Risk of Cardiovascular Events and Mortality Among Elderly Patients With Reduced GFR Receiving Direct Oral Anticoagulants.

RATIONALE & OBJECTIVE: Evidence for the efficacy of direct oral anticoagulants (DOACs) to prevent cardiovascular (CV) events and mortality in older individuals with a low estimated glomerular filtration rate (eGFR) is lacking. We sought to characterize the association of oral anticoagulant use with CV morbidity in elderly patients with or without reductions in eGFRs, comparing DOACs with vitamin K antagonists (VKAs). STUDY DESIGN: Population-based retrospective cohort study. SETTINGS & PARTICIPANTS: All individuals 66 years or older with an initial prescription for oral anticoagulants dispensed in Ontario, Canada, from 2009 to 2016. EXPOSURE: DOACs (apixaban, dabigatran, and rivaroxaban) compared with VKAs by eGFR group (≥60, 30-59, and<30mL/min/1.73m2). OUTCOMES: The primary outcome was a composite of a CV event (myocardial infarction, revascularization, or ischemic stroke) or mortality. Secondary outcomes were CV events alone, mortality, and hemorrhage requiring hospitalization. ANALYTICAL APPROACH: High-dimensional propensity score matching of DOAC to VKA users and Cox proportional hazards regression. RESULTS: 27,552 new DOAC users were matched to 27,552 new VKA users (median age, 78 years; 49% women). There was significantly lower risk for CV events or mortality among DOAC users compared with VKA users (event rates of 79.78 vs 99.77 per 1,000 person-years, respectively; HR, 0.82 [95% CI, 0.75-0.90]) and lower risk for hemorrhage (event rates of 10.35 vs 16.77 per 1,000 person-years, respectively; HR, 0.73 [95% CI, 0.58-0.91]). There was an interaction between eGFR and the association of anticoagulant class with the primary composite outcome (P<0.02): HRs of 1.01 [95% CI, 0.92-1.12], 0.83 [95% CI, 0.75-0.93], and 0.75 [95% CI, 0.51-1.10] for eGFRs of≥60, 30 to 59, and<30mL/min/1.73m2. No interaction was detected for the outcome of hemorrhage. LIMITATIONS: Retrospective observational study design limits causal inference; dosages of DOACs and international normalized ratio values were not available; low event rates in some subgroups limited statistical power. CONCLUSIONS: DOACs compared with VKAs were associated with lower risk for the composite of CV events or mortality, an association for which the strength was most apparent among those with reduced eGFRs. The therapeutic implications of these findings await further study.

Association between rivaroxaban use and length of hospital stay, treatment costs and early outcomes in patients with pulmonary embolism: a systematic review of real-world studies.

BACKGROUND: In the EINSTEIN-Pulmonary Embolism (PE) trial, subjects randomized to rivaroxaban versus enoxaparin bridging to vitamin K antagonist (VKA) therapy experienced a reduced index hospital length of stay (LOS). We sought to conduct a systematic review of real-world studies comparing LOS, costs and early outcomes among patients treated with rivaroxaban or parenterally bridged VKA in routine practice. METHODS: We searched Medline and Scopus from 1 January 2011 to 30 November 2016 to identify observational studies comparing acute PE patients anticoagulated with rivaroxaban or parenterally bridged VKA and reporting data on index hospital LOS, costs and/or early post-PE outcomes. Studies not using appropriate methods for minimizing confounding bias or not published in English were excluded. RESULTS: Five studies met inclusion criteria. Rivaroxaban use was associated with decreased index hospital LOS (range: 1.36-1.70 days) and treatment costs (range: $1818-$2688) during an index stay compared to parenterally bridged warfarin. No differences in early readmission for recurrent thrombosis were noted between anticoagulation strategies. Readmission for major bleeding was rare in both cohorts. Similar reductions in LOS (range: 0.23-4.3 days) and costs (range: $251-$7094) were observed with rivaroxaban in studies restricted to patients deemed low risk for early complications by clinical gestalt or by a clinical- or claims-based risk stratification tool. CONCLUSIONS: Regardless of patient predicted risk of post-PE complications, real-world studies suggest that rivaroxaban is associated with a reduced hospital LOS and costs versus parenterally bridged warfarin, without increasing readmission.

Overall Effectiveness of Rivaroxaban in Patients with Pulmonary Embolism.

PURPOSE: Due to limited evidence on the impact of rivaroxaban in clinical practice, we compared the effectiveness of rivaroxaban versus standard of care (SOC) among patients in the Veterans Health Administration. METHODS: Adult patients with continuous enrollment in a health plan with medical and pharmacy benefits for ≥12 months before and ≥3 months after an inpatient diagnosis of pulmonary embolism (PE) between October 1, 2011, and June 30, 2015, and a prescription claim for an anticoagulant during the index hospitalization, were included. SOC drugs were low-molecular-weight heparin, unfractionated heparin, and warfarin. Propensity score matching was used in comparing PE-related outcomes (recurrent venous thromboembolism, major bleeding, and death), hospital-acquired complications (HACs), health care resource utilization, and costs among patients receiving SOC versus rivaroxaban. We defined net clinical benefit as 1 minus the combined rate of PE-related outcomes and HACs. FINDINGS: Among 6746 patients with PE, 208 received rivaroxaban, 4641 received SOC and 1897 received other anticoagulants. Most (95%) were male; 22% were black. After 1:3 propensity score matching, there were 203 rivaroxaban and 609 SOC patients. During the 90-day follow-up, rivaroxaban users had similar rates of PE-related outcomes, but fewer had experienced at least 1 HAC (10.3% vs 15.9%; P = 0.0506), resulting in better net clinical benefit (82.8% vs 71.1%; P = 0.001). Rivaroxaban users had fewer outpatient visits per patient (17.0 vs 19.9; P = 0.0005), a similar rehospitalization rate (0.2 vs 0.3; P = 0.084), lesser inpatient costs (US $3501 vs $6189; P < 0.0001), lesser inpatient costs and lesser total costs ($10,545 vs $14,192; P = 0.0002). When the sample was limited to patients with low-risk PE, we found similar patterns. IMPLICATIONS: Patients with PE prescribed rivaroxaban had similar PE-related outcomes, but fewer HACs and lesser total costs, than did patients on SOC.

