Updated meta-analysis of randomized controlled trials on the safety and efficacy of different prophylactic anticoagulation dosing regimens in non-critically ill hospitalized patients with COVID-19

COVID-19-Associated Pulmonary Embolism: Review of the Pathophysiology, Epidemiology, Prevention, Diagnosis, and Treatment

COVID-19 is associated with endothelial activation in the setting of a potent inflammatory reaction and a hypercoagulable state. The end result of this thromboinflammatory state is an excess in thrombotic events, in particular venous thromboembolism. Pulmonary embolism (PE) has been of special interest in patients with COVID-19 given its association with respiratory deterioration, increased risk of intensive care unit admission, and prolonged hospital stay. The pathophysiology and clinical characteristics of COVID-19-associated PE may differ from the conventional non-COVID-19-associated PE. In addition to embolic events from deep vein thrombi, in situ pulmonary thrombosis, particularly in smaller vascular beds, may be relevant in patients with COVID-19. Appropriate prevention of thrombotic events in COVID-19 has therefore become of critical interest. Several changes in viral biology, vaccination, and treatment management during the pandemic may have resulted in changes in incidence trends. This review provides an overview of the pathophysiology, epidemiology, clinical characteristics, and risk factors of COVID-19-associated PE. Furthermore, we briefly summarize the results from randomized controlled trials of preventive antithrombotic therapies in COVID-19, focusing on their findings related to PE. We discuss the acute treatment of COVID-19-associated PE, which is substantially similar to the management of conventional non-COVID-19 PE. Ultimately, we comment on the current knowledge gaps in the evidence and the future directions in the treatment and follow-up of COVID-19-associated PE, including long-term management, and its possible association with long-COVID.

The effect of anti-coagulation dosage on the outcome of hospitalized COVID-19 patients in Ethiopia: a multi-center retrospective cohort study

BACKGROUND

Studies have indicated that hospitalized COVID-19 patients benefit from anticoagulation therapy in terms of survival; however, there is an ongoing controversy over the optimum anticoagulant dosage. This study aimed to compare clinical outcomes between patients who received prophylactic anticoagulation and those who received therapeutic anticoagulation.

METHODS

A multi-center retrospective cohort study was conducted to determine the impact of anticoagulation dosage in hospitalized COVID-19 patients in Ethiopia. The primary outcome measure was in-hospital mortality, and it was assessed using multivariable binary logistic regression and covariate-adjusted Cox Proportional Hazard model. For critical and severe COVID-19 patients, subgroup analyses were performed using multivariable binary logistic regression model and multivariable Cox regression models.

RESULT

A total of 472 hospitalized COVID-19 patients were included in this study, of whom 235 (49.8%) received therapeutic anticoagulation and 237 (50.2%) received prophylactic dose. The demographic and baseline clinical characteristics were roughly similar between the groups. After adjustment for several confounders, in critical COVID-19 subgroup, therapeutic dose of anticoagulation was significantly associated with a higher inpatient mortality (AOR 2.27, 95% CI, 1.18-4.35, p = 0.013), whereas in severe COVID-19 subgroup, anticoagulation dosage was not associated with inpatient mortality (OR, 1.02, 95% CI, 0.45 - 2.33, p = 0.958). In severe COVID-19 patient group however, the incidence of thrombosis was slightly lower in the therapeutic group as compared with prophylactic group although the difference was not statistically significant (AOR 0.15, 95% CI, 0.02 - 1.20, p = 0.073). Although there were only six major bleeding events in this study, all these were recorded from patients in the therapeutic subgroup, making the difference statistically significant (p = 0.013).

CONCLUSION

Although this study is limited by its observational design, our results are not consistent with current recommendations on anti-coagulation dose for hospitalized patients with COVID-19, necessitating the need for RCT in resource limited settings.

The Conundrum of Anticoagulation for Hospitalized Patients with Covid-19

Thrombosis in patients with coronavirus disease 2019 (Covid-19) is driven by complex interactions between immune, complement, fibrinolytic, endothelial, and coagulation systems.1 In addition to venous thromboembolism (VTE), microthrombi have also been implicated in contributing to end-organ damage, such as acute respiratory distress syndrome and kidney dysfunction, as well as to overall mortality.1 As available therapies, variants, and vaccines have evolved, so have reported rates of VTE attributable to Covid-19.

