POSTDIALYSIS FATIGUE - LACK OF EFFECT OF A BIOCOMPATIBLE MEMBRANE

Tumor necrosis factor-alpha (TNF-alpha) has been shown to have somnoge nic properties. Plasma levels of this cytokine have been found to incr ease significantly during dialysis with a bioincompatible (cuprophane) membrane in patients with postdialysis fatigue (PDF), We conducted a crossover study with random assignment to ascertain whether a biocompa tible membrane might attenuate the increase of TNF-alpha and severity of PDF. Sixteen patients on maintenance hemodialysis underwent dialysi s with either cuprophane (n = 8) or polymethylmethacrylate (PMMA; n = 8) membranes for 1 week and then switched to the opposite membrane dur ing the second week. Predialysis and postdialysis measurements of plas ma TNF-a levels were performed during the first and last dialysis trea tments of each week, A fatigue score was determined from the sum of du ration of fatigue and sleep within 6 hours of the completion of dialys is, TNF-alpha levels increased by an average of 18.3% during dialysis with cuprophane membranes but only 2.4% with PMMA membranes (P = 0.04) . Despite this, fatigue scores remained unaltered (similar to 4 of 6). Hence, the biocompatible membrane, PMMA, failed to alleviate PDF, Thi s suggests that dialytic stimulation of TNF-alpha plays no substantial role in the pathogenesis of PDF. (C) 1998 by the National Kidney Foun dation, Inc.