Randomized clinical trial to evaluate a routine full anticoagulation Strategy in Patients with Coronavirus Infection (SARS-CoV2) admitted to hospital: Rationale and design of the ACTION (AntiCoagulaTlon cOroNavirus)-Coalition IV trial

COVID-19 Diagnosis, Oral Anticoagulation, and Stroke Risk in Patients with Atrial Fibrillation

BACKGROUND

Coronavirus disease 2019 (COVID-19) has been associated with an increased risk of stroke. It remains unclear whether the risk of stroke associated with a diagnosis of COVID-19 differed with oral anticoagulation (OAC) use. The aim of this study was to evaluate the association between COVID-19 infection, OAC use, and stroke in patients with atrial fibrillation (AF).

METHODS

A retrospective cohort study was conducted in individuals with established AF using data from Optum's deidentified Clinformatics® Data Mart Database. Cox proportional hazard models with time-dependent variables were employed to assess the association between possession of OAC, COVID-19 diagnosis in both inpatient and outpatient setting, and time to ischemic stroke.

RESULTS

A total of 561,758 individuals aged 77 ± 10 were included in the study, with a mean follow up time of 1.3 years. OAC use was associated with a reduced stroke risk [hazard ratio (HR) 0.85, 95% confidence interval (CI) 0.82-0.88]. COVID-19 infection was associated with an increased risk of stroke (HR 2.11, 95% CI 1.87-2.38); this increased risk was particularly pronounced for patients diagnosed with an inpatient diagnosis of COVID-19 (HR 3.95, 95% CI 3.33-4.68). There was no significant interaction between OAC use and COVID-19 diagnosis (p value = 0.96). As a result, the relative increase in stroke risk associated with COVID-19 did not differ between patients on OAC (HR 2.12; 95% CI 1.71-2.62) and those not on OAC (HR 2.11; 95% CI 1.83-2.43).

CONCLUSION

In a nationwide sample of patients with established AF, we found the relative increase in stroke risk associated with COVID-19 was independent of OAC use.

Predictors of bleeding and thrombotic events among patients admitted to the hospital with COVID-19 and elevated D-dimer: insights from the ACTION randomized clinical trial

Therapeutic anticoagulation showed inconsistent results in hospitalized patients with COVID-19 and selection of the best patients to use this strategy still a challenge balancing the risk of thrombotic and hemorrhagic outcomes. The present post-hoc analysis of the ACTION trial evaluated the variables independently associated with both bleeding events (major bleeding or clinically relevant non-major bleeding) and the composite outcomes thrombotic events (venous thromboembolism, myocardial infarction, stroke, systemic embolism, or major adverse limb events). Variables were assessed one by one with independent logistic regressions and final models were chosen based on Akaike information criteria. The model for bleeding events showed an area under the curve of 0.63 (95% confidence interval [CI] 0.53 to 0.73), while the model for thrombotic events had an area under the curve of 0.72 (95% CI 0.65 to 0.79). Non-invasive respiratory support was associated with thrombotic but not bleeding events, while invasive ventilation was associated with both outcomes (Odds Ratio of 7.03 [95 CI% 1.95 to 25.18] for thrombotic and 3.14 [95% CI 1.11 to 8.84] for bleeding events). Beyond respiratory support, creatinine level (Odds Ratio [OR] 1.01 95% CI 1.00 to 1.02 for every 1.0 mg/dL) and history of coronary disease (OR 3.67; 95% CI 1.32 to 10.29) were also independently associated to the risk of thrombotic events. Non-invasive respiratory support, history of coronary disease, and creatinine level may help to identify hospitalized COVID-19 patients at higher risk of thrombotic complications.ClinicalTrials.gov: NCT04394377.

Management of severe peri-operative bleeding: Guidelines from the European Society of Anaesthesiology and Intensive Care: Second update 2022

BACKGROUND

Management of peri-operative bleeding is complex and involves multiple assessment tools and strategies to ensure optimal patient care with the goal of reducing morbidity and mortality. These updated guidelines from the European Society of Anaesthesiology and Intensive Care (ESAIC) aim to provide an evidence-based set of recommendations for healthcare professionals to help ensure improved clinical management.

DESIGN

A systematic literature search from 2015 to 2021 of several electronic databases was performed without language restrictions. Grading of Recommendations, Assessment, Development and Evaluation (GRADE) was used to assess the methodological quality of the included studies and to formulate recommendations. A Delphi methodology was used to prepare a clinical practice guideline.

