title: Evidence-based incorporation of serum sodium concentration into MELD.
abstract: OBJECTIVE
  Serum sodium (Na) concentrations have been suggested as a useful predictor of mortality in patients with end-stage liver disease awaiting liver transplantation.
  
  
  METHODS
  We evaluated methods to incorporate Na into model for end-stage liver disease (MELD), using a prospective, multicenter database specifically created for validation and refinement of MELD. Adult, primary liver transplant candidates with end-stage liver disease were enrolled.
  
  
  RESULTS
  Complete data were available in 753 patients, in whom the median MELD score was 10.8 and sodium was 137 mEq/L. Low Na (<130 mEq/L) was present in 8% of patients, of whom 90% had ascites. During the study period, 67 patients (9%) died, 243 (32%) underwent transplantation, 73 (10%) were withdrawn, and 370 were still waiting. MELD score and Na, at listing, were significant (both, P < .01) predictors of death within 6 months. After adjustment for MELD score and center, there was a linear increase in the risk of death as Na decreased between 135 and 120 mEq/L. A new score to incorporate Na into MELD was developed: "MELD-Na" = MELD + 1.59 (135 - Na) with maximum and minimum Na of 135 and 120 mEq/L, respectively. In this cohort, "MELD-Na" scores of 20, 30, and 40 were associated with 6%, 16%, and 37% of risk of death within 6 months of listing, respectively. If this new score were used to allocate grafts, it would affect 27% of the transplant recipients.
  
  
  CONCLUSIONS
  We demonstrate an evidence-based method to incorporate Na into MELD, which provides more accurate survival prediction than MELD alone.
authors.affiliation: University of California San Francisco, San Francisco, California, USA.
authors.forename: Scott W
authors.initials: SW
authors.lastname: Biggins
authors.forename: W Ray
authors.initials: WR
authors.lastname: Kim
authors.forename: Norah A
authors.initials: NA
authors.lastname: Terrault
authors.forename: Sammy
authors.initials: S
authors.lastname: Saab
authors.forename: Vijay
authors.initials: V
authors.lastname: Balan
authors.forename: Thomas
authors.initials: T
authors.lastname: Schiano
authors.forename: Joanne
authors.initials: J
authors.lastname: Benson
authors.forename: Terry
authors.initials: T
authors.lastname: Therneau
authors.forename: Walter
authors.initials: W
authors.lastname: Kremers
authors.forename: Russell
authors.initials: R
authors.lastname: Wiesner
authors.forename: Patrick
authors.initials: P
authors.lastname: Kamath
authors.forename: Goran
authors.initials: G
authors.lastname: Klintmalm
mesh_terms: D000704:Analysis of Variance; D015415:Biomarkers / Q000097:blood; D002423:Cause of Death; D016638:Critical Illness; D019317:Evidence-Based Medicine; D005260:Female; D006801:Humans; D007010:Hyponatremia / Q000175:diagnosis*; D017093:Liver Failure / Q000175:diagnosis* / Q000401:mortality* / Q000601:surgery; D008111:Liver Function Tests; D016031:Liver Transplantation; D008297:Male; D011237:Predictive Value of Tests; D016016:Proportional Hazards Models; D011446:Prospective Studies; D018570:Risk Assessment; D012680:Sensitivity and Specificity; D012964:Sodium / Q000097:blood* / Q000378:metabolism; D016019:Survival Analysis; D014850:Waiting Lists
chemical_list: D015415:Biomarkers; D012964:Sodium