Effect of spironolactone on blood pressure and the renin-angiotensin-aldosterone system in oligo-anuric hemodialysis patients

Background: Through its actions on nonepithelial tissues, including brain, blood vessels, and heart, aldosterone may mediate hypertension, cardiac hypertrophy, and fibrosis. Whether aldosterone has a direct pathogenic role in the development of cardiovascular complications in patients with end-stage renal disease is unknown. Oligo-anuric dialysis patients provide a clinical setting to study the effects of the mineralocorticoid receptor blocker spironolactone that are independent of the diuretic properties of the drug. We performed a randomized, double-blinded, placebo-controlled, crossover study to assess the effect of spironolactone on blood pressure and the renin-angiotensin-aldosterone system in oligo-anuric hemodialysis patients. Methods: Eight hemodialysis patients were administered either spironolactone, 50 mg, or placebo orally twice daily for 2 weeks, followed by a 3-week washout period, after which patients crossed over in their treatment arms for 2 more weeks. Results: Administration of spironolactone for 2 weeks decreased predialysis systolic blood pressure from 142.0 +/- 19.6 to 131.4 +/- 18.2 mm Hg (P < 0.05). Compared with placebo, a 2-week course of spironolactone had no effect on predialysis and postdialysis plasma potassium or aldosterone concentrations or renin activity. Conclusion: When administered for 2 weeks, spironolactone, 50 mg twice daily, reduced predialysis systolic blood pressure, but did not produce hyperkalemia in oligo-anuric hemodialysis patients. (c) 2005 by the National Kidney Foundation, Inc.