RESULTS

These searches identified 137 999 articles. All articles were assessed, and the existing 2017 guidelines were revised to incorporate new evidence. Sixteen recommendations derived from the systematic literature search, and four clinical guidances retained from previous ESAIC guidelines were formulated. Using the Delphi process on 253 sentences of guidance, strong consensus (>90% agreement) was achieved in 97% and consensus (75 to 90% agreement) in 3%.

DISCUSSION

Peri-operative bleeding management encompasses the patient's journey from the pre-operative state through the postoperative period. Along this journey, many features of the patient's pre-operative coagulation status, underlying comorbidities, general health and the procedures that they are undergoing need to be taken into account. Due to the many important aspects in peri-operative nontrauma bleeding management, guidance as to how best approach and treat each individual patient are key. Understanding which therapeutic approaches are most valuable at each timepoint can only enhance patient care, ensuring the best outcomes by reducing blood loss and, therefore, overall morbidity and mortality.

CONCLUSION

All healthcare professionals involved in the management of patients at risk for surgical bleeding should be aware of the current therapeutic options and approaches that are available to them. These guidelines aim to provide specific guidance for bleeding management in a variety of clinical situations.

Small molecules in the treatment of COVID-19

The outbreak of COVID-19 has become a global crisis, and brought severe disruptions to societies and economies. Until now, effective therapeutics against COVID-19 are in high demand. Along with our improved understanding of the structure, function, and pathogenic process of SARS-CoV-2, many small molecules with potential anti-COVID-19 effects have been developed. So far, several antiviral strategies were explored. Besides directly inhibition of viral proteins such as RdRp and Mpro, interference of host enzymes including ACE2 and proteases, and blocking relevant immunoregulatory pathways represented by JAK/STAT, BTK, NF-κB, and NLRP3 pathways, are regarded feasible in drug development. The development of small molecules to treat COVID-19 has been achieved by several strategies, including computer-aided lead compound design and screening, natural product discovery, drug repurposing, and combination therapy. Several small molecules representative by remdesivir and paxlovid have been proved or authorized emergency use in many countries. And many candidates have entered clinical-trial stage. Nevertheless, due to the epidemiological features and variability issues of SARS-CoV-2, it is necessary to continue exploring novel strategies against COVID-19. This review discusses the current findings in the development of small molecules for COVID-19 treatment. Moreover, their detailed mechanism of action, chemical structures, and preclinical and clinical efficacies are discussed.

Pathophysiological mechanisms of thrombosis in acute and long COVID-19

COVID-19 patients have a high incidence of thrombosis, and thromboembolic complications are associated with severe COVID-19 and high mortality. COVID-19 disease is associated with a hyper-inflammatory response (cytokine storm) mediated by the immune system. However, the role of the inflammatory response in thrombosis remains incompletely understood. In this review, we investigate the crosstalk between inflammation and thrombosis in the context of COVID-19, focusing on the contributions of inflammation to the pathogenesis of thrombosis, and propose combined use of anti-inflammatory and anticoagulant therapeutics. Under inflammatory conditions, the interactions between neutrophils and platelets, platelet activation, monocyte tissue factor expression, microparticle release, and phosphatidylserine (PS) externalization as well as complement activation are collectively involved in immune-thrombosis. Inflammation results in the activation and apoptosis of blood cells, leading to microparticle release and PS externalization on blood cells and microparticles, which significantly enhances the catalytic efficiency of the tenase and prothrombinase complexes, and promotes thrombin-mediated fibrin generation and local blood clot formation. Given the risk of thrombosis in the COVID-19, the importance of antithrombotic therapies has been generally recognized, but certain deficiencies and treatment gaps in remain. Antiplatelet drugs are not in combination with anticoagulant treatments, thus fail to dampen platelet procoagulant activity. Current treatments also do not propose an optimal time for anticoagulation. The efficacy of anticoagulant treatments depends on the time of therapy initiation. The best time for antithrombotic therapy is as early as possible after diagnosis, ideally in the early stage of the disease. We also elaborate on the possible mechanisms of long COVID thromboembolic complications, including persistent inflammation, endothelial injury and dysfunction, and coagulation abnormalities. The above-mentioned contents provide therapeutic strategies for COVID-19 patients and further improve patient outcomes.

