A study of oxidative stress, inflammation, and endothelial dysfunction in diabetic and nondiabetic chronic kidney disease pre-dialysis patients

Background: Oxidative stress, inflammation, and endothelial dysfunction represent a key triad for the development and progression of atherosclerosis. Due to chronic low-grade inflammation in chronic kidney disease (CKD), concentrations of various inflammatory, endothelial, and oxidative stress markers are elevated, increasing the risk of atherosclerosis. The present study was undertaken to compare oxidative stress, inflammation, and endothelial dysfunction in diabetic and nondiabetic CKD pre-dialysis patients. Materials and Methods: This was an observational study on 120 CKD pre-dialysis patients: 60 with diabetes and 60 without diabetes. Markers of oxidative stress were measured in blood - malondialdehyde (MDA), ferric reducing ability of plasma (FRAP), paroxonase-1 (PON-1), ischemia-modified albumin (IMA); inflammation - interleukin-6 (IL-6), high-sensitivity C-reactive protein (hsCRP); and endothelial dysfunction - nitric oxide (NO), carotid wall intima-media thickness (CIMT). Comparisons between the two groups for continuous variables were made with the Student's unpaired t-test or Mann-Whitney test and for categorical values with chi(2)-test, as appropriate. Results: MDA, IMA, IL-6, hsCRP, NO, and CIMT were significantly higher, while FRAP and PON-1 were significantly lower in the diabetic group when compared to nondiabetic group (P < 0.001). The number of atherosclerotic plaques was also significantly higher in the diabetic group compared to nondiabetic group. Conclusion: Our study showed increased oxidative stress, inflammation, endothelial dysfunction, and atherosclerosis in diabetic CKD pre-dialysis patients when compared to nondiabetic CKD pre-dialysis patients and in late stages when compared to early stages of CKD in both groups, indicating increased cardiovascular risk in late stages and diabetic CKD pre-dialysis patients.