Prognostic value of serum zinc levels in critically ill patients

We investigated the hypothesis that a decline in serum zinc concentrations among critically ill patients is related to mortality, length of stay in the intensive care unit, and Acute Physiology and Chronic Health Evaluation II and Sequential Organ Failure Assessment (SOFA) scores.

All the patients (≥18 years old) presenting to the intensive care unit from September 2009 through November 2009 were enrolled the study. Patients' demographic characteristics and Acute Physiology and Chronic Health Evaluation and SOFA scores were recorded. Blood samples were collected within 24 hours after admission and analyzed for serum zinc, copper, C-reactive protein, and albumin levels. Patients were followed up for mortality and length of stay in the intensive care unit for 28 days.

A total of 36 patients, with a median age of 70.5 years (range, 18-87 years), were enrolled during the study period. Serum zinc levels were found to be inversely correlated with SOFA scores (r = -0.41, P < .01). Patients with SOFA scores of 8 or higher had significantly lower serum zinc levels compared with patients with SOFA scores lower than 8 (6.74 ± 1.63 and 9.17 ± 2.76 μmol/L, respectively; P < .01).

The result of this study supports the fact that organ failure and critical illness lead to a decline in serum zinc concentrations and that administration of zinc may be beneficial for critically ill patients.