Comparison between hemofiltration and hemodiafiltration in a long-term prospective cross-over study.

Background: The objective of the study was to compare the convective treatment modes, on-line hemofiltration (HF) and on-line hemodiafiltration (HDF), regarding cardiovascular tolerance and effects on blood pressure, when applied under similar conditions in stable dialysis patients.

Methods: 39 clinically stable dialysis patients were treated with HD for 6 months (run-in period), followed by HF and HDF in random order for 2x6 months. Similar biocompatibility (same membrane and fluid quality), similar treatment time and urea Kt/V were achieved using AK100/200 ULTRA machines, polyamide membranes in low-flux and high-flux versions and appropriate adjustment of blood flow rate (Qb) and dilution ratio (Qb/Qinf).