Efficacy and Safety of Low Molecular Weight Heparin Versus Unfractionated Heparin for Prevention of Venous Thromboembolism in Trauma Patients: A Systematic Review and Meta-analysis

PURPOSE

Trauma patients are at high risk of VTE. We summarize the efficacy and safety of LMWH versus UFH for the prevention of VTE in trauma patients.

METHODS

We searched 6 databases from inception through March 12, 2021. We included randomized controlled trials (RCTs) or observational studies comparing LMWH versus UFH for thromboprophylaxis in adult trauma patients. We pooled effect estimates across RCTs and observational studies separately, using random-effects model and inverse variance weighting. We assessed risk of bias using the Cochrane tool for RCTs and the Risk of Bias in Non-Randomized Studies (ROBINS)-I tool for observational studies and assessed certainty of findings using Grading of Recommendations, Assessment, Development and Evaluations methodology.

RESULTS

We included 4 RCTs (879 patients) and 8 observational studies (306,747 patients). Based on pooled RCT data, compared to UFH, LMWH reduces deep vein thrombosis (RR 0.67, 95% CI 0.50 to 0.88, moderate certainty) and VTE (RR 0.68, 95% CI 0.51 to 0.90, moderate certainty). As compared to UFH, LMWH may reduce pulmonary embolism [adjusted odds ratio from pooled observational studies 0.56 (95% CI 0.50 to 0.62)] and mortality (adjusted odds ratio from pooled observational studies 0.54, 95% CI 0.45 to 0.65), though based on low certainty evidence. There was an uncertain effect on adverse events (RR from pooled RCTs 0.80, 95% CI 0.48 to 1.33, very low certainty) and heparin induced thrombocytopenia [RR from pooled RCTs 0.26 (95% CI 0.03 to 2.38, very low certainty)].

CONCLUSIONS

Among adult trauma patients, LMWH is superior to UFH for deep vein thrombosis and VTE prevention and may additionally reduce pulmonary embolism and mortality. The impact on adverse events and heparin induced thrombocytopenia is uncertain.

A systematic review and meta-analysis of incidence, prognosis, and laboratory indicators of venous thromboembolism in hospitalized patients with coronavirus disease 2019

OBJECTIVE

We have summarized the incidence, anticoagulation panels, laboratory characteristics, and mortality of venous thromboembolism (VTE) in hospitalized patients with coronavirus disease 2019 (COVID-19).

METHODS

After systematically searching PubMed, Embase, the Cochrane Library, MedRxiv, and BioRxiv, a systematic review and meta-analysis of 18 retrospective, 6 prospective observational, and 2 cross-sectional studies was performed according to the guidelines of the PRISMA (preferred reporting items for systematic reviews and meta-analyses) statement.

RESULTS

Overall, 4382 hospitalized patients with COVID-19 were included. Men accounted for significantly more patients than did women (odds ratio [OR], 1.59; 95% confidence interval [CI], 1.25-2.02; P < .001). The total incidence of VTE among the patients with COVID-19 was 28.3% (95% CI, 21.6%-35.4%), with an incidence of 38.0% (95% CI, 29.1%-47.4%) and 17.2% (95% CI, 11.4%-23.8%) among those with severe and general COVID-19, respectively. The total incidence of deep vein thrombosis (DVT) of the lower extremities was 18.3% (95% CI, 10.8%-27.2%). The incidence of DVT was 22.1% (95% CI, 11.0%-35.5%) and 12.8% (95% CI, 5.0%-23.3%) in those with severe and general COVID-19, respectively. The total incidence of pulmonary embolism was 17.6% (95% CI, 12.3%-23.5%), with a rate of 21.7% (95% CI, 14.8%-29.3%) in severe cases and 12.5% (95% CI, 6.1%-23.5%) in general cases. When COVID-19 severity was unclassified, the mortality for the patients with VTE was not significantly greater (25.2%; 95% CI, 12.2%-40.5%) than that for those without VTE (10.2%; 95% CI, 3.4%-19.5%; OR, 1.88; 95% CI, 0.46-7.64; P = .377). However, among the patients with severe COVID-19, those who had developed VTE had significantly greater mortality compared with those without VTE (OR, 2.02; 95% CI, 1.15-3.53; P = .014). The patients with COVID-19 and VTE had significantly higher D-dimer levels than did similar patients without VTE in multiple studies.

CONCLUSIONS

The occurrence of VTE, DVT, and pulmonary embolism has been substantial among hospitalized patients with COVID-19, especially among those with severe COVID-19. Patients with severe COVID-19 and VTE had significantly greater mortality compared with similar patients without VTE. An increased D-dimer level might be an indicator of the occurrence of VTE in patients with COVID-19.

Thromboprophylaxis strategies to improve the prognosis of COVID-19

The outbreak of 2019 novel coronavirus disease (Covid-19) has deeply challenged the world population, but also our medical knowledge. Special attention has been paid early to an activation of coagulation, then to an elevated rate of venous thromboembolism (VTE) in patients hospitalized with severe COVID-19. These data suggested that anticoagulant drugs should be evaluated in the treatment of patients with COVID-19. The publication of unexpected high rates of VTE in patients hospitalized with COVID-19, despite receiving thromboprophylaxis, open the way to dedicated trials, evaluating modified regimens of thromboprophylaxis. Moreover, the further improvement in our comprehension of the disease, particularly the pulmonary endothelial dysfunction increased the hope that anticoagulant drugs may also protect patients from pulmonary thrombosis. In this comprehensive review, we cover the different situations where thromboprophylaxis standard may be modified (medically-ill inpatients, ICU inpatients, outpatients), and describe some of the current randomized controls trials evaluating new regimens of thromboprophylaxis in patients with COVID-19, including the preliminary available results. We also discuss the potential of anticoagulant drugs to target the thromboinflammation described in patients with severe COVID-19.

Pulmonary Embolism Response Team utilization during the COVID-19 pandemic

Coronavirus disease 2019 (COVID-19) may predispose patients to venous thromboembolism (VTE). Limited data are available on the utilization of the Pulmonary Embolism Response Team (PERT) in the setting of the COVID-19 global pandemic. We performed a single-center study to evaluate treatment, mortality, and bleeding outcomes in patients who received PERT consultations in March and April 2020, compared to historical controls from the same period in 2019. Clinical data were abstracted from the electronic medical record. The primary study endpoints were inpatient mortality and GUSTO moderate-to-severe bleeding. The frequency of PERT utilization was nearly threefold higher during March and April 2020 (n = 74) compared to the same period in 2019 (n = 26). During the COVID-19 pandemic, there was significantly less PERT-guided invasive treatment (5.5% vs 23.1%, p = 0.02) with a numerical but not statistically significant trend toward an increase in the use of systemic fibrinolytic therapy (13.5% vs 3.9%, p = 0.3). There were nonsignificant trends toward higher in-hospital mortality or moderate-to-severe bleeding in patients receiving PERT consultations during the COVID-19 period compared to historical controls (mortality 14.9% vs 3.9%, p = 0.18 and moderate-to-severe bleeding 35.1% vs 19.2%, p = 0.13). In conclusion, PERT utilization was nearly threefold higher during the COVID-19 pandemic than during the historical control period. Among patients evaluated by PERT, in-hospital mortality or moderate-to-severe bleeding were not significantly different, despite being numerically higher, while invasive therapy was utilized less frequently during the COVID-19 pandemic.

Venous thromboembolism in COVID-19: A systematic review and meta-analysis

Severe coronavirus disease 2019 (COVID-19) is associated with increased risk of venous thromboembolism events (VTE). This study performed a systematic review in PubMed/EMBASE of studies reporting the prevalence of VTE in patients with COVID-19 who were totally screened/assessed for deep vein thrombosis (DVT) and/or for pulmonary embolism (PE). Among 47 candidate studies (n = 6459; 33 in Europe), 17 studies (n = 3973; weighted age 63.0 years, males 60%, intensive care unit (ICU) 16%) reported the prevalence of PE with a pooled estimate of 32% (95% CI: 25, 40%), and 32 studies (n = 2552; weighted age 62.6 years, males 57%, ICU 49%) reported the prevalence of DVT with a pooled estimate of 27% (95% CI: 21, 34%). A total of 36 studies reported the use of at least prophylactic antithrombotic treatment in the majority of their patients. Meta-regression analysis showed that the prevalence of VTE was higher across studies with a higher percentage of ICU patients and higher study population mean D-dimer values, and lower in studies with mixed dosing of anticoagulation in ⩾ 50% of the population compared to studies with standard prophylactic dosing of anticoagulation in < 50% of the population. The pooled odds ratio for death in patients with COVID-19 and VTE versus those without VTE (17 studies, n = 2882) was 2.1 (95% CI: 1.2, 3.6). Hospitalized patients with severe COVID-19 are at high VTE risk despite prophylactic anticoagulation. Further research should investigate the individualized VTE risk of patients with COVID-19 and the optimal preventive antithrombotic therapy. PROSPERO Registration No.: CRD42020185543.

Rationale and design for the study of rivaroxaban to reduce thrombotic events, hospitalization and death in outpatients with COVID-19: The PREVENT-HD study

BACKGROUND

COVID-19 is associated with both venous and arterial thrombotic complications. While prophylactic anticoagulation is now widely recommended for hospitalized patients with COVID-19, the effectiveness and safety of thromboprophylaxis in outpatients with COVID-19 has not been established.

STUDY DESIGN

PREVENT-HD is a double-blind, placebo-controlled, pragmatic, event-driven phase 3 trial to evaluate the efficacy and safety of rivaroxaban in symptomatic outpatients with laboratory-confirmed COVID-19 at risk for thrombotic events, hospitalization, and death. Several challenges posed by the pandemic have necessitated innovative approaches to clinical trial design, start-up, and conduct. Participants are randomized in a 1:1 ratio, stratified by time from COVID-19 confirmation, to either rivaroxaban 10 mg once daily or placebo for 35 days. The primary efficacy end point is a composite of symptomatic venous thromboembolism, myocardial infarction, ischemic stroke, acute limb ischemia, non-central nervous system systemic embolization, all-cause hospitalization, and all-cause mortality. The primary safety end point is fatal and critical site bleeding according to the International Society on Thrombosis and Haemostasis definition. Enrollment began in August 2020 and is expected to enroll approximately 4,000 participants to yield the required number of end point events.

CONCLUSIONS

PREVENT-HD is a pragmatic trial evaluating the efficacy and safety of the direct oral anticoagulant rivaroxaban in the outpatient setting to reduce major venous and arterial thrombotic events, hospitalization, and mortality associated with COVID-19.

