showed progression with a change of -1 dB/year or more (P < 0.01) for inner points or -2 dB/year or more (P < 0.01) for edge points. We also performed a logistic regression analysis to determine the variables associated with rapid progression (defined as mean slope of progressing points ≥-1.5 dB/year).

Main outcome measures: Visual field progression and rate of VF loss.

Results: Of the 1296 patients who were assessed, 398 (30.7%) fulfilled the inclusion criteria of 5 or more VFs and 5 years or more of follow-up. Visual field progression was observed in 63 of 398 eyes (15.8%) according to the PLR criteria. The overall mean rate of VF change for these patients was -0.12±0.51 dB/year over a mean follow-up period of 10.4±3.7 years. There were no significant differences in the age, gender distribution, follow-up duration, or number of VFs between those who showed progression and those who did not (all P > 0.05). The most common sector of VF progression was the superior arcuate area (65%). Rapid progression was found in 36 patients (57%). Multiple logistic regression analysis revealed older age and higher vertical cup-to-disc ratio (VCDR) at presentation as predictors of rapid progression (all P < 0.005) in the progressing group (n = 63).

Conclusions: In patients with PACG being managed in a hospital setting, VF progression was noted in 15.8%, and the overall rate of VF loss was -0.12±0.51 dB/year. The superior arcuate was the most common sector of progression. Older age and higher VCDR at presentation were associated with rapid progression.