title: Dialysate sodium prescription and blood pressure in hemodialysis patients.
abstract: BACKGROUND
  Diffusive sodium removal has been recommended to control hypertension in hemodialysis patients. Recent evidence on hospitalizations and mortality, however, challenged the benefit of lower dialysate sodium prescriptions and ignited a debate in the dialysis community. We therefore studied the relationship between dialysate sodium and blood pressure over the longer term.
  
  
  METHODS
  We used multiply adjusted linear mixed models to estimate the association between dialysate sodium and predialysis systolic blood pressure (SBP) as well as change in SBP (delta SBP; postdialysis minus predialysis) in 23,962 patients from the international Dialysis Outcomes and Practice Patterns Study.
  
  
  RESULTS
  We found that 43% of hemodialysis facilities had variable (individualized) dialysate sodium prescriptions (125-155 mEq/L), whereas 57% had uniform dialysate sodium prescriptions (135-145 mEq/L) for ≥90% patients. Between-group comparisons of these 2 facility types suggested that dialysate sodium, when variably prescribed, might have been used to modify predialysis SBP (P interaction = 0.01) and perhaps delta SBP levels (P interaction = 0.08). Within facilities not prone to indication bias, because dialysate sodium was not variable, higher uniform dialysate sodium (per 2 mEq/L) was associated with slightly higher SBP (+0.9 mm Hg, 95% confidence interval (CI) = 0.1-1.6 among all patients; +1.7 mm Hg, 95% CI = 0.1-3.2 among patients not treated with blood pressure medication) and no increase in delta SBP.
  
  
  CONCLUSIONS
  Patients assigned to hemodialysis facilities with uniformly higher dialysate sodium do not have markedly higher predialysis SBP, providing rather limited support for lowering dialysate sodium to control hypertension, particularly in view of hospitalization and mortality risks associated with lower dialysate sodium.
authors.affiliation: Department of Internal Medicine III-Nephrology, Medical University of Vienna, Vienna, Austria;
authors.forename: Manfred
authors.initials: M
authors.lastname: Hecking
authors.affiliation: Arbor Research Collaborative for Health, Ann Arbor, MI;
authors.forename: Angelo
authors.initials: A
authors.lastname: Karaboyas
authors.affiliation: Birmingham Heartlands Hospital, Birmingham;
authors.forename: Hugh
authors.initials: H
authors.lastname: Rayner
authors.affiliation: Department of Internal Medicine-Nephrology, University of Michigan, Ann Arbor, MI; Kidney Epidemiology and Cost Center, University of Michigan, Ann Arbor, MI;
authors.forename: Rajiv
authors.initials: R
authors.lastname: Saran
authors.affiliation: Department of Family Medicine, University of Michigan, Ann Arbor, MI; Department of Biostatistics, University of Michigan, Ann Arbor, MI;
authors.forename: Ananda
authors.initials: A
authors.lastname: Sen
authors.affiliation: Department of Metabolism, Endocrinology, and Molecular Medicine, Osaka City University Graduate School of Medicine, Osaka, Japan;
authors.forename: Masaaki
authors.initials: M
authors.lastname: Inaba
authors.affiliation: Department of Nephrology, University of Heidelberg , Heidelberg, Germany.
authors.forename: Jürgen
authors.initials: J
authors.lastname: Bommer
authors.affiliation: Department of Internal Medicine III-Nephrology, Medical University of Vienna, Vienna, Austria;
authors.forename: Walter H
authors.initials: WH
authors.lastname: Hörl
authors.affiliation: Arbor Research Collaborative for Health, Ann Arbor, MI;
authors.forename: Ronald L
authors.initials: RL
authors.lastname: Pisoni
authors.affiliation: Arbor Research Collaborative for Health, Ann Arbor, MI;
authors.forename: Bruce M
authors.initials: BM
authors.lastname: Robinson
authors.affiliation: Department of Internal Medicine III-Nephrology, Medical University of Vienna, Vienna, Austria;
authors.forename: Gere
authors.initials: G
authors.lastname: Sunder-Plassmann
authors.affiliation: Arbor Research Collaborative for Health, Ann Arbor, MI; friedrich.port@arborresearch.org.
authors.forename: Friedrich K
authors.initials: FK
authors.lastname: Port
mesh_terms: D000959:Antihypertensive Agents / Q000627:therapeutic use; D001794:Blood Pressure / Q000187:drug effects; D015314:Dialysis Solutions / Q000009:adverse effects / Q000627:therapeutic use*; D005260:Female; D006801:Humans; D006973:Hypertension / Q000097:blood / Q000175:diagnosis / Q000188:drug therapy / Q000453:epidemiology / Q000503:physiopathology*; D007674:Kidney Diseases / Q000097:blood / Q000175:diagnosis / Q000453:epidemiology / Q000503:physiopathology / Q000628:therapy*; D016014:Linear Models; D008297:Male; D015999:Multivariate Analysis; D010818:Practice Patterns, Physicians'; D055656:Prescriptions; D015995:Prevalence; D011446:Prospective Studies; D006435:Renal Dialysis / Q000009:adverse effects; D012307:Risk Factors; D012964:Sodium / Q000009:adverse effects / Q000097:blood / Q000627:therapeutic use*; D013997:Time Factors; D016896:Treatment Outcome
chemical_list: D000959:Antihypertensive Agents; D015314:Dialysis Solutions; D012964:Sodium
keywords: blood pressure; dialysate sodium; hemodialysis; hypertension; intradialytic hypotension; systolic blood pressure.