Thrombosis, Bleeding, and the Observational Effect of Early Therapeutic Anticoagulation on Survival in Critically Ill Patients With COVID-19

BACKGROUND

Hypercoagulability may be a key mechanism of death in patients with coronavirus disease 2019 (COVID-19).

OBJECTIVE

To evaluate the incidence of venous thromboembolism (VTE) and major bleeding in critically ill patients with COVID-19 and examine the observational effect of early therapeutic anticoagulation on survival.

DESIGN

In a multicenter cohort study of 3239 critically ill adults with COVID-19, the incidence of VTE and major bleeding within 14 days after intensive care unit (ICU) admission was evaluated. A target trial emulation in which patients were categorized according to receipt or no receipt of therapeutic anticoagulation in the first 2 days of ICU admission was done to examine the observational effect of early therapeutic anticoagulation on survival. A Cox model with inverse probability weighting to adjust for confounding was used.

SETTING

67 hospitals in the United States.

PARTICIPANTS

Adults with COVID-19 admitted to a participating ICU.

MEASUREMENTS

Time to death, censored at hospital discharge, or date of last follow-up.

RESULTS

Among the 3239 patients included, the median age was 61 years (interquartile range, 53 to 71 years), and 2088 (64.5%) were men. A total of 204 patients (6.3%) developed VTE, and 90 patients (2.8%) developed a major bleeding event. Independent predictors of VTE were male sex and higher D-dimer level on ICU admission. Among the 2809 patients included in the target trial emulation, 384 (11.9%) received early therapeutic anticoagulation. In the primary analysis, during a median follow-up of 27 days, patients who received early therapeutic anticoagulation had a similar risk for death as those who did not (hazard ratio, 1.12 [95% CI, 0.92 to 1.35]).

LIMITATION

Observational design.

CONCLUSION

Among critically ill adults with COVID-19, early therapeutic anticoagulation did not affect survival in the target trial emulation.

PRIMARY FUNDING SOURCE

None.

Outcomes of COVID-19 Complications and their Possibilities as Potential Triggers of Stroke

Introduction

There is limited literature on coronavirus disease 2019 (COVID -19) complications such as thromboembolism, cardiac complications etc. as possible trigger for stroke. Hence, we aim to evaluate the prevalence and outcomes of COVID-19 related cardiovascular complications and secondary infection and their possibility as potential triggers for the stroke.

Methods

Data from observational studies describing the complications [acute cardiac injury (ACI), cardiac arrhythmias (CA), disseminated intravascular coagulation (DIC), septic shock, secondary infection] and outcomes of COVID‐19 hospitalized patients from December 1, 2019 to June 30, 2020, were extracted following PRISMA guidelines. Adverse outcomes defined as intensive care units, oxygen saturation less than 90%, invasive mechanical ventilation, severe disease, and in‐hospital mortality. The odds ratio and 95% confidence interval were obtained, and forest plots were created using random‐effects models. A short review of these complications as triggers of stroke was conducted.

Results

16 studies with 3480 confirmed COVID-19 patients, prevalence of ACI [38%vs5.9%], CA [26%vs5.3%], DIC [4%vs0.74%], septic shock [18%vs0.36%], and infection [30%vs12.5%] was higher among patients with poor outcomes. In meta-analysis, ACI [aOR:9.93(95%CI:3.95–25.00], CA [7.52(3.29–17.18)], DIC [7.36(1.24–43.73)], septic shock [30.12(7.56–120.10)], and infection [10.41(4.47–24.27)] had higher odds of adverse outcomes. Patients hospitalized with acute ischemic stroke and intracerebral hemorrhage, had complications like pulmonary embolism, venous thromboembolism, DIC, etc. and had poor outcomes

Conclusion

The complications like acute cardiac injury, cardiac arrhythmias, DIC, septic shock, and secondary infection had poor outcomes. Patients with stroke were having history of these complications. Long term monitoring is required in such patients to prevent stroke and mitigate adverse outcomes.

Inflammatory Biomarkers in the Short-Term Prognosis of Venous Thromboembolism: A Narrative Review

The relationship between inflammation and venous thrombosis is not well understood. An inflammatory response may be both the cause and consequence of venous thromboembolism (VTE). In fact, several risk factors of VTE modulate thrombosis through inflammatory markers. Acute pulmonary embolism (PE) is burdened by a remarkable mortality rate, up to 34% in severely ill patients presenting with hemodynamic instability. Initial mortality risk stratification is based on hemodynamic instability. Patients with a situation of hemodynamic stability require immediate further risk assessment based on clinical, imaging, and circulating biomarkers, as well as the presence of comorbidities. Some inflammatory biomarkers have shown potential usefulness in the risk stratification of patients with VTE, especially acute PE. C-reactive protein on admission is associated with 30-day mortality and bleeding in VTE patients. P-selectin is associated with right ventricle dysfunction in PE patients and might be associated with VTE recurrences and the extension of thrombosis. Tissue factor microparticles are associated with VTE recurrence in cancer-associated thrombosis. Other inflammatory biomarkers present scarce evidence (inflammatory cytokines, erythrocyte sedimentation rate, fibrinogen, leukocyte count). In this manuscript, we will review the prognostic role of different inflammatory biomarkers available both for clinical practice and research in VTE patients.

Understanding the andromeda strain - The role of cytokine release, coagulopathy and antithrombin III in SARS-CoV2 critical illness

As the current coronavirus pandemic continues and cases of COVID-19 critical illness rise, physicians and scientists across the globe are working to understand and study its pathophysiology. Part of the pathology of this illness may result from its prothrombotic potential as witnessed from derangements in coagulation and thrombotic complications reported in observational studies performed in China and Europe to findings of microthrombosis upon autopsy analysis of patients who succumbed to COVID-19. Multiple organizations, including the American Society of Hematology (ASH), recommend the routine use of prophylactic heparin to temper the thrombotic complications of this illness given its mortality benefit in severe COVID-19 infections. Reductions in circulating levels of Antithrombin III (AT), the primary mediator of heparin's action, is present in cases of coronavirus related critical illness. AT's use as a prognostic marker, an important effector of heparin resistance, and a potential therapeutic target for COVID-19 remains to be explored.

Association of timing of initiation of pharmacologic venous thromboembolism prophylaxis with outcomes in trauma patients

BACKGROUND

Patients are at a high risk for developing venous thromboembolism (VTE) following traumatic injury. We examined the relationship between timing of initiation of pharmacologic prophylaxis with VTE complications.

METHODS

Trauma quality collaborative data from 34 American College of Surgeons Committee on Trauma-verified levels I and II trauma centers were analyzed. Patients were excluded if they were on anticoagulant therapy at the time of injury, had hospitalization <48 hours, or received no or nonstandard pharmacologic VTE prophylaxis (heparin drip). Patient comparison groups were based on timing of initiation of VTE prophylaxis relative to hospital presentation (0 to <24 hours, 24 to <48 hours, ≥48 hours). Risk-adjusted rates of VTE events were calculated accounting for patient factors including type of pharmacologic agent in addition to standard trauma patient confounders. A sensitivity analysis was performed excluding patients who received blood in the first 4 hours and/or patients with a significant traumatic brain injury.

RESULTS

Within the 79,386 patients analyzed, there were 1,495 (1.9%) who experienced a VTE complication and 1,437 (1.8%) who died. After adjusting for type of prophylaxis and patient factors, the risk of a VTE event was significantly increased in the 24- to <48-hour (odds ratio, 1.26; 95% confidence interval, 1.09-1.47; p = 0.002) and ≥48-hour (odds ratio, 2.35; 95% confidence interval, 2.04-2.70; p < 0.001) cohorts relative to patients initiated at 0 to <24 hours. These VTE event findings remained significant after exclusion of perceived higher-risk patients in a sensitivity analysis.

CONCLUSION

Early initiation of pharmacologic VTE prophylaxis in stable trauma patients is associated with lower rates of VTE.

LEVEL OF EVIDENCE

Diagnostic, level III.

Edoxaban for the Long-Term Therapy of Venous Thromboembolism: Should the Criteria for Dose Reduction be Revised?

Edoxaban is used for venous thromboembolism (VTE) treatment. Real-life data are lacking about its use in long-term therapy. We aimed to assess the efficacy and the safety of edoxaban for long-term VTE treatment in a real-life setting. Patients with VTE included in the Registro Informatizado Enfermedad TromboEmbólica (RIETE) registry, receiving edoxaban 60 or 30 mg daily were prospectively followed up to validate the benefit of using different dosages. The main outcome was the composite of VTE recurrences or major bleeding in patients with or without criteria for dose reduction. Multivariable analysis to identify predictors for the composite outcome was performed. From October 2015 to November 2019, 562 patients received edoxaban for long-term therapy. Most (94%) of the 416 patients not meeting criteria for dose reduction received 60 mg daily, and 92 patients meeting criteria (63%) received 30 mg daily. During treatment, two patients developed recurrent VTE, six had major bleeding and nine died (2 from fatal bleeding). Among patients not meeting criteria for dose reduction, those receiving 30 mg daily had a higher rate of the composite event (hazard ratio (HR) 8.37; 95% confidence interval (CI) 1.12-42.4) and a significant higher mortality rate (HR 31.1; 95% CI 4.63-262) than those receiving 60 mg. Among patients meeting criteria for dose reduction, those receiving 60 mg daily had no events, and a nonsignificantly higher mortality rate (HR 5.04; 95% CI 0.54-133) than those receiving 30 mg daily. In conclusion, edoxaban seems to be effective and safe for long-term VTE treatment in real life. Criteria for dose reduction should be reformulated.

Risk of Venous Thromboembolism in Acute Necrotizing Pancreatitis: A Large Database Study

OBJECTIVES

Studies on the incidence of venous thromboembolism (VTE) in acute pancreatitis (AP) are scarce. We conducted a large database study to evaluate this relationship.

METHODS

Data were extracted from a large electronic health record (Explorys; IBM Watson Health, Armonk, NY). We identified patients with AP in 2018 and 2019, analyzing VTE incidence at 30 days after diagnosis of AP. Univariate and multivariate analyses were performed to identify risk factors associated with VTE.

RESULTS

A total of 25,620 cases of acute necrotizing pancreatitis (ANP) and 155,800 cases of acute nonnecrotizing pancreatitis (ANNP) were identified. The incidence of VTE was 7.1% for ANP, compared with 2.8% in ANNP (P < 0.001). On multivariate analysis, ANP conferred significantly greater odds of VTE (adjusted odds ratio, 2.78; 95% confidence interval, 2.73-2.84; P < 0.001), independent of other variables. In those with ANP, the presence of VTE was associated with a significantly higher mortality (23.5% vs 15.9%, P < 0.001).

