Effectiveness and safety in non-valvular atrial fibrillation patients switching from warfarin to direct oral anticoagulants in US healthcare claims

INTRODUCTION

There is a paucity of real-world studies examining the risks of stroke/systemic embolism (SE) and major bleeding (MB) among non-valvular atrial fibrillation (NVAF) patients switching from warfarin to a direct oral anticoagulant (DOAC). This retrospective study was conducted to compare the stroke/SE and MB risks between patients switched from warfarin to apixaban, dabigatran, or rivaroxaban in real-world clinical practice.

MATERIALS AND METHODS

This study used data from four United States commercial claims databases from January 1, 2012 to June 30, 2019. The study population included NVAF patients initially treated with warfarin and switched to apixaban, dabigatran, or rivaroxaban within 90 days of their warfarin prescription ending. Patients were matched 1:1 between the DOACs in each database using propensity scores and then pooled for the final analysis. Cox proportional hazards models were used to calculate the risk of stroke/SE and MB.

RESULTS AND CONCLUSIONS

The final population consisted of 2,611 apixaban-dabigatran, 12,165 apixaban-rivaroxaban, and 2,672 dabigatran-rivaroxaban pairs. Apixaban vs. dabigatran was associated with a lower risk of stroke/SE (hazard ratio [HR]: 0.61; 95% confidence interval [CI]: 0.39-0.96) and MB (HR: 0.67; 95% CI: 0.50-0.91). Apixaban vs. rivaroxaban was associated with a similar risk of stroke/SE (HR: 0.88; 95% CI: 0.73-1.07) and a lower risk of MB (HR: 0.60; 95% CI: 0.52-0.68). There was no significant difference in either risk between dabigatran and rivaroxaban. These results provide important insights into how the risks of stroke/SE and MB for NVAF patients vary when switching from warfarin to different DOACs.

Clinical Impact of Switching or Continuation of Apixaban or Rivaroxaban among Patients with Non-Valvular Atrial Fibrillation

BACKGROUND

Real-world evidence on direct oral anticoagulant outcomes among Non-Valvular Atrial Fibrillation (NVAF) patients is limited. We aimed to evaluate stroke/systemic embolism (SE) and major bleeding (MB) risks among NVAF patients continuing or switching to different oral anticoagulants.

METHODS

Using Optum's de-identified Clinformatics® Data Mart Database, we identified NVAF patients initiating apixaban or rivaroxaban between 1 January 2013 and 31 December 2021. Patients switching therapies within 30 days before or 90 days after discontinuing their initial DOAC and those who continued initial therapy were included. The index date was the switch date for switchers, while continuers were assigned a hypothetic index date. Switchers and continuers were propensity score matched based on pre-index characteristics.

RESULTS

Among 167,868 apixaban and 65,888 rivaroxaban initiators, 2900 apixaban-to-rivaroxaban switchers were matched with 14,500 apixaban continuers, and 2873 rivaroxaban-to-apixaban switchers were matched with 14,365 rivaroxaban continuers. Apixaban-to-rivaroxaban switching was associated with higher stroke/SE risk (HR: 1.99, 95% CI: 1.38-2.88) and MB risk (HR:1.80, 95% CI: 1.46-2.23) than continuing apixaban. Rivaroxaban-to-apixaban switching had similar stroke/SE risk (HR: 0.74, 95% CI: 0.45-1.22) but lower MB risk (HR: 0.49, 95% CI: 0.38-0.65) than continuing rivaroxaban.

CONCLUSIONS

These findings may aid physicians and patients in making informed decisions when considering a switch between apixaban and rivaroxaban.

Journey to anticoagulant access following payer rejection of apixaban

OBJECTIVES

To investigate the journey to oral anticoagulant (OAC) access following formulary-related rejection of apixaban (Eliquis) and evaluate characteristics associated with failure to achieve OAC access among patients with atrial fibrillation (AF).

STUDY DESIGN

Retrospective study using the Optum Market Clarity Data from January 2016 through February 2020.

METHODS

Patients had at least 1 claim rejection for apixaban due to prior authorization (PA), formulary exclusion (FE), or quantity limit (QL) and at least 1 AF diagnosis on or before the rejected claim. Descriptive statistics summarized transaction journeys by type of formulary restriction. Multivariable regression assessed patient characteristics associated with not receiving an OAC within 60 days after initial rejection.

RESULTS

Among 18,434 patients in the analytic sample, QL was the most common reason for rejection (68.7%), followed by PA (21.2%) and FE (10.2%). Most patients received a paid OAC claim within 60 days after rejection (82.2%-85.5% across restriction types). Mean time from rejection to paid claim ranged from 5.2 to 10.7 days among patients with a paid OAC claim and 12.4 to 17.6 days among those with multiple attempts before OAC receipt. Characteristics associated with higher odds of not receiving OAC treatment included being male, beingAfrican American, having Medicaid coverage, possessing a high stroke risk score, exhibiting no evidence of prior apixaban treatment, and being prescribed a low dose of apixaban on the initial rejected claim.

CONCLUSIONS

Most patients with a claim rejection for apixaban received approval for apixaban within 60 days, suggesting that initial rejection merely created a delay in treatment. Vulnerable populations were at greater risk of not receiving a paid OAC claim.

Payer formulary tier increases of apixaban: how patients respond and potential implications

OBJECTIVE

To assess potential impacts of formulary tier increases of apixaban-an efficacious oral anticoagulant (OAC) for preventing stroke in patients with atrial fibrillation (AF)-on patients' prescription drug plan (PDP) switching and OAC treatment patterns.

METHODS

Nationwide claims data for Medicare beneficiaries with Parts A, B, and D (100% sample) were used to assess apixaban-treated AF patients who faced a formulary tier increase for apixaban in 2017 by their Part D PDP. Patients' out-of-pocket (OOP) costs for apixaban were described, along with PDP switching and OAC treatment patterns.

RESULTS

Among 1845 included patients, 97.7% had apixaban on tier 3 of their plan's formulary in 2016 and faced its increase to tier 4 for 2017. Approximately 4% (N = 81) of patients pre-emptively switched to a different PDP for 2017 with almost all switching to plans with apixaban on a lower formulary tier and 85.2% continuing apixaban treatment. Among the 96% (N = 1764) of patients who remained on the same PDP for 2017, over half (57.5%) continued apixaban treatment, despite increased OOP costs ($54 vs. $135 for a 30-day supply in 2016 vs. 2017). Only 12.4% of those who remained on the same plan for 2017 switched to another OAC, while as much as 30.1% discontinued OACs. These discontinuers exhibited higher comorbidity burdens than patients continuing on any OAC.

CONCLUSION

The majority of patients continued on apixaban despite higher OOP cost, suggesting patients' reluctance to change treatment for non-medical reasons; however, 30% of patients discontinued OAC treatment after higher apixaban tier placement.

Delaying clinical events among patients with non-valvular atrial fibrillation treated with oral anticoagulants: Insights from the ARISTOPHANES study

BACKGROUND

Oral anticoagulants (OACs) mitigate stroke and systemic embolism (SE) risk in non-valvular atrial fibrillation (AF) patients but can increase the risk of major bleeding (MB). This study analyzed the gains in event-free time for these outcomes among OAC treatment options represented in the ARISTOPHANES study.

METHODS

This sub-analysis consisted of NVAF patients who initiated warfarin, apixaban, dabigatran, or rivaroxaban from 01JAN2013-30SEP2015, with data pooled from Medicare and 4 US commercial claims databases. Propensity score matching was conducted between non-vitamin K antagonist OAC (NOAC) and warfarin cohorts in each database and results were pooled. Laplace regression was used to evaluate the delay in time to stroke/SE and MB events between NOACs and warfarin and between NOACs after the first 12-months of follow-up.

RESULTS

The population included 466,991 patients (167,413 warfarin; 108,852 apixaban; 37,724 dabigatran; and 153,002 rivaroxaban). Event-free time gain (95% confidence interval) for apixaban versus warfarin was 101 days (78- 124) for stroke/SE and 116 (103- 130) days for MB. The gain in event-free time for dabigatran versus warfarin was 45 days (3- 87) for stroke/SE and 92 (68- 116) days for MB. The gain in event-free time for rivaroxaban versus warfarin was 63 days (42- 84) for stroke/SE but event-free time decreased by 18 (-31-6) days for MB.

CONCLUSIONS

Over 12 months after initiation, apixaban and dabigatran conferred progressive increases in event free time for stroke/SE and MB vs warfarin, whereas rivaroxaban conferred an increase in stroke/SE-free time but a loss in MB-free time vs warfarin.

Impact of apixaban treatment discontinuation on the risk of hospitalization among patients with nonvalvular atrial fibrillation and COVID-19

INTRODUCTION

This study evaluated the risk of hospitalization among nonvalvular atrial fibrillation (NVAF) patients with an outpatient COVID-19 diagnosis who discontinued vs continued apixaban treatment.

METHODS

Adult patients with NVAF with an apixaban prescription prior to an outpatient COVID-19 diagnosis were identified from Optum Clinformatics claims database (1 April 2020-31 March 2021). Continuers were those who continued apixaban as of the index date (date of initial outpatient COVID-19 diagnosis) and discontinuers were those who had the last day of apixaban supply on or before index. Patients were followed from COVID-19 diagnosis to change of continuation/discontinuation status, switch, death, end of continuous coverage or study end, whichever occurred first. Inverse probability treatment weighting (IPTW) was performed to balance cohorts. Cox proportional hazard models were used to compare the risk of all-cause hospitalization and hospitalization for ischemic stroke (IS), venous thromboembolism (VTE), myocardial infarction (MI), bleeding and mortality.

