RE-COVERY DVT/PE: Rationale and design of a prospective observational study of acute venous thromboembolism with a focus on dabigatran etexilate

The Challenge of Intermediate-Risk Pulmonary Embolism

BACKGROUND

Intermediate-risk pulmonary embolism is a common disease that is associated with significant morbidity and mortality; however, a standardized treatment protocol is not well-established.

AREAS OF UNCERTAINTY

Treatments available for intermediate-risk pulmonary embolisms include anticoagulation, systemic thrombolytics, catheter-directed therapies, surgical embolectomy, and extracorporeal membrane oxygenation. Despite these options, there is no clear consensus on the optimal indication and timing of these interventions.

THERAPEUTIC ADVANCES

Anticoagulation remains the cornerstone of treatment for pulmonary embolism; however, over the past 2 decades, there have been advances in the safety and efficacy of catheter-directed therapies. For massive pulmonary embolism, systemic thrombolytics and, sometimes, surgical thrombectomy are considered first-line treatments. Patients with intermediate-risk pulmonary embolism are at high risk of clinical deterioration; however, it is unclear whether anticoagulation alone is sufficient. The optimal treatment of intermediate-risk pulmonary embolism in the setting of hemodynamic stability with right heart strain present is not well-defined. Therapies such as catheter-directed thrombolysis and suction thrombectomy are being investigated given their potential to offload right ventricular strain. Several studies have recently evaluated catheter-directed thrombolysis and embolectomies and demonstrated the efficacy and safety of these interventions. Here, we review the literature on the management of intermediate-risk pulmonary embolisms and the evidence behind those interventions.

CONCLUSIONS

There are many treatments available in the management of intermediate-risk pulmonary embolism. Although the current literature does not favor 1 treatment as superior, multiple studies have shown growing data to support catheter-directed therapies as potential options for these patients. Multidisciplinary pulmonary embolism response teams remain a key feature in improving the selection of advanced therapies and optimization of care.

Long-Term Exposure to Air Pollution and Incidence of Venous Thromboembolism in the General Population: A Population-Based Retrospective Cohort Study

To date, the relationship between air pollutants and venous thromboembolism (VTE) has not been well established. Our aim is to investigate the association between ambient air pollutants and the incidence of VTE using the Korean National Health Insurance Service-National Health Screening Cohort (NHIS-HEALS) database. From 2003 to 2015, 338,616 subjects from the general population not previously diagnosed with VTE were included. The long-term average concentration of air pollutants before diagnosis for each subject was calculated. During the study period, there were 3196 incident cases of VTE. After adjusting for age, gender, economic status, body mass index, physical activity, smoking, alcohol consumption, comorbid diseases, and meteorological variables, the risk of VTE was observed to increase significantly with the long-term average concentration of particulate matter < 10 μm in diameter: PM10 (hazard ratio (HR) = 1.064 (95% confidence interval [CI] 1.053−1.074) for 1 μg/m3), SO2 (HR = 1.118 (95% CI 1.079−1.158) 1 ppb), and O3 (HR = 1.039 (95% CI 1.026−1.053) for 1 ppb), respectively. A difference between the date of the health screening and the date of diagnosis of the disease was observed. Long-term exposure to air pollutants including PM10, SO2, and O3 may be an independent risk factor for the development of VTE.

Safety and effectiveness of dabigatran in routine clinical practice: the RE-COVERY DVT/PE study

RE-COVERY DVT/PE is a two-phase, international, observational study of anticoagulant therapy in patients with deep vein thrombosis and/or pulmonary embolism (DVT/PE). The objective of the second phase was to compare the safety and effectiveness of dabigatran versus a vitamin K antagonist (VKA) over 1 year of follow-up. Primary safety and effectiveness outcomes were major or clinically relevant nonmajor bleeding events (MBE/CRNMBEs) and symptomatic recurrent venous thromboembolism (VTE) (including deaths related to recurrent VTE). To minimize bias due to unbalanced patient characteristics, only patients in an overlapping range of estimated propensity scores were included (analytic set), and propensity score weighting was applied to compare outcomes. Outcome analysis used an as-treated approach, censoring patients after they stopped or switched their initial anticoagulant. Overall, 3009 patients enrolled from 2016 to 2018 were eligible: 60% were diagnosed with DVT alone, 21% with PE alone, and 19% with DVT plus PE. The analytic set consisted of 2969 patients. The incidence rate in %/year (95% confidence interval [CI]) of MBE/CRNMBEs was 2.63 (1.79-3.74) with dabigatran versus 4.48 (3.23-6.06) with warfarin; hazard ratio 0.63 (95% CI 0.32-1.25). For symptomatic recurrent nonfatal or fatal VTE the incidence rate was 1.53 (0.91-2.42) with dabigatran versus 2.01 (1.21-3.14) with VKAs; hazard ratio 0.78 (95% CI 0.30-2.02). In conclusion, we found lower annualized rates of MBE/CRNMBEs with dabigatran than VKA, although the difference was not statistically significant. Annualized rates of symptomatic VTE or related mortality were similar with dabigatran and VKA. These observational results with 1 year of follow-up reflect those of the randomized clinical trials. Trial registration: ClinicalTrials.gov identifier NCT02596230, first registered November 4, 2015.