CONCLUSIONS

Acute necrotizing pancreatitis carries near 2.5-fold risk of VTE, and a 3-fold risk of PE, compared with those with ANNP. Venous thromboembolism development in ANP is associated with higher mortality.

Thrombolytic therapy in acute venous thromboembolism

Although anticoagulation remains the mainstay of treatment of acute venous thromboembolism (VTE), the use of thrombolytic agents or thrombectomy is required to immediately restore blood flow to thrombosed vessels. Nevertheless, systemic thrombolysis has not clearly been shown to improve outcomes in patients with large clot burdens in the lung or legs as compared with anticoagulation alone; this is in part due to the occurrence of intracranial hemorrhage in a small percentage of patients to whom therapeutic doses of a thrombolytic drug are administered. Algorithms have been developed to identify patients at high risk for poor outcomes resulting from large clot burdens and at low risk for major bleeding in an effort to improve outcomes in those receiving thrombolytic therapy. In acute pulmonary embolism (PE), hemodynamic instability is the key determinant of short-term survival and should prompt consideration of immediate thrombolysis. In hemodynamically stable PE, systemic thrombolysis is not recommended and should be used as rescue therapy if clinical deterioration occurs. Evidence is accumulating regarding the efficacy of administering reduced doses of thrombolytic agents systemically or via catheters directly into thrombi in an effort to lower bleed rates. In acute deep venous thrombosis, catheter-directed thrombolysis with thrombectomy can be used in severe or limb-threatening thrombosis but has not been shown to prevent postthrombotic syndrome. Because the management of acute VTE can be complex, having a rapid-response team (ie, PE response team) composed of physicians from different specialties may aid in the management of severely affected patients.

Which patients are at high risk of recurrent venous thromboembolism (deep vein thrombosis and pulmonary embolism)?

Recurrent venous thromboembolism (VTE, or deep vein thrombosis and pulmonary embolism) is associated with mortality and long-term morbidity. The circumstances in which an index VTE event occurred are crucial when personalized VTE recurrence risk is assessed. Patients who experience a VTE event in the setting of a transient major risk factor (such as surgery associated with general anesthesia for >30 minutes) are predicted to have a low VTE recurrence risk following discontinuation of anticoagulation, and limited-duration anticoagulation is generally recommended. In contrast, those patients whose VTE event occurred in the absence of risk factors or who have persistent risk factors have a higher VTE recurrence risk. Here, we review the literature surrounding VTE recurrence risk in a range of clinical conditions. We describe gender-specific risks, including VTE recurrence risk following hormone- and pregnancy-associated VTE events. Finally, we discuss how the competing impacts of VTE recurrence and bleeding have shaped international guideline recommendations.

Anticoagulant interventions in hospitalized patients with COVID-19: A scoping review of randomized controlled trials and call for international collaboration

INTRODUCTION

Coronavirus disease (COVID-19) is associated with a high incidence of thrombosis and mortality despite standard anticoagulant thromboprophylaxis. There is equipoise regarding the optimal dose of anticoagulant intervention in hospitalized patients with COVID-19 and consequently, immediate answers from high-quality randomized trials are needed.

METHODS

The World Health Organization's International Clinical Trials Registry Platform was searched on June 17, 2020 for randomized controlled trials comparing increased dose to standard dose anticoagulant interventions in hospitalized COVID-19 patients. Two authors independently screened the full records for eligibility and extracted data in duplicate.

RESULTS

A total of 20 trials were included in the review. All trials are open label, 5 trials use an adaptive design, 1 trial uses a factorial design, 2 trials combine multi-arm parallel group and factorial designs in flexible platform trials, and at least 15 trials have multiple study sites. With individual target sample sizes ranging from 30 to 3000 participants, the pooled sample size of all included trials is 12 568 participants. Two trials include only intensive care unit patients, and 10 trials base patient eligibility on elevated D-dimer levels. Therapeutic intensity anticoagulation is evaluated in 14 trials. All-cause mortality is part of the primary outcome in 14 trials.

DISCUSSION

Several trials evaluate different dose regimens of anticoagulant interventions in hospitalized patients with COVID-19. Because these trials compete for sites and study participants, a collaborative effort is needed to complete trials faster, conduct pooled analyses and bring effective interventions to patients more quickly.

COVID-19-Associated Coagulopathy and Inflammatory Response: What Do We Know Already and What Are the Knowledge Gaps?

Patients with coronavirus disease 2019 (COVID-19) frequently experience a coagulopathy associated with a high incidence of thrombotic events leading to poor outcomes. Here, biomarkers of coagulation (such as D-dimer, fibrinogen, platelet count), inflammation (such as interleukin-6), and immunity (such as lymphocyte count) as well as clinical scoring systems (such as sequential organ failure assessment [SOFA], International Society on Thrombosis and Hemostasis disseminated intravascular coagulation [ISTH DIC], and sepsis-induced coagulopathy [SIC] score) can be helpful in predicting clinical course, need for hospital resources (such as intensive care unit [ICU] beds, intubation and ventilator therapy, and extracorporeal membrane oxygenation [ECMO]) and patient's outcome in patients with COVID-19. However, therapeutic options are actually limited to unspecific supportive therapy. Whether viscoelastic testing can provide additional value in predicting clinical course, need for hospital resources and patient's outcome or in guiding anticoagulation in COVID-19-associated coagulopathy is still incompletely understood and currently under investigation (eg, in the rotational thromboelastometry analysis and standard coagulation tests in hospitalized patients with COVID-19 [ROHOCO] study). This article summarizes what we know already about COVID-19-associated coagulopathy and-perhaps even more importantly-characterizes important knowledge gaps.

Cancer associated thrombosis and mortality in patients with cancer stratified by khorana score risk levels

BACKGROUND

The Khorana score (KS) clinical algorithm is used to predict VTE risk in cancer patients. The study objective was to evaluate VTE and survival rates among patients newly diagnosed with cancer and stratified by KS in a real-world population.

METHODS

Data from the Optum® Clinformatics® DataMart database between 01/01/2012-09/30/2017 was used to identify adults with ≥ 1 hospitalization or ≥ 2 outpatient claims with a cancer diagnosis (index date). Only patients who were initiated on chemotherapy or radiation therapy were included. Patients were classified based on KS (KS = 0, 1, 2 or ≥ 3). Time-to-first VTE and survival were evaluated from the index date to the earliest among end of data availability or insurance coverage, death, or 12 months post-index using Kaplan-Meier (KM) analyses.

RESULTS

A total of 2,488 (KS = 0); 2,125 (KS = 1), 1,074 (KS = 2), and 507 (KS ≥ 3) cancer patients were included. The 12-month KM rates of VTE were 3.1%, 5.4%, 7.9%, and 14.9% (associated median time to VTE of 2.7, 3.0, 1.4, and 1.7 months) among KS = 0, 1, 2, and ≥ 3 cohorts, respectively. Corresponding adjusted hazard ratios (95% CIs) relative to the KS = 0 cohort were 1.72 (1.25-2.38), 2.46 (1.73-3.50), and 4.99 (3.40-7.31) for the KS = 1, 2, and ≥ 3 cohorts, respectively (all P < .001). Regardless of KS, patients with VTE had significantly lower survival rates than those without.

CONCLUSIONS

This real-world claims-based cohort study of newly diagnosed cancer patients showed significantly higher rates of VTE with increased KS, confirming its predictive ability. Moreover, VTE was associated with lower survival rates within each KS cohort.

Prophylaxis of thromboembolism during therapy with asparaginase in adults with acute lymphoblastic leukaemia

BACKGROUND

The risk of venous thromboembolism is increased in adults and enhanced by asparaginase-based chemotherapy, and venous thromboembolism introduces a secondary risk of treatment delay and premature discontinuation of key anti-leukaemic agents, potentially compromising survival. Yet, the trade-off between benefits and harms of primary thromboprophylaxis in adults with acute lymphoblastic leukaemia (ALL) treated according to asparaginase-based regimens is uncertain.  OBJECTIVES: The primary objectives were to assess the benefits and harms of primary thromboprophylaxis for first-time symptomatic venous thromboembolism in adults with ALL receiving asparaginase-based therapy compared with placebo or no thromboprophylaxis. The secondary objectives were to compare the benefits and harms of different groups of primary systemic thromboprophylaxis by stratifying the main results per type of drug (heparins, vitamin K antagonists, synthetic pentasaccharides, parenteral direct thrombin inhibitors, direct oral anticoagulants, and blood-derived products for antithrombin substitution).

SEARCH METHODS

We conducted a comprehensive literature search on 02 June 2020, with no language restrictions, including (1) electronic searches of Pubmed/MEDLINE; Embase/Ovid; Scopus/Elsevier; Web of Science Core Collection/Clarivate Analytics; and Cochrane Central Register of Controlled Trials (CENTRAL) and (2) handsearches of (i) reference lists of identified studies and related reviews; (ii) clinical trials registries (ClinicalTrials.gov registry; the International Standard Randomized Controlled Trial Number (ISRCTN) registry; the World Health Organisation's International Clinical Trials Registry Platform (ICTRP); and pharmaceutical manufacturers of asparaginase including Servier, Takeda, Jazz Pharmaceuticals, Ohara Pharmaceuticals, and Kyowa Pharmaceuticals), and (iii) conference proceedings (from the annual meetings of the American Society of Hematology (ASH); the European Haematology Association (EHA); the American Society of Clinical Oncology (ASCO); and the International Society on Thrombosis and Haemostasis (ISTH)). We conducted all searches from 1970 (the time of introduction of asparaginase in ALL treatment). We contacted the authors of relevant studies to identify any unpublished material, missing data, or information regarding ongoing studies.