RESULTS

A total of 7869 apixaban patients with COVID-19 were included: 6676 continuers (84.8%) and 1193 discontinuers (15.2%). Compared with continuers, discontinuers had a higher risk of all-cause hospitalization (hazard ratio [HR]: 1.23; 95% confidence interval [CI]: 1.08-1.40), IS (HR: 2.00; 95% CI: 1.03-3.87), VTE (HR: 2.37; 95% CI: 1.06-5.27) and mortality (HR: 2.28; 95% CI: 1.85-2.80). There were no significant differences in the risk of MI (HR: 1.01; 95% CI: 0.54-1.90) or bleeding-related hospitalization (HR: 1.13; 95% CI: 0.73-1.76).

CONCLUSION

NVAF patients with COVID-19 who discontinued apixaban had a higher risk of hospitalization and thrombotic events vs those who continued apixaban, with no significant difference in bleeding-related hospitalization.

Payer formulary exclusions of apixaban: how patients respond and potential implications

In recent years, US payers have increased usage of formulary exclusions as a means to help manage costs. Earlier this year, one of the largest pharmacy benefit managers in the country added Eliquis (apixaban), the most widely used anticoagulant, to its list of excluded medicines from its formulary, raising concerns by physicians and patients. In this commentary, we examine the potential impacts of formulary exclusion of a drug like apixaban-a treatment for patients with atrial fibrillation and venous thromboembolism to help prevent stroke and clotting events and which has been demonstrated to have a strong efficacy and safety profile. We discuss the effect of formulary exclusions on patients' ability to access the most clinically appropriate treatment for their health needs, along with possible effects on their health and well-being. We also report descriptive results on apixaban-treated patients with traditional Medicare coverage who faced a formulary exclusion of apixaban in 2017, and these patients' observed behaviors. We found that the majority of these patients remained on apixaban either through pre-emptively switching to a different Part D drug plan with apixaban coverage or applying for formulary exception. Our findings suggest that formulary exclusion did not help to achieve the goal of switching patients to less costly medications but created additional hurdles for patients to access their preferred treatment and increased patient burden. Alternative ways to manage payer costs may be needed to help avoid poor outcomes and reduce the burden placed on patients in their efforts to access life-saving medications.

Risk Levels and Adverse Clinical Outcomes Among Patients With Nonvalvular Atrial Fibrillation Receiving Oral Anticoagulants

IMPORTANCE

The CHA2DS2-VASc score (calculated as congestive heart failure, hypertension, age 75 years and older, diabetes, stroke or TIA, vascular disease, age 65 to 74 years, and sex category) is the standard for assessing risk of stroke and systemic embolism and includes age and thromboembolic history. To our knowledge, no studies have comprehensively evaluated safety and effectiveness outcomes among patients with nonvalvular atrial fibrillation receiving oral anticoagulants according to independent, categorical risk strata.

OBJECTIVE

To evaluate the incidence of key adverse outcomes among patients with nonvalvular atrial fibrillation receiving oral anticoagulants by CHA2DS2-VASc risk score range, thromboembolic event history, and age group.

DESIGN, SETTING, AND PARTICIPANTS

This cohort study was a retrospective claims data analysis using combined data sets from 5 large health claims databases. Eligible participants were adult patients with nonvalvular atrial fibrillation who initiated oral anticoagulants. Data were analyzed between January 2012 and June 2019.

EXPOSURE

Initiation of oral anticoagulants.

MAIN OUTCOMES AND MEASURES

We observed clinical outcomes (including stroke or systemic embolism, major bleeding, and a composite outcome) on treatment through study end, censoring for discontinuation of oral anticoagulants, death, and insurance disenrollment. The population was stratified by CHA2DS2-VASc risk score; history of stroke, systemic embolism, or transient ischemic attack; and age groups. We calculated time to event, incidence rates, and cumulative incidence for outcomes.

RESULTS

We identified 1 141 097 patients with nonvalvular atrial fibrillation; the mean (SD) age was 75.0 (10.5) years, 608 127 patients (53.3%) were men, and over 1 million were placed in the 2 highest risk categories (high risk 1, 327 766 participants; high risk 2, 688 449 participants). Deyo-Charlson Comorbidity Index scores ranged progressively alongside CHA2DS2-VASc risk score strata (mean [SD] scores: low risk, 0.4 [1.0]; high risk 2, 4.1 [2.9]). The crude incidence of stroke and systemic embolism generally progressed alongside risk score strata (low risk, 0.25 events per 100 person-years [95% CI, 0.18-0.34 events]; high risk 2, 3.43 events per 100 person-years [95% CI, 3.06-4.20 events]); patients at the second-highest risk strata with thromboembolic event history had higher stroke incidence vs patients at the highest risk score strata without event history (2.06 events per 100 person-years [95% CI, 2.00-3.12 events] vs 1.18 events per 100 person-years [95% CI, 1.14-1.30 events]). Major bleeding and composite incidence also increased progressively alongside risk score strata (major bleeding: low risk, 0.68 events per 100 person-years [95% CI, 0.56-0.82 events]; high risk 2, 6.29 events per 100 person-years [95% CI, 6.21-6.62 events]; composite incidence: 1.22 events per 100 person-years [95% CI, 1.06-1.41 events]; high risk 2, 10.67 events per 100 person-years [95% CI, 10.26-11.48 events]). The 12-month cumulative incidence proportions for stroke and systemic embolism, major bleeding, and composite outcomes progressed alongside risk score strata (stroke or systemic embolism, 0.30%-1.85%; major bleeding, 0.55%-5.55%; composite, 1.05%-8.23%). Age subgroup analysis followed similar trends.

CONCLUSIONS AND RELEVANCE

The observed incidence of stroke or systemic embolism and major bleeding events generally conformed to an expected increasing incidence by risk score, adding insight into the importance of specific risk score range, thromboembolic event history, and age group strata. These results can help inform clinical decision-making, research, and policy.

Effectiveness and safety of oral anticoagulants in non-valvular atrial fibrillation patients with prior bleeding events: a retrospective analysis of administrative claims databases

Introduction

There are a paucity of real-world data examining effectiveness and safety of non-vitamin K antagonist oral anticoagulants (NOACs) and warfarin in nonvalvular atrial fibrillation (NVAF) patients with prior bleeding.

Methods

This retrospective analysis included data from 5 insurance claims databases and included NVAF patients prescribed OACs with prior bleeding. One-to-one propensity score matching was conducted between NOACs and warfarin and between NOACs in each database. Cox proportional hazards models were used to evaluate the risk of stroke/systemic embolism (SE) and MB.

Results

A total of 244,563 patients (mean age 77; 50% female) with prior bleeding included 55,094 (22.5%) treated with apixaban, 12,500 (5.1%) with dabigatran, 38,246 (15.6%) with rivaroxaban, and 138,723 (56.7%) with warfarin. Apixaban (hazard ratio [HR]: 0.76 [95% CI: 0.70, 0.83]) and rivaroxaban (HR: 0.79 [95% CI: 0.71, 0.87]) had a lower risk of stroke/SE vs. warfarin. Apixaban (HR: 0.67 [95% CI: 0.64, 0.70]) and dabigatran (HR: 0.88 [95% CI: 0.81, 0.96]) had a lower risk of MB vs. warfarin. Apixaban patients had a lower risk of stroke/SE vs. dabigatran (HR: 0.70 [95% CI: 0.57, 0.86]) and rivaroxaban (HR: 0.85 [95% CI: 0.76, 0.96]) and a lower risk of MB than dabigatran (HR: 0.73 [95% CI: 0.67, 0.81]) and rivaroxaban (HR: 0.64 [95% CI: 0.61, 0.68]).

Conclusions

In this real-world analysis of a large sample of NVAF patients with prior bleeding, NOACs were associated with similar or lower risk of stroke/SE and MB vs. warfarin and variable risk of stroke/SE and MB against each other.

Supplementary information

The online version contains supplementary material available at 10.1007/s11239-022-02660-2.

Data on NOAC effectiveness and safety in NVAF patients with prior bleed history are lacking.

This study included data on OAC-treated NVAF patients with a history of bleeding.

NOACs were associated with similar or lower risk of stroke/SE and MB vs. warfarin.

NOACs were associated with variable risk of stroke/SE and MB against each other.

This study further demonstrated the effectiveness and safety profile when comparing NOACs to warfarin. The findings could aid to inform the discussion on the benefits and risks in the decision making process for NVAF patients who had a prior bleed.

Real-world evidence comparing oral anticoagulants in non-valvular atrial fibrillation: a systematic review and network meta-analysis

Aim: To compare real-world effectiveness/safety of non-vitamin K antagonist oral anticoagulants and vitamin K antagonists among patients with non-valvular atrial fibrillation. Materials & methods: A systematic review of electronic databases yielded 7661 citations published from January 2013 to January 2020. Fifty-five studies were included in Bayesian network meta-analyses of hazard ratios. Results & conclusion: In comparison with vitamin K antagonists, apixaban, dabigatran and rivaroxaban were associated with a reduced risk of stroke or systemic embolism, ischemic stroke, intracranial hemorrhage and all-cause mortality. Apixaban, dabigatran and edoxaban, but not rivaroxaban, were associated with a reduced risk of major bleeding. This study confirmed the effectiveness and safety of non-vitamin K antagonist oral anticoagulants for the treatment of non-valvular atrial fibrillation in real-world settings, consistent with clinical trial evidence.

The Impact of American College of Cardiology Chest Pain Center Accreditation on Guideline Recommended Acute Myocardial Infarction Management

BACKGROUND

Whether American College of Cardiology (ACC) Chest Pain Center (CPC) accreditation alters guidelines adherence rates is unclear.

METHODS

We analyzed patient-level, hospital-reported, quality metrics for myocardial infarction (MI) patients from 644 hospitals collected in the ACC's Chest Pain-MI Registry from January 1, 2019, to December 31, 2020, stratified by CPC accreditation for >1 year.

