title: Racial differences in patients' potassium concentrations during spironolactone therapy for heart failure.
abstract: OBJECTIVE
  To determine whether the effects of spironolactone on potassium homeostasis vary by race by comparing serum potassium concentrations and potassium supplement use in African-American and Caucasian patients receiving spironolactone for heart failure.
  
  
  METHODS
  Retrospective medical record review.
  
  
  METHODS
  Two heart failure centers.
  
  
  METHODS
  Fifty African-American and 67 Caucasian patients with heart failure who were receiving a stable dosage of spironolactone in addition to standard heart failure therapy with an angiotensin-converting enzyme (ACE) inhibitor or angiotensin receptor blocker.
  
  
  RESULTS
  Medical records of eligible patients were reviewed by pharmacists and physicians who specialize in heart failure management. No significant differences were observed in diuretic therapy or renal function between racial groups; however, African-Americans were receiving higher doses of ACE inhibitors. African-Americans had lower serum potassium concentrations (4.2 +/- 0.4 vs 4.5 +/- 0.5 mEq/L, p<0.01) and a higher prevalence of potassium supplementation (48% vs 15%, p<0.01). In a subset of patients, spironolactone therapy was associated with a 2-fold greater increase in serum potassium concentration and a 3-fold greater reduction in potassium supplement use among Caucasians than African-Americans.
  
  
  CONCLUSIONS
  Our findings suggest that a large percentage of patients with heart failure, particularly African-Americans, still require potassium supplementation despite treatment with spironolactone and standard vasodilator therapy.
authors.affiliation: Department of Pharmacy Practice, College of Pharmacy, University of Illinois at Chicago, 60612-7230, USA. humma@uic.edu
authors.forename: Larisa H
authors.initials: LH
authors.lastname: Cavallari
authors.forename: Lucy A
authors.initials: LA
authors.lastname: Fashingbauer
authors.forename: Amber L
authors.initials: AL
authors.lastname: Beitelshees
authors.forename: Vicki L
authors.initials: VL
authors.lastname: Groo
authors.forename: Mary R
authors.initials: MR
authors.lastname: Southworth
authors.forename: Marlos A G
authors.initials: MA
authors.lastname: Viana
authors.forename: Randall E
authors.initials: RE
authors.lastname: Williams
authors.forename: Stephanie H
authors.initials: SH
authors.lastname: Dunlap
mesh_terms: D000319:Adrenergic beta-Antagonists / Q000494:pharmacology / Q000627:therapeutic use; D001741:Black or African American; D000368:Aged; D000806:Angiotensin-Converting Enzyme Inhibitors / Q000494:pharmacology / Q000627:therapeutic use; D019587:Dietary Supplements; D004232:Diuretics / Q000494:pharmacology / Q000627:therapeutic use*; D005260:Female; D006333:Heart Failure / Q000188:drug therapy* / Q000208:ethnology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D011188:Potassium / Q000008:administration & dosage / Q000097:blood*; D012189:Retrospective Studies; D013148:Spironolactone / Q000494:pharmacology / Q000627:therapeutic use*; D044465:White People
chemical_list: D000319:Adrenergic beta-Antagonists; D000806:Angiotensin-Converting Enzyme Inhibitors; D004232:Diuretics; D013148:Spironolactone; D011188:Potassium