Treatment patterns and outcomes among hospitalized patients with venous thromboembolism in the United States: an analysis of electronic health records data

Delayed anticoagulation in venous thromboembolism: Reasons and associated outcomes

OBJECTIVE

We assessed the number of cases with delayed anticoagulation initiation, explored the reasons for the delay, and its impact on outcome in patients with acute venous thromboembolism (VTE) treated in an organized setting of treatment initiation and continuous, prospective follow-up.

METHODS

Patients with anticoagulation initiation delay >24 hours were identified within the cohort of patients with acute VTE enrolled in the Mayo Clinic Venous Thromboembolism Registry between 2013 and 2020. The reasons for treatment delay were explored by reviewing the electronic database. VTE recurrence, all-cause mortality, major bleeding, and clinically relevant nonmajor bleeding (CRNMB) were compared to those with no anticoagulation delay.

RESULTS

Of 2378 patients with acute VTE, 100 (4.2%) experienced an anticoagulation delay. We identified seven reasons for treatment delays: deferring anticoagulation initiation to specialists (n = 38), thrombocytopenia (n = 10), planned or recent procedure (n = 16), active or recent bleeding (n = 12), missed diagnosis (n = 7), logistics (n = 6), and patient decision (n = 4). In seven cases, no reason was identified. We identified modifiable reasons for anticoagulation delay in 55%. At 90-day follow-up, patients with anticoagulation delay had a higher rate of mortality and major bleeding. VTE recurrence and CRNMB were not statistically different compared to those without anticoagulation delay. After adjustment for age, weight, and cancer, hazard ratios (HRs) for VTE recurrence and major bleeding remained elevated but not to a statistically significant level.

CONCLUSION

In the setting of a highly organized system of anticoagulation initiation, the incidence of treatment delay is low. Yet most delays could be avoided. A low number of cases provide insufficient power to evaluate the clinical consequences of anticoagulation initiation delay; however, elevated HR for VTE recurrence and major bleeding suggest association and need for further investigation.

Clinical characteristics and treatment patterns of patients with venous thromboembolism (VTE) transitioning from hospital to post-discharge settings

OBJECTIVE

This study examined anticoagulant use during and after a hospital encounter for venous thromboembolism (VTE), a transition of care largely uncharacterized in the literature.

METHODS

Adults with a VTE diagnosis code during a hospital encounter (emergency department [ED], observation area [OBS], or inpatient hospital [IP]) from January 2012 to August 2017 were identified in an electronic health records database. The first such hospital encounter was defined as the index VTE encounter. Patients were linked to a claims database and required to be continuously enrolled for six months before the index admission date through six months after the index discharge date. Anticoagulants administered during the index VTE encounter and filled on or within 30 days of discharge were summarized descriptively overall, and by the type of index VTE encounter (IP, No IP) and anticoagulants administered during the index VTE encounter.

RESULTS

Among 2,968 eligible patients, mean (SD) age was 64 (16) years, 51% were female, 67% had an IP index VTE encounter, and 77% received anticoagulation therapy during the index VTE encounter. In total, 60% filled a prescription order for anticoagulant within 30 days post-discharge. Of those who received a direct oral anticoagulant (DOAC), warfarin, or parenteral anticoagulant only during the index VTE encounter, 74%, 69%, and 34%, respectively, filled a prescription for the same anticoagulant post-discharge. Patients treated with a DOAC or warfarin during an ED or OBS VTE encounter without a subsequent inpatient hospitalization were more likely to remain on the same anticoagulation therapy post-discharge than those with an inpatient hospitalization (81% vs 69% for DOAC and 75% vs 68% for warfarin).

CONCLUSIONS

Many patients treated with anticoagulation therapy during a VTE hospital encounter did not fill a prescription for an anticoagulant within 30 days post-discharge, highlighting an opportunity for improved management of care transitions in this patient population.

Predictors of Not Initiating Anticoagulation After Incident Venous Thromboembolism: A Danish Nationwide Cohort Study

PURPOSE

The purpose of this study was to investigate potential predictors associated with not initiating anticoagulation after incident venous thromboembolism.

METHODS

We linked Danish nationwide health registries to identify all patients with incident venous thromboembolism from 2003 through 2016. We defined treatment noninitiation as not claiming a prescription for an anticoagulant drug within 30 days after hospital discharge. To identify potential predictors of noninitiation, relative risks (RRs) with 95% confidence intervals (CIs) were calculated adjusting for other compliance-related factors.

RESULTS

The study included 38,044 patients with incident venous thromboembolism (53.2% female and median age 66.1 years). Of these, 24.1% (n = 9294) were noninitiators. Demographic and condition-related factors that predicted noninitiation included: female sex (RR 1.30; 95% CI, 1.25-1.34), age <30 vs age >65 years (RR 1.18; 95% CI, 1.13-1.33), hospitalization 0-3 days vs >3 days (RR 1.96; 95% CI, 1.87-2.07), incident deep venous thrombosis (RR 1.91; 95% CI, 1.81-2.01), and unprovoked venous thromboembolism (RR 1.13; 95% CI, 1.08-1.17). Socioeconomic factors had less influence on risk of noninitiation. Individual chronic diseases predictive of noninitiation included congestive heart failure (RR 1.27; 95% CI, 1.17-1.37), ischemic heart disease (RR 1.20; 95% CI, 1.13-1.28), and liver disease (RR 1.60; 95% CI, 1.42-1.81).

CONCLUSION

Up to one-fourth of patients diagnosed with incident venous thromboembolism did not initiate anticoagulant treatment within 30 days after hospital discharge. Identification of clinical predictors of noninitiation may enable implementation of patient-tailored strategies to improve adherence and thereby potentially prevent venous thromboembolism morbidity, mortality, and recurrence.

Treatment and Outcomes of Acute Pulmonary Embolism and Deep Venous Thrombosis: The CVRN VTE Study

BACKGROUND

Few studies describe both inpatient and outpatient treatment and outcomes of patients with acute venous thromboembolism in the United States.

METHODS

A multi-institutional cohort of patients diagnosed with confirmed pulmonary embolism or deep venous thrombosis during the years 2004 through 2010 was established from 4 large, US-based integrated health care delivery systems. Computerized databases were accessed and medical records reviewed to collect information on patient demographics, clinical risk factors, initial antithrombotic treatment, and vital status. Multivariable Cox regression models were used to estimate the risk of death at 90 days.

RESULTS

The cohort comprised 5497 adults with acute venous thromboembolism. Pulmonary embolism was predominantly managed in the hospital setting (95.0%), while 54.5% of patients with lower extremity thrombosis were treated as outpatients. Anticoagulant treatment differed according to thromboembolism type: 2688 patients (92.8%) with pulmonary embolism and 1625 patients (86.9%) with lower extremity thrombosis were discharged on anticoagulants, compared with 286 patients (80.1%) with upper extremity thrombosis and 69 (54.8%) patients with other thrombosis. While 4.5% of patients died during the index episode, 15.4% died within 90 days. Pulmonary embolism was associated with a higher 90-day death risk than lower extremity thrombosis (adjusted hazard ratio 1.23; 95% confidence interval, 1.04-1.47), as was not being discharged on anticoagulants (adjusted hazard ratio 5.56; 95% confidence interval, 4.76-6.67).

CONCLUSIONS

In this multicenter, community-based study of patients with acute venous thromboembolism, anticoagulant treatment and outcomes varied by thromboembolism type. Although case fatality during the acute episode was relatively low, 15.4% of people with thromboembolism died within 90 days of the index diagnosis.

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.