Venous Thromboembolic Disease in COVID-19, Pathophysiology, Therapy and Prophylaxis

For over two years, the world has been facing the epidemiological and health challenge of the coronavirus disease 2019 (COVID-19) pandemic, caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. Growing problems are also complications after the development of COVID-19 in the form of post and long- COVID syndromes, posing a challenge for the medical community, both for clinicians and the scientific world. SARS-CoV-2 infection is associated with an increased risk of cardiovascular complications, especially thromboembolic complications, which are associated with both thrombosis of small and very small vessels due to immunothrombosis, and the development of venous thromboembolism. Low molecular wight heparin (LMHW) are the basic agents used in the prevention and treatment of thromboembolic complications in COVID-19. There is still a great deal of controversy regarding both the prevention and treatment of thromboembolic complications, including the prophylaxis dose or the optimal duration of anticoagulant treatment in patients with an episode of venous thromboembolism.

Increased Susceptibility for Thromboembolic Events versus High Bleeding Risk Associated with COVID-19

The infection with the SARS-CoV-2 virus is associated with numerous systemic involvements. Besides the severe respiratory injuries and cardiovascular complications, it became obvious early on that this disease carries an increased risk of thromboembolic events, but a higher propensity for bleedings as well. We researched the medical literature over significant PubMed published articles debating on the prevalence, category of patients, the moment of occurrence, and evolution of venous thromboembolism (VTE), but also of venous and arterial “in situ” thrombosis (AT), and hemorrhagic events as well. Most researchers agree on an increased prevalence of thromboembolic events, ranging between 25 and 31% for VTE, depending on the analyzed population. For AT and hemorrhagic complications lower rates were reported, namely, about 2–3%, respectively, between 4.8 and 8%, occurring mostly in older patients, suffering from moderate/severe forms of COVID-19, with associated comorbidities. It is important to mention that patients suffering from hemorrhages frequently received thromboprophylaxis with anticoagulant drugs. As a consequence of thromboembolic and hemorrhagic complications which are both important negative prognostic factors, the evolution of patients infected with the SARS-CoV-2 virus is aggravated, determining an augmented morbidity and mortality of this population.

The effect of low-dose and high-dose low-molecular-weight-heparin and aspirin thromboprophylaxis on clinical outcome and mortality in critical ill patients with COVID-19: A retrospective cohort study

OBJECTIVES

To assess the effect of different thromboprophylaxis regimens on clinical outcomes and mortality of critical ill patients with coronavirus disease -19 (COVID-19).

METHODS

We investigated the medical records of patients with positive COVID-19 (using polymerase chain reaction test) who were admitted to the intensive care unit (ICU) at Sakarya University Hospital, Sakarya, Turkey, from March 2020 to January 2021. We included patients under anticoagulant therapy in the clinical course. The patients were allocated to 3 groups: Group A - low-dose (prophylactic) low-molecular-weight-heparin (LMWH) therapy, Group B - high-dose (therapeutic) LMWH therapy, and patients that received aspirin additional to the high-dose (therapeutic) LMWH as Group C. Primary outcomes were overall mortality rates and length of stay (LOS) in ICU. Secondary outcomes were rates of major hemorrhagic and thrombotic events.

RESULTS

Records of 475 patients were reviewed and 164 patients were included. No significant difference was detected in mortality rates between groups (p=0.135). Intensive care unit stay was 13 (9-24.5) days in Group A, 11 (8.75-23) days in Group B, and 13 (9-17) days in Group C without a significant difference (p=0.547). No significant difference was detected between groups in terms of thrombotic (p=0.565) and hemorrhagic events (p=0.615).

CONCLUSION

A high-dose anticoagulation therapy and addition of aspirin to LMWH therapy did not decrease the mortality rates and LOS in ICU in critical ill COVİD-19 patients. In addition, it did not increase the incidence of major hemorrhage and major thrombotic events.

Anticoagulants for people hospitalised with COVID-19

BACKGROUND

The primary manifestation of coronavirus disease 2019 (COVID-19) is respiratory insufficiency that can also be related to diffuse pulmonary microthrombosis and thromboembolic events, such as pulmonary embolism, deep vein thrombosis, or arterial thrombosis. People with COVID-19 who develop thromboembolism have a worse prognosis. Anticoagulants such as heparinoids (heparins or pentasaccharides), vitamin K antagonists and direct anticoagulants are used for the prevention and treatment of venous or arterial thromboembolism. Besides their anticoagulant properties, heparinoids have an additional anti-inflammatory potential. However, the benefit of anticoagulants for people with COVID-19 is still under debate.

OBJECTIVES

To assess the benefits and harms of anticoagulants versus active comparator, placebo or no intervention in people hospitalised with COVID-19.

SEARCH METHODS

We searched the CENTRAL, MEDLINE, Embase, LILACS and IBECS databases, the Cochrane COVID-19 Study Register and medRxiv preprint database from their inception to 14 April 2021. We also checked the reference lists of any relevant systematic reviews identified, and contacted specialists in the field for additional references to trials.

