Relationship between Oxidative Stress Biomarkers and Visual Field Progression in Patients with Primary Angle Closure Glaucoma

Purpose. To investigate the serum changes of oxidative stress markers and the relationship between these factors and visual field (VF) progression in patients with primary angle closure glaucoma (PACG). Methods. A case-control and a prospective cohort study. A total of 94 patients with PACG and 89 normal controls were enrolled. Furthermore, 94 PACG subjects were followed up for at least two years (once every six months). All participants were evaluated for serum levels of superoxide dismutase (SOD), total antioxidant status (TAS), hydrogen peroxide (H2O2), malondialdehyde (MDA), glutathione peroxidase, glutathione reductase, and detailed eye and systematic examination. Binary logistic regression analysis and Cox regression analysis were performed. Results. The serum levels of SOD and TAS in the PACG group were significantly lower than those in the control group (p < 0.001). Meanwhile, PACG subjects had significantly higher levels of MDA and H2O2 than the normal control subjects (p < 0.001). Serum levels of TAS (OR = 0.773, 95%CI = 0.349 - 0.714, p < 0.001), SOD (OR = 0.975, 95%CI = 0.955 - 0.995, p < 0.001), MDA (OR = 1.155, 95% CI = 1.080 - 1.235, p < 0.001), and H2O2 (OR = 1.216, 95%CI = 1.142 - 1.295, p < 0.001) were independent risk/protective factors for PACG. TAS levels (HR = 0.041, 95%CI = 0.008 - 0.218, p < 0.001), SOD levels (HR = 0.983, 95%CI = 0.971 - 0.994, p = 0.003), and MDA levels (HR = 1.010, 95%CI = 1.001 - 1.018, p = 0.015) at baseline were associated with visual field progression. Kaplan-Meier curves reveal that patients with TAS < 0.95/SOD < 143/ MDA > 12 had a significantly higher percentage of PACG progression (p < 0.05). Conclusions. Decreased levels of TAS and SOD as well as increased levels of MDA at baseline were associated with VF progression in patients with PACG. These findings suggest that oxidative stress was involved in the onset and development of PACG.