Encephalopathy in patients on continuous ambulatory peritoneal dialysis and patients on chronic haemodialysis.

A group of 121 patients, 22 with a preterminal chronic renal insufficiency (PCRI), 74 on chronic haemodialysis (CHD), and 25 on continuous ambulatory peritoneal dialysis (CAPD), was evaluated by means of neurophysiological and neuropsychological studies to detect signs of central nervous system dysfunction. CHD patients were studied the day before dialysis treatment. In each patient the neurophysiological and neuropsychological studies were performed on the same day. The same overall result emerged from the neurophysiological and neuropsychological studies: all three patient groups showed significant deviations from the values obtained from a healthy reference group, whereas no differences were found between the three patient groups. Biochemical variables (a.o. PTH, Al, PO4) showed inconsistent or only minor correlations with the encephalopathic parameters. Apparently traditional biochemical variables are not a reliable measure to safeguard renal patients from neurotoxic damage. With respect to central nervous system dysfunction CAPD appears to be as 'safe' as CHD.