RESULTS

Of 192,374 MI patients, 67,462 (35.1%) received care at an accredited hospital. In general, differences in guideline adherence rates between accredited and nonaccredited hospitals were numerically small, although frequently significant. Patients at accredited hospitals were more likely to undergo coronary angiography (98.6% vs. 97.9%, P < 0.0001), percutaneous coronary intervention for NSTEMI (55.4% vs. 52.3%, P < 0.0001), have overall revascularization for NSTEMI (63.5% vs. 61.0%, P < 0.0001), and receive P2Y12 inhibitor on arrival (63.5% vs. 60.2%, P < 0.0001). Nonaccredited hospitals more ECG within 10 minutes (62.3% vs. 60.4%, P < 0.0001) and first medical contact to device activation ≤90 minutes (66.8% vs. 64.8%, P < 0.0001). Accredited hospitals had uniformly higher discharge medication guideline adherence, with patients more likely receiving aspirin (97.8% vs. 97.4%, P < 0.0001), angiotensin-converting enzyme inhibitor (46.7% vs. 45.3%, P < 0.0001), beta blocker (96.6% vs. 96.2%, P < 0.0001), P2Y12 inhibitor (90.3% vs. 89.2%, P < 0.0001), and statin (97.8% vs. 97.5%, P < 0.0001). Interaction by accredited status was significant only for length of stay, which was slightly shorter at accredited facilities for specific subgroups.

CONCLUSIONS

ACC CPC accreditation was associated with small consistent improvement in adherence to guideline-based treatment recommendations of catheter-based care (catheterization and PCI) for NSTEMI and discharge medications, and shorter hospital stays.

Effectiveness and safety of non-vitamin K antagonist oral anticoagulants versus warfarin among nonvalvular atrial fibrillation patients with prior bleeding events

Background

Patients with non-valvular atrial fibrillation (NVAF) use oral anticoagulants such as warfarin or non-vitamin K antagonist oral anticoagulants (NOACs) for the prevention of stroke. However, the effectiveness and safety of warfarin and NOACs can be influenced by pre-existing patient comorbidities, such as a history of bleeding, and limited evidence are available to inform the choice of the most appropriate anticoagulant treatment for NVAF patients with bleeding history.

Purpose

This study used five United States insurance claims databases to evaluate the risk of stroke/systemic embolism (S/SE) and major bleeding (MB) among NVAF patients with prior bleeding events who were prescribed NOACs versus warfarin.

Methods

This retrospective observational study used data from 5 databases (CMS Medicare and four commercial databases, covering &gt;180 million beneficiaries) to select adult NVAF patients who were treated with apixaban, dabigatran, rivaroxaban, or warfarin (01JAN2013–30JUN2019). Patients were required to have a prior bleeding event, defined as a hospitalization with a diagnosis for intracranial hemorrhage (ICH), gastrointestinal (GI) bleeding or bleeding at other key sites prior to or during the index treatment episode. In each database, three 1:1 NOAC-warfarin propensity-score-matched (PSM) cohorts were created before pooling the results. Outcome measures were time to first stroke/SE, (ischemic stroke, hemorrhagic stroke, and SE), and time to first MB (gastrointestinal bleeding, intracranial hemorrhage, and MB at other key sites), and were measured from the index treatment episode to treatment discontinuation or switch, death, health plan disenrollment, or end of study period. Hazard ratios of S/SE and MB were calculated using Cox proportional hazards models.

Results

Among the eligible NVAF population, 8.2% of patients had a prior bleeding event (ICH: 12.3%; GI: 60.7%; Other: 27.0%). After PSM, a total of 43,092 apixaban-warfarin, 11,295 dabigatran-warfarin, and 32,723 rivaroxaban-warfarin patient pairs with prior bleeding were selected with a mean follow-up of 8–9 months. Apixaban and rivaroxaban were associated with a lower risk of S/SE, and dabigatran was associated with a similar risk of S/SE when compared to warfarin. Apixaban and dabigatran were associated with a lower risk of MB, and rivaroxaban was associated with a similar risk of MB, compared to warfarin (Figure).

Conclusion

Among NVAF patients with prior bleeding events, NOACs were associated with varying risks of S/SE and MB compared to warfarin. These results can help inform healthcare providers concerning the impact of OAC treatment in NVAF patients with history of bleeding.

Funding Acknowledgement

Type of funding sources: Private company. Main funding source(s): Bristol-Myers Squibb Company and Pfizer, Inc.

Time at home among nonvalvular atrial fibrillation patients treated with non-vitamin K antagonist oral anticoagulants: an ARISTOPHANES analysis

Background

Patient-centered outcomes, such as home time, are becoming increasingly important quality-of-life measures. There are limited data on the impact of oral anticoagulants (OACs) on home time among patients with non-valvular atrial fibrillation.

Purpose

This analysis, based on the previously published ARISTOPHANES study, used five US insurance claims databases (CMS Medicare and four commercial databases) to compare home time among NVAF patients who were prescribed non-vitamin K antagonist OACs (NOACs).

Methods

Adult NVAF patients who were newly prescribed apixaban, dabigatran, or rivaroxaban (01JAN2013–30SEP2015) were selected. Time at home was calculated as the number of days from the index date (NOAC prescription) without any of the following: an inpatient, skilled nursing facility (SNF) or nursing facility, hospice, or inpatient rehabilitation facility admission. Time at home and without external AF-related care was defined as days from index date without any events from the home time endpoint or any days with a claim for bleeding, stroke/systemic embolism (S/SE), AF, or an INR test. Time at home and without external AF-related care were measured during the 180 days of follow-up; patients were required to have been alive and have 180 days of follow-up post index. In each database, three 1:1 NOAC-NOAC propensity-score-matched (PSM) cohorts were created before combining the databases. For each NOAC-NOAC matched cohort, Poisson regression was conducted to compare time at home and time at home without external AF-related care.

Results

After PSM, 37,314 apixaban-dabigatran, 107,236 apixaban-rivaroxaban, and 37,693 rivaroxaban-dabigatran patient pairs were created of which 37–44% had 180 days of follow-up available. Across the NOAC cohorts, approximately 21–25% of patients had an admission to a hospital, SNF, nursing facility, rehabilitation center, or hospice during the 180-day follow-up. The time at home was generally consistent between the NOAC cohorts (177 days); however, apixaban patients had 0.5 more days at home compared to rivaroxaban patients. Across all NOAC cohorts, 7–8% had a claim for a S/SE, 11–15% had a claim for bleeding, and 15–22% had an INR test, while 87–89% of all patients had an AF-claim during the 180-day follow-up. Patients prescribed apixaban had 1 more day at home without external AF-related care compared to dabigatran, and 1.5 more days at home without external AF-related care compared to rivaroxaban. Dabigatran had &lt;1 more day at home without external AF-related care compared to rivaroxaban.

Conclusion

Among NVAF patients treated with NOACs, there were small differences in the time at home and time at home without external AF-related care during the first 6 months of NOAC treatment. As NVAF is a chronic condition, it is important to understand the impact of NOAC treatment on these patient-centered outcomes.

Funding Acknowledgement

Type of funding sources: Private company. Main funding source(s): Bristol-Myers Squibb Company and Pfizer Inc.

Time at home among nonvalvular atrial fibrillation patients treated with non-vitamin K antagonist oral anticoagulants versus warfarin

Background

Clinical trials and real-world database studies have shown the benefits of non-vitamin K antagonist oral anticoagulants (NOACs) compared to warfarin; however, measures of functional outcomes are critical in evaluating a patient's quality of life. Previous measures of time spent out of hospital in a home setting and time spent receiving disease-related care among non-valvular atrial fibrillation (NVAF) patients are lacking in the current literature.

Purpose

This analysis was based on the previously published ARISTOPHANES study, and used multiple data sources to evaluate the amount of time spent at a patient's home among NVAF patients who were prescribed NOACs versus warfarin.

Methods

This retrospective observational study used US data from CMS Medicare and four commercial databases to select adult NVAF patients who initiated apixaban, dabigatran, rivaroxaban, or warfarin (01JAN2013–30SEP2015). Time at home and time at home without external AF-related care were measured during the 180 days after the index date (OAC prescription). Time at home was defined as days from index date without any of the following: an inpatient, skilled nursing facility or nursing facility, hospice, or inpatient rehabilitation facility admission. Time at home and without external AF-related care was defined as days away from home and days with a claim for bleeding, stroke/systemic embolism, AF, or an INR test. Each day a claim was observed was counted as one day. In each database, three 1:1 NOAC-warfarin propensity-score-matched (PSM) cohorts were created before pooling the results. After PSM, a subgroup of patients who were alive and had ≥180 days of follow-up was created. Poisson regression was conducted in each NOAC-warfarin matched cohort to compare time at home and time at home without external AF-related care.

Results

After matching, a total of 100,977 apixaban-warfarin, 36,990 dabigatran-warfarin, and 125,068 rivaroxaban-warfarin patient pairs were selected. Of those patients, 38–46% had 180 days of follow-up available. Across treatment cohorts, approximately 75% of patients were at home for the 180-day follow-up. Apixaban, dabigatran, and rivaroxaban patients had 1.3, 0.9, and 0.8 more days at home, respectively, compared to warfarin patients. Patients treated with apixaban had 13.4 more days at home without AF-related care compared to warfarin, while dabigatran and rivaroxaban had 11.6 and 11.7 more days at home without AF-related care compared to warfarin. A greater proportion of warfarin patients than NOAC patients had an INR test (81–82% vs 14–21%), and days with INR testing were the main driver for external AF-related care for warfarin patients.

Conclusion

Among NVAF patients treated with OACs, NOACs were associated with a longer time at home and time at home without external AF-related care compared to warfarin. These results can help inform healthcare providers and patients regarding the impact of NOAC treatment in NVAF patients.

