Effect of zinc supplement on patients with trauma: A systematic review and meta-analysis

Aims: This study aimed to assess the effect of zinc supplementation, with or without other antioxidants and trace elements, on clinical outcomes in patients with trauma. Methods: A systematic review was conducted for adult patients with acute trauma who had been admitted to the hospital. Those who sustained burn injuries were excluded. Studies in PubMed, Web of Science, and Embase from 1990 to 2022 regarding the additional nutrition supplementation of zinc to patients, either in a single-agent or combined regimen, were included. Comparisons were made between the zinc supplement group and those who received a placebo or regular treatment. Results: The primary outcomes of the study were mortality rate, length of hospital stay, and incidence of pneumonia. Seven studies qualified for the meta-analysis. Of the 594 patients eligible for analysis, 290 and 304 were in the zinc supplementation and control groups, respectively. The meta-analysis revealed that zinc supplementation was associated with a lower risk of pneumonia in patients with acute trauma than in the control group (odds ratio [OR], 0.506; 95% CI = 0.292–0.877; P = 0.015; heterogeneity, I² = 12.7%). Zinc supplementation did not influence the mortality rate (OR, 0.755; 95% CI = 0.492–1.16; P = 0.612; heterogeneity, I² = 0%) or the length of hospital stay (standard difference in means, −0.24; 95% CI = −0.544 to 0.063; P = 0.121; heterogeneity, I² = 45.0%). Conclusion: Zinc supplementation, with or without other antioxidants and trace elements, in patients with trauma was associated with a lower incidence of pneumonia.