SELECTION CRITERIA

Eligible studies were randomised controlled trials (RCTs), quasi-RCTs, cluster-RCTs and cohort studies that compared prophylactic anticoagulants versus active comparator, placebo or no intervention for the management of people hospitalised with COVID-19. We excluded studies without a comparator group and with a retrospective design (all previously included studies) as we were able to include better study designs. Primary outcomes were all-cause mortality and necessity for additional respiratory support. Secondary outcomes were mortality related to COVID-19, deep vein thrombosis, pulmonary embolism, major bleeding, adverse events, length of hospital stay and quality of life.

DATA COLLECTION AND ANALYSIS

We used standard Cochrane methodological procedures. We used Cochrane RoB 1 to assess the risk of bias for RCTs, ROBINS-I to assess risk of bias for non-randomised studies (NRS) and GRADE to assess the certainty of evidence. We meta-analysed data when appropriate.

MAIN RESULTS

We included seven studies (16,185 participants) with participants hospitalised with COVID-19, in either intensive care units, hospital wards or emergency departments. Studies were from Brazil (2), Iran (1), Italy (1), and the USA (1), and two involved more than country. The mean age of participants was 55 to 68 years and the follow-up period ranged from 15 to 90 days. The studies assessed the effects of heparinoids, direct anticoagulants or vitamin K antagonists, and reported sparse data or did not report some of our outcomes of interest: necessity for additional respiratory support, mortality related to COVID-19, and quality of life. Higher-dose versus lower-dose anticoagulants (4 RCTs, 4647 participants) Higher-dose anticoagulants result in little or no difference in all-cause mortality (risk ratio (RR) 1.03, 95% CI 0.92 to 1.16, 4489 participants; 4 RCTs) and increase minor bleeding (RR 3.28, 95% CI 1.75 to 6.14, 1196 participants; 3 RCTs) compared to lower-dose anticoagulants up to 30 days (high-certainty evidence). Higher-dose anticoagulants probably reduce pulmonary embolism (RR 0.46, 95% CI 0.31 to 0.70, 4360 participants; 4 RCTs), and slightly increase major bleeding (RR 1.78, 95% CI 1.13 to 2.80, 4400 participants; 4 RCTs) compared to lower-dose anticoagulants up to 30 days (moderate-certainty evidence). Higher-dose anticoagulants may result in little or no difference in deep vein thrombosis (RR 1.08, 95% CI 0.57 to 2.03, 3422 participants; 4 RCTs), stroke (RR 0.91, 95% CI 0.40 to 2.03, 4349 participants; 3 RCTs), major adverse limb events (RR 0.33, 95% CI 0.01 to 7.99, 1176 participants; 2 RCTs), myocardial infarction (RR 0.86, 95% CI 0.48 to 1.55, 4349 participants; 3 RCTs), atrial fibrillation (RR 0.35, 95% CI 0.07 to 1.70, 562 participants; 1 study), or thrombocytopenia (RR 0.94, 95% CI 0.71 to 1.24, 2789 participants; 2 RCTs) compared to lower-dose anticoagulants up to 30 days (low-certainty evidence). It is unclear whether higher-dose anticoagulants have any effect on necessity for additional respiratory support, mortality related to COVID-19, and quality of life (very low-certainty evidence or no data). Anticoagulants versus no treatment (3 prospective NRS, 11,538 participants) Anticoagulants may reduce all-cause mortality but the evidence is very uncertain due to two study results being at critical and serious risk of bias (RR 0.64, 95% CI 0.55 to 0.74, 8395 participants; 3 NRS; very low-certainty evidence). It is uncertain if anticoagulants have any effect on necessity for additional respiratory support, mortality related to COVID-19, deep vein thrombosis, pulmonary embolism, major bleeding, stroke, myocardial infarction and quality of life (very low-certainty evidence or no data). Ongoing studies We found 62 ongoing studies in hospital settings (60 RCTs, 35,470 participants; 2 prospective NRS, 120 participants) in 20 different countries. Thirty-five ongoing studies plan to report mortality and 26 plan to report necessity for additional respiratory support. We expect 58 studies to be completed in December 2021, and four in July 2022. From 60 RCTs, 28 are comparing different doses of anticoagulants, 24 are comparing anticoagulants versus no anticoagulants, seven are comparing different types of anticoagulants, and one did not report detail of the comparator group.