Funding Acknowledgement

Type of funding sources: Private company. Main funding source(s): Bristol-Myers Squibb Company and Pfizer Inc.

Effectiveness and safety of non-vitamin K antagonist oral anticoagulants among nonvalvular atrial fibrillation patients with prior bleeding events

Background

Among non-valvular atrial fibrillation (NVAF) patients with a history of bleeding, there is a reluctance to use oral anticoagulants (OACs) due to concerns about the risk of bleeding associated with OACs. However, lack of OAC treatments for NVAF patients is associated with a higher risk of stroke and mortality. Non-vitamin K antagonist OAC (NOACs) have been approved for the prevention of stroke in NVAF patients. There are limited data comparing the risk of stroke/systemic embolism (S/SE) and major bleeding (MB) between patients prescribed NOACs and with a history of bleeding.

Purpose

This study used multiple United States data sources to evaluate the risk of S/SE and MB among NVAF patients with prior bleeding events who were prescribed NOACs.

Methods

This retrospective observational study used data from CMS Medicare and four commercial databases–covering &gt;180 million beneficiaries. The study selected adult NVAF patients who were prescribed apixaban, dabigatran, or rivaroxaban (01JAN2013–30JUN2019) and had a prior bleeding event which was defined as a hospitalization with a bleeding diagnosis (intracranial hemorrhage [ICH], gastrointestinal [GI] bleeding, or other bleeding sites) prior to or during the index treatment episode. After 1:1 propensity-score-matched (PSM) in each database between NOACs (apixaban-dabigatran, apixaban-rivaroxaban, and dabigatran-rivaroxaban), the resulting patient records were pooled. S/SE and MB (identified by inpatient claims) were captured during the follow-up period, which was defined as the time between the day after the index treatment date and treatment discontinuation or switch, death, end of study period, or end of medical and pharmacy enrollment. Hazard ratios of S/SE and MB were calculated using Cox proportional hazards models.

Results

Of the overall NVAF population treated with NOACs, 6.2% had a prior bleeding event (ICH: 13.5%; GI: 61.8%; Other: 24.6%). After PSM, a total of 11,106 apixaban-dabigatran, 30,665 apixaban-rivaroxaban, and 11,148 dabigatran-rivaroxaban pairs were matched. Apixaban was associated with a lower risk of S/SE compared to dabigatran and rivaroxaban, and dabigatran was associated with a similar risk of S/SE compared to rivaroxaban. Apixaban was associated with a lower risk of MB compared to dabigatran and rivaroxaban, and dabigatran was associated with a lower risk of MB compared to rivaroxaban (Figure).

Conclusions

In this subgroup of NVAF patients with a history of bleeding, apixaban was associated with a lower risk of S/SE and MB compared to dabigatran and rivaroxaban. Dabigatran was associated with a lower risk of MB compared to rivaroxaban. These results are informative for understanding the impact of NOAC treatment in NVAF patients with prior bleeding events.

Funding Acknowledgement

Type of funding sources: Private company. Main funding source(s): Bristol-Myers Squibb Company and Pfizer, Inc.

Effectiveness and Safety of Oral Anticoagulants Among Nonvalvular Atrial Fibrillation Patients With Active Cancer

Background

Patients with cancer are more likely to develop nonvalvular atrial fibrillation (NVAF). Currently there are no definitive clinical trials or treatment guidelines for NVAF patients with concurrent cancer.

Objectives

This subgroup analysis of the ARISTOPHANES study compared the risk of stroke/systemic embolism (stroke/SE) and major bleeding (MB) among NVAF patients with active cancer who were prescribed non–vitamin K antagonist oral anticoagulants (NOACs) or warfarin.

Methods

A retrospective observational study was conducted in NVAF patients with active cancer who newly initiated apixaban, dabigatran, rivaroxaban, or warfarin from January 1, 2013, through September 30, 2015, with the use of Medicare and 4 U.S. commercial claims databases. Cox models were used to estimate the risk of stroke/SE and MB in the pooled propensity score–matched cohorts.

Results

A total of 40,271 patients were included, with main cancer types of prostate (29%), female breast (17%), genitourinary (14%), and lung (13%). Compared with warfarin, apixaban was associated with a lower risk of stroke/SE (hazard ratio [HR]: 0.59; 95% confidence interval [CI]: 0.45-0.78) and MB (HR: 0.58; 95% CI: 0.50-0.68); dabigatran and rivaroxaban had similar risks of stroke/SE (dabigatran: HR: 0.88 [95% CI: 0.54-1.41]; rivaroxaban: HR: 0.82 [95% CI: 0.62-1.08]) and MB (dabigatran: HR: 0.76 [95% CI: 0.57-1.01]; rivaroxaban: HR: 0.95 [95% CI: 0.85-1.06]). Risks of stroke/SE and MB varied among NOAC-NOAC comparisons, while consistent treatment effects were seen for all treatment comparisons across key cancer types.

Conclusions

Among this cohort of NVAF patients with active cancer, the risk of stroke/SE and MB varied among oral anticoagulants and were consistent across cancer types.

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.

Real-world persistence to direct oral anticoagulants in patients with atrial fibrillation: a systematic review and network meta-analysis

OBJECTIVE

To conduct a systematic review and network meta-analysis of real-world evidence comparing adherence, persistence, cost, and utilization between oral anticoagulant (OAC) in non-valvular atrial fibrillation (NVAF) patients.

METHODS

A systematic search of MEDLINE and Embase (inception-July 2019) was conducted for published observational cohort studies comparing outcomes between ≥2 OACs. A network meta-analysis was performed to estimate odds ratios for non-persistence using a random-effects model.

RESULTS

There were 80 studies evaluating the outcomes of interest. However, due to a paucity in adherence studies and heterogeneity in adherence, cost, and utilization definitions, persistence was the focus of this network meta-analysis. There were 36 studies evaluating non-persistence in 395,593 participants, 24 of which used 3 gap definitions (30-, 60-, and 90-days); 18 unique studies evaluating non-persistence at 12 months were included in the network meta-analysis. Using 30- and 90-day gaps, all NOACs, when compared with VKAs, had lower odds of non-persistence (30-day OR (95%CI): apixaban: 0.63 (0.58, 0.69); rivaroxaban: 0.69 (0.62, 0.76); dabigatran: 0.89 (0.82, 0.97); 90-day OR (95%CI): apixaban: 0.33 (0.22, 0.47); rivaroxaban: 0.47 (0.36, 0.61); dabigatran 0.61 (0.44, 0.85)). When using a 60-day gap, dabigatran had higher odds of non-persistence vs VKAs (OR: 1.35; 95%CI: 1.12, 1.61), but there were no significant differences for apixaban and rivaroxaban. Apixaban had the lowest probability of non-persistence across the 3-gap definitions (95.7% with 30-day gap, 76.9% with 60-day gap, 98.4% with 90-day gap).

CONCLUSIONS

The current findings, despite multiple limitations, can raise awareness and understanding of real-world persistence associated with OAC therapy in NVAF patients.

Use of Non-Vitamin K Antagonist Oral Anticoagulants Among Patients with Nonvalvular Atrial Fibrillation and Multimorbidity

Introduction

Non-valvular atrial fibrillation (NVAF) is often accompanied by multiple comorbid conditions, which increase the associated risks and complexity of patient management. This study evaluated the risk of stroke/systemic embolism (SE) and major bleeding (MB) among multimorbid patients with NVAF who were prescribed non-vitamin K antagonist oral anticoagulants (NOACs) or warfarin.

Methods

A retrospective study of patients with NVAF and high multimorbidity who initiated apixaban, dabigatran, rivaroxaban, or warfarin from 1 January 2013 to 30 September 2015 was conducted using five insurance claims databases. Multimorbidity was defined as six or more comorbid conditions, and 1:1 propensity score matching (PSM) was conducted between the NOAC-warfarin and NOAC-NOAC cohorts. Cox proportional hazard models were used to evaluate the hazard ratios of stroke/SE and MB.

Results

Of the NVAF population (n = 466,991), 33.4% (n = 155,959) had multimorbidity, including 36,921 apixaban, 10,248 dabigatran, 45,509 rivaroxaban, and 63,281 warfarin patients. Compared to warfarin, apixaban and rivaroxaban were associated with a lower risk of stroke/SE (hazard ratio [HR] 0.63, 95% CI 0.54–0.74; HR 0.70, 95% CI 0.64–0.77, respectively). Apixaban and dabigatran were associated with a lower risk of MB (HR 0.61, 95% CI 0.56–0.67; HR 0.75, 95% CI 0.66–0.86, respectively) and rivaroxaban was associated with a higher risk of MB (HR 1.06, 95% CI 1.01–1.12) compared to warfarin.

Conclusions

Among patients with NVAF and six or more comorbid conditions, NOACs were associated with varying risk of stroke/SE and MB compared to warfarin and to each other. Rather than a “one drug fits all” approach, our results may be useful for appropriate OAC treatment for multimorbid patients.

Supplementary Information

The online version contains supplementary material available at 10.1007/s12325-021-01724-8.

Burden of major gastrointestinal bleeding among oral anticoagulant-treated non-valvular atrial fibrillation patients

BACKGROUND

Gastrointestinal (GI) bleeding is the most common type of major bleeding associated with oral anticoagulant (OAC) treatment. Patients with major bleeding are at an increased risk of a stroke if an OAC is not reinitiated.

METHODS

Non-valvular atrial fibrillation (NVAF) patients initiating OACs were identified from the Centers for Medicare and Medicaid Services (CMS) Medicare data and four US commercial claims databases. Patients who had a major GI bleeding event (hospitalization with primary diagnosis of GI bleeding) while on an OAC were selected. A control cohort of patients without a major GI bleed during OAC treatment was matched to major GI bleeding patients using propensity scores. Stroke/systemic embolism (SE), major bleeding, and mortality (in the CMS population) were examined using Cox proportional hazards models with robust sandwich estimates.

