Oxidative Balance and Inflammation in Hemodialysis Patients: Biomarkers of Cardiovascular Risk?

Abstract

During chronic kidney disease, the progressive deterioration of renal function induces several biological/clinical dysfunctions, including enhancement of synthesis of inflammation/oxidative stress mediators. Impaired renal function is an independent cardiovascular risk factor; indeed, cardiovascular complications dominate the landscape of both chronic kidney disease and end-stage renal disease. The aim of this study is to explore the correlation between the global oxidative balance in hemodialysis patients and both inflammatory markers and cardiovascular events. Using photometric tests, this study explored plasmatic oxidative balance in 97 hemodialysis patients compared to a healthy population. In the hemodialysis patients, we showed that oxidative stress values were significantly lower than in controls while effectiveness in the antioxidant barrier was significantly increased in the hemodialysis group. Furthermore, we highlighted a strong correlation between oxidative index and blood levels of C-reactive protein. When patients were divided into two groups based on previous cardiovascular events, we found that subjects with previous cardiovascular events had higher values of both oxidative stress and antioxidant barrier than patients without cardiovascular events. Our results indicated that in hemodialysis patients, the clinical and prognostic significance of oxidative status is very different from general population. As cardiovascular complications represent a strong negative factor for survival of hemodialysis patients, the research of new cardiovascular risk biomarkers in these patients takes on particular importance in order to translate them into clinical practice/primary care.

Figure 1

Correlation between oxidative index and antioxidant barrier values in HD patients (r = Pearson correlation coefficient).

Figure 2

Correlation between oxidative index and PCR (C-reactive protein) values in HD patients (r = Pearson correlation coefficient).

Figure 3

Values of d-ROM (a) and BAP (b) tests in a healthy population (CTR), all hemodialysis patients (HD), hemodialysis patients without cardiovascular events (CVD-), and hemodialysis patients with previous CVD events (CVD+). Data are expressed as mean±SE (Tukey's multiple comparison test, ^∗p < 0,005; ^∗∗p < 0, 0005).