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

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. 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. 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). 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.