Online-haemodiafiltration vs. conventional haemodialysis: a cross-over study

The main short-term advantages of haemodiafiltration (HDF) are supposedly better removal of Beta2-microglobulin (ß2-m) and phosphate, and better haemodynamic stability. The main disadvantage is higher costs. The aim of the study was to compare the clinical and biological parameters associated with HDF and high-flux haemodialysis (HD), using a cross-over design, while maintaining the same dialysis parameters. All patients on a 3 × 4 hours schedule were observed during 3 identical 6-months periods: HDF1 - HD - HDF2. The mean values for the 2 last months of each period were compared. A total of 51 patients (76 % males, 45 % diabetic) with a mean age of 74 ± 15 years, and who had been on dialysis for 49 ± 60 months were included. The mean blood flow (329 ± 27 ml/min), dialysate flow (500 ml/min), and convection volumes (21.6 ± 3.2 L) were recorded. Patient medications were not changed. Predialysis blood pressure, phosphataemia, calcaemia, iPTH, Kt/V, nPNA and intradialytic events were similar throughout the 3 periods. Only serum albumin (34. 4 ± 3.6, 35.9 ± 3.4, 34.1 ± 4 g/L, p