Oral Anticoagulants for Nonvalvular Atrial Fibrillation in Patients With High Risk of Gastrointestinal Bleeding.

Importance: Many patients with nonvalvular atrial fibrillation (NVAF) are at a high risk of gastrointestinal (GI) bleeding due to conditions including older age; stage III to V chronic kidney disease (CKD); HAS-BLED (hypertension, kidney or liver disease, stroke history, prior bleeding, unstable international normalized ratio, age >65, drug or alcohol use) score of 3 or greater; corticosteroid, antiplatelet or nonsteroidal anti-inflammatory drug (NSAID) use; or GI conditions. Objective: To compare the risk of stroke and/or systemic embolism (SE) and major bleeding (MB) among patients with NVAF and high risk of GI bleeding who received non-vitamin K antagonist oral anticoagulants (NOACs) vs those who received warfarin. Design, Setting, and Participants: This retrospective cohort study included patients with NVAF who were 75 years and older; had stage III to V CKD; had an HAS-BLED score of 3 or greater; used corticosteroids, antiplatelets, or NSAIDs; or had GI conditions. Data were collected from the Centers for Medicare & Medicaid Services and 4 commercial insurance databases between January 1, 2012, and September 30, 2015. Data analysis was conducted from January 2012 to September 2015. Exposures: New prescription for apixaban, dabigatran, rivaroxaban, or warfarin between January 1, 2013, and September 30, 2015 (identification period). Main Outcomes and Measures: Six propensity score-matched cohorts were created to compare between study drugs. For the primary objective, Cox models were used to estimate stroke and/or SE and MB hazard ratios (HRs). Results: A total of 381 054 patients (187 489 [49.2%] women) with NVAF and at least 1 high-risk GI bleeding factor were identified (HAS-BLED score ≥3: 284 527 [74.7%]; aged ≥75 years: 252 835 [66.4%]; corticosteroid, antiplatelet, or NSAID therapy: 107 675 [28.3%]; prior GI bleeding conditions: 74 818 [19.6%]; and stage III-V CKD: 56 892 [14.9%]). All NOACs were associated with a lower risk of stroke and/or SE vs warfarin (apixaban: HR, 0.60; 95% CI, 0.52-0.68; dabigatran: HR, 0.75; 95% CI, 0.64-0.88; rivaroxaban: HR, 0.79; 95% CI, 0.73-0.86). Compared with warfarin, apixaban and dabigatran were associated with a lower risk of MB (apixaban: HR, 0.59; 95% CI, 0.56-0.63; dabigatran: HR, 0.78; 95% CI, 0.70-0.86), while rivaroxaban was associated with a higher risk (HR, 1.11; 95% CI, 1.05-1.16). Conclusions and Relevance: In this study of patients with NVAF and high risk of GI bleed, NOACs were associated with lower rates of stroke and/or SE, but NOACs had varying risks of MB compared with warfarin. These results may help inform treatment options in this patient population.

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 Oral Anticoagulants Among Nonvalvular Atrial Fibrillation Patients.

Background and Purpose- This ARISTOPHANES study (Anticoagulants for Reduction in Stroke: Observational Pooled Analysis on Health Outcomes and Experience of Patients) used multiple data sources to compare stroke/systemic embolism (SE) and major bleeding (MB) among a large number of nonvalvular atrial fibrillation patients on non-vitamin K antagonist oral anticoagulants (NOACs) or warfarin. Methods- A retrospective observational study of nonvalvular atrial fibrillation patients initiating apixaban, dabigatran, rivaroxaban, or warfarin from January 1, 2013, to September 30, 2015, was conducted pooling Centers for Medicare and Medicaid Services Medicare data and 4 US commercial claims databases. After 1:1 NOAC-warfarin and NOAC-NOAC propensity score matching in each database, the resulting patient records were pooled. Cox models were used to evaluate the risk of stroke/SE and MB across matched cohorts. Results- A total of 285 292 patients were included in the 6 matched cohorts: 57 929 apixaban-warfarin, 26 838 dabigatran-warfarin, 83 007 rivaroxaban-warfarin, 27 096 apixaban-dabigatran, 62 619 apixaban-rivaroxaban, and 27 538 dabigatran-rivaroxaban patient pairs. Apixaban (hazard ratio [HR], 0.61; 95% CI, 0.54-0.69), dabigatran (HR, 0.80; 95% CI, 0.68-0.94), and rivaroxaban (HR, 0.75; 95% CI, 0.69-0.82) were associated with lower rates of stroke/SE compared with warfarin. Apixaban (HR, 0.58; 95% CI, 0.54-0.62) and dabigatran (HR, 0.73; 95% CI, 0.66-0.81) had lower rates of MB, and rivaroxaban (HR, 1.07; 95% CI, 1.02-1.13) had a higher rate of MB compared with warfarin. Differences exist in rates of stroke/SE and MB across NOACs. Conclusions- In this largest observational study to date on NOACs and warfarin, the NOACs had lower rates of stroke/SE and variable comparative rates of MB versus warfarin. The findings from this study may help inform the discussion on benefit and risk in the shared decision-making process for stroke prevention between healthcare providers and nonvalvular atrial fibrillation patients. Clinical Trial Registration- URL: https://www.clinicaltrials.gov/ . Unique identifier: NCT03087487.

