Total antioxidant in patients with diabetic retinopathy examination of status and total oxidant status levels

Purpose: DRP is the most common microvascular complication of diabetes. Many mechanisms have been described in the pathogenesis of retinopathy. Oxidative stress plays an important role in the development of DRP. In this study, we aimed to investigate the role of TAS, TOS and OSI levels, as markers of oxidative stress, in the pathogenesis of diabetic retinopathy and their role in the early diagnosis and treatment of retinopathy. Materials and Methods: Thirty patients with diabetic retinopathy between the ages of 18-75, 34 patients with diabetes but no retinopathy, and 32 healthy control groups without a known chronic disease were included, who applied to the Internal Medicine and Ophthalmology outpatient clinic of Düzce University Faculty of Medicine between May 2021 and December 2021. Demographic data of the patients were recorded during the examination. All patients and healthy controls were screened for retinopathy using Optical Coherence Tomography (OCT) in the Ophthalmology Outpatient Clinic. For hemogram and biochemical parameters, the results of the patients who were recorded in written or electronic records in their routine outpatient clinic controls were used. TAS and TOS measurements were analyzed by colorimetric method after calibration-control procedures on RelAssay Diagnostics brand commercial kits in MINDRAY-BS400 brand device. Results are given in TAS mmol/L, TOS µmol/L. TOS/TAS ratio and OSI value were calculated. All obtained data were evaluated using SPSS 26.0 statistical package program. Results: A total of 96 patients were included in the study. Gender distribution, marital status, BMI, waist and hip circumferences were similar between the groups. DM duration, HbA1C, FPS, Proteinuria and TG levels were found to be higher in the group with DRP. While TOS measurements were found to be the lowest in the control group with a mean of 8.11 ± 2.87 µmol/L in the group with DRP, µmol/L 5.72 ±1.44 in the group without DRP, and 4.69 ± 1.40 µmol/L in the control group, it was statistically significant in the patient group with DRP. found high. TAS was found to be significantly higher with 1.26 ± 0.20 mmol/L in the control group and low in the diabetic patient group. 1.09 ± 0.171 mmol/L in the group with retinopathy, 1.16 ± in the group with DM without retinopathy. It was found to be low as 0.18 mmol/L, but it was not found to be statistically significant. The OSI value was found to be 0.76 ± 0.29 in the group with DRP and was found to be high, consistent with the TOS value. A positive correlation was observed between TOS and OSI levels and FPS, HbA1C, TSH, and TG. In the multivariate logistic regression analysis performed to predict DRP, total insulin dose, use of bolus insulin and diuretics, and high TOS and OSI levels were determined as an independent risk for diabetic retinopathy. Conclusion: In our study, by comparing diabetic cases and healthy control groups; It has been shown that low TAS levels are closely related to diabetes itself, but it is insufficient to show retinopathy. TOS and OSI measurements have high sensitivity and specificity in predicting the development of diabetic retinopathy. Disruption of the balance between oxidant and antioxidant, oxidative stress has been shown to play an important role in the etiopathogenesis of diabetic retinopathy. Calorimetric measurements of TOS and OSI levels may contribute to the early diagnosis, treatment and follow-up of diabetic retinopathy. However, further prospective studies are needed in this area. Key words: diabetic retinopathy, oxidative stress, TAS, TOS, OSİ