Profile of Patients with Isolated Distal Deep Vein Thrombosis versus Proximal Deep Vein Thrombosis or Pulmonary Embolism: RE-COVERY DVT/PE Study

Isolated distal deep vein thrombosis (IDDVT) is presumed to be more benign than proximal DVT (PDVT) or pulmonary embolism (PE), suggesting a need for different management approaches. This subgroup analysis of the RE-COVERY DVT/PE global, observational study investigated patient characteristics, hospitalization details, and anticoagulant therapy in patients with IDDVT in real-world settings in 34 countries enrolled from January 2016 to May 2017. Data were analyzed descriptively according to the type and location of the index venous thromboembolism (VTE): IDDVT, PDVT ± distal DVT (DDVT), and PE ± DVT. Of the 6,095 eligible patients, 323 with DVT located outside the lower limb and no PE were excluded. Of the remaining 5,772 patients, 17.6% had IDDVT, 39.9% had PDVT ± DDVT, and 42.5% had PE ± DVT. IDDVT patients were younger and had fewer risk factors for VTE than the other groups. Other comorbidities were less frequent in the IDDVT group, except for varicose veins, superficial thrombophlebitis, and venous insufficiency. IDDVT patients were less likely to be diagnosed in an emergency department (22.3 vs. 29.7% for PDVT ± DDVT and 45.4% for PE ± DVT) or hospitalized for VTE (29.2 vs. 48.5% for PDVT ± DDVT and 75.0% for PE ± DVT). At hospital discharge or 14 days after diagnosis (whichever was later), non-vitamin K antagonist oral anticoagulants were the most commonly used anticoagulants (55.6% for IDDVT, 54.7% for PDVT ± DDVT, and 52.8% for PE ± DVT). Although differences in patient characteristics, risk factors, and clinical management were identified, anticoagulant treatment of IDDVT was almost equal to that of PDVT or PE. Prospective studies should investigate whether, in a global perspective, this is an appropriate use of anticoagulants. TRIAL REGISTRATION NUMBER:  ClinicalTrials.gov NCT02596230.

Are the correct outcomes being measured in studies of oral anticoagulants? A systematic survey

INTRODUCTION

Oral anticoagulant (OAC) intervention trials have typically included clinical event outcomes. However, there is no standard list of outcomes to be used in OAC research. This study aimed to describe and classify the outcomes used in recent prospective clinical studies involving OACs.

MATERIALS AND METHODS

We searched MEDLINE, EMBASE, and CINAHL databases from January 2009 to July 2019 for prospective studies with an intervention or control group that included one or more oral anticoagulants. We abstracted details about each included study and the outcomes used from the study report and its accompanying protocol. Using the Core Outcome Measures in Effectiveness Trials (COMET) Initiative recommendations, we categorised each outcome into one of five domains (mortality/survival, physiological/clinical, life impact, resource use, and adverse events). Our primary outcome was the prevalence of use of an outcome domain across studies.

RESULTS

We included 70 prospective studies, including 52 randomized controlled trials and 18 prospective cohort studies. A total of 121 different outcomes were reported. The COMET domains were represented in the 70 studies as follows: mortality (63/70, 90.0%); physiological/clinical domain (70/70, 100%), life impact domain (43/70, 61.4%), resource use domain (26/70, 37.1%), and adverse events domain (55/70, 78.6%).

CONCLUSION

Outcome reporting in prospective studies of OACs more frequently concentrates on mortality, physiological/clinical domains, and adverse events compared to life impact and resource utilization domains, the latter uncommonly used. A priority for future research includes developing a core outcome set (COS) for OAC research that represents all domains.

ETNA VTE Europe: A contemporary snapshot of patients treated with edoxaban in clinical practice across eight European countries

INTRODUCTION

Edoxaban has proven its efficacy and safety in the ENGAGE AF-TIMI 48 and HOKUSAI-VTE clinical trials. Clinical practice patients, however, may differ from those enolled in clinical trials. We aimed to compare patients from the HOKUSAI-VTE clinical trial with those treated in clinical practice.