Oral rivaroxaban for the treatment of symptomatic pulmonary embolism.

BACKGROUND: A fixed-dose regimen of rivaroxaban, an oral factor Xa inhibitor, has been shown to be as effective as standard anticoagulant therapy for the treatment of deep-vein thrombosis, without the need for laboratory monitoring. This approach may also simplify the treatment of pulmonary embolism. METHODS: In a randomized, open-label, event-driven, noninferiority trial involving 4832 patients who had acute symptomatic pulmonary embolism with or without deep-vein thrombosis, we compared rivaroxaban (15 mg twice daily for 3 weeks, followed by 20 mg once daily) with standard therapy with enoxaparin followed by an adjusted-dose vitamin K antagonist for 3, 6, or 12 months. The primary efficacy outcome was symptomatic recurrent venous thromboembolism. The principal safety outcome was major or clinically relevant nonmajor bleeding. RESULTS: Rivaroxaban was noninferior to standard therapy (noninferiority margin, 2.0; P=0.003) for the primary efficacy outcome, with 50 events in the rivaroxaban group (2.1%) versus 44 events in the standard-therapy group (1.8%) (hazard ratio, 1.12; 95% confidence interval [CI], 0.75 to 1.68). The principal safety outcome occurred in 10.3% of patients in the rivaroxaban group and 11.4% of those in the standard-therapy group (hazard ratio, 0.90; 95% CI, 0.76 to 1.07; P=0.23). Major bleeding was observed in 26 patients (1.1%) in the rivaroxaban group and 52 patients (2.2%) in the standard-therapy group (hazard ratio, 0.49; 95% CI, 0.31 to 0.79; P=0.003). Rates of other adverse events were similar in the two groups. CONCLUSIONS: A fixed-dose regimen of rivaroxaban alone was noninferior to standard therapy for the initial and long-term treatment of pulmonary embolism and had a potentially improved benefit-risk profile. (Funded by Bayer HealthCare and Janssen Pharmaceuticals; EINSTEIN-PE ClinicalTrials.gov number, NCT00439777.).

Oral rivaroxaban for symptomatic venous thromboembolism.

BACKGROUND: Rivaroxaban, an oral factor Xa inhibitor, may provide a simple, fixed-dose regimen for treating acute deep-vein thrombosis (DVT) and for continued treatment, without the need for laboratory monitoring. METHODS: We conducted an open-label, randomized, event-driven, noninferiority study that compared oral rivaroxaban alone (15 mg twice daily for 3 weeks, followed by 20 mg once daily) with subcutaneous enoxaparin followed by a vitamin K antagonist (either warfarin or acenocoumarol) for 3, 6, or 12 months in patients with acute, symptomatic DVT. In parallel, we carried out a double-blind, randomized, event-driven superiority study that compared rivaroxaban alone (20 mg once daily) with placebo for an additional 6 or 12 months in patients who had completed 6 to 12 months of treatment for venous thromboembolism. The primary efficacy outcome for both studies was recurrent venous thromboembolism. The principal safety outcome was major bleeding or clinically relevant nonmajor bleeding in the initial-treatment study and major bleeding in the continued-treatment study. RESULTS: The study of rivaroxaban for acute DVT included 3449 patients: 1731 given rivaroxaban and 1718 given enoxaparin plus a vitamin K antagonist. Rivaroxaban had noninferior efficacy with respect to the primary outcome (36 events [2.1%], vs. 51 events with enoxaparin-vitamin K antagonist [3.0%]; hazard ratio, 0.68; 95% confidence interval [CI], 0.44 to 1.04; P<0.001). The principal safety outcome occurred in 8.1% of the patients in each group. In the continued-treatment study, which included 602 patients in the rivaroxaban group and 594 in the placebo group, rivaroxaban had superior efficacy (8 events [1.3%], vs. 42 with placebo [7.1%]; hazard ratio, 0.18; 95% CI, 0.09 to 0.39; P<0.001). Four patients in the rivaroxaban group had nonfatal major bleeding (0.7%), versus none in the placebo group (P=0.11). CONCLUSIONS: Rivaroxaban offers a simple, single-drug approach to the short-term and continued treatment of venous thrombosis that may improve the benefit-to-risk profile of anticoagulation. (Funded by Bayer Schering Pharma and Ortho-McNeil; ClinicalTrials.gov numbers, NCT00440193 and NCT00439725.).