RESULTS

A total of 15,888 patients with major GI bleeding and 833,052 patients without major GI bleeding were included in the study. Within 90 days of the major GI bleed, 58% of patients discontinued the initial OAC treatment. Patients with a major GI bleed had a higher risk of stroke/SE [hazard ratio (HR): 1.57, 95% confidence interval (CI): 1.42-1.74], major bleeding (HR: 2.79, 95% CI: 2.64-2.95), and all-cause mortality (HR: 1.29, 95% CI: 1.23-1.36) than patients without a major GI bleed.

CONCLUSION

Patients with a major GI bleed on OAC had a high rate of OAC discontinuation and significantly higher risk of stroke/SE, major bleeding, and mortality after hospital discharge than those without. Effective management strategies are needed for patients with risk factors for major GI bleeding.

Oral anticoagulants for nonvalvular atrial fibrillation in frail elderly patients: insights from the ARISTOPHANES study

BACKGROUND

Patient frailty amongst patients with nonvalvular atrial fibrillation (NVAF) is associated with adverse health outcomes and increased risk of mortality. Additional evidence is needed to evaluate effective and safe NVAF treatment in this patient population.

OBJECTIVES

This subgroup analysis of the ARISTOPHANES study compared the risk of stroke/systemic embolism (S/SE) and major bleeding (MB) amongst frail NVAF patients prescribed nonvitamin K antagonist oral anticoagulants (NOACs) or warfarin.

METHODS

This comparative retrospective observational study of frail, older NVAF patients who initiated apixaban, dabigatran, rivaroxaban or warfarin from 01JAN2013-30SEP2015 was conducted using Medicare and 3 US commercial claims databases. To compare each drug, 6 propensity score-matched (PSM) cohorts were created. Patient cohorts were pooled from 4 databases after PSM. Cox models were used to estimate hazard ratios (HR) of S/SE and MB.

RESULTS

Amongst NVAF patients, 34% (N = 150 487) met frailty criteria. Apixaban and rivaroxaban were associated with a lower risk of S/SE vs warfarin (apixaban: HR: 0.61, 95% CI: 0.55-0.69; rivaroxaban: HR: 0.79, 95% CI: 0.72-0.87). For MB, apixaban (HR: 0.62, 95% CI: 0.57-0.66) and dabigatran (HR: 0.79, 95% CI: 0.70-0.89) were associated with a lower risk and rivaroxaban (HR: 1.14, 95% CI: 1.08-1.21) was associated with a higher risk vs warfarin.

CONCLUSION

Amongst this cohort of frail NVAF patients, NOACs were associated with varying rates of stroke/SE and MB compared with warfarin. Due to the lack of real-world data regarding OAC treatment in frail patients, these results may inform clinical practice in the treatment of this patient population.

Utilization of anticoagulants and predictors of treatment among hospitalized patients with atrial fibrillation in the USA

OBJECTIVE

To evaluate utilization of anticoagulants (ACs) and the predictors of treatment of patients with a diagnosis of atrial fibrillation (AF) during a hospital stay in the USA.

METHODS

Patients (≥18 years of age) who had a primary or secondary discharge diagnosis code of AF during a hospitalization (without a diagnosis of venous thromboembolism) were identified from the Premier Hospital database (1 January 2016-30 September 2017). AC treatments were examined during hospitalizations to assign AF patients into 3 study cohorts: those who received an oral AC (OAC), those who received parenteral AC only, and those who did not receive AC therapy. Multivariable logistic regression analyses were carried out to evaluate potential predictors of receiving parenteral AC only vs. OAC therapy, no AC therapy vs. OAC therapy, as well as the specific OAC drug choices.

RESULTS

Of the patients hospitalized with an AF diagnosis (n = 482,729; mean age: 74.7 years; 46.8% female; 82.9% White; 79.4% with Medicare), 42.6% received OAC therapy (most commonly, warfarin or apixaban), 35.3% parenteral AC only, and 22.2% no AC therapy. A key predictor of not receiving OAC therapy was having an AF diagnosis in the second position (applicable to 87.4% of study population). Greater comorbidity level and prior baseline bleeding were strong predictors of receiving parenteral AC only or not receiving any AC therapy vs. receiving OAC therapy. Predictors of receiving warfarin vs. apixaban included higher stroke risk and prior baseline bleeding.

LIMITATIONS

OAC utilization may have been underestimated since outpatient OAC utilization was not included in the analysis.

CONCLUSIONS

A substantial portion of hospitalized AF patients did not receive any AC therapy, particularly those patients with an AF diagnosis in the second position on hospital records. The predictors of inpatient AC treatment that were identified may be helpful in the clinical decision-making process for patients who are hospitalized with AF.

Effectiveness and Safety of Oral Anticoagulants Among Non-Valvular Atrial FibrillationPatients with Polypharmacy

AIMS

Polypharmacy is prevalent among non-valvular atrial fibrillation (NVAF) patients and presents a potential issue for the effective management of NVAF. This study compared the risk of stroke/systemic embolism (SE) and major bleeding (MB) among NVAF patients with polypharmacy newly prescribed oral anticoagulants (OACs).

METHODS AND RESULTS

A retrospective study of NVAF patients with polypharmacy who initiated OACs from 01JAN2013-30SEP2015 was conducted using US CMS Medicare and four commercial databases. Polypharmacy was defined as ≥ 6 concomitant medications on the index date. Propensity score matching was conducted to compare non-Vitamin K antagonists OACs (NOACs) to warfarin as well as between NOACs. Cox proportional hazard models were used to evaluate the risk of stroke/SE and MB. A total of 188,893 patients with polypharmacy were included, with an average of 8 concomitant medications (IQR 6-9). Compared to warfarin, apixaban (HR: 0.59, 95% CI: 0.52-0.68) and rivaroxaban (HR: 0.75, 95% CI: 0.69-0.83) were associated with a lower risk of stroke/SE. Apixaban (HR: 0.57, 95% CI: 0.54-0.61) and dabigatran (HR: 0.76, 95% CI: 0.66-0.88) were associated with a decreased risk of MB compared with warfarin. Compared with dabigatran and rivaroxaban, apixaban was associated with a lower risk of stroke/SE and MB. Dabigatran was associated with lower risk of MB compared with rivaroxaban.

CONCLUSIONS

In this observational study of anticoagulated NVAF patients with polypharmacy, effectiveness and safety profiles are more favorable for NOACs vs warfarin. Our observations are hypothesis generating and may help inform future clinical trials regarding appropriate OAC treatment selection in polypharmacy patients.

Comparison of readmissions among hospitalized nonvalvular atrial fibrillation patients treated with oral anticoagulants in the United States

Objectives

To compare the risks of 1-month all-cause, major bleeding (MB)-related and stroke-related readmissions and the associated hospital resource use and costs among patients previously hospitalized for nonvalvular atrial fibrillation (NVAF) and treated with warfarin, rivaroxaban, and dabigatran vs apixaban.

Methods

Adult patients hospitalized with NVAF (any discharge diagnosis position) who received apixaban, warfarin, rivaroxaban, or dabigatran during hospitalization were identified from the Premier database (1 January 2013–30 June 2017) and grouped into respective cohorts. Propensity score matching was used to generate cohorts with similar characteristics. In regression analyses the risk of readmissions that occurred within 1 month of discharge were evaluated and the associated length of stay (LOS) and costs compared.

Results

NVAF patients treated with warfarin vs apixaban had significantly greater risk of all-cause (odds ratio [OR] = 1.05; confidence interval [CI] = 1.02–1.08; p < .001), MB-related (OR: 1.28; CI: 1.16–1.42; p < .001), and stroke-related (OR: 1.33; CI: 1.11–1.58; p = .002) readmissions; for all readmission categories, average LOS was significantly longer and costs significantly higher for warfarin treated patients. NVAF patients treated with rivaroxaban versus apixaban had significantly greater risk of all-cause (OR: 1.06; CI: 1.02–1.09; p = .001) and MB-related (OR = 1.62; CI = 1.44–1.83; p < .001) readmissions, but not stroke-related readmission; for MB-related readmissions average LOS and costs were higher for rivaroxaban treated patients. Significant differences in risks of all-cause, MB-related, and stroke-related readmissions were not observed between the apixaban and dabigatran cohorts.

Conclusion

In this retrospective real-world analysis of NVAF patients, apixaban treatment was associated with better clinical outcomes than warfarin or rivaroxaban and lower hospital resource burden.

Comparison of inpatient admission rates of patients treated with apixaban vs. warfarin for venous thromboembolism in the emergency department

Objectives: This study evaluated inpatient admission status, hospitalization length of stay (LOS), hospital costs, and readmissions of patients who were diagnosed with venous thromboembolism (VTE) and treated with apixaban or warfarin in the emergency department (ED).Methods: Patients (≥18 years) with an ED visit with a primary discharge diagnosis code of VTE were identified from the Premier Hospital database (8/1/2014-5/31/2018). Patients who received apixaban or warfarin during the ED visit were selected and grouped into two treatment cohorts. Outcomes of ED disposition (discharged or admitted to the inpatient setting), hospital LOS, hospital cost of index event, and rate of 1-month readmissions were compared for the study cohorts.Results: Of the overall study population, 30.5% (n = 12,174; mean age: 59.7 years) received apixaban and 69.5% (n = 27,767; mean age: 59.3 years) received warfarin for VTE in the ED. After adjusting for patient and hospital characteristics, the regression analysis showed that apixaban was associated with a significantly lower likelihood of admission to the inpatient setting vs. warfarin (Odds Ratio [OR]: 0.12, 95% Confidence Interval [CI]: 0.12 to 0.13; p < 0.001). Correspondingly, mean index hospital LOS was 1.42 days shorter (95% CI: -1.47 to -1.36; p < 0.001) and mean index event hospital cost per patient was significantly lower by $4,276 ($3,732 [95% CI: $3,565 to $3,907] vs. $8,008 [95% CI: $7,676 to $8,355]; p < 0.001). Also, the likelihood of all-cause 1-month readmission was significantly lower for patients treated with apixaban vs. warfarin (OR: 0.85, 95% CI: 0.79 to 0.92; p < 0.001).Conclusions: In the real-world setting, VTE patients with an ED visit who were treated with apixaban vs. warfarin had a lower likelihood of being admitted to the inpatient setting, which was reflected in shorter average LOS and lower average index event cost. Additionally, the risk of 1-month readmission was also lower for patients treated with apixaban vs. warfarin.

