Oxidative stress in diabetic retinopathy and diabetic nephropathy

: Oxidative stress plays an important role in the pathogenesis of diabetic complications including diabetic retinopathy (DR) and diabetic nephropathy (DN) as suggested by experimental and clinical studies. The study aimed to measure as well as compare total antioxidant capacity (TAC) and malondialdehyde (MDA) levels in type 2 diabetic patients (T2DM) with diabetic retinopathy and diabetic nephropathy. In this cross-sectional study we measured serum TAC, MDA, fasting plasma glucose (FPG), and HbA1c levels in 3 groups of T2DM patients with 110 cases in each group: 1st group without DR and/or DN, 2nd group with DN, and 3rd group with DR. This study was done in a tertiary care hospital from Dec 2019 to Dec 2022. Data was analyzed using version 20 of SPSS software. In DR patients, TAC levels were significantly lower (P=0.000), and FPG and HbA1c levels were significantly higher (P=0.003 & P=0.001 respectively) than in DM and DN patients. However, MDA did not show any significant difference in all groups. In the proliferative DR group, duration of diabetes, MDA levels, FPG levels, and HbA1c levels were significantly high (P=0.027, P=0.033, P=0.014 & P=0.000 respectively) and TAC levels were significantly low (P=0.033) as compared to non-proliferative DR group. : Weakening of the antioxidant defence system with increased oxidative stress in DM is associated with complications like DR and DN and also with the progression of DR to its vision-threatening proliferative stage.