SELECTION CRITERIA

Randomised controlled trials (RCTs); including quasi-randomised, controlled clinical, cross-over, and cluster-randomised trial designs) comparing any parenteral/oral preemptive anticoagulant or mechanical intervention with placebo or no thromboprophylaxis, or comparing two different pre-emptive anticoagulant interventions in adults aged at least 18 years with ALL treated according to asparaginase-based chemotherapy regimens. For the description of harms, non-randomised observational studies with a control group were eligible for inclusion.  DATA COLLECTION AND ANALYSIS: Using a standardised data collection form, two review authors independently screened and selected studies, extracted data, assessed risk of bias for each outcome using standardised tools (RoB 2.0 tool for RCTs and ROBINS-I tool for non-randomised studies) and the certainty of evidence for each outcome using the GRADE approach. Primary outcomes included first-time symptomatic venous thromboembolism, all-cause mortality, and major bleeding. Secondary outcomes included asymptomatic venous thromboembolism, venous thromboembolism-related mortality, adverse events (i.e. clinically relevant non-major bleeding and heparin-induced thrombocytopenia for trials using heparins), and quality of life. Analyses were performed according to the guidelines of the Cochrane Handbook for Systematic Reviews of Interventions. For non-randomised studies, we evaluated all studies (including studies judged to be at critical risk of bias in at least one of the ROBINS-I domains) in a sensitivity analysis exploring confounding.  MAIN RESULTS: We identified 23 non-randomised studies that met the inclusion criteria of this review, of which 10 studies provided no outcome data for adults with ALL. We included the remaining 13 studies in the 'Risk of bias' assessment, in which we identified invalid control group definition in two studies and judged outcomes of nine studies to be at critical risk of bias in at least one of the ROBINS-I domains and outcomes of two studies at serious risk of bias. We did not assess the benefits of thromboprophylaxis, as no RCTs were included. In the main descriptive analysis of harms, we included two retrospective non-randomised studies with outcomes judged to be at serious risk of bias. One study evaluated antithrombin concentrates compared to no antithrombin concentrates. We are uncertain whether antithrombin concentrates have an effect on all-cause mortality (risk ratio (RR) 0.55, 95% confidence interval (CI) 0.26 to 1.19 (intention-to-treat analysis); one study, 40 participants; very low certainty of evidence). We are uncertain whether antithrombin concentrates have an effect on venous thromboembolism-related mortality (RR 0.10, 95% CI 0.01 to 1.94 (intention-to-treat analysis); one study, 40 participants; very low certainty of evidence). We do not know whether antithrombin concentrates have an effect on major bleeding, clinically relevant non-major bleeding, and quality of life in adults with ALL treated with asparaginase-based chemotherapy, as data were insufficient. The remaining study (224 participants) evaluated prophylaxis with low-molecular-weight heparin versus no prophylaxis. However, this study reported insufficient data regarding harms including all-cause mortality, major bleeding, venous thromboembolism-related mortality, clinically relevant non-major bleeding, heparin-induced thrombocytopenia, and quality of life. In the sensitivity analysis of harms, exploring the effect of confounding, we also included nine non-randomised studies with outcomes judged to be at critical risk of bias primarily due to uncontrolled confounding. Three studies (179 participants) evaluated the effect of antithrombin concentrates and six studies (1224 participants) evaluated the effect of prophylaxis with different types of heparins. When analysing all-cause mortality; venous thromboembolism-related mortality; and major bleeding (studies of heparin only) including all studies with extractable outcomes for each comparison (antithrombin and low-molecular-weight heparin), we observed small study sizes; few events; wide CIs crossing the line of no effect; and substantial heterogeneity by visual inspection of the forest plots. Although the observed heterogeneity could arise through the inclusion of a small number of studies with differences in participants; interventions; and outcome assessments, the likelihood that bias due to uncontrolled confounding was the cause of heterogeneity is inevitable. Subgroup analyses were not possible due to insufficient data.  AUTHORS' CONCLUSIONS: We do not know from the currently available evidence, if thromboprophylaxis used for adults with ALL treated according to asparaginase-based regimens is associated with clinically appreciable benefits and acceptable harms. The existing research on this question is solely of non-randomised design, seriously to critically confounded, and underpowered with substantial imprecision. Any estimates of effect based on the existing insufficient evidence is very uncertain and is likely to change with future research.

Venous Thromboembolism Events Following Venovenous Extracorporeal Membrane Oxygenation for Severe Acute Respiratory Syndrome Coronavirus 2 Based on CT Scans

OBJECTIVES

The main objective of the study was to determine the prevalence of venous thromboembolism events in patients infected with severe acute respiratory syndrome coronavirus 2 requiring venovenous extracorporeal membrane oxygenation. The secondary objective was to compare venous thromboembolism events and coagulation variables in patients requiring venovenous extracorporeal membrane oxygenation according to the pathogen.

DESIGN

Retrospective observational analysis at a single center.

SETTING

Tertiary referral university teaching hospital.

PATIENTS

Patients with severe acute respiratory syndrome coronavirus 2-related severe acute respiratory distress syndrome requiring venovenous extracorporeal membrane oxygenation therapy with an injected CT scan performed after extracorporeal membrane oxygenation retrieval.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

We included 13 severe acute respiratory syndrome coronavirus 2 patients requiring venovenous extracorporeal membrane oxygenation. All of these patients experienced venous thromboembolism: 10 patients (76.9%) had isolated cannula-associated deep vein thrombosis, two patients (15.4%) had isolated pulmonary embolism, and one patient (7.7%) had both cannula-associated deep vein thrombosis and pulmonary embolism. Eleven patients (84.6%) had cannula-associated deep vein thrombosis. A jugular associated cannula-associated deep vein thrombosis was identified in seven patients (53.8%), a femoral associated cannula-associated deep vein thrombosis was identified in 10 patients (76.9%), and six patients (46.2%) had both femoral and jugular cannula-associated deep vein thrombosis. A pulmonary embolism was found in three patients (23.1%). No patient had central venous catheter-related deep vein thrombosis. One patient had thrombotic occlusion of the centrifugal pump, and one had oxygenator thrombosis requiring circuit replacement. Three patients (23.1%) had significant bleeding. Three patients (23.1%) had laboratory-confirmed heparin-induced thrombocytopenia, and all of them developed cannula-associated deep vein thrombosis. These three patients had femoral cannula-associated deep vein thrombosis, and two had an oxygenator or pump thrombosis. The mean activated partial thromboplastin time ratio was higher in the severe acute respiratory syndrome coronavirus 2 group than in the influenza group and the community-acquired pneumonia group (1.91 vs 1.48 vs 1.53; p = 0.001), which was also found in regard to the percentage of patients with an activated partial thromboplastin time ratio greater than 1.8 (47.8% vs 20% vs 20.9%; p = 0.003) and the mean prothrombin ratio (86.3 vs 61.6 vs 67.1; p = 0.003). There was no difference in baseline characteristics or venous thromboembolism events.

CONCLUSIONS

We report a 100% occurrence of venous thromboembolism in critically ill patients supported by venovenous extracorporeal membrane oxygenation for severe acute respiratory syndrome coronavirus 2-related acute respiratory distress syndrome using CT scan imaging despite a high target and close monitoring of anticoagulation.

Von Willebrand factor (vWF): marker of endothelial damage and thrombotic risk in COVID-19?

BACKGROUND

COVID-19 infection is characterised, among other features, by a prothrombotic state with high rate of venous thromboembolism (VTE), D-dimer, and fibrinogen levels. Clinical observations have also highlighted that these patients have elevated von Willebrand factor (vWF) and factor VIIIc.

METHODS

24 consecutive COVID-19 positive patients were selected from the intensive care unit (ICU) or the high acuity ward of Brighton and Sussex University Hospitals NHS Trust.

RESULTS

The rate of VTE was 25% and mortality rate was 16.7%. Fibrinogen and D-Dimers were elevated, 7.9 (1.6) g/L and 2.4 (2.02) ug/ml respectively. Factor VIIIc and von vWF antigen levels were both extremely elevated at 279 (148) u/dL and 350 (131) % respectively, which are comparable to levels seen in ICU patients with severe sepsis. vWF levels were significantly higher in patients that died (p=0.017) and showed a positive correlation with age. There was a statistically significant association between COVID-19 disease and non-O blood group (p=0.02); 80% (4/5) of COVID-19 patients with VTE were blood group A.

CONCLUSION

Very high levels of vWF and factor VIIIc are common in COVID-19 patients, comparable to levels in severely septic non-COVID ICU patients. This could contribute to the hypercoagulable state and increased VTE rate in COVID-19. Further studies are needed to evaluate the use of vWF for stratifying thrombotic risk in COVID-19 and to determine if elevated vWF is contributing to disease pathogenesis.

Autopsy Findings and Venous Thromboembolism in Patients With COVID-19: A Prospective Cohort Study

BACKGROUND

The new coronavirus, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has caused more than 210 000 deaths worldwide. However, little is known about the causes of death and the virus's pathologic features.

OBJECTIVE

To validate and compare clinical findings with data from medical autopsy, virtual autopsy, and virologic tests.

DESIGN

Prospective cohort study.

SETTING

Autopsies performed at a single academic medical center, as mandated by the German federal state of Hamburg for patients dying with a polymerase chain reaction-confirmed diagnosis of COVID-19.

PATIENTS

The first 12 consecutive COVID-19-positive deaths.

MEASUREMENTS

Complete autopsy, including postmortem computed tomography and histopathologic and virologic analysis, was performed. Clinical data and medical course were evaluated.

RESULTS

Median patient age was 73 years (range, 52 to 87 years), 75% of patients were male, and death occurred in the hospital (n = 10) or outpatient sector (n = 2). Coronary heart disease and asthma or chronic obstructive pulmonary disease were the most common comorbid conditions (50% and 25%, respectively). Autopsy revealed deep venous thrombosis in 7 of 12 patients (58%) in whom venous thromboembolism was not suspected before death; pulmonary embolism was the direct cause of death in 4 patients. Postmortem computed tomography revealed reticular infiltration of the lungs with severe bilateral, dense consolidation, whereas histomorphologically diffuse alveolar damage was seen in 8 patients. In all patients, SARS-CoV-2 RNA was detected in the lung at high concentrations; viremia in 6 of 10 and 5 of 12 patients demonstrated high viral RNA titers in the liver, kidney, or heart.

LIMITATION

Limited sample size.

CONCLUSION

The high incidence of thromboembolic events suggests an important role of COVID-19-induced coagulopathy. Further studies are needed to investigate the molecular mechanism and overall clinical incidence of COVID-19-related death, as well as possible therapeutic interventions to reduce it.

PRIMARY FUNDING SOURCE

University Medical Center Hamburg-Eppendorf.

Coagulopathy in COVID-19 and Its Implication for Safe and Efficacious Thromboprophylaxis

The novel coronavirus, SARS-CoV-2, is causing a global pandemic of life-threatening multiorgan disease, called COVID-19. Accumulating evidence indicates that patients with COVID-19 are at significant risk of thromboembolic complications, mainly affecting the venous, but also the arterial vascular system. While the risk of venous thromboembolism (VTE) appears to be higher in patients requiring intensive care unit support compared to those admitted to general wards, recent autopsy findings and data on the timing of VTE diagnosis relative to hospitalization clearly suggest that thromboembolic events also contribute to morbidity and mortality in the ambulatory setting. In addition to a severe hypercoagulable state caused by systemic inflammation and viral endotheliitis, some patients with advanced COVID-19 may develop a coagulopathy, which meets established laboratory criteria for disseminated intravascular coagulation, but is not typically associated with relevant bleeding. Similar to other medical societies, the Society of Thrombosis and Haemostasis Research has issued empirical recommendations on initiation, dosing, and duration of pharmacological VTE prophylaxis in COVID-19 patients.

