Warfarin Discontinuation in Patients With Unprovoked Venous Thromboembolism: A Large US Insurance Database Analysis

Systematic literature review of treatment patterns for venous thromboembolism patients during transitions from inpatient to post-discharge settings

Introduction

Direct oral anticoagulants (DOACs) have emerged as viable alternatives to traditional treatments such as vitamin K antagonists (VKAs) for venous thromboembolism (VTE). The objective of this review was to summarize evidence on the use of DOACs and VKAs to treat VTE in the US for patients transitioning from inpatient to post-discharge settings.

Materials and methods

A systematic review of the VTE literature identified studies published in English (January 1, 2011–December 31, 2016) that reported inpatient and post-discharge treatments and discharge location. Two reviewers screened abstracts, abstracted information from included studies, and assessed the quality of the study methodology and reporting.

Results

Forty-nine studies were included (24 clinical and 25 economic). A limited number of studies (eight clinical and three economic) examined VTE treatment patterns during transitions of care from inpatient to post-discharge settings, irrespective of anticoagulant (eg, DOAC, warfarin, heparin), and < 25% of all studies reported a post-discharge location. Three clinical studies that reported inpatient and outpatient treatment found better patient outcomes with DOAC vs warfarin. Fourteen economic studies reported that DOACs were associated with shorter hospital length of stay (LOS) and lower direct costs vs warfarin. No studies reported indirect costs.

Discussion

Although DOACs are associated with shorter LOS, lower costs, and better patient outcomes vs VKAs, it appears in one study that only a small percentage of patients with stable VTE who are discharged to home may be receiving DOACs.

Conclusion

These findings identified the potential areas of opportunity to improve the management of VTE through coordination of care from the inpatient to the outpatient settings.

Limited evidence on persistence with anticoagulants, and its effect on the risk of recurrence of venous thromboembolism: a systematic review of observational studies

PURPOSE

The risk of venous thromboembolism (VTE) recurrence is high following an initial VTE event, and it persists over time. This recurrence risk decreases rapidly after starting with anticoagulation treatment and reduces by ~80%-90% with prolonged anticoagulation. Nonpersistence with anticoagulants could lead to increased risk of VTE recurrence. This systematic review aimed to estimate persistence at 3, 6, and 12 months with anticoagulants in patients with VTE, and to evaluate the risk of VTE recurrence in nonpersistent patients.

METHODS

PubMed and Embase(®) were searched up to May 3, 2014 and the search results updated to May 31, 2015. Studies involving patients with VTE aged ≥18 years, treatment with anticoagulants intended for at least 3 months or more, and reporting data for persistence were included. Proportions were transformed using Freeman-Tukey double arcsine transformation and pooled using the DerSimonian-Laird random-effects approach.

RESULTS

In total, 12 observational studies (7/12 conference abstracts) were included in the review. All 12 studies either reported or provided data for persistence. The total number of patients meta-analyzed to estimate persistence at 3, 6, and 12 months was 71,969 patients, 58,940 patients, and 68,235 patients, respectively. The estimated persistence for 3, 6, and 12 months of therapy was 83% (95% confidence interval [CI], 78-87; I (2)=99.3%), 62% (95% CI, 58-66; I (2)=98.1%), and 31% (95% CI, 22-40; I (2)=99.8%), respectively. Only two studies reported the risk of VTE recurrence based on nonpersistence - one at 3 months and the other at 12 months.

CONCLUSION

Limited evidence showed that persistence was suboptimal with an estimated 17% patients being nonpersistent with anticoagulants in the crucial first 3 months. Persistence declined over 6 and 12 months. Observational data on persistence with anticoagulation treatment, especially direct oral anticoagulants, in patients with VTE and its effect on risk of VTE recurrence were scarce and further research is required.