Contemporary NSTEMI management: the role of the hospitalist

Non-ST-segment elevation myocardial infarction (NSTEMI) is defined as elevated cardiac biomarkers of necrosis in the absence of persistent ST-segment elevation in the setting of anginal symptoms or other acute event. It carries a poorer prognosis than most ST-segment elevation events, owing to the typical comorbidity burden of the older NSTEMI patients as well as diverse etiologies that add complexity to therapeutic decision-making. It may result from an acute atherothrombotic event ('Type 1') or as the result of other causes of mismatch of myocardial oxygen supply and demand ('Type 2'). Regardless of type and other clinical factors, the hospital medicine specialist is increasingly responsible for managing or coordinating the care of these patients. Following published guidelines for risk stratification and basing anti-anginal, anticoagulant, antiplatelet, other pharmacologic therapies, and overall management approach on that individualized patient risk assessment can be expected to result in better short- and long-term clinical outcomes, including near-term readmission and recurrent events. We present here a review of the evidence basis and expert commentary to assist the hospitalist in achieving those improved outcomes in NSTEMI. Given that the Society for Hospital Medicine cites care of patients with acute coronary syndrome as a core competency for hospitalists, it is essential that those specialists stay current on optimal NSTEMI care.Abbreviations: ACC: American college of cardiology; ACCOAST: comparison of prasugrel at the time of diagnosis in patients with non-ST elevation myocardial infarction; ACS: acute coronary syndrome; ADP: adenosine diphosphate; AHA: American heart association; ARB: angiotensin II receptor blocker; ASA: acetylsalicylic acid; CABG: coronary artery bypass graft: CAD: coronary artery disease; CCTA: coronary computed tomography angiography; cTn: cardiac troponin; CRUSADE: can rapid risk stratification of unstable angina patients suppress adverse outcomes with early implementation of the ACC/AHA guidelines; CURE: clopidogrel in unstable angina to prevent recurrent events; CURRENT: OASIS-7 clopidogrel and aspirin optimal dose usage to reduce recurrent events-seventh organization to assess strategies in ischemic syndromes; ECG: electrocardiogram; ED: emergency department; ESRD: endstage renal disease; ESC: European society of cardiology; FDA: food and drug administration; GRACE: global registry of acute coronary events; LVEF: left ventricular ejection fraction; MACE: major adverse cardiac event; MI: myocardial infarction; MVO₂: myocardial oxygen demand; NSTEMI: non-ST-segment-elevation myocardial infarction; NTG: Nitroglycerin; PCI: percutaneous coronary intervention; plato: platelet inhibition and patient outcomes; PPI: proton pump inhibitor; PURSUIT: platelet glycoprotein IIb/IIIa in unstable angina: Receptor Suppression Using Integrilin Therapy; RAAS: Renin-Angiotensin-Aldosterone System; SHM: society of hospital medicine; STEMI: ST-segment-elevation myocardial infarction; TIMI: Thrombolysis in Myocardial Infarction; TRITON-TIMI:trial to assess improvement in therapeutic outcomes by optimizing platelet inhibition with prasugrel-thrombolysis in myocardial infarction.

Frequency of hospital readmissions for venous thromboembolism and associated hospital costs and length of stay among acute medically ill patients in the US

Objectives: This study evaluated the frequency of hospital readmissions for venous thromboembolism (VTE) and the associated costs and length of stay (LOS) among acute medically ill patients in the US using a real-world claims database analysis. Methods: Patients (≥40 years of age) at risk of VTE due to hospitalization for acute medical illnesses, based on primary hospital discharge diagnosis codes, were identified from the MarketScan databases between July 1, 2011 and March 31, 2015. Patients were required to have continuous insurance enrollment in the 6 months prior to initial (index) hospitalizations (baseline period) and in the 6 months after hospital discharge (follow-up period). The proportions of patients with VTE-related (diagnosis at any position) and VTE as primary diagnosis hospital readmissions during the follow-up period were evaluated. The associated costs and LOS for such readmissions were also determined, as well as time to VTE-related readmissions. Results: Of the study population (n = 12,785; mean age = 68.3 years), most were hospitalized primarily for infectious diseases (35.2%), followed by respiratory diseases (27.9%), cancer (15.7%), heart failure (11.8%), ischemic stroke (8.1%), and rheumatic diseases (1.4%). Of the overall study population, 2.1% (n = 268) had a VTE-related hospital readmission in the 6 months following discharge of their index hospitalization, of which 36.6% (n = 98) were for a primary diagnosis of VTE. Approximately 25.4% of the VTE-related hospital readmissions occurred within the first 30 days of discharge and 58.2% within 90 days. The mean cost for a hospital readmission with a primary diagnosis of VTE was $18,681 (mean LOS = 5.0 days); for readmissions with a primary diagnosis of DVT and PE, mean costs were $14,719 and $23,305, respectively. Conclusions: Among this study population of patients hospitalized for acute medical illnesses, some experienced a VTE event requiring re-hospitalization, with 25% occurring within the first 30 days after hospital discharge.

Effectiveness and Safety of Oral Anticoagulants Among Nonvalvular Atrial Fibrillation Patients

Supplemental Digital Content is available in the text.

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.

P4794Comparative effectiveness and safety of non-VKA oral anticoagulants versus warfarin in non-valvular atrial fibrillation patients with differential treatment duration: an ARISTOPHANES study analysis

Background

The ARISTOPHANES (Anticoagulants for Reduction In STroke: Observational Pooled analysis on Health outcomes ANd Experience of patientS) study showed that non-vitamin K antagonist oral anticoagulants (NOACs) were associated with lower risks of stroke/systemic embolism (S/SE) and variable comparative risks of major bleeding (MB) versus warfarin.

Purpose

To assess long-term use of non-VKA oral anticoagulants (NOACs) vs. warfarin in

ARISTOPHANES by evaluating the risk of S/SE and MB among non-valvular atrial fibrillation (NVAF) patients by duration of treatment (<1 and ≥1 year).

Methods

In the ARISTOPHANES study, NVAF patients initiating apixaban, dabigatran, rivaroxaban, or warfarin from 01/01/2013–09/30/2015 were identified from the CMS Medicare data and four US commercial claims databases, covering >180 million beneficiaries annually (∼56% of US population). After 1:1 propensity score matching (PSM) in each database between NOACs and warfarin (apixaban-warfarin, dabigatran-warfarin, and rivaroxaban-warfarin), the resulting patient records were pooled. Treatment duration was defined as time between the day after the treatment index date and discontinuation (30 days after a 30-day gap in the prescription), treatment switch, death, end of study period, or end of continuous medical and pharmacy enrollment, whichever occurred first. Matched patients with observed treatment duration <1 or ≥1 year were separately examined. Cox models were used to estimate hazard ratios of S/SE and MB (identified by inpatient claims) during observed treatment duration.

Results

The mean treatment duration for patients with shorter (<1 year) vs longer (≥1 year) duration was 4–5 months vs 18–21 months across the three matched cohorts. All the matched baseline variables remained balanced. The incidence rates of S/SE and MB and the proportion of patients with treatment discontinuation were higher in patients with shorter treatment duration. Regardless of treatment duration, apixaban patients had a lower risk of S/SE and MB versus warfarin; dabigatran patients had a lower risk of MB versus warfarin; and rivaroxaban patients had a lower risk of S/SE versus warfarin. Compared to warfarin patients, dabigatran patients with treatment duration <1 year had a similar risk of S/SE, while those with treatment duration ≥1 year had lower S/SE risk; rivaroxaban patients with treatment duration <1 year had a higher risk of MB, while those with treatment duration ≥1 year had similar MB risk.

Conclusions

Among NVAF patients with duration of treatment <1 and ≥1 year in the ARISTOPHANES study, apixaban and rivaroxaban were associated with lower risk of S/SE, while apixaban and dabigatran were associated with lower risk of MB, compared to warfarin. These findings indicate varying long-term effectiveness and safety outcomes between NOACs and warfarin.

Acknowledgement/Funding

This study was funded by Bristol-Myers Squibb and Pfizer Inc.

P4768Comparative effectiveness and safety between non-VKA oral anticoagulants in non-valvular atrial fibrillation patients with differential duration of treatment: an analysis of the ARISTOPHANES study

Background

The ARISTOPHANES (Anticoagulants for Reduction In STroke: Observational Pooled analysis on Health outcomes ANd Experience of patientS) study showed that apixaban was associated with lower risks of stroke/systemic embolism (S/SE) and major bleeding (MB) versus dabigatran and rivaroxaban; dabigatran was associated with similar risk of S/SE and lower risk of MB compared to rivaroxaban.

Purpose

To assess long-term use of non-VKA oral anticoagulants (NOACs) in ARISTOPHANES by evaluating the risk of S/SE and MB among non-valvular atrial fibrillation (NVAF) patients receiving different NOACs by duration of treatment (<1 and ≥1 year).

