P1105CAN BETTER EFFICACY OF MIDDLE WEIGHT MOLECULES REMOVAL IN DIALYSIS PATIENTS TREATED WITH MEDIUM CUT-OFF MEMBRANES PREDICT SUPERIORITY OVER CONVENTIONAL HIGH FLUX DIALYSERS?

Abstract

Abstract Background and Aims During last two decades there was a significant improvement in dialysis field, especially with introducement of high flux haemodialysis and on-line haemodiafiltration. In recent years, expanded haemodialysis has emerged as a new attempt to imrove effectiveness of dialysis. These so called medium cut-off membranes (MCO), allow removal of wider range of uremic toxins, especially middle weight molecules, most of which have important role in chronic inflammation and mortality. The aim of this prospective pilot study was to evaluate the effectiveness of middle molecules and other uremic toxins removal in patients treated with medium cut-off membrane (Theranova 500tm, Baxter), compared with patients on conventional high flux dialysis programme. Method We examined 10 patients on chronic haemodialysis programme, five of them dialyzed with Theranova 500tm dialyser for one year, and other five patients dialyzed with high flux membranes (polysulfone membrane, 1.8m2) during the same period. Patients were matched according to their age, sex, main disease, and the beginning of dialysis. Analyzed laboratory parameters were urea, creatinine, calcium, phosphorus, PTH, and hemoglobin, on the beginning of the study and after one year follow up, while hepcidin and β2 microglobulin levels were measured only in the end of follow up period. We used descriptive and analytic statistical methods (T test for independent and dependent means). Results Patients were divided in two groups, Group 1 - dialyzed with Theranova, and Group 2- patients on high flux haemodialysis, both followed during one year period (Group 1: 63.2±7.01 years, 3 males and 2 women, one of them with polycystic kidney disease (PCKD), the other four with hypertension as main disease, median dialysis time 54.6±8.32 months, Group 2: 63±6 years, 3 males, 2 women, main disease in one was PCKD, in other four hypertension, median dialysis time 53.6±17.98months). Our patients didn’t differ statistically in basic examined laboratory parameters on the beginning of examination (mean urea 21.38±2.15 vs. 27.44±3.93 mmol/ (p>0.05), mean creatinine 936±88.5 vs. 927.6±98.8µmol/L, mean albumin 40±2.54 vs 39.8±2.77g/L (p>0.05), mean calcium 2,24±0.16 vs 2.21±0.17mmol/L (p>0.05), mean phosphorus level 1,84±0.39 vs 1.67±0.56mmol/L (p>0.05), mean parathyroid hormone level 266.16±279.64 vs 236.14±43.99pg/mL (p>0.05), and mean hemoglobin 122.2±5.72 vs 106.4±8.62g/L (p>0.05). In patients on high flux haemodialysis programme there was no significant change in examined parameters during one year follow-up (for all examined parameters p value was >0.05). After switching the first group on Theranova dialysers for one year there was small but statistically significant rise in urea (23.26±2.02mmol/L, p<0.05), and also statistically significant decrease in serum creatinine level (840.2±75.34µmol/L, p<0.05) in this group, while other parameters were not statistically significant. Comparing two groups after one year follow up, there was statistically significant higher level of hemoglobin in the first group (112.2±7.46 vs. 102g/L ±4.47, p<0.05), and statistically significant decrease of beta-2 microglobuline (27.41±2.58 vs. 33.82± 2.47ng/mL, p<0.05) and hepcidin (75.64±32.2 vs 100.26±10.58ng/mL, p<0.05), while other parameters didn’t show statistical significance. Conclusion Our results implicate better clearance of middle weight molecules (B2M, hepcidin) in patients treated with Theranova 500 tm membrane, which could suggest anti-inflammatory effect of medium cut-off membranes, additionaly with the higher hemoglobin level after one year treatment, comparing to conventional high flux dialysis. Our results are promising, but need to be confirmed in larger randomized trials.