Insulin and Mineralocorticoids Influence on Extrarenal Potassium Metabolism in Chronic Hemodialysis Patients

Abstract

Insulin-mineral corticoids effects on extrarenal K+ metabolism in dialysis patients. During the inter-dialytic interval in dialyzed patients, hydrogen and potassium ions are regulated by extrarenal mechanisms. We studied the hormonal and acidotic effects on the extrarenal potassium metabolism, in selected, anuric and stable, hemodialysis patients. Fifteen patients, were grouped according to the mean mid-week pre-dialysis K+ over the past 12 months: > 6.0 mEq/L (G1, n=5), = 5.1-6.0 mEq/L (G2, n=5), < or = 5.0 mEq/L (G3, n=5). After a mid-week hemodialysis session and 12 h fasting, they received 1 g/Kg glucose p.os (A). Insulin, aldosterone, renin, pH, HCO3-, glucose, body weight, blood pressure and heart rate were measured before and 60' after the meal. We recorded the same parameters, except insulin, in 15 patients, similarly grouped, before hemodialysis (T0) and on 3 consecutive off dialysis days (T1-T3); G1 received fluorohydrocortisone (FHC) 0.1 mg-0.3 mg/day, according to body weight and G3 spironolactone (SLT) 200 mg per day. G2 were controls (B). (A) A significant rise in glycemia (81 +/- 23 to 157 +/- 52 mg/dL, P<0.001) and insulin (11.8 +/- 6.2 to 46.8 +/- 19.5 microU/mL, P<0.001), with a drop in K+ (5.1 +/- 0.6 to 4.8 +/- 0.7 mEq/L, P=0.001) and aldosterone (453 +/- 373 to 383 +/- 364 pg/mL, P<0.01), were noted at T60 vs. T0, in all groups. Insulin levels correlated negatively (r=-0.54, P<0.04) to serum K+ at T60, in all patients. (B) No major pH, HCO3 and aldosterone changes were observed in the 3 groups. Despite that, K+ dropped in G1 by FHC (6.7 +/- 0.9 to 5.9 +/- 0.6 mEq/L, P<0.05), rose in G3 by SLT (4.4 +/- 0.4 to 5.4 +/- 0.3 mEq/L, P<0.05) and remained unchanged in controls (5.8 +/- 0.2 to 5.8 +/- 0.6 mEq/L), (T0 vs T3 pre-dialysis values). Glucose significantly lowered K+ by promoting adequate insulin secretion. Drugs affecting aldosterone action significantly influenced potassium metabolism. Acid-base balance was not important in K+ handling in steady state anuric dialysis patients.

Effect of mineralocorticoids on interdialytic weight gain in hemodialysis patients with perdialytic hypotension

“…Mineralocorticoids (MC) induce a rise in arterial blood pressure. They have been proposed in the treatment of orthostatic hypotension and in hemodialysis patients, in the treatment of hyperkaliemia 3–6 and of per‐dialytic hypotension 7 . Some research was made about the safety of their use 7 .…”

Aldosterone-receptor antagonism and end-stage renal disease

“…However, increased extrarenal conservation of potassium in anuric ESRD patients has been seen with spironolactone doses of approximately 200 mg/d [32], and, likewise, with other studies in this population having employed daily spironolactone doses in the 300-to 400-mg range [31,33••].…”

Effect of spironolactone on K+ homeostasis and ENaC expression in lymphocytes from chronic hemodialysis patients

“…Studies of Sugarman and Brown [23] in anephric humans receiving an oral potassium load after deoxycorticosterone or spironolactone treatment suggest that mineralocorticoid enhanced the removal of potassium from the extracellular space. However, relatively high doses of spironolactone were used in that study, as well as in the report of Vlassopoulus et al [24]. Recent trials have demonstrated the safety of low-dose spironolactone administration in chronic HD patients [25,26].…”