Methods

In the ARISTOPHANES study, NVAF patients initiating apixaban, dabigatran, and rivaroxaban from 01/01/2013–09/30/2015 were identified from the CMS Medicare data and four US commercial claims databases, covering >180 million beneficiaries annually (∼56% of US population). After 1:1 propensity score matching (PSM) in each database between NOACs (apixaban-dabigatran, apixaban-dabigatran, and dabigatran-rivaroxaban), the resulting patient records were pooled. Treatment duration was defined as time between the day after the index treatment date and discontinuation (defined using a 30-day gap in the prescription), treatment switch, death, end of study period, or end of continuous medical and pharmacy enrollment, whichever occurred first. Matched patients with observed treatment duration <1 or ≥1 year were separately examined. Cox models were used to estimate hazard ratios of S/SE and MB (identified by inpatient claims) during observed treatment duration. S/SE included ischemic stroke, hemorrhagic stroke, and SE; MB included gastrointestinal (GI) bleeding, intracranial hemorrhage (ICH), and other MB.

Results

The mean treatment duration for patients with shorter (<1 year) vs longer (≥1 year) duration was ∼4 months vs 18–21 months across the three matched cohorts. All the matched baseline variables remained balanced. The incidence rates of S/SE and MB and the proportion of patients with treatment discontinuation were higher in patients with shorter treatment duration. Regardless of treatment duration, apixaban and dabigatran had a lower risk of MB versus rivaroxaban; and dabigatran had a similar risk of S/SE versus rivaroxaban. Compared to dabigatran patients, apixaban patients with treatment duration <1 year had a lower risk of S/SE and MB, while those with treatment duration ≥1 year had similar S/SE and MB risk. Compared to rivaroxaban patients, apixaban patients with treatment duration <1 year had a lower risk of S/SE, while those with treatment duration ≥1 year had similar S/SE risk.

Conclusions

Across NVAF patients with duration of treatment <1 and ≥1 year in the ARISTOPHANES study, both apixaban and dabigatran were associated with a lower risk of MB compared to rivaroxaban. These findings indicate varying long-term safety outcomes among different NOACs.

Acknowledgement/Funding

This study was funded by Bristol-Myers Squibb and Pfizer Inc.

Budget impact analysis of betrixaban for venous thromboembolism prophylaxis in nonsurgical patients with acute medical illness in the United Kingdom

OBJECTIVES

Venous thromboembolism (VTE) incurs substantial costs to the UK National Health Service (NHS). Betrixaban is approved in the US for VTE prophylaxis with a recommended 35-42 days of treatment. This analysis modeled the budget impact of introducing betrixaban for extended-duration VTE prophylaxis in nonsurgical patients with acute medical illness at risk of VTE in the UK, where it is not yet licensed.

METHODS

The 5-year budget impact of introducing betrixaban into current prophylaxis (low molecular weight heparin and fondaparinux) was estimated for the UK NHS. The Phase 3 APEX study provided primary event (VTE, myocardial infarction, ischemic stroke, and death; all-cause or VTE-related) and treatment complications data. Literature informed risk of recurrent events and long-term complications, population, market share, and costs for treatment and management of events. Network meta-analyses informed symptomatic DVT, pulmonary embolism and VTE-related death rates in fondaparinux patients. Deterministic sensitivity analyses explored uncertainty.

RESULTS

Introducing betrixaban accrued savings of £1,290,000-£23,000,000 in years 1-5. Savings were from reduced primary VTE events, which reduced recurrent events and future complications. All sensitivity analyses showed savings.

CONCLUSION

Introducing extended-duration VTE prophylaxis with betrixaban in the UK would accrue substantial savings annually over the next 5 years compared to current prophylaxis. Clinical trial registration: www.clinicaltrials.gov identifier is NCT01583218.

Comparisons between Oral Anticoagulants among Older Nonvalvular Atrial Fibrillation Patients

OBJECTIVES

Older adult patients are underrepresented in clinical trials comparing non–vitamin K antagonist oral anticoagulants (NOACs) and warfarin. This subgroup analysis of the ARISTOPHANES study used multiple data sources to compare the risk of stroke/systemic embolism (SE) and major bleeding (MB) among very old patients with nonvalvular atrial fibrillation (NVAF) prescribed NOACs or warfarin.

DESIGN

Retrospective observational study.

SETTING

The Centers for Medicare & Medicaid Services and three US commercial claims databases.

PARTICIPANTS

A total of 88 582 very old (aged ≥80 y) NVAF patients newly initiating apixaban, dabigatran, rivaroxaban, or warfarin from January 1, 2013, to September 30, 2015.

MEASUREMENTS

In each database, six 1:1 propensity score matched (PSM) cohorts were created for each drug comparison. Patient cohorts were pooled from all four databases after PSM. Cox proportional hazards models were used to estimate hazard ratios (HRs) of stroke/SE and MB.

RESULTS

The patients in the six matched cohorts had a mean follow‐up time of 7 to 9 months. Compared with warfarin, apixaban (HR = .58; 95% confidence interval [CI] = .49‐.69), dabigatran (HR = .77; 95% CI = .60‐.99), and rivaroxaban (HR = .74; 95% CI = .65‐.85) were associated with lower risks of stroke/SE. For MB, apixaban (HR = .60; 95% CI = .54‐.67) was associated with a lower risk; dabigatran (HR = .92; 95% CI = .78‐1.07) was associated with a similar risk, and rivaroxaban (HR = 1.16; 95% CI = 1.07‐1.24) was associated with a higher risk compared with warfarin. Apixaban was associated with a lower risk of stroke/SE and MB compared with dabigatran (stroke/SE: HR = .65; 95% CI = .47‐.89; MB: HR = .60; 95% CI = .49‐.73) and rivaroxaban (stroke/SE: HR = .72; 95% CI = .59‐.86; MB: HR = .50; 95% CI = .45‐.55). Dabigatran was associated with a lower risk of MB (HR = .77; 95% CI = .67‐.90) compared with rivaroxaban.

CONCLUSION

Among very old NVAF patients, NOACs were associated with lower rates of stroke/SE and varying rates of MB compared with warfarin. J Am Geriatr Soc 67:1662–1671, 2019

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.

Abstract WP385: Burden of Rehospitalizations for Venous Thromboembolism Among Patients With Ischemic Stroke

Introduction: Patients hospitalized for ischemic stroke are at risk for venous thromboembolism (VTE) that remains high after discharge. Without adequate VTE prophylaxis covering the entire risk period, including after discharge, patients are at risk of VTE-related rehospitalization. The goal of this study was to analyze the frequency and associated cost of VTE-related readmissions among patients with ischemic stroke in the US.

Methods: Patients hospitalized for ischemic stroke, based on the primary hospital discharge diagnosis codes, were identified from the MarketScan databases (7/1/2011 to 3/31/2015). Eligible patients were ≥40 y and had continuous insurance enrollment ≤6 mo prior to initial (index) hospitalizations (baseline period) and >6 mo after discharge (follow-up period). The study endpoints were: the proportion of patients readmitted for the primary VTE or any position VTE (VTE-related) during the follow-up period, and the associated resources and costs of readmissions.

Results: For this retrospective analysis, data from 1,030 patients hospitalized for ischemic stroke were available; mean age: 71.6 y (66.2% were ≥65 y), 52.1% female, mean Charlson Comorbidity Index score: 3.3. For index hospitalization, 55.3% of patients were hospitalized for 1-3 d, and 33.3% for 4-7 d. During index hospitalization, 1.3% of patients had a VTE. In the 6 months following discharge, 1.4% had a VTE-related hospital readmission, of which 50% were for a primary diagnosis of VTE. Over one-third (35.7%) of the VTE-related readmissions occurred ≤30 d of discharge. For VTE-related readmissions, mean length of hospital stay (LOS) was 14.9 d and the mean total cost for a hospital readmission was $39,692. For primary VTE readmissions, the mean LOS was 4.9 d and the mean total cost of a readmission was $12,384.

Conclusions: In this real-world study, 1.4% of patients hospitalized for ischemic stroke had a VTE-related hospital readmission, and of these, one-third were readmitted ≤30 d of discharge. The economic burden of VTE-related or primary VTE hospital readmissions was substantial. Improvement in VTE prophylaxis across the inpatient/outpatient care continuum may reduce the clinical and economic burden of VTE and associated rehospitalizations in these patients.

Hospital Resource Utilization and Costs Associated With Warfarin Versus Apixaban Treatment Among Patients Hospitalized for Venous Thromboembolism in the United States

A real-world US database analysis was conducted to evaluate the hospital resource utilization and costs of patients hospitalized for venous thromboembolism (VTE) treated with warfarin versus apixaban. Additionally, 1-month readmissions were evaluated. Of 28 612 patients with VTE identified from the Premier Hospital database (August 2014-May 2016), 91% (N = 26 088) received warfarin and 9% (N = 2524) received apixaban. Outcomes were assessed after controlling for key patient/hospital characteristics. For index hospitalizations, the average length of stay (LOS) was longer (3.8 vs 3.1 days, P < .001; difference: 0.7 days) and mean hospitalization cost higher (US$3224 vs US$2,740, P < .001; difference: US$484) for warfarin versus apixaban-treated patients. During the 1-month follow-up period, warfarin treatment was associated with a greater risk of all-cause readmission (odds ratio [OR]: 1.27; 95% confidence interval [CI]: 1.09-1.48, P = .003), major bleeding (MB)-related readmission (OR: 2.10; 95% CI: 1.03-4.27, P = .04), and any bleeding-related readmission (OR: 1.67; 95% CI: 1.09-2.56, P = .02) versus apixaban. The results of this real-world analysis show that compared to warfarin, apixaban treatment was associated with shorter index hospital stays, lower index hospitalization costs, and reduced risk of MB-related readmissions among hospitalized patients with VTE.

