Impact of oral anticoagulant choice for the secondary prevention of venous thromboembolism on the risk of inpatient bleeding

Basics of diagnosis and treatment of venous thromboembolism

Venous thromboembolism (VTE), comprising deep vein thrombosis and pulmonary embolism (PE), is common and associated with significant morbidity and mortality. The symptoms and signs of VTE are nonspecific. Well-established integrated diagnostic strategies combining clinical probability scores and D-dimer are used to identify patients with a low probability of VTE, where the diagnosis can be safely excluded without imaging. In patients with confirmed VTE, anticoagulation is the mainstay of treatment. However, patients with high-risk features at presentation may benefit from advanced reperfusion therapies such as thrombolysis and/or interventional approaches to reduce early mortality and/or long-term morbidity. The advent of direct oral anticoagulants has greatly simplified the treatment of VTE for most patients, with a persisting role for low molecular weight heparin and vitamin K antagonists in select patient groups. Following an initial 3 to 6 months of anticoagulation, those with major transient provoking factors can safely discontinue anticoagulation. Balancing the risk of recurrent VTE and bleeding risk is central to decisions regarding long-term anticoagulation, and patients should be included in shared decision-making. Assessment and recognition of common long-term complications such as postthrombotic syndrome and post-PE syndrome are also essential, given they are associated with significant adverse impact on long-term quality of life, with a significant risk of mortality associated with the less frequent complication of chronic thromboembolic pulmonary hypertension. This review provides a basic overview and framework for the diagnostic approach to deep vein thrombosis and PE, risk stratification of confirmed diagnoses, and management.

Association of anticoagulant choice with death in the primary treatment of noncancer venous thromboembolism: Medicare 2011-2018

Direct oral anticoagulants (DOACs; namely, rivaroxaban and apixaban) and warfarin are approved for venous thromboembolism (VTE) treatment. Few direct comparisons exist of DOACs on risk of death among patients with VTE, and for patients with concomitant conditions (eg, kidney disease, liver disease), clinical guidelines are unclear. We evaluated 6-month all-cause mortality by anticoagulant prescribed for primary treatment of VTE. Using data from a 20% sample of Medicare beneficiaries, we created a propensity score-matched analytic data set of 47 860 beneficiaries with noncancer incident VTE. We used Cox regression to estimate adjusted hazard ratios (HRs) of OACs with 6-month mortality, and tested interactions by liver and kidney disease. There were 3422 deaths over 6 months of follow-up. In adjusted models, patients prescribed rivaroxaban (HR = 0.82; 95% CI, 0.76-0.90) had lower mortality rates than those prescribed warfarin. There was no association when comparing apixaban with warfarin (HR = 0.96; 95% CI, 0.87-1.07). In head-to-head comparisons of apixaban and rivaroxaban, the HR was 1.14 (95% CI, 1.01-1.28). Findings were similar among patients with liver and kidney disease. Overall, risk of death was similar by OAC prescribed. Though it is possible residual confounding remained, there was some suggestion of lower risk with rivaroxaban than warfarin. Treatment with DOACs appears safe among patients with VTE who have concomitant kidney or liver disease. This article is part of a Special Collection on Pharmacoepidemiology.

Epidemiology and prevention of venous thromboembolism

Venous thromboembolism, that consists of the interrelated conditions deep-vein thrombosis and pulmonary embolism, is an under-appreciated vascular disease. In Western regions, approximately 1 in 12 individuals will be diagnosed with venous thromboembolism in their lifetime. Rates of venous thromboembolism are lower in Asia, but data from other regions are sparse. Numerous risk factors for venous thromboembolism have been identified, which can be classified as acute or subacute triggers (provoking factors that increase the risk of venous thromboembolism) and basal or acquired risk factors (which can be modifiable or static). Approximately 20% of individuals who have a venous thromboembolism event die within 1 year (although often from the provoking condition), and complications are common among survivors. Fortunately, opportunities exist for primordial prevention (prevention of the development of underlying risk factors), primary prevention (management of risk factors among individuals at high risk of the condition) and secondary prevention (prevention of recurrent events) of venous thromboembolism. In this Review, we describe the epidemiology of venous thromboembolism, including the incidence, risk factors, outcomes and opportunities for prevention. Meaningful health disparities exist in both the incidence and outcomes of venous thromboembolism. We also discuss these disparities as well as opportunities to reduce them.

Direct Oral Anticoagulants in Obese Patients with Venous Thromboembolism: Results of an Expert Consensus Panel

In clinical practice, direct oral anticoagulants (DOACs) are increasingly used for venous thromboembolism treatment and prevention. A substantial proportion of patients with venous thromboembolism are also obese. International guidance published in 2016 stated that DOACs could be used in standard doses in patients with obesity up to a body mass index [BMI] of 40 kg/m², but should not be used in those with severe obesity (BMI > 40 kg/m²) owing to limited supporting data at the time. Although updated guidance in 2021 removed this limitation, some healthcare providers still avoid DOACs even in patients with lower levels of obesity. Furthermore, there are still evidence gaps regarding treatment of severe obesity, the role of peak and trough DOAC levels in these patients, use of DOACs after bariatric surgery, and appropriateness of DOAC dose reduction in the setting of secondary venous thromboembolism prevention. This document describes proceedings and outcomes of a multidisciplinary panel convened to review these and other key issues regarding DOAC use for treatment or prevention of venous thromboembolism in individuals with obesity.