Low venous thromboembolism incidence in high risk medical patients in an Israeli hospital. Can risk assessment be extrapolated to different populations?

BACKGROUND

Guidelines recommend venous thromboembolism (VTE) prophylaxis in hospitalized medical patients with Padua prediction score (PPS) ≥4 points. This recommendation is based on the high risk of symptomatic VTE observed among these patients in the Italian PPS derivation study, and the fivefold risk reduction with VTE-prophylaxis. This study aims to assess the incidence of VTE in high risk medical patients in a medium sized hospital in Israel.

METHOD

In this retrospective cohort study, data was collected of all medical patients hospitalized between January and June 2014. Patients were classified into low and high risk groups according to their PPS score, and according to whether they received anticoagulant thromboprophylaxis for VTE. Patients were further randomly selected to compare high risk patients that did or did not receive anticoagulant thromboprophylaxis. We further compared VTE incidence in high and low risk patients not treated with thromboprophylaxis. A search was conducted for diagnoses of venous thromboembolism and death during hospitalization and the following 90 days.

RESULTS

568 high risk patients (PPS ≥4 points) were included, 284 treated with prophylactic anticoagulation and 284 not. There were no VTE events in either group. There was no difference in mortality. A total of 642 non anticoagulated patients were randomly selected, 474 low risk and 168 high risk. There were no VTE events in either group.

CONCLUSIONS

The risk of VTE appears to be very low in our study, suggesting that among medical patients with PPS ≥4, the risk of VTE may differ dramatically between populations.

Rivaroxaban or Enoxaparin in Nonmajor Orthopedic Surgery

BACKGROUND

Nonmajor orthopedic surgery of the lower limbs that results in transient reduced mobility places patients at risk for venous thromboembolism. Rivaroxaban may be noninferior to enoxaparin with regard to the prevention of major venous thromboembolism in these patients.

METHODS

In this international, parallel-group, randomized, double-blind, noninferiority trial, we randomly assigned adult patients undergoing lower-limb nonmajor orthopedic surgery who were considered to be at risk for venous thromboembolism on the basis of the investigator's judgment to receive either rivaroxaban or enoxaparin. The primary efficacy outcome of major venous thromboembolism was a composite of symptomatic distal or proximal deep-vein thrombosis, pulmonary embolism, or venous thromboembolism-related death during the treatment period or asymptomatic proximal deep-vein thrombosis at the end of treatment. A test for superiority was planned if rivaroxaban proved to be noninferior to enoxaparin. For all outcomes, multiple imputation was used to account for missing data. Prespecified safety outcomes included major bleeding (fatal, critical, or clinically overt bleeding or bleeding at the surgical site leading to intervention) and nonmajor clinically relevant bleeding.

RESULTS

A total of 3604 patients underwent randomization; 1809 patients were assigned to receive rivaroxaban, and 1795 to receive enoxaparin. Major venous thromboembolism occurred in 4 of 1661 patients (0.2%) in the rivaroxaban group and in 18 of 1640 patients (1.1%) in the enoxaparin group (risk ratio with multiple imputation, 0.25; 95% confidence interval, 0.09 to 0.75; P<0.001 for noninferiority; P = 0.01 for superiority). The incidence of bleeding did not differ significantly between the rivaroxaban group and the enoxaparin group (1.1% and 1.0%, respectively, for major bleeding or nonmajor clinically relevant bleeding; 0.6% and 0.7%, respectively, for major bleeding).

CONCLUSIONS

Rivaroxaban was more effective than enoxaparin in the prevention of venous thromboembolic events during a period of immobilization after nonmajor orthopedic surgery of the lower limbs. (Funded by Centre Hospitalier Universitaire de Saint-Etienne and Bayer; PRONOMOS ClinicalTrials.gov number, NCT02401594.).

Venous Thromboembolism Complicated with COVID-19: What Do We Know So Far?

Coronavirus disease (COVID-19) is caused by the novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and is responsible for the ongoing 2019-2020 pandemic. Venous thromboembolism (VTE), a frequent cardiovascular and/or respiratory complication among hospitalized patients, is one of the known sequelae of the illness. Hospitalized COVID-19 patients are often elderly, immobile, and show signs of coagulopathy. Therefore, it is reasonable to assume a high incidence of VTE among these patients. Presently, the incidence of VTE is estimated at around 25% of patients hospitalized in the intensive care unit for COVID-19 even under anticoagulant treatment at prophylactic doses. In this review, we discuss present knowledge of the topic, the unique challenges of diagnosis and treatment of VTE, as well as some of the potential mechanisms of increased risk for VTE during the illness. Understanding the true impact of VTE on patients with COVID-19 will potentially improve our ability to reach a timely diagnosis and initiate proper treatment, mitigating the risk for this susceptible population during a complicated disease.

Sex-Specific SARS-CoV-2 Mortality: Among Hormone-Modulated ACE2 Expression, Risk of Venous Thromboembolism and Hypovitaminosis D

Severe acute respiratory syndrome coronavirus (SARS-CoV-2) disease (COVID-19) appears to have a higher mortality rate in presence of comorbidities and in men. The latter suggests the presence of a possible sex-dependent susceptibility. An enzymatic system involved in this different predisposition could be represented by angiotensin converting enzyme 2 (ACE2). ACE2 is activated and down-regulated by the spike protein of the virus and allows the penetration of SARS-CoV-2 into epithelial cells and myocardium. Data on the experimental animal have shown that 17ß-estradiol increases the expression and activity of ACE2 in both adipose tissue and kidney. Spontaneously hypertensive male mice have a higher myocardial ACE2 expression than females and its levels decrease after orchiectomy. In addition to this first aspect, the recent evidence of an increased frequency of venous thromboembolism in patients with COVID-19 (a clinical element associated with a worse prognosis) calls the attention on the safety of treatment with testosterone, in particular in hypogonadal men with greater genetic predisposition. Evidence that sex hormones are able to modulate the expression of ACE2 could help in interpreting epidemiological results and in designing more appropriate intervention strategies. Moreover, the vitamin D deficiency in elderly men may be worthy of further study regarding the epidemiological aspects of this different susceptibility and lethality between sexes.

Anticoagulants' Safety and Effectiveness in General Practice: A Nationwide Prospective Cohort Study

PURPOSE

Most real-world studies on anticoagulants have been based on health insurance databases or performed in secondary care. The aim of this study was to compare safety and effectiveness between patients treated with vitamin K antagonists (VKAs) and patients treated with direct oral anticoagulants (DOACs) in a general practice setting.

METHODS

The CACAO study (Comparison of Accidents and their Circumstances with Oral Anticoagulants) is a multicenter prospective cohort study conducted among ambulatory patients taking an oral anticoagulant. Participants were patients from the study's cross-sectional phase receiving oral anticoagulants because of nonvalvular atrial fibrillation, for secondary prevention of venous thromboembolism, or both. They were followed as usual for 1 year by their general practitioners, who collected data on changes in therapy, thromboembolic events, bleeding, and deaths. All events were adjudicated by an independent committee. We used a propensity score and a Cox regression model to derive hazard ratios.

RESULTS

Between April and December 2014, a total of 3,082 patients were included. At 1 year, 42 patients (1.7%) had experienced an arterial or venous event; 151 (6.1%) had experienced bleeding, including 47 (1.9%) who experienced major bleeding; and 105 (4.1%) had died. There was no significant difference between the VKA and DOAC groups regarding arterial or venous events, or major bleeding. The VKA group had a lower risk of overall bleeding (hazard ratio = 0.65; 95% CI, 0.43-0.98) but twice the risk of death (hazard ratio = 1.98; 95% CI, 1.15-3.42).

CONCLUSIONS

VKAs and DOACs had fairly similar safety and effectiveness in general practice. The substantially higher incidence of deaths with VKAs is consistent with known data from health insurance databases and calls for further research to understand its cause.

Venous thromboembolism rates after hip and knee arthroplasty and hip fractures

BACKGROUND

The ideal thromboprophylaxis regime following lower limb arthroplasty and proximal femur fractures remains controversial. Guidelines disagree on the type of chemical prophylaxis, its dose or duration. This article describes a method of monitoring venous thromboembolism (VTE) rates following Total Hip (THA), Total Knee Arthroplasty (TKA) and surgery for hip fractures (NOF#).

METHODS

Over 3 years, all patients investigated for VTE were analysed using Picture Archiving Communications System (PACS). All positive scans were then cross-referenced using PACS and local registry data to see if they had undergone THA, TKA or NOF# in the preceding 90 days. Mortality data were obtained from the national administrative database, Hospital Episode Statistics.

RESULTS

Five thousand seven hundred eighty-eight patients underwent investigation for VTE and there were 29 diagnoses of PE and 24 of DVT. There was a 0.77% rate of symptomatic DVT after THA, 0.05% after TKA and 0.55% after NOF #. The rate of confirmed symptomatic PE for THA was 0.46, 0.27% for TKA and 0.96% for NOF #. Mortality at one-year post-THA was 0.6, 0.6% for TKA and 25.9% after NOF#. All patients contacted either remained within the catchment area for the minimum 90 postoperative days or died within the catchment area.

CONCLUSIONS

The 90 day post-operative prevalence of symptomatic VTE of 1.2, 0.3 and 1.5% in THA, TKA and NOF # respectively are similar to other studies using symptomatic and imaging positive VTE as their endpoint. The study uses a method of collecting data which can be utilised in centres where PACS is available.

Net-clinical benefit of extended prophylaxis of venous thromboembolism with betrixaban in medically ill patients aged 80 or more

BACKGROUND

Extended-duration thromboprophylaxis with betrixaban reduces the risk of venous thromboembolism (VTE) without increasing major bleeding rates in acutely ill medical patients as compared to standard duration enoxaparin. We aimed to assess the risk-benefit of betrixaban in patients aged ≥ 80 years enrolled in the APEX trial.

METHODS

APEX was a randomized, double-blind trial in which patients hospitalized for acute medical illnesses received enoxaparin 40 mg qd for 10 ± 4 days or oral betrixaban 80 mg qd for 35 to 42 days. The primary efficacy outcome was VTE, the principal safety outcome was major bleeding. Net clinical benefit (NCB) was defined by the occurrence of VTE or major bleeding.

