The Use of Oral Anticoagulation Is Not Associated With a Reduced Risk of Mortality in Patients With COVID-19: A Systematic Review and Meta-Analysis of Cohort Studies

Impact of prior oral anticoagulation therapies on post-discharge outcomes after COVID-19: Results from a global federated health network analysis

BACKGROUND

The impact of chronic oral anticoagulant (OACs) use on long-term post-discharge outcomes after coronavirus disease 2019 (COVID-19) hospitalisation remains unclear. Herein, we compared clinical outcomes up to 2-years after COVID-19 hospitalisation between patients on vitamin K antagonists (VKAs), direct-acting OACs (DOACs) and no OAC therapy.

METHODS

Data from TriNetX, a global federated health research network, were used. Adult patients on VKAs, DOACs or no OAC therapy at diagnosis of COVID-19 between 20 January 2020 and 31 December 2021, who were hospitalised for COVID-19, were included. The primary outcomes were all-cause mortality, ischaemic stroke/transient ischaemic attack (TIA)/systemic embolism (SE) and the composite of intracranial haemorrhage (ICH)/gastrointestinal bleeding, at 2 years after COVID-19 hospitalisation.

RESULTS

We included 110,834 patients with COVID-19. Following propensity score matching (PSM), we identified a decreased mortality risk in DOAC-treated patients compared to the no OAC cohort (RR .808, 95% CI .751-.870). A higher risk of ischaemic stroke/TIA/SE was observed in VKA users compared to DOAC users (RR 1.100, 95% CI 1.020-1.220) and in VKA users compared to patients not taking OAC (RR 1.400, 95% CI 1.140-1.720). VKA use was associated with a greater risk of ICH/gastrointestinal bleeding than DOAC users (RR 1.198, 95% CI 1.066-1.347), while DOAC users had a lower risk compared to no OAC-treated patients (RR .840, 95% CI .754-.936).

CONCLUSION

COVID-19 patients taking prior DOACs were associated with lower long-term mortality risk and ICH/gastrointestinal bleeding than patients not taking OAC. Compared to patients on DOACs, VKA users were associated with higher risks of mortality, ischaemic stroke/TIA/SE and ICH/gastrointestinal bleeding.

Anticoagulant therapy in adult with COVID-19: a systematic review and meta-analysis of randomized controlled trial

Background

Blood coagulation dysfunction is a risk factor for adverse outcomes in patients with coronavirus disease 2019 (COVID-19), especially in severe cases. The evidence for the effects of anticoagulation therapy on prognosis of COVID-19 patients and its risk of causing bleeding events is accumulating. Here we conducted a meta-analysis to assess the efficacy and safety of anticoagulants in COVID-19 patients of different severity.

Methods

We searched PubMed, Embase databases, Cochrane Trials, OVID MEDLINE from December 2019 to April 2023. We included randomized controlled trials (RCTs) involving COVID-19 patients over 18 years of age, which explored the effect of anticoagulant and its dose on outcomes including all-cause mortality, bleeding events or thrombotic events. We calculated the risk ratio (RR) and its 95% confidence interval (CI) for each outcome. We also performed subgroup analyses to assess the impact of disease severity, using a fixed-effect model to test for heterogeneity. The risk of bias, publication bias, and the quality of evidence were also evaluated.

Results

A total of 20 RCTs were included for final analysis. When compared with standard care, anticoagulation treatment reduced all-cause mortality (RR 0.47, 95% CI: 0.29-0.76) and thrombotic events (RR 0.35, 95% CI: 0.15-0.83) in the whole population with COVID-19 (n=2,365), without increase in bleeding events (total: RR 1.47, 95% CI: 0.54-4.00). Most of the studies only enrolled non-severe patients (n=2,329), while the number of severe patients (n=36) was scarce. In RCTs compared therapeutical and prophylactic doses of anticoagulants, no significant difference in on all-cause mortality was found in the whole population and non-severe and severe subgroups (total: RR 1.01, 95% CI: 0.92-1.10; non-severe: RR 1.03, 95% CI: 0.81-1.32; severe: RR 1.00, 95% CI: 0.91-1.11). Therapeutical dose reduced risk of thrombotic events (total: RR 0.59, 95% CI: 0.48-0.73; subtotal of non-severe: RR 0.57, 95% CI: 0.39-0.84; Subtotal of severe: RR 0.61, 95% CI: 0.47-0.78), while risk of bleeding was increased (total: RR 1.98, 95% CI: 1.47-2.66; non-severe: RR 2.38, 95% CI: 1.56-3.62; severe: RR 1.63, 95% CI: 1.07-2.47). Study heterogeneity was found only in the analysis of effects of anticoagulants on risk of thrombotic events.

Conclusions

Anticoagulant therapy reduces all-cause mortality and risk of thrombosis in non-severe COVID-19 patients. Therapeutic dose of anticoagulant therapy can be considered in both non-severe and severe COVID-19 patients to reduce thrombosis, but may be associated with increased bleeding events.

Factor Xa inhibitors versus low-molecular-weight heparin for preventing coagulopathy following COVID-19: a systematic review and meta-analysis of randomized controlled trials

Background

Hospitalized patients with COVID-19 have shown a significant occurrence of thromboembolism and a heightened risk of death. It remains unclear whether factor Xa inhibitors are superior to enoxaparin in this context. Hence, there is a need for a direct comparison to assess the preventive effects and safety of factor Xa inhibitors versus enoxaparin in hospitalized COVID-19 patients.

