Atrial Natriuretic Factor in Patients on Continuous Ambulatory Peritoneal Dialysis

The aim of this study was to compare the levels of the atrial natriuretic factor (ANF) and the renin system in patients on continuous ambulatory peritoneal dialysis (CAPD) with patients on chronic hemodialysis (HD). We studied three groups. The CAPD group comprised 10 patients (25–66 years); the HD group: 10 patients (35–69 years), before (pre-HD) and after (post-HD) a HD session. The control group comprised 10 subjects with normal renal function (29–65 years), matched for age, height, weight, and diastolic pressure with the CAPD group. Blood pressure (BP) and blood samples for plasma renin activity (PRA), plasma aldosterone (PA), and ANF were taken. The BP and levels of ANF, PRA and PA were: in the control group, 121:1:15/75±4 mmHg, 7.3:1:5.6 pmol/L, 1.1±0.8 ng/mL/hour, 0.4:1:0.3 nmol/L. In the CAPD group, 132:1:26/76:1: 12 mmHg (NS), 8.3:1:3.5 pmol/L (NS), 5.6:1:4.4 ng/mL/hour (p<0.001), 4.9±4.0 nmol/L (p<0.001). In the pre-HD, 159±25/95:1: 12 mmHg (p<0.001), 16.0:1:8.5 pmol/L (p<0.005), 11.99±9.0 ng/mL/hour (p<0.001), 2.6:1:2.3 nmol/L (p<0.001). In the post-HD, 145±29/84:1: 15 mmHg (p<0.05 vs CG), 13.4:1:6.9 pmol/L (p<0.05 vs control), 14.9:1:10.3 ng/mL/hour (p<0.001 vs control), 3.8:1:2.9 nmol/L (p<0.001 vs control). There was a positive correlation between BP and ANF in HD patients before ultrafiltration (r=0.700, r=0.772; p<0.05, p<0.01). These data suggest not only a difference in plasma volume, but an indirect role of BP in HD patients. However, in the CAPD group, the normal values of BP and ANF indicate a better volume balance achieved in these particular patients.