Comparison of effectiveness and safety of treatment with apixaban vs. other oral anticoagulants among elderly nonvalvular atrial fibrillation patients.

OBJECTIVE: To compare the risk of stroke/systemic embolism (S/SE) and major bleeding (MB) of elderly (≥65 years of age) nonvalvular atrial fibrillation (NVAF) patients initiating apixaban vs. rivaroxaban, dabigatran, or warfarin. METHODS: NVAF patients with Medicare Advantage coverage in the US initiating oral anticoagulants (OACs, index event) were identified from the Humana database (1 January 2013-30 September 2015) and grouped into cohorts depending on OAC initiated. Propensity score matching (PSM), 1:1, was conducted among patients treated with apixaban vs. each other OAC, separately. Rates of S/SE and MB were evaluated in the follow-up. Cox regressions were used to compare the risk of S/SE and MB between apixaban and each of the other OACs during the follow-up. RESULTS: The matched pairs of apixaban vs. rivaroxaban (n = 13,620), apixaban vs. dabigatran (n = 4654), and apixaban vs. warfarin (n = 14,214) were well balanced for key patient characteristics. Adjusted risks for S/SE (hazard ratio [HR] vs. rivaroxaban: 0.72, p = .003; vs. warfarin: 0.65, p < .001) and MB (HR vs. rivaroxaban: 0.49, p < .001; vs. warfarin: 0.53, p < .001) were significantly lower during the follow-up for patients treated with apixaban vs. rivaroxaban and warfarin. Adjusted risks for S/SE (HR: 0.78, p = .27) and MB (HR: 0.82, p = .23) of NVAF patients treated with apixaban vs. dabigatran trended to be lower, but did not reach statistical significance. CONCLUSIONS: In the real-world setting after controlling for differences in patient characteristics, apixaban is associated with significantly lower risk of S/SE and MB than rivaroxaban and warfarin, and a trend towards better outcomes vs. dabigatran among elderly NVAF patients in the US.

Pulmonary Embolism Inpatients Treated With Rivaroxaban Had Shorter Hospital Stays and Lower Costs Compared With Warfarin.

PURPOSE: Using real-world data, this study compares inpatient length of stay (LOS) and costs for patients with a primary diagnosis of pulmonary embolism (PE) initiating treatment with oral anticoagulation with rivaroxaban versus warfarin. METHODS: Hospitalizations from MarketScan's Hospital Drug Database were selected from November 1, 2012, through December 31, 2013, for adults with a primary diagnosis of PE initiating treatment with rivaroxaban or warfarin. Warfarin patients were matched 1:1 to rivaroxaban patients using exact and propensity score matching. Hospital LOS, treatment patterns, and hospitalization costs were evaluated. FINDINGS: Matched cohorts included 751 rivaroxaban-treated patients and 751 warfarin-treated patients. Adjusted mean LOS was 3.77 days for rivaroxaban patients (95% CI, 3.66-3.87 days) and 5.48 days for warfarin patients (95% CI, 5.33-5.63 days; P < .001). Mean (SD) LOS was shorter for patients taking rivaroxaban whether admission was for provoked PE (rivaroxaban: 5.2 [5.1] days; warfarin: 7.0 [6.5] days; P < .001) or unprovoked PE (rivaroxaban: 3.4 [2.3] days; warfarin: 5.1 [2.7] days; P < .001). Mean (SD) days from first dose to discharge were 2.5 (1.7) (rivaroxaban) and 4.0 (2.9) (warfarin) when initiated with parenteral anticoagulants (P < .001) and 2.7 (1.7) (rivaroxaban) and 4.0 (2.2) (warfarin) without parenteral anticoagulants (P < .001). The rivaroxaban cohort incurred significantly lower unadjusted mean (SD) hospitalization costs (rivaroxaban: $8473 [$9105]; warfarin: $10,291 [$9185]; P < .001), confirmed by covariate adjustment with generalized linear modeling estimating predicted mean hospitalization costs of $8266 for rivaroxaban patients (95% CI, $7851-$8681) and $10,511 for warfarin patients (95% CI, $10,031-$10,992; P < .001). IMPLICATIONS: patients with PE treated with rivaroxaban incurred significantly lower hospitalization costs by $2245 per admission compared with patients treated with warfarin, which was attributable to cost offsets from 1.71 fewer days of stay in the hospital.

