Cost of venous thromboembolism in hospitalized medically ill patients

Extended Venous Thromboembolism Prophylaxis in Medically Ill Patients: An NATF Anticoagulation Action Initiative

Hospitalized patients with acute medical illnesses are at risk for venous thromboembolism (VTE) during and after a hospital stay. Risk factors include physical immobilization and underlying pathophysiologic processes that activate the coagulation pathway and are still present after discharge. Strategies for optimal pharmacologic VTE thromboprophylaxis are evolving, and recommendations for VTE prophylaxis can be further refined to protect high-risk patients after hospital discharge. An early study of extended VTE prophylaxis with a parenteral agent in medically ill patients yielded inconclusive results with regard to efficacy and bleeding. In the Acute Medically Ill VTE Prevention with Extended Duration Betrixaban (APEX) trial, extended use of betrixaban halved symptomatic VTE, decreased hospital readmission, and reduced stroke and major adverse cardiovascular events compared with standard enoxaparin prophylaxis. Based on findings from APEX, the Food and Drug Administration approved betrixaban in 2017 for extended VTE prophylaxis in acute medically ill patients. In the Reducing Post-Discharge Venous Thrombo-Embolism Risk (MARINER) study, extended use of rivaroxaban halved symptomatic VTE in high-risk medical patients compared with placebo. In 2019, rivaroxaban was approved for extended thromboprophylaxis in high-risk medical patients, thus making available a new strategy for in-hospital and post-discharge VTE prevention. To address the critical unmet need for VTE prophylaxis in medically ill patients at the time of hospital discharge, the North American Thrombosis Forum (NATF) is launching the Anticoagulation Action Initiative, a comprehensive consensus document that provides practical guidance and straightforward, patient-centered recommendations for VTE prevention during hospitalization and after discharge.

Effectiveness and safety of betrixaban extended prophylaxis for venous thromboembolism compared with standard-duration prophylaxis intervention in acute medically ill patients: a systematic literature review and network meta-analysis

Aims: To determine the clinical effectiveness and safety of venous thromboembolism (VTE) prophylaxis using US- and Europe-approved anticoagulants relative to extended-duration VTE prophylaxis with betrixaban. Low molecular weight heparins (LMWHs), unfractionated heparin (UFH), fondaparinux sodium and placebo were each compared to betrixaban, as standard-duration VTE prophylaxis for hospitalized, non-surgical patients with acute medical illness at risk of VTE. Materials and methods: A systematic literature review was conducted up to June 2019 to identify randomized controlled trials (RCTs) of VTE prophylaxis in hospitalized, non-surgical patients with acute medical illness at risk of VTE. Studies that reported the occurrence of VTE events (including death) and, where possible, major bleeding, from treatment initiation to 20-50 days thereafter were retrieved and extracted. A Bayesian fixed effect network meta-analysis was used to estimate efficacy and safety of betrixaban compared with standard-duration VTE prophylaxis. Results: Seven RCTs were analyzed which compared betrixaban, LMWHs, UFH, fondaparinux sodium, or placebo. There were significantly higher odds (median odds [95% credible interval]) of VTE with LMWHs (1.38 [1.12-1.70]), UFH (1.60 [1.05-2.46]), and placebo (2.37 [1.55-3.66]) compared with betrixaban. There were significantly higher odds of VTE-related death with placebo (7.76 [2.14-34.40]) compared with betrixaban. No significant differences were observed for the odds of major bleeding with all comparators, VTE-related death with any active standard-duration VTE prophylaxis, or of VTE with fondaparinux sodium, compared with betrixaban. Limitations and conclusions: In this indirect comparison, betrixaban was shown to be an effective regimen with relative benefits compared with LMWHs and UFH. This indicates that betrixaban could reduce the burden of VTE in at-risk hospitalized patients with acute medical illness who need extended prophylaxis, though without direct comparative evidence, stronger conclusions cannot be drawn.

