Control of plasma aldosterone during chronic hemodialysis.

To investigate the effect of chronic hemodialysis (CH) on adrenal aldosterone release plasma aldosterone (PA), plasma renin activity (PRA), plasma cortisol (PC) and the serum concentrations of potassium (K) and sodium (Na) were measured before and at monthly intervals up to 26 months after initiation of CH in 42 patients with terminal renal failure. Body weight (BW), systolic (BPs) and diastolic (BPd) blood pressure were determined simultaneously. With 2 exceptions PA, PRA and PC as well as BW, BPs and BPd showed no significant changes. Following month 2 K was always significantly higher than the starting value while significantly higher Na values were observed in 12 of 26 different test periods (P less than 0.05--less than 0.001). Correlation analysis between the various parameters determined in this study revealed in 16 of 26 different months a significant relationship between PA and PRA (P less than 0.05--less than 0.001) and as expected in 20 of 26 between BPs and BPd (P less than 0.05--less than 0.001). Only at times were punctual correlations seen between any of the remaining parameters. Our results demonstrate that the prime influence of the renin angiotensin system on PA remains unaltered during CH. We conclude that the observed punctual correlations between the various parameters determined in this study are random and do not reflect a true relationship.