title: Association of hyponatremia to diuretic response and incidence of increased serum creatinine levels in hospitalized patients with acute decompensated heart failure.
abstract: OBJECTIVE
  Although hyponatremia is a prognostic factor in acute heart failure (AHF), its influence on the acute clinical course of heart failure is unknown. Our objective was to evaluate the association of hyponatremia with diuretic response, renal function, and clinical outcomes in AHF.
  
  
  METHODS
  A retrospective study included 499 hospitalized AHF patients treated with intravenous loop diuretics for ≥48 h. Patients were grouped by nadir sodium concentrations (normonatremic, NN) ≥135 mEq/l, (mild hyponatremia, MHN) 130-134 mEq/l, and (moderate to severe hyponatremia, MSHN) <130 mEq/l. Association to diuretic response and clinical outcome was assessed.
  
  
  RESULTS
  The incidence of hyponatremia was 54% (36% MHN, 18% MSHN). Maximum diuretic dose (furosemide equivalents: NN 84 ± 132 mg/day vs. MHN 114 ± 165 mg/day vs. MSHN 249 ± 450 mg/day, p < 0.001) and incidence of diuretic regimen escalation (NN 11% vs. MHN 16% vs. MSHN 44%, p < 0.001) were significantly higher in patients experiencing hyponatremia. Hyponatremia was also associated with a higher incidence of acute increases in serum creatinine (NN 27% vs. MHN 45% vs. MSHN 63%, p < 0.001), greater increases in blood urea nitrogen, longer hospital stay, and higher mortality. Outcome disparities to NN patients were similar whether hyponatremia was acute or present upon admission.
  
  
  CONCLUSIONS
  Acute or admission hyponatremia, especially <130 mEq/l, in AHF patients is associated with greater diuretic requirements, higher incidence of serum creatinine increases, and a poorer outcome. Alternative treatments warrant evaluation in these patients.
authors.affiliation: Department of Clinical Pharmacy and Pharmaceutical Economics and Policy, University of Southern California, Los Angeles, Calif., USA.
authors.forename: Tien M H
authors.initials: TM
authors.lastname: Ng
authors.forename: Diana X
authors.initials: DX
authors.lastname: Cao
authors.forename: Komal A
authors.initials: KA
authors.lastname: Patel
authors.forename: Yee May
authors.initials: YM
authors.lastname: Wong
authors.forename: Megha
authors.initials: M
authors.lastname: Prasad
authors.forename: Mimi
authors.initials: M
authors.lastname: Lou
authors.forename: Uri
authors.initials: U
authors.lastname: Elkayam
mesh_terms: D000208:Acute Disease; D000368:Aged; D003404:Creatinine / Q000097:blood; D004232:Diuretics / Q000008:administration & dosage*; D005260:Female; D006333:Heart Failure / Q000150:complications* / Q000188:drug therapy; D006760:Hospitalization; D006801:Humans; D007010:Hyponatremia / Q000209:etiology*; D015994:Incidence; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D012189:Retrospective Studies; D012964:Sodium / Q000097:blood
chemical_list: D004232:Diuretics; D012964:Sodium; D003404:Creatinine