Efficacy of different anticoagulant doses for patients with COVID-19: a systematic review and network meta-analysis.

purposeAs no reported randomized control trials (RCTs) directly compare the three administration doses of anticoagulants (prophylactic dose, treatment dose, and no treatment), the most recommended dose to be administered to patients with coronavirus disease 2019 (COVID-19) remains unclear. The purpose of this study was to examine the effects of anticoagulant doses administered to patients with COVID-19, using a network meta-analysis (NMA) including high-quality studies.

methodsAll eligible trials from the Cochrane Central Register of Controlled Trials, MEDLINE, and Clinicaltrials.gov were included. We included RCTs and observational studies adjusted for covariates for patients aged ≥ 18 years and hospitalized due to objectively confirmed COVID-19. The main study outcome was mortality.

resultsIn patients with moderate COVID-19, the prophylactic (relative risk (RR) 0.64 [95% confidence interval (CI) 0.52-0.80]) and treatment dose (RR 0.57 [95% CI 0.45-0.72] were associated with a lower risk of short-term mortality than that with no anticoagulant treatment. However, the prophylactic and treatment dose groups were not significantly different. The hierarchy for efficacy in reducing short-term mortality was treatment dose (P score 92.4) > prophylactic dose (57.6) > no treatment (0.0). In patients with severe COVID-19, due to the absence of trials with the no-treatment group, NMA could not be conducted. However, pairwise comparison did not show a significant difference between the prophylactic and treatment dose groups.

conclusionsTreatment and prophylactic doses of anticoagulants showed similar effects on mortality; however, the treatment dose is preferred over the prophylactic dose for patients with both moderate and severe COVID-19. TRIAL REGISTRATION NUMBER AND REGISTRATION DATES: PROSPERO (registration number: CRD42021245308, 05/21/2021).