Clinical and Economic Outcomes Among Nonvalvular Atrial Fibrillation Patients With Coronary Artery Disease and/or Peripheral Artery Disease.

To address literature gaps on treatment with real-world evidence, this study compared effectiveness, safety, and cost outcomes in NVAF patients with coronary or peripheral artery disease (CAD, PAD) prescribed apixaban versus other oral anticoagulants. NVAF patients aged ≥65 years co-diagnosed with CAD/PAD initiating warfarin, apixaban, dabigatran, or rivaroxaban were selected from the US Medicare population (January 1, 2013 to September 30, 2015). Propensity score matching was used to match apixaban versus warfarin, dabigatran, and rivaroxaban cohorts. Cox models were used to evaluate the risk of stroke/systemic embolism (SE), major bleeding (MB), all-cause mortality, and a composite of stroke/myocardial infarction/all-cause mortality. Generalized linear and two-part models were used to compare stroke/SE, MB, and all-cause costs between cohorts. A total of 33,269 warfarin-apixaban, 9,335 dabigatran-apixaban, and 33,633 rivaroxaban-apixaban pairs were identified after matching. Compared with apixaban, stroke/SE risk was higher in warfarin (hazard ratio [HR]: 1.93; 95% confidence interval [CI]: 1.61 to 2.31), dabigatran (HR: 1.69; 95% CI: 1.18 to 2.43), and rivaroxaban (HR: 1.24; 95% CI: 1.01 to 1.51) patients. MB risk was higher in warfarin (HR: 1.67; 95% CI: 1.52 to 1.83), dabigatran (HR: 1.37; 95% CI: 1.13 to 1.68), and rivaroxaban (HR: 1.87; 95% CI: 1.71 to 2.05) patients vs apixaban. Stroke/SE- and MB-related medical costs per-patient per-month were higher in warfarin, dabigatran, and rivaroxaban patients versus apixaban. Total all-cause health care costs were higher in warfarin and rivaroxaban patients compared with apixaban patients. In conclusion, compared with apixaban, patients on dabigatran, rivaroxaban, or warfarin had a higher risk of stroke/SE, MB, and event-related costs.

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.

Effectiveness and Safety of Anticoagulants in Adults with Non-valvular Atrial Fibrillation and Concomitant Coronary/Peripheral Artery Disease.

BACKGROUND: Direct oral anticoagulants (DOAC) are at least non-inferior to warfarin in efficacy and safety among patients with nonvalvular atrial fibrillation. Limited evidence is available regarding outcomes for nonvalvular atrial fibrillation patients with coronary/peripheral artery disease. METHODS: Non-valvular atrial fibrillation patients aged ≥65 years diagnosed with coronary/peripheral artery disease in the US Medicare population, newly initiating DOACs (apixaban, rivaroxaban, dabigatran) or warfarin were selected from January 1, 2013 to September 30, 2015. Propensity score matching was used to compare DOACs vs warfarin. Cox proportional hazards models were used to estimate the risk of stroke/systemic embolism, major bleeding, and composite of stroke/myocardial infarction/all-cause mortality. RESULTS: There were 15,527 apixaban-warfarin, 6,962 dabigatran-warfarin, and 25,903 rivaroxaban-warfarin-matched pairs, with a mean follow-up of 5-6 months. Compared with warfarin, apixaban was associated with lower rates of stroke/systemic embolism (hazard ratio [HR] 0.48; 95% confidence interval [CI], 0.37-0.62), major bleeding (HR 0.66; 95% CI, 0.58-0.75), and stroke/myocardial infarction/all-cause mortality (HR 0.63; 95% CI, 0.58-0.69); dabigatran and rivaroxaban were associated with lower rates of stroke/myocardial infarction/all-cause mortality (HR 0.79; 95% CI, 0.70-0.90 and HR 0.87; 95% CI, 0.81-0.92, respectively). Rivaroxaban was associated with a lower rate of stroke/systemic embolism (HR 0.72; 95% CI, 0.60-0.89) and a higher rate of major bleeding (HR 1.14; 95% CI, 1.05-1.23) vs warfarin. CONCLUSIONS: All DOACs were associated with lower stroke/myocardial infarction/all-cause mortality rates compared with warfarin; differences were observed in rates of stroke/systemic embolism and major bleeding. Findings from this observational analysis provide important insights about oral anticoagulation therapy among non-valvular atrial fibrillation patients with coronary/peripheral artery disease and may help physicians in the decision-making process when treating this high-risk group of patients.

Real-world comparison of major bleeding risk among non-valvular atrial fibrillation patients initiated on apixaban, dabigatran, rivaroxaban, or warfarin. A propensity score matched analysis.