Shorter Hospital Stays and Lower Costs for Rivaroxaban Compared With Warfarin for Venous Thrombosis Admissions.

BACKGROUND: Venous thromboembolism, including deep vein thrombosis and pulmonary embolism, results in a substantial healthcare system burden. This retrospective observational study compared hospital length of stay (LOS) and hospitalization costs for patients with venous thromboembolism treated with rivaroxaban versus those treated with warfarin. METHODS AND RESULTS: Hospitalizations for adult patients with a primary diagnosis of deep vein thrombosis or pulmonary embolism who were initiated on rivaroxaban or warfarin were selected from MarketScan's Hospital Drug Database between November 1, 2012, and December 31, 2013. Patients treated with warfarin were matched 1:1 to patients treated with rivaroxaban using exact and propensity score matching. Hospital LOS, time from first dose to discharge, and hospitalization costs were reported descriptively and with generalized linear models (GLMs). The final study cohorts each included 1223 patients (751 with pulmonary embolism and 472 with deep vein thrombosis). Cohorts were well matched for demographic and clinical characteristics. Mean (±SD) LOS was 3.7±3.1 days for patients taking rivaroxaban and 5.2±3.7 days for patients taking warfarin, confirmed by GLM-adjusted results (rivaroxaban 3.7 days, warfarin 5.3 days, P<0.001). Patients with provoked venous thromboembolism admissions showed longer LOSs (rivaroxaban 5.1±4.5 days, warfarin 6.5±5.6 days, P<0.001) than those with unprovoked venous thromboembolism (rivaroxaban 3.3±2.4 days, warfarin 4.8±2.8 days, P<0.001). Days from first dose to discharge were 2.4±1.7 for patients treated with rivaroxaban and 3.9±3.7 for patients treated with warfarin when initiated with parenteral anticoagulants (P<0.001), and 2.7±1.7 and 3.7±2.1, respectively, when initiated without parenteral anticoagulants (P<0.001). Patients initiated on rivaroxaban incurred significantly lower mean total hospitalization costs ($8688±$9927 versus $9823±$9319, P=0.004), confirmed by modeling (rivaroxaban $8387 [95% confidence interval, $8035-$8739]; warfarin $10 275 [95% confidence interval, $9842-$10 708]). CONCLUSIONS: Rivaroxaban was associated with significantly shorter hospital LOS and lower hospitalization costs compared with warfarin.

Hospitalizations and Other Health Care Resource Utilization Among Patients with Deep Vein Thrombosis Treated with Rivaroxaban Versus Low-molecular-weight Heparin and Warfarin in the Outpatient Setting.

PURPOSE: Compared with low-molecular-weight heparin (LMWH) and warfarin, the oral anticoagulant rivaroxaban has advantages, such as simplified care, that may lead to less health care resource utilization. METHODS: A retrospective, matched-cohort analysis was conducted using claims dated between January 2011 and December 2013 from the Truven Health Analytics MarketScan databases. Adult patients who had a primary diagnosis of deep vein thrombosis (DVT) during an outpatient or emergency room (ER) visit after November 2, 2012, and who were treated with rivaroxaban or LMWH/warfarin on the same day, were identified. Patients were observed over 1, 2, 3, and 4 weeks after the DVT diagnosis. The mean numbers of hospitalizations for all causes and for venous thromboembolism (VTE) (which included those for DVT or pulmonary embolism), as well as other health care resource utilization (ER, outpatient, and other visits), and the associated health care costs and pharmacy costs, were evaluated and compared between cohorts using the Lin method. FINDINGS: All of the 512 rivaroxaban-treated patients were well matched with the LMWH/warfarin-treated patients. The mean numbers of all-cause hospitalizations were significantly lower in the rivaroxaban users compared with those in the LMWH/warfarin users over 1 week (0.012 vs 0.032; P = 0.044) and 2 weeks (0.022 vs 0.048; P = 0.040). The corresponding mean numbers of VTE-related hospitalizations were significantly lower with rivaroxaban over 1 week (0.008 vs 0.028; P = 0.020), 2 weeks (0.016 vs 0.042; P = 0.020), and 4 weeks (0.034 vs 0.068; P = 0.036). The mean numbers of all-cause and VTE-related outpatient visits were also significantly lower in rivaroxaban users compared with those in LMWH/warfarin users over 1, 2, 3, and 4 weeks (all, P < 0.001). In terms of all-cause and VTE-related ER and other visits, no statistically significant differences were found between cohorts over the first 4 weeks. The associated mean all-cause total health care costs were significantly lower in the rivaroxaban users compared with those in the LMWH/warfarin users over 1 week (US $2332 vs $3428; P < 0.001) and 2 weeks ($3108 vs $4524; P < 0.001); moreover, significantly lower mean costs related to all-cause hospitalizations (weeks 1 and 2) and pharmacy (weeks 1-4) were observed in patients treated with rivaroxaban, while no differences were found in costs related to ER visits (weeks 1-4), outpatient visits (weeks 1-4), or other visits (with the exception of week 1). IMPLICATIONS: Patients with DVT treated with rivaroxaban after an outpatient/ER visit had significantly lower mean numbers of hospitalizations and outpatient visits, as well as lower mean total, hospitalization, and pharmacy costs during the first 2 weeks of treatment compared with those in matched LMWH/warfarin users.

