THE CHANGE OF PLASMA SCLEROSTIN AND OTHER BIOMARKERS IN HEMODIALYTIC PATIENTS USING DIALYZER WITH MEDIUM CUT-OFF MEMBRANE

Abstract Background and Aims Protein-bound toxins and uremic toxins with middle molecular weight usually develop uremic symptoms in patients with advanced chronic kidney disease (CKD) or end-stage renal disease (ESRD). Although the effect on uremic toxicity of the molecules is not proven yet, middle molecules or larger middle molecules is regarded with important substance concerning of development of uremic symptoms and cardiovascular complication, particularly in CKD patients. Hemodialysis (HD) or hemodiafiltration (HDF) using dialyzer with high flux membrane provided improved clearance for uremic toxins with middle molecular weights. However, uremic toxins with larger middle molecular weight could not be easily removed through above methods. Medium cut-off (MCO) membrane can remove larger middle molecules which can be not removed through high flux membrane and HDF. From this perspective, chronic use of MCO membrane lowering the plasma concentration of larger middle molecules associated with cardiovascular complications including vascular calcification may give beneficial effect, particularly in patients with ESRD. Method Twenty-five patients undergoing chronic hemodialysis were prospectively analyzed for 6 months. We randomly divided enrolled patients into two groups: control group and MCO group. Patients in the control group used dialyzer with high flux membrane and patients in MCO group used dialyzer with MCO membrane. The enrolled patients performed hemodialysis thrice a week during 6 months. We measured plasma levels of several biomarkers at baseline and 3-month and 6-month through the multiplexing using Luminex® technology. In this prospective study, we performed comparative analysis with larger middle molecules, such as CXCL16, sclerostin, and FGF-23, in both groups. Results The plasma levels of all biomarkers at baseline did not show significant difference between two groups (CXCL16: p =0.904, Sclerostin: p =0.322, FGF-23: p =0.065, respectively). However, plasma sclerostin levels at 3-month and 6-month were significantly lower in MCO group (p = 0.060, p <0.005, respectively). In addition, even after analysis of covariance through ANCOVA analysis, plasma sclerostin levels at 3-month and 6-month were significantly lower in MCO group compared with the control group (p = 0.042, p =0.001, respectively). But, there was no a significant decrease of plasma sclerostin levels according to time, particularly in MCO group (p = 0.157, p =0.412, respectively) (Figure 1). Conclusion This study showed the 6-month outcome for changes of the plasma levels of larger middle molecules, including CXCL16, sclerostin, and FGF-23, particularly in dialytic patients using dialyzer with MCO membrane. Plasma sclerostin associated with vascular calcification showed decreasing tendency during 6 months after application of MCO membrane, but, there was no statistical significance. However, plasma levels of sclerostin were significantly lower in dialytic patients using MCO membrane than those using high flux membrane at 3 and 6 months, respectively. Therefore, hemodialysis using dialyzer with MCO membrane may be an option to attenuate cardiovascular complications in ESRD patients.