Analysis of factors affecting the progression of visual field defects in patients with myopia and primary open-angle glaucoma

Abstract

Objective: To investigate the factors affecting the progression of visual field defects in patients with myopia and primary open-angle glaucoma (POAG), and to clarify whether the factors vary in patients with different degrees of myopia. Method: An ambispective cohort study was conducted among patients diagnosed with myopia and POAG from the glaucoma outpatient department at the Zhongshan Ophthalmic Center of Sun Yat-sen University between January 2006 and January 2024. Based on the criteria of functional visual field progression, patients were divided into the progression group and non-progression group, and further divided into the low to moderate myopia subgroup and high myopia subgroup according to the degree of myopia. The patient age, gender, type of glaucoma (high tension glaucoma and normal tension glaucoma), spherical equivalent refraction, best corrected visual acuity (BCVA, recorded as the logarithm of the minimum angle of resolution), intraocular pressure (IOP), central corneal thickness, baseline visual field, history of ophthalmic surgery (corneal refractive surgery and glaucoma surgery), and number of anti-glaucoma medications were summarized. The generalized estimation equation was used for comparison between groups, and the Cox proportional hazards model was used to analyze the factors affecting the progression of visual field defects. Results: A total of 182 eyes from 106 patients were included in this study. There were 57 eyes in the progression group and 125 eyes in the non-progression group. Compared with the non-progression group, the progression group had the older age [43 (29, 53) years old], worse BCVA [0.05 (0.00, 0.17)], greater IOP fluctuation [1.8 (1.3, 2.9)mmHg(1 mmHg=0.133 kPa)], more common baseline central defects [52.6%(30/57)], higher visual field pattern standard deviations [8.92 (5.32, 12.00)dB], lower visual field index [77% (67%, 88%)], and more anti-glaucoma medications [35.1% (20/57) patients used three medications] (all P<0.05). The Cox proportional hazards models showed that the baseline moderate visual field defects [hazard ratio (HR)=2.33, 95% confidence interval (CI): 1.25 to 4.36, P=0.008], baseline central defects (HR=2.09, 95%CI: 1.11 to 3.93, P=0.022), older age (Model A, HR=1.03, 95%CI: 1.00 to 1.05, P=0.017; Model B, HR=1.02, 95%CI: 1.00 to 1.05, P=0.019), and greater IOP fluctuation (Model A, HR=1.54, 95%CI: 1.32 to 1.81, P<0.001; Model B, HR=1.49, 95%CI: 1.26 to 1.75, P<0.001) were risk factors for visual field progression. In the low to moderate myopia subgroup, the increased risk of progression was associated with baseline central defects (HR=5.74, 95%CI: 1.72 to 19.20, P=0.005), worse BCVA (Model A, HR=15.80, 95%CI: 2.07 to 121.00, P=0.008; Model B, HR=12.50, 95%CI: 2.65 to 58.70, P=0.001), and older age (Model A, HR=1.05, 95%CI: 1.02 to 1.08, P=0.002; Model B, HR=1.07, 95%CI: 1.03 to 1.11, P<0.001). In the high myopia subgroup, the increased risk of progression was associated with baseline moderate visual field defects (HR=2.35, 95%CI: 1.12 to 4.92, P=0.024) and greater IOP fluctuation (Model A, HR=1.50, 95%CI: 1.24 to 1.82, P<0.001; Model B, HR=1.52, 95%CI: 1.26 to 1.83, P<0.001). Conclusions: Age, IOP fluctuation, baseline moderate visual field defects, and baseline central defects were the factors affecting the progression of visual field defects in patients with myopia and POAG. There were differences in the influencing factors of visual field progression in patients with different degrees of myopia.