Evaluation of zinc sulfate as an adjunctive therapy in COVID-19 critically ill patients: a two center propensity-score matched study.

BACKGROUND: Zinc is a trace element that plays a role in stimulating innate and acquired immunity. The role of zinc in critically ill patients with COVID-19 remains unclear. This study aims to evaluate the efficacy and safety of zinc sulfate as adjunctive therapy in critically ill patients with COVID-19. METHODS: Patients aged ≥ 18 years with COVID-19 who were admitted to the intensive care unit (ICU) in two tertiary hospitals in Saudi Arabia were retrospectively assessed for zinc use from March 1, 2020 until March 31, 2021. After propensity score matching (1:1 ratio) based on the selected criteria, we assessed the association of zinc used as adjunctive therapy with the 30-day mortality. Secondary outcomes included the in-hospital mortality, ventilator free days, ICU length of stay (LOS), hospital LOS, and complication (s) during ICU stay. RESULTS: A total of 164 patients were included, 82 patients received zinc. Patients who received zinc sulfate as adjunctive therapy have a lower 30-day mortality (HR 0.52, CI 0.29, 0.92; p = 0.03). On the other hand, the in-hospital mortality was not statistically significant between the two groups (HR 0.64, CI 0.37-1.10; p = 0.11). Zinc sulfate use was associated with a lower odds of acute kidney injury development during ICU stay (OR 0.46 CI 0.19-1.06; p = 0.07); however, it did not reach statistical significance. CONCLUSION: The use of zinc sulfate as an additional treatment in critically ill COVID-19 patients may improve survival. Furthermore, zinc supplementation may have a protective effect on the kidneys.

Ascorbic acid as an adjunctive therapy in critically ill patients with COVID-19: a propensity score matched study.

Ascorbic acid represents an appealing option for clinicians to utilize in the context of the global COVID-19 pandemic due to its proposed clinical efficacy, relative safety, and low cost. The aim of this study was to evaluate the efficacy and safety of using ascorbic acid in supplemental doses as adjunctive therapy for patients critically ill with COVID-19. This was a two-center, non-interventional, retrospective cohort study. All critically ill adult patients admitted to ICU with a confirmed COVID-19 diagnosis between March 1st and December 31st, 2020, were included in the final analysis. The study was conducted at two large governmental tertiary hospitals in Saudi Arabia. The purpose was to investigate the clinical outcomes of low-dose ascorbic acid as adjunctive therapy in COVID-19 after propensity score matching using baseline severity scores, systematic use of corticosteroids, and study centers. A number of 739 patients were included in this study, among whom 296 patients were included after propensity score matching. There was no association between the administration of ascorbic acid and in-hospital mortality or the 30-day mortality [OR (95% CI) 0.77 (0.47, 1.23), p value = 0.27 and OR (95% CI) 0.73 (0.43, 1.20), p value = 0.21, respectively]. Using ascorbic acid was associated with a lower incidence of thrombosis compared with the non-ascorbic-acid group [6.1% vs. 13% respectively; OR (95% CI) 0.42 (0.184, 0.937), p value = 0.03]. Low dose of ascorbic acid as an adjunctive therapy in COVID-19 critically ill patients was not associated with mortality benefits, but it was associated with a lower incidence of thrombosis. Further studies are required to confirm these findings.