Clinical and economic aspects of managing venous thromboembolism in the outpatient setting

Low-Molecular-Weight Heparin Versus Warfarin in Adult Cancer Patients as a Precision Medicine for Thrombosis: A Systematic Review and Meta-Analysis

Venous thromboembolism (VTE) is a condition often seen in patients diagnosed with cancer and is recognized as a predictor of poor outcomes in these patients. The probability of VTE recurring is generally higher in people with cancer than in those without; hence, addressing this issue is essential when making healthcare decisions. Therefore, our systematic review was primarily designed to compare low-weight- molecular heparin (LMWH) to warfarin in reducing recurrent VTE among cancer patients. However, other outcomes were also evaluated, such as mortality and bleeding events observed more in cancer patients. The selection of relevant articles was carried out using a database search and a manual search, which involved reviewing reference lists of articles eligible for inclusion in the current review. The methodological quality of each included study was then assessed using Cochrane's risk of bias tool in the Review Manager software (RevMan 5.4.1). Additionally, pooled results were examined using the Review Manager software and presented as forest plots. Our search of electronic databases elicited a total of 2163 articles, of which only six were deemed eligible for inclusion and analysis. Data pooled from the six studies demonstrated the effectiveness of LMWH in minimizing the reoccurrence of VTE over warfarin [risk ratio (RR): 0.67; 95% CI: 0.47 - 0.95; p = 0.03]. However, LMWH had a similar effect statistically as warfarin on the major bleeding events (RR: 1.05; 95% CI: 0.62 - 1.77; p = 0.85), minor bleeding events (RR: 0.80; 95% CI: 0.54 - 1.20; p = 0.28), and all-cause mortality (RR: 1.00; 95% CI: 0.88 - 1.13; p = 0.99). While LMWH demonstrated its effectiveness in minimizing the incidence of VTE recurrence over warfarin in cancer patients, it had no statistical difference in terms of mortality or bleeding events when compared to warfarin. Based on our findings, we recommend that LMWH continues to be used as a first-line treatment regimen to mitigate recurrent VTE in cancer patients.

Outpatient Management in Patients with Venous Thromboembolism with Edoxaban: A Post Hoc Analysis of the Hokusai-VTE Study

Direct oral anticoagulants (DOACs) facilitate the outpatient treatment of venous thromboembolism (VTE). However, the pivotal trials of DOACs have not reported outcomes separately for patients managed either as outpatients or in the hospital. We performed a subgroup analysis of the Hokusai-VTE study comparing efficacy and safety of edoxaban with warfarin in 8,292 patients with acute VTE. Patients received initial therapy with open-label enoxaparin or unfractionated heparin for ≥5 days in the hospital or as an outpatient at the discretion of the treating physician. Edoxaban or warfarin was then given for 3 to 12 months. The primary efficacy outcome was the cumulative incidence of symptomatic recurrent VTE at 12 months. The principal safety outcome was the incidence of clinically relevant bleeding (composite of major or clinically relevant non-major bleeding). Of the 5,223 consecutively enrolled patients with recorded hospital status and length of stay, 1,414 patients (27.1%) were managed as outpatients and 3,809 were managed in hospital. Among the outpatients, initial presentation was symptomatic deep-vein thrombosis (DVT) in 1,183 patients (83.7%) and pulmonary embolism (PE) in 231 patients (16.3%). Among the outpatients with DVT, recurrent VTE occurred in 18 (3.0%) given edoxaban and in 21 (3.6%) given warfarin (risk difference: −0.61, 95% confidence interval [CI]: −2.6 to 1.4). The principal safety outcome in outpatients occurred in 46 edoxaban patients (7.7%) and in 48 warfarin patients (8.3%; risk difference: −0.59, 95% CI: −3.7 to 2.5). Most outpatients had symptomatic DVT at presentation. In these patients, initial heparin followed by edoxaban had similar efficacy and safety to standard therapy with heparin and warfarin.

Cancer-related venous thromboembolic disease: current management and areas of uncertainty

The relationship between cancer and venothromboembolic events is a complex, multifactorial process which is still not fully understood and therefore the use of current generic guidelines may be inadequate. Current management of cancer-related VTE may be suboptimal because of the lack of cancer-specific studies into the role of primary prophylaxis in both ambulant and non-ambulant cancer patients. Further research into developing cancer-specific risk assessment tools and the choice, dose and duration of prophylaxis is required. The management of confirmed symptomatic VTE in cancer patients is outlined but certain controversies remain. Areas for further research include the management of asymptomatic unsuspected VTE events, recurrent VTE events on treatment and the role of IVC filters and other treatment options are required. This paper attempts to cover some of the recent developments and areas of uncertainty surrounding the management of cancer-related VTE.