RESULTS

Of 7513 patients enrolled in the APEX trial, 2781 (37%) were aged ≥ 80 years. In this subgroup, VTE or major bleeding occurred in 7.0% of betrixaban patients and in 8.4% of enoxaparin patients, for a relative risk in the NCB of 0.82 (95% confidence interval 0.62-1.10). The relative risk reduction obtained with betrixaban was similar between those aged ≥ 80 years and patients younger than 80 years (5.0% and 6.7%, respectively, NCB 0.75, 0.58-0.96, P = .024), with no significant interaction across age groups (P = .33).

CONCLUSIONS

Event rates were higher in medically ill patients aged ≥ 80 years enrolled in the APEX study than in patients younger than 80 years. The predefined NCB was reduced with extended betrixaban therapy in both groups with no signs of age-related interactions. However, the primary efficacy endpoint was not achieved with betrixaban for patients 80 years of age or older.

Effectiveness and safety of inpatient versus extended venous thromboembolism (VTE) prophylaxis with heparin following major pelvic surgery for malignancy: protocol for a systematic review

BACKGROUND

Venous thromboembolism (VTE) is a common postoperative complication associated with significant morbidity and mortality. The use of prophylactic heparin postoperatively reduces this risk, and the use of extended duration prophylaxis is becoming increasingly common. Malignancy and pelvic surgery both independently further increase the risk of postoperative VTE and patients undergoing major pelvic surgery for malignancy are at particularly high risk of VTE. However, the optimum duration of prophylaxis specifically in this population currently remains unclear.

METHODS

We will conduct a systematic review of literature in accordance with the Cochrane Handbook for Systematic Reviews of Interventions (Higgins JPT, Green S. Cochrane Handbook for Systematic Reviews of Interventions version 5.1.0.,2011) to evaluate current evidence of the effectiveness and safety of inpatient versus extended VTE prophylaxis with heparin (all forms) following major pelvic surgery for malignancy. We will search PubMed, EMBASE, and the Cochrane Library. Regarding safety, Food and Drug Administration (FDA), and Therapeutic Goods Administration (TGA) websites will be searched, including all levels of evidence. Results will be the postoperative timeframe in which a VTE event can be considered to have been provoked by the surgery, and the number of patients needed to treat with both inpatient and extended prophylaxis to prevent a VTE event in this timeframe, comparing these to determine if there is a significant benefit from extended prophylaxis.

DISCUSSION

This systematic review will aim to identify the postoperative period in which patients undergoing major pelvic surgery for malignancy are at further increased risk of VTE as a result of their surgery and the optimum duration of heparin VTE prophylaxis with heparin to reduce this risk. Determining this will allow evidence-based recommendations to be made for the optimum duration of heparin VTE prophylaxis post major pelvic surgery for malignancy, leading to improved standards of care that are consistent between different providers and institutions.

SYSTEMATIC REVIEW REGISTRATION

In accordance with guidelines, our systematic review was submitted to PROSPERO for consideration of registration on 16/12/17 and was registered on 12/1/18 with the registration number CRD42018068961 , and it was last updated on December 1, 2018.

NCCN Guidelines Insights: Cancer-Associated Venous Thromboembolic Disease, Version 2.2018

Venous thromboembolism (VTE) is common in patients with cancer and increases morbidity and mortality. VTE prevention and treatment are more complex in patients with cancer. The NCCN Guidelines for Cancer-Associated Venous Thromboembolic Disease outline strategies for treatment and prevention of VTE in adult patients diagnosed with cancer or in whom cancer is clinically suspected. These NCCN Guidelines Insights explain recent changes in anticoagulants recommended for the treatment of cancer-associated VTE.

Statin and all-cause mortality in patients receiving anticoagulant therapy for venous thromboembolism. Data from the RIETE registry

BACKGROUND

The clinical outcomes during the course of anticoagulation in patients with venous thromboembolism (VTE) using statins remain controversial.

METHODS

We used the RIETE (Registro Informatizado Enfermedad TromboEmbólica) registry to compare the risk for VTE recurrences, major bleeding or death during anticoagulation, according to the use of statins at baseline. We used propensity score-matching (PSM) to adjust for confounding variables.

RESULTS

From February 2009 to January 2018, 32,062 VTE patients were included. Of these, 7,085 (22%) were using statins. Statin users were 10 years older (73±11 vs. 63±19 years, respectively) and more likely to have comorbidities or to be using antiplatelets or corticosteroids at baseline than non-users. During the course of anticoagulation (median, 177 days), 694 patients developed VTE recurrences, 848 bled and 3,169 died (fatal pulmonary embolism 176, fatal bleeding 121). Statin users had a similar rate of VTE recurrences (hazard ratio [HR]: 0.98; 95%CI: 0.82-1.17), a higher rate of major bleeding (HR: 1.29; 95%CI: 1.11-1.50) and a similar mortality rate (HR: 1.01; 95%CI: 0.93-1.10) than non-users. On PSM analysis, statin users had a significantly lower risk for death (HR: 0.62; 95%CI: 0.48-0.79) and a similar risk for VTE recurrences (HR: 0.98; 95%CI: 0.61-1.57) or major bleeding (HR: 0.85; 95%CI: 0.59-1.21) than non-users.

CONCLUSIONS

During anticoagulation for VTE, patients using statins at baseline had a lower risk to die than non-users.

Definitions, adjudication, and reporting of pulmonary embolism-related death in clinical studies: A systematic review

BACKGROUND

Pulmonary embolism (PE)-related death is a component of the primary outcome in many venous thromboembolism (VTE) studies. The absence of a standardized definition for PE-related death hampers study outcome evaluation and between-study comparisons.

OBJECTIVES

To summarize definitions for PE-related death used in recent VTE studies and to assess the PE-related death rate.

PATIENTS/METHODS

A systematic literature search was conducted on 26 April 2018 from 1 January 2014 up to the search date in MEDLINE, Embase, and CENTRAL. Cohort studies and randomized trials in which PE-related death was included in the primary outcome were eligible. Screening of titles, abstracts, and full-text articles, and data extraction were independently performed in duplicate by two authors. Study outcomes included the definition for PE-related death, VTE case-fatality rate, and death due to PE rate. Descriptive statistics were used to analyze the data.

RESULTS

Of the 6807 identified citations, 83 studies were included of which 27% were randomized trials, 31% were prospective, and 42% retrospective cohort studies. Thirty-five studies (42%) had a central adjudication committee. Thirty-eight (46%) reported a definition for PE-related death of which the most frequently used components were "autopsy-confirmed PE" (50%), "objectively confirmed PE before death" (55%), and "unexplained death" (58%). Median VTE case-fatality rate was 1.8% (interquartile range, 0.0-13).

CONCLUSIONS

Only half of the included studies reported definitions for PE-related death, which were very heterogeneous. Case-fatality rate of VTE events varied widely across studies. Standardization of the definition and guidance on adjudication and reporting of PE-related death is needed.

Venous and Lung Thromboembolism in the Context of Lung Cancer: Clinical Manifestations, Risk Factors and Prognosis

INTRODUCTION

The relationship between cancer and thromboembolic events has been known for a long time. Lung and venous thromboembolism are frequent complications of lung cancer and its treatment, being a great cause of morbidity and mortality. We pretend to establish the relationship between lung and venous thromboembolism and lung cancer, describe patient characteristics and analyze the impact in the survival and prognosis.

MATERIAL AND METHODS

It was a retrospective study. All research subjects were selected from lung cancer patients with a newly diagnosed lung and venous thromboembolism event admitted to Hospital S. João, between January 2008 and December 2013 and were followed until December 2014. Statistical analysis was performed with SPSS.

RESULTS

From the search, we obtained 113 patients. The majority was male, smokers or ex-smokers, and adenocarcinoma was the most frequent histologic type, being diagnosed mostly in advanced stages. We noticed that the median time between lung cancer diagnosis and lung venous thromboembolism was 2.9 months. In 24 patients (21.4%), the lung cancer diagnosis occurred after the lung and venous thromboembolism event and in 86 patients (76.8%), it occurred before the event. After a median follow up of 1.4 months, 107 (94.7%) patients died, 1 (0.9%) was lost to follow-up and 5 (4.4%) were still alive. The median survival rate was 1.5 months.

DISCUSSION

The diagnosis of lung and venous thromboembolism in patients with lung cancer is associated with bad prognosis. It occurs most frequently in patients with advanced disease, in the first months after lung cancer diagnosis and after beginning chemotherapy.

CONCLUSION

Disease progression is an independent predictor with negative impact in overall survival.

Effect of Low-Intensity vs Standard-Intensity Warfarin Prophylaxis on Venous Thromboembolism or Death Among Patients Undergoing Hip or Knee Arthroplasty: A Randomized Clinical Trial

IMPORTANCE

The optimal international normalized ratio (INR) to prevent venous thromboembolism (VTE) in warfarin-treated patients with recent arthroplasty is unknown.

OBJECTIVE

To determine the safety and efficacy of a target INR of 1.8 vs 2.5 for VTE prophylaxis after orthopedic surgery.

DESIGN, SETTING, AND PARTICIPANTS

The randomized Genetic Informatics Trial (GIFT) of Warfarin to Prevent Deep Vein Thrombosis enrolled 1650 patients aged 65 years or older initiating warfarin for elective hip or knee arthroplasty at 6 US medical centers. Enrollment began in April 2011 and follow-up concluded in October 2016.

INTERVENTIONS

In a 2 × 2 factorial design, participants were randomized to a target INR of 1.8 (n = 823) or 2.5 (n = 827) and to either genotype-guided or clinically guided warfarin dosing. For the first 11 days of therapy, open-label warfarin dosing was guided by a web application.

MAIN OUTCOMES AND MEASURES

The primary outcome was the composite of VTE (within 60 days) or death (within 30 days). Participants underwent screening duplex ultrasound postoperatively. The hypothesis was that an INR target of 1.8 would be noninferior to an INR target of 2.5, using a noninferiority margin of 3% for the absolute risk of VTE. Secondary end points were bleeding and INR values of 4 or more.