One-year cardiovascular outcomes after coronavirus disease 2019: The cardiovascular COVID-19 registry

BACKGROUND

The long-term cardiovascular (CV) outcomes of COVID-19 have not been fully explored.

METHODS

This was an international, multicenter, retrospective cohort study conducted between February and December 2020. Consecutive patients ≥18 years who underwent a real-time reverse transcriptase-polymerase chain reaction (RT-PCR) for SARS-CoV2 were included. Patients were classified into two cohorts depending on the nasopharyngeal swab result and clinical status: confirmed COVID-19 (positive RT-PCR) and control (without suggestive symptoms and negative RT-PCR). Data were obtained from electronic records, and clinical follow-up was performed at 1-year. The primary outcome was CV death at 1-year. Secondary outcomes included arterial thrombotic events (ATE), venous thromboembolism (VTE), and serious cardiac arrhythmias. An independent clinical event committee adjudicated events. A Cox proportional hazards model adjusted for all baseline characteristics was used for comparing outcomes between groups. A prespecified landmark analysis was performed to assess events during the post-acute phase (31-365 days).

RESULTS

A total of 4,427 patients were included: 3,578 (80.8%) in the COVID-19 and 849 (19.2%) control cohorts. At one year, there were no significant differences in the primary endpoint of CV death between the COVID-19 and control cohorts (1.4% vs. 0.8%; HRadj 1.28 [0.56-2.91]; p = 0.555), but there was a higher risk of all-cause death (17.8% vs. 4.0%; HRadj 2.82 [1.99-4.0]; p = 0.001). COVID-19 cohort had higher rates of ATE (2.5% vs. 0.8%, HRadj 2.26 [1.02-4.99]; p = 0.044), VTE (3.7% vs. 0.4%, HRadj 9.33 [2.93-29.70]; p = 0.001), and serious cardiac arrhythmias (2.5% vs. 0.6%, HRadj 3.37 [1.35-8.46]; p = 0.010). During the post-acute phase, there were no significant differences in CV death (0.6% vs. 0.7%; HRadj 0.67 [0.25-1.80]; p = 0.425), but there was a higher risk of deep vein thrombosis (0.6% vs. 0.0%; p = 0.028). Re-hospitalization rate was lower in the COVID-19 cohort compared to the control cohort (13.9% vs. 20.6%; p = 0.001).

CONCLUSIONS

At 1-year, patients with COVID-19 experienced an increased risk of all-cause death and adverse CV events, including ATE, VTE, and serious cardiac arrhythmias, but not CV death.

STUDY REGISTRATION

URL: https://www.clinicaltrials.gov. Unique identifier: NCT04359927.

Investigating the association between IL-6 antagonist therapy and blood coagulation in critically ill patients with COVID-19: a protocol for a prospective, observational, multicentre study

INTRODUCTION

Hypercoagulation is one the main features of COVID-19. It is induced by the hyperinflammatory response that shifts the balance of haemostasis towards pro-coagulation. Interleukin-6 (IL-6) antagonist therapy has been recommended in certain subgroups of critically ill patients with COVID-19 to modulate inflammatory response. The interaction between immune response and haemostasis is well recognised. Therefore, our objective is to evaluate whether the modulation of the inflammatory response by IL-6 antagonist inflicts any changes in whole blood coagulation as assessed by viscoelastic methods in critically ill patients with COVID-19.

METHODS AND ANALYSIS

In this prospective observational study, we are going to collect data on inflammatory parameters and blood coagulation using the ClotPro^® device. The primary outcome is the change of the fibrinolytic system measured by the Lysis Time and Lysis onset time before and after immunomodulation therapy. Data will be collected before the IL-6 antagonist administration at baseline (T₀) then after 24, 48 hours, then on day 5 and 7 (T_1-4, respectively). Secondary outcomes include changes in other parameters related to inflammation, blood coagulation and biomarkers of endothelial injury.

ETHICS AND DISSEMINATION

Ethical approval was given by the Medical Research Council of Hungary (1405-3/2022/EÜG). All participants provided written consent. The results of the study will be disseminated through peer-reviewed journals.