AUTHORS' CONCLUSIONS

When compared to a lower-dose regimen, higher-dose anticoagulants result in little to no difference in all-cause mortality and increase minor bleeding in people hospitalised with COVID-19 up to 30 days. Higher-dose anticoagulants possibly reduce pulmonary embolism, slightly increase major bleeding, may result in little to no difference in hospitalisation time, and may result in little to no difference in deep vein thrombosis, stroke, major adverse limb events, myocardial infarction, atrial fibrillation, or thrombocytopenia.  Compared with no treatment, anticoagulants may reduce all-cause mortality but the evidence comes from non-randomised studies and is very uncertain. It is unclear whether anticoagulants have any effect on the remaining outcomes compared to no anticoagulants (very low-certainty evidence or no data). Although we are very confident that new RCTs will not change the effects of different doses of anticoagulants on mortality and minor bleeding, high-quality RCTs are still needed, mainly for the other primary outcome (necessity for additional respiratory support), the comparison with no anticoagulation, when comparing the types of anticoagulants and giving anticoagulants for a prolonged period of time.

The association of hemoglobin drop with in-hospital outcomes in COVID-19 patients

BACKGROUND

Bleeding events can be critical in hospitalized patients with COVID-19, especially those with aggressive anticoagulation therapy.

AIM

We aimed to investigate whether hemoglobin drop was associated with increased risk of acute kidney injury (AKI) and in-hospital mortality among patients with COVID-19.

DESIGN

Retrospective cohort study.

METHODS

This retrospective study was conducted by review of the medical records of 6683 patients with laboratory-confirmed COVID-19 hospitalized in the Mount Sinai Health system between 1st March 2020 and 30th March 2021. We compared patients with and without hemoglobin drop >3 g/dl during hospitalization within a week after admissions, using inverse probability treatment weighted analysis (IPTW). Outcomes of interest were in-hospital mortality and AKI which was defined as serum creatine change of 0.3 mg/dl increase or 1.5 times baseline.

RESULTS

Of the 6683 patients admitted due to COVID-19, 750 (11.2%) patients presented with a marked hemoglobin drop. Patients with hemoglobin drop were more likely to receive therapeutic anticoagulation within 2 days after admissions. Patients with hemoglobin drop had higher crude in-hospital mortality (40.8% vs. 20.0%, P < 0.001) as well as AKI (51.4% vs. 23.9%, P < 0.001) compared to those without. IPTW analysis showed that hemoglobin drop was associated with higher in-hospital mortality compared to those without (odds ratio (OR) [95% confidential interval (CI)]: 2.21 [1.54-2.88], P < 0.001) as well as AKI (OR [95% CI]: 2.79 [2.08-3.73], P < 0.001).

CONCLUSIONS

Hemoglobin drop during COVID-19 related hospitalizations was associated with a higher risk of AKI and in-hospital mortality.

Arterial and Venous Thrombosis Complicated in COVID-19: A Retrospective Single Center Analysis in Japan

Background: Thrombosis is a characteristic complication in coronavirus disease 2019 (COVID-19). Since coagulopathy has been observed over the entire clinical course, thrombosis might be a clue to understanding the specific pathology in COVID-19. Currently, there is limited epidemiological data of COVID-19-associated thrombosis in the Japanese population and none regarding variant strains of SARS-CoV-2. Here, we elucidate the risk factors and the pattern of thrombosis in COVID-19 patients. Methods: The patients consecutively admitted to Tokyo Medical and Dental University Hospital with COVID-19 were retrospectively analyzed. SARS-CoV-2 variants of concern/interest (VOC/VOI) carrying the spike protein mutants E484K, N501Y, or L452R were identified by PCR-based analysis. All thrombotic events were diagnosed by clinical symptoms, ultrasonography, and/or radiological tests. Results: Among the 516 patients, 32 patients experienced 42 thromboembolic events. Advanced age, severe respiratory conditions, and several abnormal laboratory markers were associated with the development of thrombosis. While thrombotic events occurred in 13% of the patients with a severe respiratory condition, those events still occurred in 2.5% of the patients who did not require oxygen therapy. Elevated D-dimer and ferritin levels on admission were independent risk factors of thrombosis (adjusted odds ratio 9.39 and 3.11, 95% confidence interval 2.08-42.3, and 1.06-9.17, respectively). Of the thrombotic events, 22 were venous, whereas 20 were arterial. While patients with thrombosis received anticoagulation and antiinflammatory therapies with a higher proportion, the mortality rate, organ dysfunctions, and bleeding complications in these patients were higher than those without thrombosis. The incidence of thrombosis in COVID-19 became less frequent over time, such as during the replacement of the earlier strains of SARS-CoV-2 by VOC/VOI and during increased use of anticoagulatory therapeutics. Conclusion: This study elucidated that elevated D-dimer and ferritin levels are useful biomarkers of thrombosis in COVID-19 patients. The comparable incidence of arterial thrombosis with venous thrombosis and the development of thrombosis in less severe patients required further considerations for the management of Japanese patients with COVID-19. Further studies would be required to identify high-risk populations and establish appropriate interventions for thrombotic complications in COVID-19.

