Background Whether vitamin C provides any benefit when administered in critically ill patients, including those with coronavirus disease (COVID-19), is controversial. We endeavored to estimate the effect of administration of vitamin C on clinical outcomes of critically ill patients with COVID-19 by performing an observational study and subsequent meta-analysis. Methods Firstly, we conducted an observational study of critically ill patients with laboratory-confirmed COVID-19 who consecutively underwent invasive mechanical ventilation in an academic intensive care unit (ICU) during the second pandemic wave. We compared all-cause mortality of patients receiving vitamin C (“vitamin C” group) or not (“control” group) on top of standard-of-care. Subsequently, we systematically searched PubMed and CENTRAL for relevant studies, which reported on all-cause mortality (primary outcome) and/or morbidity of critically ill patients with COVID-19 receiving vitamin C or not treatment. Pooled risk ratio (RR) and 95% confidence intervals (CI) were calculated using a random effects model. The meta-analysis was registered with PROSPERO. Results In the observational study, baseline characteristics were comparable between the two groups. Mortality was 20.0% (2/10) in the vitamin C group vs. 47.6% (49/103; p = 0.11) in the control group. Subsequently, the meta-analysis included 11 studies (6 observational; five randomized controlled trials) enrolling 1,807 critically ill patients with COVID-19. Mortality of patients receiving vitamin C on top of standard-of-care was not lower than patients receiving standard-of-care alone (25.8 vs. 34.7%; RR 0.85, 95% CI 0.57–1.26; p = 0.42). Conclusions After combining results of our observational cohort with those of relevant studies into a meta-analysis of data from 1,807 patients, we found that administration vitamin C as opposed to standard-of-care alone might not be associated with lower of mortality among critically ill patients with COVID-19. Additional evidence is anticipated from relevant large randomized controlled trials which are currently underway. Systematic Review Registration https://www.crd.york.ac.uk/prospero/ , identifier: CRD42021276655.
【저자키워드】 coronavirus, acute respiratory distress syndrome, mechanical ventilation, Pneumonia, intensive care unit, Acute respiratory failure, 【초록키워드】 COVID-19, Randomized controlled trial, Treatment, coronavirus disease, Meta-analysis, review, pandemic, Randomized controlled trials, Mortality, intensive care, Vitamin C, risk, ICU, Clinical outcome, Registration, Cohort, morbidity, Patient, patients, critically ill patients, Evidence, Invasive mechanical ventilation, administration, Critically ill patient, Primary outcome, control group, two groups, 95% CI, 95% confidence interval, baseline characteristics, all-cause mortality, Registered, laboratory-confirmed, random effect, Standard-of-care, Administered, FIVE, benefit, Result, reported, subsequent, conducted, receiving, calculated, provide, searched, comparable, anticipated, with COVID-19, 【제목키워드】 clinical, Vitamin, Effect, Ill,