title: Aldosterone and mortality in hemodialysis patients: role of volume overload.
abstract: BACKGROUND
  Elevated aldosterone is associated with increased mortality in the general population. In patients on dialysis, however, the association is reversed. This paradox may be explained by volume overload, which is associated with lower aldosterone and higher mortality.
  
  
  METHODS
  We evaluated the relationship between aldosterone and outcomes in a prospective cohort of 328 hemodialysis patients stratified by the presence or absence of volume overload (defined as extracellular water/total body water >48%, as measured with bioimpedance). Baseline plasma aldosterone was measured before dialysis and categorized as low (<140 pg/mL), middle (140 to 280 pg/mL) and high (>280 pg/mL).
  
  
  RESULTS
  Overall, 36% (n = 119) of the hemodialysis patients had evidence of volume overload. Baseline aldosterone was significantly lower in the presence of volume overload than in its absence. During a median follow-up of 54 months, 83 deaths and 70 cardiovascular events occurred. Cox multivariate analysis showed that by using the low aldosterone as the reference, high aldosterone was inversely associated with decreased hazard ratios for mortality (0.49; 95% confidence interval, 0.25-0.76) and first cardiovascular event (0.70; 95% confidence interval, 0.33-0.78) in the presence of volume overload. In contrast, high aldosterone was associated with an increased risk for mortality (1.97; 95% confidence interval, 1.69-3.75) and first cardiovascular event (2.01; 95% confidence interval, 1.28-4.15) in the absence of volume overload.
  
  
  CONCLUSIONS
  The inverse association of aldosterone with adverse outcomes in hemodialysis patients is due to the confounding effect of volume overload. These findings support treatment of hyperaldosteronemia in hemodialysis patients who have achieved strict volume control.
authors.affiliation: Division of Nephrology, Buddhist Tzu Chi General Hospital, Taipei Branch, Taipei, Taiwan.
authors.forename: Szu-Chun
authors.initials: SC
authors.lastname: Hung
authors.forename: Yao-Ping
authors.initials: YP
authors.lastname: Lin
authors.forename: Hsin-Lei
authors.initials: HL
authors.lastname: Huang
authors.forename: Hsiao-Fung
authors.initials: HF
authors.lastname: Pu
authors.forename: Der-Cherng
authors.initials: DC
authors.lastname: Tarng
mesh_terms: D000368:Aged; D000450:Aldosterone / Q000097:blood*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D006435:Renal Dialysis / Q000009:adverse effects*; D014883:Water-Electrolyte Imbalance
chemical_list: D000450:Aldosterone