MATERIALS AND METHODS

ETNA-VTE-Europe is a prospective, non-interventional post-authorisation safety study conducted in eight European countries.

RESULTS

A total of 2,879 patients presenting with acute symptomatic venous thromboembolism (VTE) were enrolled at 339 sites. Of the 2,680 patients with complete data, 23.6% reported prior VTE and 2.8% had a history of bleeding. Patients in ETNA-VTE were older (65vs.57 years), more likely to be female (46.5vs.39.8%) and had a higher prevalence of chronic venous insufficiency (11.1vs.1.6%) than those in the European cohort of the HOKUSAI-VTE trial (n=1,512). Bodyweight and creatinine clearance were substantially lower in clinical practice. Edoxaban dosing was adherent to label in 90% of patients, with higher (60 mg) and lower than recommended doses (30 mg) used in 6.6% and 3.3% of the patients, respectively. Heparin lead-in was used in 84.7% of the patients overall, and was more frequently used in patients with PE than patients with DVT only (91.3% vs. 80.1%; p<0.0001).

CONCLUSIONS

These data reinforce the largely appropriate use of edoxaban in routine clinical practice, where the study population differs from those in prior randomised controlled trials. CLINICALTRIALS.

GOV IDENTIFIER

NCT02943993.

Profile of patients diagnosed with acute venous thromboembolism in routine practice according to age and renal function: RE-COVERY DVT/PE study

Abstract

In randomized clinical trials (RCTs) of nonvitamin K antagonist oral anticoagulants (NOACs) for acute venous thromboembolism (VTE), ~ 12–13% of patients were elderly and ~ 26% had mild-to-moderate renal impairment. Observational studies are not restricted by the selection and treatment criteria of RCTs. In this ancillary analysis of the RE-COVERY DVT/PE global observational study, we aimed to describe patient characteristics, comorbidities, and anticoagulant therapy for subgroups of age (< or ≥ 75 years) and renal impairment (creatinine clearance [CrCl; estimated with Cockcroft–Gault formula] < 30 [severe], 30 to < 50 [moderate], 50 to < 80 [mild], ≥ 80 [normal] mL/min). Of 6095 eligible patients, 25.3% were aged ≥ 75 years; 38.2% (1605/4203 with CrCl values) had mild-to-moderate renal impairment. Comorbidities were more common in older patients (73.9% aged ≥ 75 vs. 58.1% < 75 years) and in those with mild or moderate versus no renal impairment (75.9%, 80.9%, and 59.3%, respectively). At hospital discharge or 14 days after diagnosis (whichever was later), most patients (53.7% and 55.1%, respectively) in both age groups received NOACs; 20.8% and 23.4%, respectively, received vitamin K antagonists, 19.0% and 21.8% parenteral therapy, 2.3% and 3.8% other anticoagulant treatments. Use of NOACs decreased with worsening renal impairment (none 58.5%, moderate 49.6%, severe 25.7%) and, in younger versus older patients with moderate renal impairment (33.1% vs. 56.1%). In routine practice, there are more elderly and renally impaired patients with VTE than represented in RCTs. Decreasing renal function, but not older age, was associated with less NOAC use. Clinical Trial Registration: http://www.clinicaltrials.gov. Unique identifier: NCT02596230.

Graphic abstract

Decreasing renal function, particularly in the subgroup with CrCl < 30 mL/min, but not older age, was associated with less use of nonvitamin K antagonist oral anticoagulants (NOACs). Nevertheless, more than half of the older patients with moderate renal impairment received a NOAC as their oral anticoagulant.

Profile of Patients Diagnosed With Acute Venous Thromboembolism in Routine Clinical Practice: The RE-COVERY DVT/PE™ Study

BACKGROUND

The safety and efficacy of nonvitamin K antagonist oral anticoagulants (NOACs) for the treatment of venous thromboembolism (VTE) have been established in randomized controlled trials, but limited data are available on their use in clinical practice across geographical regions.

METHODS

In the international RE-COVERY DVT/PE observational study (enrollment January 2016 to May 2017), we sought to characterize the patient population and describe the prescribed anticoagulant. Patient characteristics and anticoagulants administered after objective diagnosis of VTE were recorded at the baseline visit and again at hospital discharge or at 14 days after the diagnosis, whichever was later.