SARS-CoV-2, Cardiovascular Diseases, and Noncoding RNAs: A Connected Triad

Coronavirus Disease 2019 (COVID-19), caused by the Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2), is characterized by important respiratory impairments frequently associated with severe cardiovascular damages. Moreover, patients with pre-existing comorbidity for cardiovascular diseases (CVD) often present a dramatic increase in inflammatory cytokines release, which increases the severity and adverse outcomes of the infection and, finally, mortality risk. Despite this evident association at the clinical level, the mechanisms linking CVD and COVID-19 are still blurry and unresolved. Noncoding RNAs (ncRNAs) are functional RNA molecules transcribed from DNA but usually not translated into proteins. They play an important role in the regulation of gene expression, either in relatively stable conditions or as a response to different stimuli, including viral infection, and are therefore considered a possible important target in the design of specific drugs. In this review, we introduce known associations and interactions between COVID-19 and CVD, discussing the role of ncRNAs within SARS-CoV-2 infection from the perspective of the development of efficient pharmacological tools to treat COVID-19 patients and taking into account the equally dramatic associated consequences, such as those affecting the cardiovascular system.

Efficacy and safety of direct-acting oral anticoagulants compared to vitamin K antagonists in COVID-19 outpatients with cardiometabolic diseases

BACKGROUND

It remains uncertain if prior use of oral anticoagulants (OACs) in COVID-19 outpatients with multimorbidity impacts prognosis, especially if cardiometabolic diseases are present. Clinical outcomes 30-days after COVID-19 diagnosis were compared between outpatients with cardiometabolic disease receiving vitamin K antagonist (VKA) or direct-acting OAC (DOAC) therapy at time of COVID-19 diagnosis.

METHODS

A study was conducted using TriNetX, a global federated health research network. Adult outpatients with cardiometabolic disease (i.e. diabetes mellitus and any disease of the circulatory system) treated with VKAs or DOACs at time of COVID-19 diagnosis between 20-Jan-2020 and 15-Feb-2021 were included. Propensity score matching (PSM) was used to balance cohorts receiving VKAs and DOACs. The primary outcomes were all-cause mortality, intensive care unit (ICU) admission/mechanical ventilation (MV) necessity, intracranial haemorrhage (ICH)/gastrointestinal bleeding, and the composite of any arterial or venous thrombotic event(s) at 30-days after COVID-19 diagnosis.

RESULTS

2275 patients were included. After PSM, 1270 patients remained in the study (635 on VKAs; 635 on DOACs). VKA-treated patients had similar risks and 30-day event-free survival than patients on DOACs regarding all-cause mortality, ICU admission/MV necessity, and ICH/gastrointestinal bleeding. The risk of any arterial or venous thrombotic event was 43% higher in the VKA cohort (hazard ratio 1.43, 95% confidence interval 1.03-1.98; Log-Rank test p = 0.029).

CONCLUSION

In COVID-19 outpatients with cardiometabolic diseases, prior use of DOAC therapy compared to VKA therapy at the time of COVID-19 diagnosis demonstrated lower risk of arterial or venous thrombotic outcomes, without increasing the risk of bleeding.

Therapeutic versus prophylactic anticoagulation for patients admitted to hospital with COVID-19 and elevated D-dimer concentration (ACTION): an open-label, multicentre, randomised, controlled trial

BACKGROUND

COVID-19 is associated with a prothrombotic state leading to adverse clinical outcomes. Whether therapeutic anticoagulation improves outcomes in patients hospitalised with COVID-19 is unknown. We aimed to compare the efficacy and safety of therapeutic versus prophylactic anticoagulation in this population.