Cost-Effectiveness of Betrixaban Compared with Enoxaparin for Venous Thromboembolism Prophylaxis in Nonsurgical Patients with Acute Medical Illness in the United States

BACKGROUND

Studies show that the risk of venous thromboembolism (VTE) continues post-discharge in nonsurgical patients with acute medical illness. Betrixaban is the first anticoagulant approved in the United States (US) for VTE prophylaxis extending beyond hospitalization.

OBJECTIVE

The aim was to establish whether betrixaban for VTE prophylaxis in nonsurgical patients with acute medical illness at risk of VTE in the US is cost-effective compared with enoxaparin.

METHODS

A cost-effectiveness analysis was conducted, estimating the cost per quality-adjusted life-year (QALY) gained with betrixaban (35-42 days) compared with enoxaparin (6-14 days) from a US payer perspective over a lifetime horizon. A decision tree (DT) estimated primary VTE events, thrombotic events, and treatment complications in the first 3 months based on data from the phase III Acute Medically Ill VTE Prevention with Extended Duration Betrixaban study. A Markov model estimated recurrent events and long-term complication risks from published literature. EuroQoL-5 Dimensions utility data and costs inflated to 2017 US dollars (US$) were from published literature. Results were discounted at 3.0% per annum. Deterministic and probabilistic sensitivity analyses explored uncertainty.

RESULTS

Betrixaban dominated enoxaparin, with savings of US$784 and increased QALYs of 0.017 per patient. In addition, betrixaban dominated enoxaparin across all sensitivity analyses, but was most sensitive to utilities and DT probabilities. Furthermore, probabilistic sensitivity analysis found that betrixaban was more cost-effective than enoxaparin at all willingness-to-pay thresholds.

CONCLUSION

Betrixaban can be considered cost-effective for nonsurgical patients with acute medical illness at risk of VTE, requiring longer VTE prophylaxis from hospitalization through post-discharge.

Automated Extraction of VTE Events From Narrative Radiology Reports in Electronic Health Records: A Validation Study

BACKGROUND

Surveillance of venous thromboembolisms (VTEs) is necessary for improving patient safety in acute care hospitals, but current detection methods are inaccurate and inefficient. With the growing availability of clinical narratives in an electronic format, automated surveillance using natural language processing (NLP) techniques may represent a better method.

OBJECTIVE

We assessed the accuracy of using symbolic NLP for identifying the 2 clinical manifestations of VTE, deep vein thrombosis (DVT) and pulmonary embolism (PE), from narrative radiology reports.

METHODS

A random sample of 4000 narrative reports was selected among imaging studies that could diagnose DVT or PE, and that were performed between 2008 and 2012 in a university health network of 5 adult-care hospitals in Montreal (Canada). The reports were coded by clinical experts to identify positive and negative cases of DVT and PE, which served as the reference standard. Using data from the largest hospital (n=2788), 2 symbolic NLP classifiers were trained; one for DVT, the other for PE. The accuracy of these classifiers was tested on data from the other 4 hospitals (n=1212).

RESULTS

On manual review, 663 DVT-positive and 272 PE-positive reports were identified. In the testing dataset, the DVT classifier achieved 94% sensitivity (95% CI, 88%-97%), 96% specificity (95% CI, 94%-97%), and 73% positive predictive value (95% CI, 65%-80%), whereas the PE classifier achieved 94% sensitivity (95% CI, 89%-97%), 96% specificity (95% CI, 95%-97%), and 80% positive predictive value (95% CI, 73%-85%).

CONCLUSIONS

Symbolic NLP can accurately identify VTEs from narrative radiology reports. This method could facilitate VTE surveillance and the evaluation of preventive measures.

Heart failure and risk of venous thromboembolism: a systematic review and meta-analysis

BACKGROUND

Venous thromboembolism is a major global health problem that is often secondary to other clinical situations. Many studies have investigated the association between venous thromboembolism and heart failure, but have yielded inconsistent findings. We aimed to quantify the absolute and relative risks (RR) for venous thromboembolism in patients with heart failure after hospital admission. We also assessed rates of venous thromboembolism in patients in different settings.