Target-specific oral anticoagulants and the hospitalist.

As a class, the target-specific oral anticoagulants (TSOACs) are at least as effective as warfarin, often with superior safety for the prevention of stroke in patients with nonvalvular atrial fibrillation (AF) and the treatment of acute venous thromboembolism (VTE) and prevention of recurrent VTE. Currently, dabigatran, the direct thrombin inhibitor, along with rivaroxaban and apixaban, direct factor Xa inhibitors, has been approved in multiple countries for these indications. Edoxaban, which has received approval for the abovementioned indications in Japan, has demonstrated efficacy and safety comparable to or better than warfarin in Phase III clinical trials and is under further regulatory consideration. It is anticipated that the use of TSOACs will increase as practitioners and healthcare systems gain familiarity with these drugs and adopt their use into clinical practice. This review will provide a brief overview of the TSOAC Phase III clinical trials for prevention of stroke and systemic embolic events in patients with AF and the Phase III clinical trials for the prevention of recurrent VTE, discuss current treatment guidelines, address how TSOACs may help meet national safety goals, and provide clinical decision-making guidance regarding the use of TSOACs for hospitalists.

Transitions of care in anticoagulation management for patients with atrial fibrillation.

Thromboprophylaxis with oral anticoagulants (OACs) is an important but underused element of atrial fibrillation (AF) treatment. Reduction of stroke risk with anticoagulants comes at the price of increased bleeding risk. Patients with AF receiving anticoagulants require heightened attention with transition from one care setting to another. Patients presenting for emergency care of anticoagulant-related bleeding should be triaged for the severity and source of the bleeding using appropriate measures, such as discontinuing the OAC, administering vitamin K, when appropriate, to reverse warfarin-induced bleeding, or administering clotting factors for emergent bleeding. Reversal of OACs in patients admitted to the hospital for surgery can be managed similarly to patients with bleeding, depending on the urgency of the surgical procedure. Patients with AF who are admitted for conditions unrelated to AF should be assessed for adequacy of stroke risk prophylaxis and bleeding risk. Newly diagnosed AF should be treated in nearly all patients with either warfarin or a newer anticoagulant. Patient education is critically important with all anticoagulants. Close adherence to the prescribed regimen, regular international normalized ratio testing for warfarin, and understanding the stroke risk conferred by both AF and aging are goals for all patients receiving OACs. Detailed handoff from the hospitalist to the patient's primary care physician is required for good continuity of care. Monitoring by an anticoagulation clinic is the best arrangement for most patients. The elderly, or particularly frail or debilitated patients who are transferring to long-term care, need a detailed transfer of information between settings, education for the patient and family, and medication reconciliation. Communication and coordination of care among outpatient, emergency, inpatient, and long-term care settings are vital for patients with AF who are receiving anticoagulants to balance stroke prevention and bleeding risk.

Warfarin therapy in patients with venous thromboembolism: patterns of use and predictors of clinical outcomes.

INTRODUCTION: Few studies have investigated current practices in the USA relating to warfarin use and monitoring, or the effects of warfarin discontinuation on risk of venous thromboembolism (VTE) and bleeding complications. This study investigated the effect of warfarin discontinuation on rates of VTE recurrence in a real-world setting. METHODS: Integrated Healthcare Information Services database records from January 2003 to September 2007 from patients aged at least 18 years, hospitalized for VTE, and with at least two prescriptions or 60 days of warfarin treatment were reviewed, with warfarin discontinuation and international normalized ratio (INR) data collated. RESULTS: A total of 1027 of 8380 (12.3%) patients discontinued warfarin within 3 months. Overall, 1656 (19.8%) patients had no INR monitoring, with 38.1% of INR values being inside the therapeutic range (INR 2-3). Recurrent VTE was observed in 915 (10.9%) patients. Significant predictors of recurrent VTE (at any time) included discontinuation of warfarin within 3 months, time from index VTE to warfarin initiation, previous VTE-related hospitalization, and duration of index hospitalization. CONCLUSION: This study found that in a real-world population, less than 50% of warfarin patients achieved INR values within the therapeutic range. Warfarin discontinuation within 3 months was associated with a higher rate of recurrent VTE.