Early Plasma Zinc Recovery and Seven-Day Mortality in Adults with Sepsis: A Prospective Cohort Study.

BACKGROUND: Plasma zinc concentrations are altered during critical illness. We determined whether recovery of plasma zinc from admission to day 3 is associated with early mortality in adults with sepsis. METHODS: In this prospective single-center cohort of adults with Sepsis-3 sepsis or septic shock, plasma zinc was measured on admission and on day 3. The main exposure was day-3 zinc adjusted for admission, and the primary outcome was death by day 7 from admission. Zinc trajectories were analyzed using a repeated-measures mixed-effects model, and mortality risk was assessed with a parsimonious 5-predictor Cox model with internal validation. RESULTS: The day-3 cohort included 120 patients, of whom 16 died by day 7. Admission zinc concentrations were similar in survivors and non-survivors, but day-3 zinc was lower in those died (56.05 vs 68.65 ug/dL; p=0.081). The increase in zinc from admission to day 3 was smaller in non-survivors than in survivors (0.80 vs 15.40 ug/dL; p=0.017). Zinc trajectories differed significantly by day-7 outcome (interaction p=0.0022). Higher day-3 zinc was associated with lower mortality (HR per 10 ug/dL 0.77; 95% CI, 0.60-0.97; p=0.028). CONCLUSIONS: Patients with sepsis who remained evaluable through day 3, failure of plasma zinc recovery was associated with higher mortality.