METHODS

In this systematic review and meta-analysis, we searched for studies investigating the risk of venous thromboembolism in patients in hospital with heart failure. We searched for studies published between Jan 1, 1955, and March 31, 2015, in PubMed, Embase, Evidence-Based Medicine Reviews, Allied and Complementary Medicine Database, Ovid HealthSTAR, Global Health, Ovid Nursing Database, Web of Science, CINAHL Plus, ProQuest Central, Conference Papers Index, BIOSIS Previews, and ClinicalTrials.gov. All cohort studies and subgroup analyses of randomised controlled trials (RCTs) were eligible for inclusion if they reported venous thromboembolism rates (number of events per follow-up period) or RR estimates. We extracted data from published reports and contacted the corresponding authors of records with insufficient quantitative data. RRs and 95% CIs were pooled using a random-effects model. This study is registered with PROSPERO, number CRD42014015504.

FINDINGS

Of 8673 records identified, we included 71 studies with data from 88 cohorts in our analysis, with 59 cohorts included in the assessment of venous thromboembolism rates and 46 cohorts included in the meta-analysis of heart failure and risk of venous thromboembolism. Venous thromboembolism rates varied widely in patients in hospital with heart failure from different settings. The overall median symptomatic venous thromboembolism rate was 2·48% (IQR 0·84-5·61); rates was were 3·73% (1·05-7·31) for patients who did not receive thromboprophylaxis and 1·47% (0·64-3·54) for those who did. Overall, patients with heart failure in hospital had an RR of 1·51 (1·36-1·68) for venous thromboembolism. The overall I(2) statistic was 96·1% and there was no evidence of publication bias (Egger's test, p=0·46).

INTERPRETATION

Heart failure is a common independent risk factor for venous thromboembolism. Thromoboprophylaxis should be considered in clinical practice for high-risk patients.

FUNDING

National Natural Science Foundation.

Venous Thromboembolism in Critically Ill Medical Patients Receiving Chemoprophylaxis

Purpose:

To compare the incidence of 90-day venous thromboembolism (VTE) in obese critically ill medical patients receiving VTE chemoprophylaxis with nonobese patients of similar illness severity. We also identified other VTE risk factors.

Methods:

Eligible patients spent ≥24 hours in an intensive care unit between November 2007 and November 2013 and received VTE chemoprophylaxis within 48 hours of admission. The primary outcome was 90-day VTE.

Results:

A total of 11 111 patients were evaluated, of which 1732 obese and 1831 nonobese patients were enrolled with mean BMIs of 38.9 ± 9.2 kg/m2 and 24.5 ± 3.1 kg/m2 and mean Acute Physiology and Chronic Health Evaluation II scores of 28.4 ± 11.8 and 26.6 ± 11.7, respectively. The rate of 90-day VTE for the total cohort, obese, and nonobese patients was 6.5%, 7.5%, and 5.5%, respectively. Obese patients were more likely to develop VTE compared with nonobese patients (odds ratio [OR]: 1.41; 95% confidence interval [CI]: 1.03 -1.93). Other risk factors significantly associated with 90-day VTE included prior VTE (OR: 3.93; 95% CI: 1.83-8.48), trauma with surgery in the previous 30 days (OR: 3.70; 95% CI: 1.39-9.86), central venous catheters (OR: 2.64; 95% CI: 1.87-3.72), surgery within 90 days (OR: 2.40; 95% CI: 1.61-3.58), mechanical ventilation (OR: 1.94; 95% CI: 1.39-2.71), male sex (OR: 1.55; 95% CI: 1.13-2.14), and increasing age using 1-year increments (OR: 1.02; 95% CI: 1.01 -1.03).

Conclusions:

The rate of VTE in critically ill medical patients remains high despite standard chemoprophylaxis. Obesity is among 8 risk factors independently associated with 90-day VTE.

