Long-term Intraocular Pressure Fluctuation Is a Risk Factor for Visual Field Progression in Advanced Glaucoma.

Abstract

Intraocular pressure (IOP) fluctuations increase the risk of visual field progression of primary open-angle glaucoma (POAG) in the advanced stage even when IOP is maintained low on average. The purpose of this study was to identify risk factors associated with the progression of visual field defect in patients with advanced POAG. A retrospective review of medical records was conducted to identify patients who met the Hodapp-Parrish-Anderson criteria for advanced POAG. A total of 122 eyes of 122 patients had undergone IOP measurement with Goldmann applanation tonometer, standard automated perimetry, Cirrus optical coherence tomography, and fundus photography at 6-month intervals. Visual field progression was defined as the deterioration of a minimum of 3 visual field locations more than baseline at 5% levels in 4 consecutive visual fields with 24-2 SITA testing. Thirty-six eyes of 122 eyes (29.5%, 51.9±13.9 y old) showed visual field progression during 100.7±44.2 months of follow-up. The progression group showed greater long-term IOP fluctuations (2.6±1.4 mm Hg) than the no progression group (53.5±13.5 y; 2.0±1.0 mm Hg, P=0.008). Disc hemorrhage was detected more frequently in the progression group (40.5% vs. 17.4%, P=0.005). Multivariate Cox regression analysis revealed long-term IOP fluctuations [hazard ratio (HR)=2.567, 95% confidence interval (CI): 1.327-5.370, P=0.012] and disc hemorrhage (HR=2.351, 95% CI: 1.120-4.931, P=0.024) to be independent risk factors of visual field progression. Patients who showed both disc hemorrhage and long-term IOP fluctuations were at greater risks of progression (HR=2.675, 95% CI: 1.072-6.457, P=0.035). Long-term IOP fluctuations and disc hemorrhage are independent and additive risk factors of visual field progression in advanced glaucoma even at low IOPs. Patients in whom these risk factors are identified require close monitoring and vigorous treatment.