Methods

MEDLINE, Embase, and Cochrane Central databases were searched for randomized controlled trials (RCTs) or retrospective studies that compared the effectiveness or safety of factor Xa inhibitors and enoxaparin in preventing thromboembolism in hospitalized patients with COVID-19. Embolic incidence, incidence of bleeding, and all-cause mortality were among the outcomes of interest. Mantel-Haenszel weighted random-effects model was used to calculate relative risks (RRs) with 95 percent CIs.

Results

The analysis included six RCTs and two retrospective studies containing 4048 patients. Meta-analysis showed a statistically significant reduction among patients on factor Xa inhibitors compared with low-molecular-weight heparin (LMWH) in the embolic incidence [risk ratio (RR) 0.64 (95%, CI 0.42, 0.98); P=0.04, I2=12%]. Upon subgroup analysis by type of study design, no significant reductions were noted in patients on factor Xa inhibitors in RCTs (RR: 0.62; 95% CI: 0.33-1.17; P=0.14) or observational studies (RR: 0.53; 95% CI: 0.23-1.26; P=0.15) when compared with enoxaparin Factor Xa inhibitors were not significantly associated with incidence of bleeding [RR 0.76 (95% CI 0.36, 1.61); P=0.47, I2=0%] or all-cause mortality (RR: 0.81; 95% CI: 0.48-1.36; P=0.43). Consistent results were obtained upon subgroup analysis by the type of study design.

Conclusion

Factor Xa inhibitors are more effective than enoxaparin in preventing thromboembolism among patients with COVID-19 who are not acutely ill and are hospitalized. Additional rigorous RCTs comparing factor Xa inhibitors with enoxaparin are warranted.

Increased Thrombotic Risk in COVID-19: Evidence and Controversy

The pandemic of respiratory disease caused by the novel coronavirus named SARS-CoV-2, which emerged at the end of 2019, is still ongoing [...].

The role of direct oral anticoagulants in the era of COVID-19: are antiviral therapy and pharmacogenetics limiting factors?

In patients with COVID-19, thromboinflammation is one of the main causes of morbidity and mortality, which makes anticoagulation an integral part of treatment. However, pharmacodynamic and pharmacokinetic properties of direct oral anticoagulants (DOACs) limit the use of this class of anticoagulants in COVID-19 patients due to a significant interference with antiviral agents. DOACs use in COVID-19 hospitalized patients is currently not recommended. Furthermore, patients already on oral anticoagulant drugs should be switched to heparin at hospital admission. Nevertheless, outpatients with a confirmed diagnosis of COVID-19 are recommended to continue prior DOAC therapy. More studies are required to clarify the pathogenesis of COVID-19-induced derangement of the coagulation system in order to recommend an appropriate anticoagulant treatment.

The Role of Heparin in COVID-19: An Update after Two Years of Pandemics

Coronavirus disease 2019 (COVID-19) is associated with an increased risk of venous thromboembolism (VTE) and coagulopathy, especially in critically ill patients. Endothelial damage induced by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is emerging as a crucial pathogenetic mechanism for the development of complications in an acute phase of the illness and for several postdischarge sequalae. Heparin has been shown to have a positive impact on COVID-19 due to its anticoagulant function. Moreover, several other biological actions of heparin were postulated: a potential anti-inflammatory and antiviral effect through the main protease (Mpro) and heparansulfate (HS) binding and a protection from the damage of vascular endothelial cells. In this paper, we reviewed available evidence on heparin treatment in COVID-19 acute illness and chronic sequalae, focusing on the difference between prophylactic and therapeutic dosage.

The Impact of Prior Antithrombotic use on Thromboembolic Events in Patients with Cardiovascular Disease and Severe COVID-19 Infection

OBJECTIVE

Our objective in this study was to determine the predictive factors of thromboembolic complications in patients with previous heart disease and severe covid-19 infection and the impact of previous use of antithrombotics on protection against these complications.

METHODS

We conducted a single-center retrospective study of 158 patients with heart disease admitted to an intensive care unit for severe SARS-COV-2 infection. In order to determine the predictive factors, we used logistic regression analysis.

RESULTS

Out of 158 patients, 22 were complicated by a thrombo-embolic event (13.9%), mean age of our population 64.03 (SD = 15.27), with a male predominance of 98 (62%). For the predictive factors of thromboembolic complications, and after multivariate analysis, we find the short duration of hospitalization (OR = 0.92; 95%CI (0.863-0.983), P = .014, previous use of antithrombotic drugs ((OR = 0.288, 95%CI (0.091-0.911), P = .034 for antiplatelet agents) and (OR = 0.322, 95% CI (0, 131-0.851), P = .021) for anticoagulants) as protective factors, and admission thrombocytosis as a risk factor (OR = 4.58, 95%CI (1.2-10.627), P = .021). D-dimer was not detected as a risk factor, and this can be explained by the characteristics of our population. Although prior use of antithrombotic drugs protects against thromboembolic complications during severe infection, there was no benefit in mortality.

CONCLUSION

Prior use of antithrombotic drugs is a protective factor against thromboembolic complications in patients with a history of heart disease but without effect on mortality.