Abstract
Purpose :
Recently, systemic oxidative stress has been shown to be an important factor in the pathogenesis of glaucoma. Low systemic antioxidative capacity, which normally counteracts oxidative stress, may be particularly important. Corneal hysteresis (CH), i.e., the viscoelasticity of the cornea, is also associated with glaucoma progression and severity. The purpose of this study was to evaluate the relationship between systemic oxidative stress and CH.
Methods :
The study included 103 patients with open-angle glaucoma (OAG) (male/female = 45/58, mean age 58.5 ± 11.3 years, normal-tension glaucoma/primary OAG = 82/21), examined at the glaucoma clinic of the Tohoku University Hospital Department of Ophthalmology. We used a free radical analyzer (Wismerll Co., Ltd.) to measure biological antioxidant potential (BAP), and an ocular response analyzer (Reichert Ophthalmic Instruments, Inc.) to measure CH, corneal resistance factor (CRF), corneal compensated IOP, and Goldman-correlated IOP. Patients with waveform score measurements of 6.5 or above were included; the average of 3 measurements was used in the analysis.We evaluated the relationship between systemic oxidative stress and other clinical parameters with Spearman’s rank correlationtest and a multi-regression analysis.
Results :
We observed a positive correlation between BAP and CH (r = 0.28, p = 0.03),but not between BAP and CRF, in the female OAG patients. There were no correlations between BAP and either CH or CRF in the male OAG patients. We assigned female patients to two groups based on mean age. We found that BAP waspositively correlated to CH and CRF in the female OAG patients older than 57 years (r = 0.51, p = 0.003; r = 0.49, p = 0.004),but not correlated in the female OAG patients younger than 57 years. Multiple regression analysis revealed that BAP, age and central corneal thickness (CCT) were independent contributing factors to CH (p = 0.02, p = 0.047, p <0.001), and that BAP and CCT were independent contributing factors to CRF (p=0.018, p <0.001), in the older group of female OAG patients.
Conclusions :
Systemic oxidative stress may significantly affect the viscoelasticity of the cornea in female OAG patients older than 57 years.Thus, low systemic anti-oxidative levels and low corneal hysteresis may contribute to glaucoma pathogenesis.Anti-oxidativetreatments might therefore have a neuroprotective effect in older female OAG patients.
This abstract was presented at the 2019 ARVO Annual Meeting, held in Vancouver, Canada, April 28 - May 2, 2019.