RESULTS

Among 1650 patients who were randomized (mean age, 72.1 years; 1049 women [63.6%]; 1502 white [91.0%]), 1597 (96.8%) received at least 1 dose of warfarin and were included in the primary analysis. The rate of the primary composite outcome of VTE or death was 5.1% (41 of 804) in the low-intensity-warfarin group (INR target, 1.8) vs 3.8% (30 of 793) in the standard-treatment-warfarin group (INR target, 2.5), for a difference of 1.3% (1-sided 95% CI, -∞ to 3.05%, P = .06 for noninferiority). Major bleeding occurred in 0.4% of patients in the low-intensity group and 0.9% of patients in the standard-intensity group, for a difference of -0.5% (95% CI, -1.6% to 0.4%). The INR values of 4 or more occurred in 4.5% of patients in the low-intensity group and 12.2% of the standard-intensity group, for a difference of -7.8% (95% CI, -10.5% to -5.1%).

CONCLUSIONS AND RELEVANCE

Among older patients undergoing hip or knee arthroplasty and receiving warfarin prophylaxis, an international normalized ratio goal of 1.8 compared with 2.5 did not meet the criterion for noninferiority for risk of the composite outcome of VTE or death. However, the trial may have been underpowered to meet this criterion and further research may be warranted.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT01006733.

Long-term rivaroxaban for the treatment of acute venous thromboembolism in patients with active cancer in a prospective multicenter trial

BACKGROUND/AIMS

Limited data are available regarding the efficacy of rivaroxaban for the treatment of cancer-associated venous thromboembolism (VTE). The aim of this study was to evaluate the effectiveness and safety of rivaroxaban for the treatment of VTE in active cancer patients.

METHODS

In this prospective, multicenter, open-label trial (NCT01989845), we enrolled patients with active cancer and objectively diagnosed lower-extremity deep vein thrombosis, pulmonary embolism (PE), or both from November 2013 to June 2016. Active cancer was defined as a histologically confirmed malignancy, which was diagnosed or treated within the previous 6 months, or as a recurrent/ metastatic cancer. Patients received oral rivaroxaban 15 mg twice daily for first 3 weeks, followed by 20 mg once daily for 6 months. The primary outcome was the symptomatic recurrent VTE and the secondary outcomes included any recurrent VTE, major or clinically relevant non-major (CRNM) bleeding events, and overall mortality. All study outcomes were validated by blinded central adjudication.

RESULTS

Of 124 patients enrolled, 110 (88.7%) had solid cancer, 93 (75.0%) had metastatic disease, and 110 (88.7%) were receiving chemotherapy or radiotherapy. During the 6-month study period, seven patients experienced symptomatic recurrent VTE (cumulative incidence, 5.9%), and two patients experienced incidental recurrent PE (cumulative incidence of any recurrent VTE, 7.6%). Major bleeding events occurred in six patients (cumulative incidence, 5.3%) and CRNM bleeding events in 11 patients (cumulative incidence, 10.2%). Twenty-eight patients (overall mortality, 24.0%) died.

CONCLUSION

Rivaroxaban is effective and safe for the treatment of VTE in patients with active cancer.

"Death Knell" for Prophylactic Vena Cava Filters? A 20-Year Experience with a Venous Thromboembolism Guideline

The role of prophylactic vena cava filters (pVCFs) in trauma patients remains controversial. After 20 years of data collection and experience, we reviewed our venous thromboembolism guideline for the efficacy of pVCFs in preventing pulmonary embolism (PE). A retrospective cohort study was performed using our Level I trauma center registry from January 1997 thru December 2016. This population was then divided by the presence of pVCFs. Univariate analysis was performed comparing the incidence of PEs, deep vein thrombosis, and mortality between those with and without a pVCF. There were 35,658 patients identified, of whom 2 per cent (n = 847) received pVCFs. The PE rate was 0.4 per cent in both groups. The deep vein thrombosis rate for pVCFs was 3.9 per cent compared with 0.6 per cent in the no-VCF group (P < 0.0001). Given that there was no difference in the rates of PEs between the cohorts, the subset of patients with a PE were analyzed by their risk factors. Only ventilator days > 3 were associated with a higher risk in the no-pVCF group (0.2 vs 1.5%, P = 0.033). pVCFs did not confer benefit reducing PE rate. In addition, despite their intended purpose, pVCFs cannot eliminate PEs in high-risk trauma patients, suggesting a lack of utility for prophylaxis in this population.

Influence of baseline anemia on long-term clinical outcomes in patients with venous thromboembolism: from the COMMAND VTE registry

The influence of anemia on the long-term clinical outcomes has not been fully evaluated in patients with venous thromboembolism (VTE). We evaluated the influence of anemia among 3012 patients in the COMMAND VTE Registry with a median follow-up period of 1219 days. The outcomes measures were ISTH major bleeding, recurrent VTE and all-cause death. There were 1012 patients (34%) with moderate/severe anemia (Hb ≤ 10.9 g/dl), 615 patients (20%) with mild anemia (Hb 11.0-12.9 g/dl for men, and 11.0-11.9 g/dl for women), and 1385 patients (46%) without anemia. The cumulative 5-year incidence of major bleeding was significantly higher in patients with anemia (moderate/severe anemia: 17.6%, mild anemia: 12.1%, and no anemia: 8.7%, P < 0.001). After adjusting the confounders, the excess risk of mild and moderate/severe anemia, respectively, relative to no anemia for major bleeding remained significant (mild: adjusted HR 1.41: [95% CI 1.00-1.98], P = 0.048; moderate/severe: adjusted HR 1.91: [95% CI 1.42-2.58], P < 0.001, respectively). The excess risk of moderate/severe anemia relative to no anemia was also significant for mortality (adjusted HR 2.89: 95% CI 2.45-3.42, P < 0.001), but the risk was neutral for recurrent VTE (adjusted HR 1.05: 95% CI 0.76-1.45, P = 0.77). In conclusions, VTE patients with mild and moderate/severe anemia had higher risk for major bleeding events without significant excess risk for recurrent VTE events, and the risk for major bleeding events increased according to the severity of anemia. We should pay more attention to the optimal intensity and duration of anticoagulation in VTE patients with anemia.

Periprocedural interruption of anticoagulation in patients with cancer-associated venous thromboembolism: An analysis of thrombotic and bleeding outcomes

Essentials Patients with cancer-associated VTE frequently undergo invasive procedures. Data on the perioperative interruption of anticoagulation for cancer-associated VTE are lacking. Patients with cancer-associated VTE experience high post-operative VTE and major bleeding rates. This patient population may warrant close follow-up after invasive procedures.

BACKGROUND

Patients with cancer are at high risk for venous thromboembolic events. Venous thromboembolism (VTE) can lead to significant morbidity among patients with cancer, and is estimated to be one of the leading causes of death among cancer patients. Patients with cancer often require invasive procedures for biopsy or therapeutic purposes. There is a lack of data on postoperative outcomes following interruption of anticoagulation in this population.

OBJECTIVE

To assess 30-day postoperative thromboembolic and major bleeding complication rates following the perioperative interruption of anticoagulation in patients with cancer-associated VTE.

METHODS

We conducted a retrospective self-controlled case series study with patients with cancer-associated VTE undergoing perioperative interruption of anticoagulation at a dedicated tertiary-care anticoagulation clinic for invasive procedures between January 2013 and March 2018. The primary efficacy and safety outcomes were the 30-day postoperative rates of VTE and major bleeding, respectively. The secondary outcomes included the 30-day rates of clinically relevant non-major bleeding (CRNMB) and overall mortality. Patients undergoing multiple perioperative anticoagulation interruptions were included.

RESULTS

One hundred and forty-six patients undergoing 171 periprocedural interruptions were included in our cohort. The 30-day rates of VTE and major bleeding were both 4.1% (95% confidence interval [CI] 2.0-8.2). The 30-day rate of CRNMB was 2.9% (95% CI 1.3-6.7) and the 30-day overall mortality rate was 0.6% (95% CI 0.1-3.4). There were no fatal postoperative VTE or major bleeding events.

CONCLUSIONS

The periprocedural interruption of anticoagulation in patients with cancer-associated VTE is associated with high postoperative rates of VTE and major bleeding. Patients with cancer-associated VTE may require closer follow-up for VTE and bleeding complications after invasive procedures.

Preventing hospital associated venous thromboembolism

An NHS success story that should be exported globally

The association of recurrence and bleeding events with mortality after venous thromboembolism: From the COMMAND VTE Registry

BACKGROUND

The duration of anticoagulation therapy after venous thromboembolism (VTE) should be based on the balance between risks of recurrent VTE and bleeding. However, there is uncertainty about the impact of these events on subsequent mortality.

METHODS

We evaluated the association of recurrent VTE and major bleeding events with mortality among 3026 patients in the COMMAND VTE Registry. We estimated the risks of the recurrent VTE events and the major bleeding events for subsequent mortality by the time-updated multivariable Cox proportional hazard model.

RESULTS

During the median follow-up period of 1218 days, 225 patients developed recurrent VTE events, 274 patients developed major bleeding events, and 763 patients died. The multivariable Cox proportional hazard model revealed that both the recurrent VTE and major bleeding events were strongly associated with subsequent mortality risk (recurrent VTE: HR 3.24, 95%CI 2.57-4.08, P < 0.001; major bleeding: HR 3.53, 95%CI 2.88-4.31, P < 0.001). Both the recurrent pulmonary embolism (PE) and recurrent deep vein thrombosis (DVT) events were associated with subsequent mortality risk (recurrent PE events: HR 4.42, 95%CI 3.28-5.95, P < 0.001; recurrent DVT events: HR 2.42, 95%CI 1.75-3.36, P < 0.001).

CONCLUSIONS

In the real-world patients with VTE, both the recurrent VTE events and the major bleeding events were strongly associated with subsequent mortality risk with the comparable effect size. The recurrent PE and recurrent DVT events were also associated with increased risks for mortality, although the magnitude of the effect on mortality was numerically greater with the recurrent PE events than with the recurrent DVT events.

Physical activity and risk of recurrence and mortality after incident venous thromboembolism

BACKGROUND

Limited data exist on the relationship between physical activity and major complications after incident venous thromboembolism (VTE).

OBJECTIVES

To investigate whether physical activity was associated with risk of recurrence and mortality in patients with VTE recruited from the general population.

METHODS

Patients with incident VTE (n = 786) derived from the Tromsø Study surveys 4-6 (1994-1995, 2001-2002, and 2007-2008) were included, and data on physical activity were dichotomized according to the activity level reported in the survey preceding the incident VTE (inactive: <1 hour per week, active: ≥1 hour per week). Recurrent VTE and all-cause mortality were registered up to December 31, 2015. Hazard ratios (HRs) for recurrence and all-cause mortality were calculated using Cox regression models with the inactive group as reference.

