title: Dialysate Potassium, Serum Potassium, Mortality, and Arrhythmia Events in Hemodialysis: Results From the Dialysis Outcomes and Practice Patterns Study (DOPPS).
abstract: BACKGROUND
  Sudden death is a leading cause of death in patients on maintenance hemodialysis therapy. During hemodialysis sessions, the gradient between serum and dialysate levels results in rapid electrolyte shifts, which may contribute to arrhythmias and sudden death. Controversies exist about the optimal electrolyte concentration in the dialysate; specifically, it is unclear whether patient outcomes differ among those treated with a dialysate potassium concentration of 3 mEq/L compared to 2 mEq/L.
  
  
  METHODS
  Prospective cohort study.
  
  
  METHODS
  55,183 patients from 20 countries in the Dialysis Outcomes and Practice Patterns Study (DOPPS) phases 1 to 5 (1996-2015).
  
  
  METHODS
  Dialysate potassium concentration at study entry.
  
  
  RESULTS
  Cox regression was used to estimate the association between dialysate potassium concentration and both all-cause mortality and an arrhythmia composite outcome (arrhythmia-related hospitalization or sudden death), adjusting for potential confounders.
  
  
  RESULTS
  During a median follow-up of 16.5 months, 24% of patients died and 7% had an arrhythmia composite outcome. No meaningful difference in clinical outcomes was observed for patients treated with a dialysate potassium concentration of 3 versus 2 mEq/L (adjusted HRs were 0.96 [95% CI, 0.91-1.01] for mortality and 0.98 [95% CI, 0.88-1.08] for arrhythmia composite). Results were similar across predialysis serum potassium levels. As in prior studies, higher serum potassium level was associated with adverse outcomes. However, dialysate potassium concentration had only minimal impact on serum potassium level measured predialysis (+0.09 [95% CI, 0.05-0.14] mEq/L serum potassium per 1 mEq/L greater dialysate potassium concentration).
  
  
  CONCLUSIONS
  Data were not available for delivered (vs prescribed) dialysate potassium concentration and postdialysis serum potassium level; possible unmeasured confounding.
  
  
  CONCLUSIONS
  In combination, these results suggest that approaches other than altering dialysate potassium concentration (eg, education on dietary potassium sources and prescription of potassium-binding medications) may merit further attention to reduce risks associated with high serum potassium levels.
authors.affiliation: Arbor Research Collaborative for Health, Ann Arbor, MI. Electronic address: angelo.karaboyas@arborresearch.org.
authors.forename: Angelo
authors.initials: A
authors.lastname: Karaboyas
authors.affiliation: Arbor Research Collaborative for Health, Ann Arbor, MI.
authors.forename: Jarcy
authors.initials: J
authors.lastname: Zee
authors.affiliation: DaVita Clinical Research, Minneapolis, MN.
authors.forename: Steven M
authors.initials: SM
authors.lastname: Brunelli
authors.affiliation: Fresenius Medical Care North America, Waltham, MA.
authors.forename: Len A
authors.initials: LA
authors.lastname: Usvyat
authors.affiliation: Tufts Medical Center, Boston, MA.
authors.forename: Daniel E
authors.initials: DE
authors.lastname: Weiner
authors.affiliation: Fresenius Medical Care North America, Waltham, MA.
authors.forename: Franklin W
authors.initials: FW
authors.lastname: Maddux
authors.affiliation: DaVita Healthcare Partners, Inc, El Segundo, CA; David Geffen School of Medicine at UCLA, Los Angeles, CA.
authors.forename: Allen R
authors.initials: AR
authors.lastname: Nissenson
authors.affiliation: Cliniques Universitaires Saint-Luc, Université Catholique de Louvain, Brussels, Belgium.
authors.forename: Michel
authors.initials: M
authors.lastname: Jadoul
authors.affiliation: Alessandro Manzoni Hospital, Lecco, Italy.
authors.forename: Francesco
authors.initials: F
authors.lastname: Locatelli
authors.affiliation: Baylor College of Medicine, Houston, TX.
authors.forename: Wolfgang C
authors.initials: WC
authors.lastname: Winkelmayer
authors.affiliation: Arbor Research Collaborative for Health, Ann Arbor, MI; University of Michigan, Ann Arbor, MI.
authors.forename: Friedrich K
authors.initials: FK
authors.lastname: Port
authors.affiliation: Arbor Research Collaborative for Health, Ann Arbor, MI; University of Michigan, Ann Arbor, MI.
authors.forename: Bruce M
authors.initials: BM
authors.lastname: Robinson
authors.affiliation: Arbor Research Collaborative for Health, Ann Arbor, MI; Vanderbilt University, Nashville, TN.
authors.forename: Francesca
authors.initials: F
authors.lastname: Tentori
mesh_terms: D001145:Arrhythmias, Cardiac / Q000097:blood / Q000209:etiology / Q000401:mortality*; D005260:Female; D015312:Hemodialysis Solutions / Q000737:chemistry*; D006801:Humans; D007676:Kidney Failure, Chronic / Q000097:blood / Q000150:complications / Q000401:mortality* / Q000628:therapy*; D008297:Male; D008875:Middle Aged; D017063:Outcome Assessment, Health Care; D011188:Potassium / Q000032:analysis* / Q000097:blood; D011446:Prospective Studies; D006435:Renal Dialysis; D018570:Risk Assessment
chemical_list: D015312:Hemodialysis Solutions; D011188:Potassium
keywords: Dialysate potassium; Dialysis Outcomes and Practice Patterns Study (DOPPS); arrhythmia; cardiac instability; electrolyte shift; end-stage renal disease (ESRD); hemodialysis; hyperkalemia; mortality; potassium gradient; serum potassium; sudden death