Comparison of major bleeding risk in patients with non-valvular atrial fibrillation receiving direct oral anticoagulants in the real-world setting: a network meta-analysis

OBJECTIVE

To conduct a systematic literature review (SLR) and network meta-analysis (NMA) of real-world studies comparing major bleeding risk among patients with non-valvular atrial fibrillation (NVAF) on direct oral anticoagulants (DOACs) or warfarin.

METHODS

Systematic searches were conducted in MEDLINE and Embase for full-text articles published between January 1, 2003 and March 18, 2017. Eligible studies compared at least two of the following in a real-world setting: warfarin, apixaban, dabigatran, rivaroxaban, or edoxaban. A Bayesian NMA was conducted to estimate hazard ratios (HRs) for major bleeding using a random-effects model.

RESULTS

Eleven studies were included in the NMA. Nine studies included DOACs vs Warfarin comparisons, and four studies included DOACs vs DOACs comparisons (two studies included both comparisons). Median follow-up duration ranged from 2.6-31.2 months. No evidence was identified for edoxaban. Apixaban was associated with a significantly lower risk of major bleeding compared to other oral anticoagulants (warfarin HR = 0.58; 95% credible interval [CrI] = 0.48-0.69; dabigatran = 0.73; 0.61-0.87; rivaroxaban = 0.55; 0.46-0.66). Dabigatran was associated with a significantly lower risk than warfarin (0.79; 0.71-0.88) and rivaroxaban (0.76; 0.67-0.85), and rivaroxaban was not statistically different from warfarin (1.05; 0.91-1.19). Sensitivity analyses with standard dose and sponsorship showed consistent results.

CONCLUSION

DOACs were associated with lower or similar risk of major bleeding compared with warfarin in NVAF patients. Apixaban was associated with a significantly lower risk of major bleeding than other DOACs. Dabigatran was associated with a significantly lower risk of major bleeding compared to rivaroxaban and warfarin.

Incremental economic burden associated with major bleeding among atrial fibrillation patients treated with factor Xa inhibitors

OBJECTIVE

To evaluate healthcare resource use and costs incurred during, as well as following hospitalization for major bleeding (MB), among atrial fibrillation (AF) patients treated with factor Xa inhibitors Methods: Patients with an AF diagnosis and MB hospitalization (index event) were identified from the MarketScan Commercial and Medicare databases (January 1, 2011-December 31, 2014). Patients were required to have ≥1 prescription for rivaroxaban or apixaban within 3 months prior to MB hospitalization. AF patients treated with Xa inhibitors, but who did not have any diagnosis of MB during the study period were identified. Hospital resource use and costs were evaluated for index MB hospitalizations. Healthcare resource use and associated costs were also evaluated for up to 12 months and compared between AF patients with and without MB.

RESULTS

Of the overall patient population with AF treated with factor Xa inhibitors (n = 92,949), 3,081 (3.3%) were identified as patients with MB and 89,868 without MB. The mean hospital length of stay and hospital cost for index MB hospitalizations were 5.3 days and $28,059, respectively. Total all-cause healthcare costs were higher during the 12 months of follow-up for AF patients with MB vs without ($63,866 vs $37,916, p < .001). After adjusting for differences in patient characteristics, mean total healthcare costs were estimated at $58,169 for patients with MB vs $41,241 for patients without MB.

LIMITATIONS

Since this was an observational study using a claims database analysis, a causal relationship between factor Xa inhibitor treatment and MB events cannot be inferred from the results of this study.

CONCLUSION

In the real-world setting, the cost of initial hospitalizations for MB was substantial, and the incremental burden of total healthcare costs within 1 year following MB hospitalization was high. Approaches to better manage the continuum of care of AF patients with factor Xa inhibitor-associated MB may reduce the healthcare economic burden.

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.

Risk of major bleeding in patients with non-valvular atrial fibrillation treated with oral anticoagulants: a systematic review of real-world observational studies

OBJECTIVE

To conduct a systematic review of real-world (RWD) studies comparing the risk of major bleeding (MB) among patients with non-valvular atrial fibrillation (NVAF) on direct oral anticoagulants (DOACs) or warfarin.

METHODS

MEDLINE, Embase, NHS-EED, and EconLit were searched for RWD studies published between January 2003 and November 2016 comparing MB risk among DOACs and warfarin. Proceedings of clinical conferences from 2012 to 2016 were reviewed.

RESULTS

A total of 4218 citations were identified, 26 of which met eligibility criteria. Most studies were retrospective analyses of administrative claims databases and patient registries (n = 23 of 26); about half were based in the United States (n = 15). Apixaban showed a significantly lower risk of MB versus warfarin in all eight included studies. MB risk was either significantly lower (n = 9 of 16) or not significantly different (n = 7 of 16) between dabigatran and warfarin; there was no significant difference between rivaroxaban and warfarin in all seven included studies. The risk was significantly lower with apixaban versus rivaroxaban (n = 7 of 7) but not significantly different from dabigatran (n = 6 of 7). MB risk was significantly lower (n = 3 of 4) or not significantly different (n = 1 of 4) with dabigatran versus rivaroxaban. No evidence was identified for edoxaban.

CONCLUSION

DOACs were associated with similar or lower risks of MB versus warfarin. A lower MB risk was consistently observed for apixaban, but less consistently for dabigatran; MB risk was similar between rivaroxaban and warfarin. Among DOACs, the risk of MB with apixaban was consistently lower than with rivaroxaban, but similar to dabigatran.

Effect of Apixaban Versus Warfarin Use on Health Care Resource Utilization and Costs Among Elderly Patients with Nonvalvular Atrial Fibrillation

BACKGROUND

The clinical trial ARISTOTLE showed that apixaban was superior to warfarin in reducing the risks of stroke and bleeding among patients with nonvalvular atrial fibrillation (NVAF). Further study of the effect of apixaban versus warfarin use on health care resource utilization (HCRU) and associated costs in the real-world setting is warranted, especially among elderly patients who are at higher risk of stroke and bleeding.

OBJECTIVE

To compare HCRU and costs among elderly NVAF patients treated with apixaban versus warfarin in the United States.

METHODS

Elderly patients (aged ≥ 65 years) with Medicare coverage who initiated apixaban or warfarin were identified from the Humana research database during January 1, 2013-September 30, 2015. Patients were required to have 12 months of continuous insurance coverage before drug initiation (baseline period) and an atrial fibrillation diagnosis during the baseline period or on the date of drug initiation. NVAF patients were grouped into cohorts depending on the drug initiated. Propensity score matching (PSM) was conducted to control for differences in demographics and clinical characteristics of study cohorts. Patients were followed after the index date for a variable length of follow-up. All-cause and disease-specific HCRU and costs during the follow-up were evaluated before and after PSM and reported as per patient per year.

RESULTS

Of the overall (unmatched) population, 8,250 patients (mean age: 78.0 years) initiated apixaban and 14,051 patients (mean age: 78.2 years) initiated warfarin. Among NVAF patients who initiated apixaban versus those who initiated warfarin, mean Charlson Comorbidity Index (CCI) scores (3.0 vs. 3.4, P < 0.001); stroke risk scores, including CHADS₂ (2.7 vs. 2.9, P < 0.001) and CHA₂DS₂-VASc (4.6 vs. 4.7, P < 0.001); and bleeding risk scores, including HAS-BLED (3.1 vs. 3.2, P < 0.001), were lower. Additionally, total annual all-cause health care costs were lower during the baseline period for patients treated with apixaban versus warfarin ($17,077 vs. $20,236, P < 0.001). After PSM, 14,214 patients were matched, with 7,107 in each cohort. Mean age, CCI score, and stroke and bleeding risks were similar between matched cohorts, as were total all-cause health care costs during the baseline period. During the follow-up among matched cohorts, apixaban versus warfarin treatment was associated with higher annual pharmacy costs ($5,159 vs. $2,867, P < 0.001) but lower annual inpatient ($8,327 vs. $14,296, P < 0.001), outpatient ($9,655 vs. $11,469, P < 0.001), and total all-cause health care costs ($23,141 vs. $28,633, P < 0.001), which were reflective of lower inpatient, outpatient, and all-cause HCRU among apixaban-treated patients. Furthermore, bleeding-related ($2,101 vs. $3,963, P < 0.001) and stroke-related ($652 vs. $1,178, P = 0.001) annual medical costs were lower for patients treated with apixaban versus warfarin.

CONCLUSIONS

After controlling for differences in patient characteristics, in the real-world setting apixaban versus warfarin use was associated with less HCRU and lower total all-cause health care costs and costs for bleeding- and stroke-related medical services, but greater pharmacy costs, among elderly NVAF patients.

DISCLOSURES

This study was sponsored by Pfizer and Bristol-Myers Squibb. Deitelzweig is a consultant for Pfizer and Bristol-Myers Squibb and has served on their advisory boards and received speaker fees. Deitelzweig also serves as consultant and advisory board member to Portola and Janssen. Luo, Trocio, and Mardekian are employees of Pfizer and own stock in the company. Gupta and Curtice are employees of Bristol-Myers Squibb and own stock in the company. Lingohr-Smith, Menges, and Lin are employees of Novosys Health, which received research funds from Pfizer and Bristol-Myers Squibb to conduct this study and develop the manuscript. Study concept and design were primarily contributed by Deitelzweig, Luo, and Gupta, along with Trocio, Mardekian, Curtice, and Lin. Lin, Menges, and Lingohr-Smith took the lead in data collection, with assistance from the other authors. Data interpretation was performed by Deitelzweig, Menges, and Lin, with assistance from the other authors. The manuscript was written by Lingohr-Smith and Menges, along with the other authors, and revised by all the authors. Some aspects of this study were presented at the American Heart Association Scientific Sessions in New Orleans, Louisiana, November 12-16, 2016.