RESULTS

There were 139 recurrences and 395 deaths during follow-up. Physical activity was not associated with the risk of recurrence in men (HR model 2: 1.48, 95% confidence interval [CI] 0.83-2.65) or in women (HR model 2: 0.95, 95% CI 0.52-1.74). In contrast, physical activity was associated with a 28% lower risk of mortality during 10 years of follow up (HR model 3: 0.72, 95% CI 0.57-0.91). The inverse association was stronger in patients with a first deep vein thrombosis ( HR model 2: 0.59, 95% CI 0.44-0.79) than a pulmonary embolism (HR model 3: 0.87, 95% CI 0.61-1.26).

CONCLUSION

Our results suggest that habitual physical activity prior to incident VTE does not influence the risk of recurrence. In contrast, active individuals were at lower risk of mortality, particularly following deep vein thrombosis.

Cardiovascular and bleeding outcomes in a population-based cohort of patients with chronic immune thrombocytopenia

Essentials Immune thrombocytopenia (ITP) is an autoimmune disorder characterized by low platelet count. We conducted a cohort study of 3 584 chronic ITP patients from the Nordic countries. Cardiovascular events occurred across all platelet count levels. Cardiovascular or bleeding events were strong prognostic factors for all-cause mortality. Background Among patients with chronic immune thrombocytopenia (cITP), little is known regarding risk factors for cardiovascular and bleeding outcomes and how these events influence mortality. Objectives We examined the rate of cardiovascular events and bleeding requiring a hospital contact according to platelet count levels, as well as the prognostic impact of these events on all-cause mortality in adult patients with cITP. Methods We identified all cITP patients registered in the Nordic Country Patient Registry for Romiplostim during 1996 to 2015. Absolute risks and hazard ratios across platelet count levels based on Cox regression analysis were computed, adjusting for age, sex, prevalent/incident cITP, smoking, and comorbidities. We also compared all-cause mortality rates in cITP patients with and without cardiovascular and bleeding events. Results Among 3 584 cITP patients, 1-year risks were 1.9% for arterial cardiovascular events, 1.2% for venous thromboembolism, and 7.5% for bleeding. Rates of cardiovascular events were similar across platelet counts. Patients with platelet counts <50 × 109 /L had >2-fold higher rates of bleeding than patients with normal platelet counts. These associations were unchanged in time-varying analyses that considered changes in platelet counts during follow-up. Occurrences of cardiovascular and bleeding events were associated with 4-fold to 5-fold increases in 1-year mortality. Conclusions Among patients with cITP, the 1-year risks of cardiovascular events were 1% to 2%, while nearly 8% experienced a bleeding event within 1 year. Cardiovascular events occurred across all platelet levels, while low platelet counts were associated with increased hazards of bleeding. Cardiovascular and bleeding events were strong prognostic factors for mortality.

Venous thromboembolism following inpatient pediatric surgery: Analysis of 153,220 patients

PURPOSE

To evaluate venous thromboembolism (VTE) rates and risk factors following inpatient pediatric surgery.

METHODS

153,220 inpatient pediatric surgical patients were selected from the 2012-2015 NSQIP-P database. Demographic and perioperative variables were documented. Primary outcome was VTE requiring treatment within 30 postoperative days. Secondary outcomes included length of stay (LOS) and 30-day mortality. Prediction models were generated using logistic regression. Mortality and time to VTE were assessed using Kaplan-Meier survival analysis.

RESULTS

305 patients (0.20%) developed 296 venous thromboses and 12 pulmonary emboli (3 cooccurrences). Median time to VTE was 9 days. Most VTEs (81%) occurred predischarge. Subspecialties with highest VTE rates were cardiothoracic (0.72%) and general surgery (0.28%). No differences were seen for elective vs. urgent/emergent procedures (p = 0.106). All-cause mortality VTE patients was 1.2% vs. 0.2% in patients without VTE (p < 0.001). After stratifying by American Society of Anesthesiologists (ASA) class, no mortality differences remained when ASA < 3. Preoperative, postoperative, and total LOSs were longer for patients with VTE (p < 0.001 for each). ASA ≥ 3, preoperative sepsis, ventilator dependence, enteral/parenteral feeding, steroid use, preoperative blood transfusion, gastrointestinal disease, hematologic disorders, operative time, and age were independent predictors (C-statistic = 0.83).

CONCLUSIONS

Pediatric postsurgical patients have unique risk factors for developing VTE.

LEVEL OF EVIDENCE

Level II.

A high Gas6 level in plasma predicts venous thromboembolism recurrence, major bleeding and mortality in the elderly: a prospective multicenter cohort study

Essentials Predictive ability of pro-hemostatic Gas6 for recurrent venous thromboembolism (VTE) is unknown. We measured Gas6 levels in 864 patients with VTE over 3 years. High Gas6 (> 157%) at diagnosis is associated with VTE recurrence, major bleeding and mortality. Gas6 plasma levels measured 12 months after the index VTE are discriminatory for VTE recurrence. SUMMARY: Background Growth arrest-specific gene 6 (Gas6) is a prohemostatic protein with an unknown predictive ability for recurrent venous thromboembolism (VTE). In the elderly, VTE results in higher mortality but does not have a higher rate of recurrence than in younger patients. Consequently, anticoagulation management in the elderly is challenging. Objective To prospectively investigate the performance of Gas6 in predicting VTE recurrence, major bleeding and mortality in the elderly. Methods Consecutive patients aged ≥ 65 years with acute VTE were followed for a period of 3 years. Primary outcomes were symptomatic VTE recurrence, major bleeding, and mortality. Plasma Gas6 was measured with ELISA. Results Gas6 levels were measured in 864 patients at the time of the index VTE (T1) and, in 70% of them, also 12 months later (T2). The Gas6 level at T1 was discriminatory for VTE recurrence (C-statistic, 0.56; 95% confidence interval [CI] 0.51-0.62), major bleeding (0.60, 95% CI 0.55-0.65) and mortality (0.69, 95% CI 0.65-0.73) up to 36 months. VTE recurrence up to 24 months after T2 was discriminated by the Gas6 level at T2 (0.62, 95% CI 0.54-0.71). High Gas6 levels (> 157%) and continuous Gas6 levels at T1 were associated with VTE recurrence up to 6 months and 12 months, respectively. Conclusions In elderly patients, a high Gas6 level is associated with higher risks of VTE recurrence, major bleeding, and death. These findings support further studies to assess the performance of Gas6 in adjusting the length of anticoagulation.

Use of hormone replacement therapy and risk of venous thromboembolism: nested case-control studies using the QResearch and CPRD databases

OBJECTIVE

To assess the association between risk of venous thromboembolism and use of different types of hormone replacement therapy.

DESIGN

Two nested case-control studies.

SETTING

UK general practices contributing to the QResearch or Clinical Practice Research Datalink (CPRD) databases, and linked to hospital, mortality, and social deprivation data.

PARTICIPANTS

80 396 women aged 40-79 with a primary diagnosis of venous thromboembolism between 1998 and 2017, matched by age, general practice, and index date to 391 494 female controls.

MAIN OUTCOME MEASURES

Venous thromboembolism recorded on general practice, mortality, or hospital records. Odds ratios were adjusted for demographics, smoking status, alcohol consumption, comorbidities, recent medical events, and other prescribed drugs.

RESULTS

Overall, 5795 (7.2%) women who had venous thromboembolism and 21 670 (5.5%) controls had been exposed to hormone replacement therapy within 90 days before the index date. Of these two groups, 4915 (85%)and 16 938 (78%) women used oral therapy, respectively, which was associated with a significantly increased risk of venous thromboembolism compared with no exposure (adjusted odds ratio 1.58, 95% confidence interval 1.52 to 1.64), for both oestrogen only preparations (1.40, 1.32 to 1.48) and combined preparations (1.73, 1.65 to 1.81). Estradiol had a lower risk than conjugated equine oestrogen for oestrogen only preparations (0.85, 0.76 to 0.95) and combined preparations (0.83, 0.76 to 0.91). Compared with no exposure, conjugated equine oestrogen with medroxyprogesterone acetate had the highest risk (2.10, 1.92 to 2.31), and estradiol with dydrogesterone had the lowest risk (1.18, 0.98 to 1.42). Transdermal preparations were not associated with risk of venous thromboembolism, which was consistent for different regimens (overall adjusted odds ratio 0.93, 95% confidence interval 0.87 to 1.01).

CONCLUSIONS

In the present study, transdermal treatment was the safest type of hormone replacement therapy when risk of venous thromboembolism was assessed. Transdermal treatment appears to be underused, with the overwhelming preference still for oral preparations.

Management of venous thromboembolism in patients with cancer

Current guidelines for anticoagulant therapy do not so far suggest any form of differentiated approach to cancer patients with venous thromboembolism (VTE). This review article provides an overview of the published literature in cancer patients with VTE, mostly using data from the RIETE registry. Our findings provide some insights into what factors may be used to guide physicians in adapting recommended anticoagulant regimens to the individual patient, as oncologists are increasingly doing with cancer treatments. For instance, patients presenting with deep vein thrombosis (DVT) alone might benefit from curtailing treatment intensity as anticoagulant therapy progresses. The site of cancer also needs to be considered. In patients with incidental PE or splanchnic vein thrombosis, we should be more cautious before prescribing anticoagulant therapy. The optimal duration of anticoagulant therapy is unknown.

Breadth of complications of long-term oral anticoagulant care

The majority of patients with venous thromboembolism (VTE) have a considerable long-term risk of recurrence and may require extended duration of anticoagulant treatment after the initial 3 to 6 months. The decision to extend treatment is based not only on the individual risk of recurrence, but should also consider the potential complications associated with anticoagulation, taking into account that anticoagulant drugs are among the drugs most frequently associated with hospital admission due to adverse drug reactions. The most feared complication of oral anticoagulants is bleeding, which in some cases may be fatal or may affect critical organs. Case-fatality rates of bleeding have been reported to be ∼3 times higher than case-fatality rates of recurrent VTE. Even when nonserious, bleeding may require medical intervention and/or may impact on patient quality of life or working activity. Factors associated with bleeding during anticoagulant treatment include, among others, advanced age, cancer, renal or liver insufficiency, or concomitant antithrombotic drugs, but no bleeding risk score is sufficiently accurate for use in clinical practice. Not uncommonly, bleeding occurs as a complication of trauma or medically invasive procedures. Nonbleeding complications associated with oral anticoagulants are unusual, and their relevance is extremely uncertain, and include vascular calcification, anticoagulation-related nephropathy, and osteoporosis. Finally, because VTE not uncommonly affects young individuals and the mean age of the population is ∼60 years, the costs associated with extended anticoagulation should not be forgotten. The costs of the drugs need to be balanced against health outcome costs associated with both recurrent VTE and bleeding.