Association of serum zinc levels with liver function and survival in patients awaiting liver transplantation.

ABSTRACT

PURPOSE: Zinc is an important trace element with catalytic and defensive functions. We assessed the impact of zinc deficiency in patients with end-stage liver disease awaiting liver transplantation. METHODS: Serum zinc levels were measured at the time of evaluation for liver transplantation (n = 368). Patients were dichotomized in two groups based on low and normal zinc serum levels. RESULTS: Serum zinc levels are tightly associated with liver function as patients with low zinc levels (n = 226) had a higher Model for End-Stage Liver Disease (MELD) score (15.0 [5.0-40.0]) than patients with normal zinc (n = 142) levels (9.0 [6.0-34.0]; p < 0.00). Multivariate analysis demonstrated that serum zinc levels function as an independent predictor of hepatic decompensation (hydropic decompensation odds ratio [OR] 0.82; 95% confidence interval [CI] 0.70-0.96; p = 0.015; hepatic encephalopathy OR 0.80; 95% CI 0.71-0.90; p = 0.000; spontaneous bacterial peritonitis OR 0.85; 95% CI 0.72-1.00; p = 0.047; hepatorenal syndrome OR 0.83; 95% CI 0.72-0.95; p = 0.011). Actuarial survival free of liver transplantation was reduced for low-zinc patients (26.7 ± 4.0 months; 95% CI 18.8-34.6) compared to patients with normal zinc levels (30.9 ± 3.0 months; 95% CI 24.9-36.9; p = 0.008). Reduction of zinc levels for patients on the transplantation list resulted in a 28.3-fold increased risk of death/liver transplantation (95% CI 3.2-244.8, p < 0.001). CONCLUSIONS: Serum zinc levels are associated with reduced survival in end-stage liver disease patients. Whether or not zinc supplementation might be beneficial for patients on a liver transplantation list requires further study.