RESULTS

A total of 6095 patients were included, 50.2% were male, and the mean age was 61.5 years. The most common comorbidities were hypertension (35%), diabetes mellitus (11%), cancer (11%), prior VTE(11%), and trauma/surgery (7%). Overall, 77% of patients received oral anticoagulants, with 54% on NOACs and 23% on vitamin K antagonists (VKAs); 20% received parenteral anticoagulation only. NOACs comprised about 60% of anticoagulant treatment in Europe and Asia but substantially less in Latin America (29%) and the Middle East (21%). For NOAC therapies, the distribution (as a percentage of the total cohort) was rivaroxaban 25.6%, dabigatran 15.5%, apixaban 11.3%, and edoxaban 1.7%. Treatment with NOACs was less frequent in patients who had cancer, chronic renal disease, heart failure, or stroke.

CONCLUSIONS

These findings enhance our understanding of baseline characteristics and the initial management of patients with VTE in routine practice.

Design and rationale of the non-interventional, edoxaban treatment in routiNe clinical prActice in patients with venous ThromboEmbolism in Europe (ETNA-VTE-Europe) study

Background

Venous thromboembolism (VTE, including deep vein thrombosis [DVT] and pulmonary embolism [PE]) has an annual incidence rate of 104–183 per 100,000 person-years. After a VTE episode, the two-year recurrence rate is about 17%. Consequently, effective and safe anticoagulation is paramount. Edoxaban is a direct oral anticoagulant (DOAC) approved VTE treatment. Current safety and efficacy data are derived from clinical trials, and information about treatment durations beyond 12 months are not available.

Methods

ETNA-VTE-Europe is an 18-month prospective, single-arm, non-interventional, multinational post-authorisation safety study. Approximately 310 sites across eight European countries (Austria, Belgium, Germany, Ireland, Italy, the Netherlands, Switzerland and the United Kingdom) will participate in the study, with the intention to represent the regional distributions of centres, healthcare settings and specialties. An estimated cohort of 2700 patients will be recruited, the only enrolment criteria being acute symptomatic VTE, no participation in an interventional study, and treating physician decision to prescribe edoxaban independently from the registry. Data from patient medical records and/or telephone interviews will be collected at baseline, 1, 3, 6, 12 and 18 months. The primary objective is to evaluate the 18-month rate of symptomatic VTE recurrence in patients with VTE treated with edoxaban outside a clinical trial. The co-primary objective is to evaluate the real-world rates of bleeding and adverse drug reactions. Secondary outcomes include rates of other patient-relevant safety events, adherence to and discontinuation of edoxaban. Furthermore, 12-month ETNA-VTE-Europe data will be considered in the context of those for patients receiving different anticoagulants in the PREFER in VTE registry and Hokusai-VTE clinical trial.

Conclusions

ETNA-VTE-Europe will allow the safety and effectiveness of edoxaban to be evaluated over an extended period in acute symptomatic VTE patients encountered in routine clinical practice. Findings will be informative for European practitioners prescribing edoxaban as part of real-world VTE treatment/prevention.

Trial registration

ClinicalTrials.gov Identifier: NCT02943993.

How I treat recurrent venous thromboembolism in patients receiving anticoagulant therapy

Oral anticoagulant therapy for venous thromboembolism is very effective. When oral anticoagulants are managed well, the risk of recurrence is approximately 2 per 100 patient-years. The main reasons for a breakthrough event are underlying disease and subtherapeutic drug levels. The most common underlying disease that results in recurrence on treatment is cancer. Subtherapeutic drug levels can be caused by poor adherence to the drug regimen, interactions with other drugs or food, or inappropriate dosing. It is important to investigate and understand the cause whenever such an event occurs and to improve management of anticoagulants thereby avoiding further recurrences. Here we present 4 illustrative cases together with a discussion of the underlying pathology. Whereas the mechanisms are usually quite well understood, the management of further anticoagulation after a breakthrough event is based on minimal or no clinical trial evidence.

NOACs for treatment of venous thromboembolism in clinical practice

Randomised controlled trials have provided important information on the efficacy and safety of the non-vitamin K antagonist oral anticoagulants (NOACs) for treatment of venous thromboembolism (VTE), leading to registration and increasing use in clinical practice. Many questions remain to be answered, and observational studies are often more suitable for answering "real-world" questions than randomised controlled trials. Patient satisfaction, quality of life, and adherence and persistence in clinical practice with the drug regimen can only be assessed with an open-label design. Evaluation of risk for long-term sequelae of the disease requires much longer follow-up than is possible in registration trials. Treatment patterns and utilisation of health care resources can be assessed from observations in the clinical practice setting. We will review published as well as currently active observational studies with NOACs in VTE, with or without a comparator anticoagulant. These studies are based on cohorts of different sizes, registries, or administrative health care databases. We will also discuss some limitations in analysis and interpretation of observational studies.