Costs of Venous Thromboembolism, Catheter-Associated Urinary Tract Infection, and Pressure Ulcer

OBJECTIVE

To estimate differences in the length of stay (LOS) and costs for comparable pediatric patients with and without venous thromboembolism (VTE), catheter-associated urinary tract infection (CAUTI), and pressure ulcer (PU).

METHODS

We identified at-risk children 1 to 17 years old with inpatient discharges in the Nationwide Inpatient Sample. We used a high dimensional propensity score matching method to adjust for case-mix at the patient level then estimated differences in the LOS and costs for comparable pediatric patients with and without VTE, CAUTI, and PU.

RESULTS

Incidence rates were 32 (VTE), 130 (CAUTI), and 3 (PU) per 10 000 at-risk patient discharges. Patients with VTE had an increased 8.1 inpatient days (95% confidence interval [CI]: 3.9 to 12.3) and excess average costs of $27 686 (95% CI: $11 137 to $44 235) compared with matched controls. Patients with CAUTI had an increased 2.4 inpatient days (95% CI: 1.2 to 3.6) and excess average costs of $7200 (95% CI: $2224 to $12 176). No statistical differences were found between patients with and without PU.

CONCLUSIONS

The significantly extended LOS highlights the substantial morbidity associated with these potentially preventable events. Hospitals seeking to develop programs targeting VTE and CAUTI should consider the improved turnover of beds made available by each event prevented.

Aspirin Increases the Risk of Venous Thromboembolism in Surgical Patients

The risk of venous thromboembolism (VTE) for patients taking an antiplatelet agent is largely unknown. This study aimed to investigate the association between antiplatelet agent use before admission with the risk of in-hospital VTE in surgical intensive care unit (ICU) patients. A retrospective review of all patients admitted to the surgical ICU at a Level I trauma center over 30 months was performed. Patients who underwent diagnostic imaging for VTE were selected. Patients were divided based on whether or not antiplatelet agents were used before admission (APTA vs NAPTA). The primary outcome was VTE occurrence. A forward logistic regression model was used to identify factors independently associated with the primary outcome. During the study period, 461 (24%) patients met inclusion criteria: 70 (15%) APTA and 391 (85%) NAPTA. After adjusting for confounding factors, APTA patients were at a significantly higher risk for developing VTE (59 vs 40%; adjusted odds ratio, 1.8; 95% confidence interval, 1.0 to 3.0; adjusted P = 0.04). Whether or not antiplatelet agents were resumed during the hospital stay and the day on which they were resumed did not affect VTE risk. In conclusion, surgical ICU patients receiving antiplatelet agents before admission are at a significantly higher risk for development of VTE.

Clostridium difficile increases the risk for venous thromboembolism

BACKGROUND

Inflammatory bowel disease is associated with a higher risk for venous thromboembolism (VTE). Whether Clostridium difficile infection similarly increases this risk is unknown.

METHODS

This was a retrospective analysis of patients admitted to the surgical intensive care unit (ICU) at the Cedars-Sinai Medical Center from February 2011 to July 2013. The 2 groups were compared using standard statistical methodology.

RESULTS

During the 30-month study period, a total of 1,728 patients were admitted to the surgical ICU. A total of 64 patients (3.7%) tested positive for C. difficile. The use of chemical prophylaxis for VTE was significantly higher in the C. difficile group (64.1% vs 46.2%, P = .005). Nonetheless, C. difficile patients had a higher risk for development of a VTE (23.4% vs 11.0%, adjusted odds ratio [95% confidence interval]: 1.87 [1.01 to 3.48], P = .048). In a forward logistic regression model, C. difficile was found to be independently associated with the development of VTE (adjusted odds ratio [95% confidence interval]: 1.87 [1.00 to 3.47], P = .049).

CONCLUSIONS

C. difficile infection increases the risk for VTE in surgical patients admitted to the ICU.