title: Addition of serum sodium into the MELD score predicts waiting list mortality better than MELD alone.
abstract: In this study, we investigated the prognostic value of serum sodium and hyponatremia (< or =130 mEq/L) in 262 cirrhotic patients consecutively listed, 19 of which died (7%), 175 survived (67%), and 68 underwent liver transplantation (26%) during 3 months of follow-up. Hyponatremia was present in 63% of patients who died, compared to 13% of those who survived (P < .001), whereas the proportion with elevated creatinine (> or =1.4 mg/dL) was low and similar in both groups (10.5 vs. 3%). Prevalence of hyponatremia was higher than that of elevated serum creatinine across all model for end-stage liver disease (MELD) categories. Using logistic regression, hyponatremia and serum sodium were significant predictors of mortality with concordance statistics (c-statistics) .753 for hyponatremia, .784 for sodium, .894 for MELD, .905 for MELD plus hyponatremia (P = .006 vs. MELD alone), and .908 for MELD plus serum sodium (P = .026 vs. MELD alone). Risk of death across all MELD scores was higher for patients with hyponatremia than without hyponatremia. Cox regression considering data within 6 months of follow-up yielded qualitatively similar results, with hyponatremia being a significant predictor of greater mortality risk with an odds ratio of 2.65 (P = .015). Each increase of 1 mEq/L of serum sodium level was associated with a decreased odds ratio of .95 (P = .048). Our results indicate that hyponatremia appears to be an earlier and more sensitive marker than serum creatinine to detect renal impairment and / or circulatory dysfunction in patients with advanced cirrhosis. In conclusion, addition of serum sodium to MELD identified a subgroup of patients with poor outcome in a more efficient way than MELD alone and significantly increased the efficacy of the score to predict waitlist mortality.
authors.affiliation: Liver Unit, Fundación Favaloro, Buenos Aires, Argentina. aruf@ffavaloro.org
authors.forename: Andres E
authors.initials: AE
authors.lastname: Ruf
authors.forename: Walter K
authors.initials: WK
authors.lastname: Kremers
authors.forename: Lila L
authors.initials: LL
authors.lastname: Chavez
authors.forename: Valeria I
authors.initials: VI
authors.lastname: Descalzi
authors.forename: Luis G
authors.initials: LG
authors.lastname: Podesta
authors.forename: Federico G
authors.initials: FG
authors.lastname: Villamil
mesh_terms: D000328:Adult; D001663:Bilirubin / Q000097:blood; D006801:Humans; D007010:Hyponatremia / Q000453:epidemiology; D019934:International Normalized Ratio; D008103:Liver Cirrhosis / Q000601:surgery*; D016031:Liver Transplantation / Q000401:mortality / Q000502:physiology*; D011237:Predictive Value of Tests; D015203:Reproducibility of Results; D012720:Severity of Illness Index; D012964:Sodium / Q000097:blood*; D016019:Survival Analysis; D013997:Time Factors; D014850:Waiting Lists
chemical_list: D012964:Sodium; D001663:Bilirubin