TRIAL REGISTRATION NUMBER

NCT05218369; Clinicaltrials.gov.

Anticoagulation in hospitalized patients with COVID-19

Coronavirus disease-19 (COVID-19) includes a thromboinflammatory syndrome that may manifest with microvascular and macrovascular thrombosis. Patients with COVID-19 have a higher incidence of venous thromboembolism than other hospitalized patients. Three randomized control trials suggesting benefit of therapeutic heparin in hospitalized noncritically ill patients with COVID-19 have led to conditional guideline recommendations for this treatment. By contrast, prophylactic-dose heparin is recommended for critically ill patients. Unprecedented collaboration and rapidly funded research have improved care of hospitalized patients with COVID-19.

Effect of therapeutic versus prophylactic anticoagulation therapy on clinical outcomes in COVID-19 patients: a systematic review with an updated meta-analysis

Background

Previous studies demonstrate a reduced risk of thrombosis and mortality with anticoagulant treatment in patients with COVID-19 than in those without anticoagulation treatment. However, an open question regarding the efficacy and safety of therapeutic anticoagulation (T-AC) versus a lower dose, prophylaxis anticoagulation (P-AC) in COVID-19 patients is still controversial.

Methods

We systematically reviewed currently available randomized clinical trials (RCTs) and observational studies (OBs) from January 8, 2019, to January 8, 2022, and compared prophylactic and therapeutic anticoagulant treatment in COVID-19 patients. The primary outcomes were risk of mortality, major bleeding, and the secondary outcomes included venous and arterial thromboembolism. Subgroup analysis was also performed between critically ill and non-critically ill patients with COVID-19 and between patients with higher and lower levels of D-dimer. Sensitivity analysis was performed to decrease the bias and the impact of population heterogeneity.

Results

We identified 11 RCTs and 17 OBs fulfilling our inclusion criteria. In the RCTs analyses, there was no statistically significant difference in the relative risk of mortality between COVID-19 patients with T-AC treatment and those treated with P-AC (RR 0.95, 95% CI, 0.78–1.15, P = 0.60). Similar results were also found in the OBs analyses (RR 1.21, 95% CI, 0.98–1.49, P = 0.08). The pooling meta-analysis using a random-effects model combined with effect sizes showed that in the RCTs and OBs analyses, patients with COVID-19 who received T-AC treatment had a significantly higher relative risk of the major bleeding event than those with P-AC treatment in COVID-19 patients (RCTs: RR 1.76, 95% CI, 1.19–2.62, P = 0.005; OBs: RR 2.39, 95% CI, 1.56–3.68, P < 0.0001). Compared with P-AC treatment in COVID-19 patients, patients with T-AC treatment significantly reduced the incidence of venous thromboembolism (RR 0.51, 95% CI, 0.39–0.67, P<0.00001), but it is not associated with arterial thrombosis events (RR 0.97, 95% CI, 0.66–1.42, P = 0.87). The subgroup analysis of OBs shows that the mortality risk significantly reduces in critically ill COVID-19 patients treated with T-AC compared with those with P-AC treatment (RR 0.58, 95% CI, 0.39–0.86, P = 0.007), while the mortality risk significantly increases in non-critically ill COVID-19 patients treated with T-AC (RR 1.56, 95% CI, 1.34–1.80, P < 0.00001). In addition, T-AC treatment does not reduce the risk of mortality in COVID-19 patients with high d-dimer levels in RCTs. Finally, the overall sensitivity analysis after excluding two RCTs studies remains consistent with the previous results.

Conclusions

In our integrated analysis of included RCTs and OBs, there is no significant difference between the mortality of T-AC and P-AC treatment in unselected patients with COVID-19. T-AC treatment in COVID-19 patients significantly reduced the incidence of venous thromboembolism but showed a higher risk of bleeding than those with P-AC treatment. In addition, P-AC treatment was superior to T-AC treatment in non-critically ill COVID-19 patients, the evidence supporting the necessity for T-AC treatment in critically ill COVID-19 patients came only from OBs.

Trial registration

Protocol registration: The protocol was registered at PROSPERO (CRD42021293294).

Graphical abstract

Supplementary Information

The online version contains supplementary material available at 10.1186/s12959-022-00408-9.