METHODS

We did a pragmatic, open-label (with blinded adjudication), multicentre, randomised, controlled trial, at 31 sites in Brazil. Patients (aged ≥18 years) hospitalised with COVID-19 and elevated D-dimer concentration, and who had COVID-19 symptoms for up to 14 days before randomisation, were randomly assigned (1:1) to receive either therapeutic or prophylactic anticoagulation. Therapeutic anticoagulation was in-hospital oral rivaroxaban (20 mg or 15 mg daily) for stable patients, or initial subcutaneous enoxaparin (1 mg/kg twice per day) or intravenous unfractionated heparin (to achieve a 0·3-0·7 IU/mL anti-Xa concentration) for clinically unstable patients, followed by rivaroxaban to day 30. Prophylactic anticoagulation was standard in-hospital enoxaparin or unfractionated heparin. The primary efficacy outcome was a hierarchical analysis of time to death, duration of hospitalisation, or duration of supplemental oxygen to day 30, analysed with the win ratio method (a ratio >1 reflects a better outcome in the therapeutic anticoagulation group) in the intention-to-treat population. The primary safety outcome was major or clinically relevant non-major bleeding through 30 days. This study is registered with ClinicalTrials.gov (NCT04394377) and is completed.

FINDINGS

From June 24, 2020, to Feb 26, 2021, 3331 patients were screened and 615 were randomly allocated (311 [50%] to the therapeutic anticoagulation group and 304 [50%] to the prophylactic anticoagulation group). 576 (94%) were clinically stable and 39 (6%) clinically unstable. One patient, in the therapeutic group, was lost to follow-up because of withdrawal of consent and was not included in the primary analysis. The primary efficacy outcome was not different between patients assigned therapeutic or prophylactic anticoagulation, with 28 899 (34·8%) wins in the therapeutic group and 34 288 (41·3%) in the prophylactic group (win ratio 0·86 [95% CI 0·59-1·22], p=0·40). Consistent results were seen in clinically stable and clinically unstable patients. The primary safety outcome of major or clinically relevant non-major bleeding occurred in 26 (8%) patients assigned therapeutic anticoagulation and seven (2%) assigned prophylactic anticoagulation (relative risk 3·64 [95% CI 1·61-8·27], p=0·0010). Allergic reaction to the study medication occurred in two (1%) patients in the therapeutic anticoagulation group and three (1%) in the prophylactic anticoagulation group.

INTERPRETATION

In patients hospitalised with COVID-19 and elevated D-dimer concentration, in-hospital therapeutic anticoagulation with rivaroxaban or enoxaparin followed by rivaroxaban to day 30 did not improve clinical outcomes and increased bleeding compared with prophylactic anticoagulation. Therefore, use of therapeutic-dose rivaroxaban, and other direct oral anticoagulants, should be avoided in these patients in the absence of an evidence-based indication for oral anticoagulation.

FUNDING

Coalition COVID-19 Brazil, Bayer SA.

Thromboembolic Complications of SARS-CoV-2 and Metabolic Derangements: Suggestions from Clinical Practice Evidence to Causative Agents

Severe Acute Respiratory Syndrome (SARS) Coronavirus (CoV)-2 is a recently identified positive sense single-strand RNA (ssRNA) β-coronavirus. The viral spike proteins infect human hosts by binding to the cellular receptor angiotensin-converting enzyme 2 (ACE2). The infection causes a systemic illness involving cell metabolism. This widespread involvement is implicated in the pathophysiology of the illness which ranges from mild to severe, requiring multi organ support, ranging from oxygen supplementation to full cardiovascular and respiratory support. Patients with multiple co-existing comorbidities are also at a higher risk. The aim of this review is to explore the exact mechanisms by which COVID-19 affects patients systemically with a primary focus on the bleeding and thrombotic complications linked with the disease. Issues surrounding the thrombotic complications following administration of the ChAdOx1 nCoV-19 (Astra-Zeneca-Oxford) vaccine have also been illustrated. Risk stratification and treatment options in these patients should be tailored according to clinical severity with input from a multidisciplinary team.

Prophylactic anticoagulants for people hospitalised with COVID-19

BACKGROUND

Coronavirus disease 2019 (COVID-19) is a serious disease caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The primary manifestation is respiratory insufficiency that can also be related to diffuse pulmonary microthrombosis in people with COVID-19. This disease also causes thromboembolic events, such as pulmonary embolism, deep venous thrombosis, arterial thrombosis, catheter thrombosis, and disseminated intravascular coagulopathy. Recent studies have indicated a worse prognosis for people with COVID-19 who developed thromboembolism. Anticoagulants are medications used in the prevention and treatment of venous or arterial thromboembolic events. Several drugs are used in the prophylaxis and treatment of thromboembolic events, such as heparinoids (heparins or pentasaccharides), vitamin K antagonists and direct anticoagulants. Besides their anticoagulant properties, heparinoids have an additional anti-inflammatory potential, that may affect the clinical evolution of people with COVID-19. Some practical guidelines address the use of anticoagulants for thromboprophylaxis in people with COVID-19, however, the benefit of anticoagulants for people with COVID-19 is still under debate.

