The effect of membrane permeability on ESRD: design of a prospective randomised multicentre trial

The different permeability of high-flux and low-flux dialysis membranes results in different removal capacity, particularly for uremic toxins of middle and large molecular weight. High-flux dialysers have been evaluated in clinical and epidemiological studies for their effect on mortality, morbidity, dialysis-related amyloidosis, nutritional status, response to erythropoietin treatment, dialysis tolerance and the preservation of residual renal function. Many of these studies, however, lack a prospective design and randomised treatment allocation, or have too few patients and too short a follow-up. Therefore, this clinical trial was designed to prospectively investigate the long-term effect of membrane permeability on clinical outcome in a larger number of patients. The primary objective is to compare the effect of membrane permeability on mortality of patients on bicarbonate hemodialysis and treated with a minimum dialysis dose. Patients included in the study should have been on hemodialysis for no longer than one month and have serum albumin 4 g/dl or lower. Patients will be randomised to either the experimental or the control group. During the four-week run-in period the treatment parameters will be established in order to achieve the required dialysis dose. During the maintenance period of three to five years regular visits are scheduled to record clinical and laboratory parameters, to measure Kt/V and to adapt the treatment parameters. Altogether a minimum of 660 patients should be enrolled within a two-year recruitment period.