Outpatient management of stable acute pulmonary embolism: proposed accelerated pathway for risk stratification

Pulmonary embolism (PE) is a major health problem and a cause of worldwide morbidity and mortality. The current standard therapy for acute PE encourages admitting patients to the hospital for administration of parenteral anticoagulation therapy as a bridge to oral vitamin K antagonists. Prognostic models that identify patients with stable (nonmassive) acute PE (SPE) who are at low risk for adverse outcome have recently been reported. Based on these risk stratification models, hospital-based therapy is warranted for patients with PE who meet the criteria associated with a high risk for adverse outcome. However, a growing body of evidence suggests the feasibility of partial outpatient management and accelerated hospital discharge (AHD) in a subset of patients with SPE. Prospective validation of these risk stratification models for predicting patient suitability for AHD is needed.

Management patterns of thrombosis prophylaxis and related costs in hip and knee replacement in Germany

The objective of the study was to depict treatment strategies, health care utilisation and cost evaluation of hip and knee replacement surgery in Germany, with a particular emphasis on thrombosis prophylaxis (TP) for the prevention of deep vein thrombosis (DVT). In this multi-centre prospective cohort study, medical record data (socio-demographics, risk factors for thrombosis, thrombosis prophylaxis, course of hospital stay) were collected for patients undergoing either total hip replacement (THR) or total knee replacement (TKR). One and three months post-operatively, post-operative outcomes and health care resource use were documented by patient and physician questionnaires. A total of 309 patients participated in the study (59% female, mean age 66 [SD 10] years). Parenteral anticoagulation was administered for a mean of 38 (SD 16) days. 27 (9%) patients received subsequent oral anticoagulation for a mean of 38 (SD 21) additional days. Symptomatic DVT was reported by four (1.3%) patients. Mean overall direct costs associated with surgery from baseline to 3 months were EUR 11 264 (median 11 564, SD 2 481). Hospital and rehabilitation accounted for 97% of direct costs; costs for medications, physical therapy, physician office visits, out-of-pocket expenses, as well as complication costs accounted for an additional 3% of direct costs. Within these direct costs, a mean of EUR 348 (SD 361) was related to thrombosis prophylaxis, accounting for 3% of direct costs. Mean overall cost was EUR 11 926 (SD 2 481), including 6% indirect costs of productivity loss. Extended thrombosis prophylaxis was observed in the usual care setting of the study and associated with low incidence of symptomatic DVT. Thrombosis prophylaxis is — within the considerable economic burden of joint replacement surgery — a relatively small cost component.

Anticoagulants in the treatment of deep vein thrombosis

Intravenous (IV) infusion of unfractionated heparin (UFH) followed by oral administration of warfarin remains the cornerstone of clinical treatment of deep vein thrombosis (DVT). Results from numerous clinical trials demonstrate that subcutaneously administered low-molecular-weight heparin (LMWH) is at least as effective and as safe as IV UFH. Treatment with LMWH has several clinical advantages over treatment with UFH, including less-frequent dosing and elimination of the need for monitoring. The introduction of LMWHs has made it possible for physicians to offer outpatient treatment of DVT, with the associated advantage of reduced costs due to shortened hospital stays. However, the optimal duration of anticoagulant therapy after DVT is still debated, as it depends on an individual patient's potential risk for recurrence or treatment-associated complications. Patients are usually risk stratified on the basis of multiple clinical characteristics, including the location of thromboemboli, the presence or absence of cancer, the assumed etiology or cause of DVT (idiopathic vs. due to a transient risk factor), and the presence of certain thrombophilic conditions. High-risk patients often receive inpatient treatment with UFH or LMWH and are candidates for long-term (> or = 6 months) oral anticoagulation, whereas short-term anticoagulation (3 to 6 months) is usually indicated for patients who are at lower risk of recurrence or therapeutic complications and who can be treated with LMWH on an outpatient basis. The introduction of LMWHs has resulted in significant clinical progress for the treatment of DVT.

Warfarin versus low-molecular-weight heparin therapy in cancer patients

The association between cancer and venous thromboembolism (VTE) is well established. Importantly, VTE is a significant cause of mortality in cancer patients. Although long-term warfarin (Coumadin(trade mark); Bristol-Myers Squibb; New York, NY) therapy is the mainstay of treatment for cancer patients with VTE, there are many practical problems with its use in this population. In particular, achieving therapeutic drug levels is difficult in cancer patients due to the increased risk of drug interactions, malnutrition, vomiting, and liver dysfunction in these patients. Moreover, cancer patients are at an increased risk of adverse effects of warfarin therapy. In contrast, low-molecular-weight heparins (LMWHs) are associated with a lower risk of adverse events compared with warfarin in patients with cancer. These agents also offer practical advantages compared with warfarin, including more predictable anticoagulant effects and ease of administration in addition to possible antineoplastic effects. Several LMWHs have demonstrated superior efficacy to warfarin in the secondary prevention of VTE. In particular, the LMWH, dalteparin (Fragmin; Pfizer; New York, NY), has recently been shown to have superior efficacy to warfarin in a large trial of patients with cancer and VTE without increasing the risk of bleeding. A randomized trial of dalteparin has also shown improved response rates and survival in patients with small cell lung cancer. In view of the availability of more effective and reliable alternatives to warfarin therapy in cancer patients, it is appropriate to reassess the role of warfarin therapy in patients with cancer and VTE. Further evaluation of the LMWHs for effects on cancer outcome is indicated.