Acute Effects of Hemodiafiltration Versus Conventional Hemodialysis on Endothelial Function and Inflammation: A Randomized Crossover Study

Endothelial dysfunction and chronic inflammatory process are prevalent in patients with end-stage renal disease (ESRD) on maintenance hemodialysis (HD). The aim of this study was to evaluate the acute and short-term effects of online hemodiafiltration (OL-HDF) versus conventional HD on endothelial function and inflammation. A prospective, randomized, crossover trial. Twenty stable ESRD patients undergoing chronic HD treatments were randomly assigned with a 1:1 ratio to conventional HD and to OL-HDF both for 2 weeks (either HD followed by OL-HDF or OL-HDF followed by HD). Markers of endothelial dysfunction such as flow-mediated dilatation (FMD) of the brachial artery, soluble endothelial protein C receptor (sEPCR), and soluble thrombomodulin (sTM) were measured at baseline, after the first dialysis session and after 2 weeks. Meanwhile, serum interleukin 6 (IL-6) and high-sensitivity C-reactive protein (hs-CRP) levels were measured as well. Both a single OL-HDF session and 2-week OL-HDF significantly improved brachial FMD% (18.7 ± 6.9% at baseline; 21.5 ± 5.4% after the first dialysis; 21.5 ± 5.7% after 2 weeks; P < 0.05 vs baseline), decreased the levels of sEPCR (from 394.4 [297.9–457.0] ng/ml at baseline to 234.7 [174.1–345.5] ng/ml after the first dialysis, and to 191.5 [138.2–255.0] ng/ml after 2 weeks; P < 0.01 vs baseline) and sTM. In contrast, HD did not change FMD%, even increased the levels of sEPCR and sTM. A reduction in IL-6 level was observed in OL-HDF patients after 2-week dialysis, while IL-6 did not change in HD patients. There was no significant difference in change of hs-CRP level between the OL-HDF and HD treatments. OL-HDF has both acute and short-term beneficial effects on endothelial dysfunction compared to conventional HD.