In addition to warfarin, there are four non-vitamin K antagonist oral anticoagulants (NOACs) available for stroke prevention in non valvular atrial fibrillation (NVAF). There are limited data on the comparative risks of major bleeding among newly anticoagulated NVAF patients who initiate warfarin, apixaban, dabigatran, or rivaroxaban, when used in 'real world' clinical practice. The study used the Truven MarketScan® Commercial & Medicare supplemental US claims database. NVAF patients aged ≥18 years newly prescribed an oral anticoagulant 01JAN2013-31DEC2014, with a ≥1-year baseline period, were included (study period: 01JAN2012-31DEC2014). Major bleeding was defined as bleeding requiring hospitalisation. Propensity score matching (PSM) was used to balance age, sex, region, baseline comorbidities, and comedications. Cox proportional hazards models were used to estimate the PSM hazard ratio (HR) of major bleeding. Among 45,361 newly anticoagulated NVAF patients, 15,461 (34.1 %) initiated warfarin, 7,438 (16.4 %) initiated apixaban, 17,801 (39.2 %) initiated rivaroxaban, and 4,661 (10.3 %) initiated dabigatran. Compared to matched warfarin initiators, apixaban (HR: 0.53; 95 % CI: 0.39-0.71) and dabigatran (HR: 0.69; 95 % CI: 0.50-0.96) initiators had a significantly lower risk of major bleeding. Patients initiating rivaroxaban (HR: 0.98; 95 % CI: 0.83-1.17) had a non-significant difference in major bleeding risk compared to matched warfarin patients. When comparisons were made between NOACs, matched rivaroxaban patients had a significantly higher risk of major bleeding (HR: 1.82; 95 % CI: 1.36-2.43) compared to apixaban patients. The differences for apixaban-dabigatran and dabigatran-rivaroxaban matched cohorts were not statistically significant. Among newly anticoagulated NVAF patients in the real-world setting, apixaban and dabigatran initiation was associated with significantly lower risk of major bleeding compared to warfarin initiation. When compared to apixaban, rivaroxaban initiation was associated with significantly higher risk of major bleeding.

Major bleeding risk among non-valvular atrial fibrillation patients initiated on apixaban, dabigatran, rivaroxaban or warfarin: a "real-world" observational study in the United States.

BACKGROUND: Limited data are available about the real-world safety of non-vitamin K antagonist oral anticoagulants (NOACs). OBJECTIVES: To compare the major bleeding risk among newly anticoagulated non-valvular atrial fibrillation (NVAF) patients initiating apixaban, warfarin, dabigatran or rivaroxaban in the United States. METHODS AND RESULTS: A retrospective cohort study was conducted to compare the major bleeding risk among newly anticoagulated NVAF patients initiating warfarin, apixaban, dabigatran or rivaroxaban. The study used the Truven MarketScan(®) Commercial & Medicare supplemental US database from 1 January 2013 through 31 December 2013. Major bleeding was defined as bleeding requiring hospitalisation. Cox model estimated hazard ratios (HRs) of major bleeding were adjusted for age, gender, baseline comorbidities and co-medications. Among 29 338 newly anticoagulated NVAF patients, 2402 (8.19%) were on apixaban; 4173 (14.22%) on dabigatran; 10 050 (34.26%) on rivaroxaban; and 12 713 (43.33%) on warfarin. After adjusting for baseline characteristics, initiation on warfarin [adjusted HR (aHR): 1.93, 95% confidence interval (CI): 1.12-3.33, P=.018] or rivaroxaban (aHR: 2.19, 95% CI: 1.26-3.79, P=.005) had significantly greater risk of major bleeding vs apixaban. Dabigatran initiation (aHR: 1.71, 95% CI: 0.94-3.10, P=.079) had a non-significant major bleeding risk vs apixaban. When compared with warfarin, apixaban (aHR: 0.52, 95% CI: 0.30-0.89, P=.018) had significantly lower major bleeding risk. Patients initiating rivaroxaban (aHR: 1.13, 95% CI: 0.91-1.41, P=.262) or dabigatran (aHR: 0.88, 95% CI: 0.64-1.21, P=.446) had a non-significant major bleeding risk vs warfarin. CONCLUSION: Among newly anticoagulated NVAF patients in the real-world setting, initiation with rivaroxaban or warfarin was associated with a significantly greater risk of major bleeding compared with initiation on apixaban. When compared with warfarin, initiation with apixaban was associated with significantly lower risk of major bleeding. Additional observational studies are required to confirm these findings.