OBJECTIVES

To assess the effects of prophylactic anticoagulants versus active comparator, placebo or no intervention, on mortality and the need for respiratory support in people hospitalised with COVID-19.

SEARCH METHODS

We searched CENTRAL, MEDLINE, Embase, LILACS and IBECS databases, the Cochrane COVID-19 Study Register and medRxiv preprint database from their inception to 20 June 2020. We also checked reference lists of any relevant systematic reviews identified and contacted specialists in the field for additional references to trials.

SELECTION CRITERIA

Randomised controlled trials (RCTs), quasi-RCTs, cluster-RCTs and cohort studies that compared prophylactic anticoagulants (heparin, vitamin K antagonists, direct anticoagulants, and pentasaccharides) versus active comparator, placebo or no intervention for the management of people hospitalised with COVID-19. We excluded studies without a comparator group. Primary outcomes were all-cause mortality and need for additional respiratory support. Secondary outcomes were mortality related to COVID-19, deep vein thrombosis (DVT), pulmonary embolism, major bleeding, adverse events, length of hospital stay and quality of life.

DATA COLLECTION AND ANALYSIS

We used standard Cochrane methodological procedures. We used ROBINS-I to assess risk of bias for non-randomised studies (NRS) and GRADE to assess the certainty of evidence. We reported results narratively.

MAIN RESULTS

We identified no RCTs or quasi-RCTs that met the inclusion criteria. We included seven retrospective NRS (5929 participants), three of which were available as preprints. Studies were conducted in China, Italy, Spain and the USA. All of the studies included people hospitalised with COVID-19, in either intensive care units, hospital wards or emergency departments. The mean age of participants (reported in 6 studies) ranged from 59 to 72 years. Only three included studies reported the follow-up period, which varied from 8 to 35 days. The studies did not report on most of our outcomes of interest: need for additional respiratory support, mortality related to COVID-19, DVT, pulmonary embolism, adverse events, and quality of life. Anticoagulants (all types) versus no treatment (6 retrospective NRS, 5685 participants) One study reported a reduction in all-cause mortality (adjusted odds ratio (OR) 0.42, 95% confidence interval (CI) 0.26 to 0.66; 2075 participants). One study reported a reduction in mortality only in a subgroup of 395 people who required mechanical ventilation (hazard ratio (HR) 0.86, 95% CI 0.82 to 0.89). Three studies reported no differences in mortality (adjusted OR 1.64, 95% CI 0.92 to 2.92; 449 participants; unadjusted OR 1.66, 95% CI 0.76 to 3.64; 154 participants and adjusted risk ratio (RR) 1.15, 95% CI 0.29 to 2.57; 192 participants). One study reported zero events in both intervention groups (42 participants). The overall risk of bias for all-cause mortality was critical and the certainty of the evidence was very low. One NRS reported bleeding events in 3% of the intervention group and 1.9% of the control group (OR 1.62, 95% CI 0.96 to 2.71; 2773 participants; low-certainty evidence). Therapeutic-dose anticoagulants versus prophylactic-dose anticoagulants (1 retrospective NRS, 244 participants) The study reported a reduction in all-cause mortality (adjusted HR 0.21, 95% CI 0.10 to 0.46) and a lower absolute rate of death in the therapeutic group (34.2% versus 53%). The overall risk of bias for all-cause mortality was serious and the certainty of the evidence was low. The study also reported bleeding events in 31.7% of the intervention group and 20.5% of the control group (OR 1.8, 95% CI 0.96 to 3.37; low-certainty evidence). Ongoing studies We found 22 ongoing studies in hospital settings (20 RCTs, 14,730 participants; 2 NRS, 997 participants) in 10 different countries (Australia (1), Brazil (1), Canada (2), China (3), France (2), Germany (1), Italy (4), Switzerland (1), UK (1) and USA (6)). Twelve ongoing studies plan to report mortality and six plan to report additional respiratory support. Thirteen studies are expected to be completed in December 2020 (6959 participants), eight in July 2021 (8512 participants), and one in December 2021 (256 participants). Four of the studies plan to include 1000 participants or more.

AUTHORS' CONCLUSIONS

There is currently insufficient evidence to determine the risks and benefits of prophylactic anticoagulants for people hospitalised with COVID-19. Since there are 22 ongoing studies that plan to evaluate more than 15,000 participants in this setting, we will add more robust evidence to this review in future updates.