A comparison of the safety and effectiveness of dabigatran and warfarin in non-valvular atrial fibrillation patients in a large healthcare system

SummaryDabigatran is approved for stroke risk reduction in patients with nonvalvular atrial fibrillation (NVAF). Data from diverse clinical practice settings will help establish whether the risk:benefit ratio seen in clinical trials is comparable with routine clinical care. This study aimed to compare the safety and effectiveness of dabigatran and warfarin in clinical practice. We undertook a propensity score-matched (PSM) cohort study (N=12,793 per group; mean age 74) comparing treatment with dabigatran or warfarin in the US Department of Defense claims database, October 2009 to July 2013. Treatment-naïve patients with first prescription claim for dabigatran (either FDA-approved dose) or warfarin between October 2010 and July 2012 (index) and a diagnosis of NVAF during the 12 months before index date were included. Primary outcomes were stroke and major bleeding. Secondary outcomes included ischaemic and haemorrhagic stroke, major gastrointestinal (GI), urogenital or other bleeding, myocardial infarction (MI) and death. Time-to-event was investigated using Kaplan-Meier survival analyses. Outcomes comparisons were made utilising Cox-proportional hazards models of PSM groups. Dabigatran users experienced fewer strokes (adjusted hazard ratio [95 % confidence intervals] 0.73 [0.55–0.97]), major intracranial (0.49 [0.30–0.79]), urogenital (0.36 [0.18–0.74]) and other (0.38 [0.22–0.66]) bleeding, MI (0.65 [0.45–0.95]) and deaths (0.64 [0.55–0.74]) than the warfarin group. Major bleeding (0.87 [0.74–1.03]) and major GI bleeding (1.13 [0.94–1.37]) was similar between groups and major lower GI bleeding events were more frequent (1.30 [1.04–1.62]) with dabigatran. In conclusion, compared with warfarin, dabigatran treatment was associated with a lower risk of stroke and most outcomes measured, but increased incidence of major lower GI bleeding.

Download Full-text

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

Therapeutic Advances in Gastroenterology ◽

10.1177/1756284821997352 ◽

2021 ◽

Vol 14 ◽

pp. 175628482199735

Author(s):

Steven Deitelzweig ◽

Allison Keshishian ◽

Amiee Kang ◽

Amol D. Dhamane ◽

Xuemei Luo ◽

...

Keyword(s):

Atrial Fibrillation ◽

Major Bleeding ◽

Oral Anticoagulant ◽

Proportional Hazards ◽

Bleeding Event ◽

Cox Proportional Hazards ◽

High Rate ◽

Gi Bleeding ◽

Increased Risk ◽

Gi Bleed

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.

Download Full-text

Edoxaban treatment of elderly patients with atrial fibrillation in routine clinical practice: 1-year results of the non-interventional Global ETNA-AF program

European Heart Journal ◽

10.1093/ehjci/ehaa946.0663 ◽

2020 ◽

Vol 41 (Supplement_2) ◽

Author(s):

T Yamashita ◽

C.C Wang ◽

Y.-H Kim ◽

R De Caterina ◽

P Kirchhof ◽

...

Keyword(s):

Atrial Fibrillation ◽

Clinical Practice ◽

Major Bleeding ◽

Intracranial Haemorrhage ◽

Clinical Care ◽

Oral Anticoagulants ◽

Clinical Event ◽

Funding Source ◽

Private Company ◽

All Cause Mortality

Abstract Background The prevalence of atrial fibrillation (AF) and the need for appropriate anticoagulation increase with age. The benefit/risk profile of direct oral anticoagulants such as edoxaban in elderly population with AF in regular clinical practice is therefore of particular interest. Purpose Analyses of Global ETNA-AF data were performed to report patient characteristics, edoxaban treatment, and 1-year clinical events by age subgroups. Methods Global ETNA-AF is a multicentre, prospective, noninterventional program conducted in Europe, Japan, Korea, Taiwan, and other Asian countries. Demographics, baseline characteristics, and 1-year clinical event data were analysed in four age subgroups. Results Of 26,823 patients included in this analysis, 50.4% were ≥75 years old and 11.6% were ≥85 years. Increase in age was generally associated with lower body weight, lower creatinine clearance, higher CHA2DS2-VASc and HAS-BLED scores, and a higher percentage of patients receiving the reduced dose of 30 mg daily edoxaban. At 1-year, rates of ISTH major bleeding and ischaemic stroke were generally low across all age subgroups. The proportion of intracranial haemorrhage within major bleeding events was similar across age groups. All-cause mortality increased with age more than cardiovascular mortality. Conclusion Data from Global ETNA-AF support the safety and effectiveness of edoxaban in elderly AF patients (including ≥85 years) in routine clinical care with only a small increase in intracranial haemorrhage. The higher all-cause mortality with increasing age is not driven by cardiovascular causes. Funding Acknowledgement Type of funding source: Private company. Main funding source(s): Daiichi Sankyo

Download Full-text

Effectiveness and safety of apixaban versus warfarin in non-valvular atrial fibrillation patients in “real-world” clinical practice

Thrombosis and Haemostasis ◽

10.1160/th17-01-0068 ◽

2017 ◽

Vol 117 (06) ◽

pp. 1072-1082 ◽

Cited By ~ 69

Author(s):

Xiaoyan Li ◽

Steve Deitelzweig ◽

Allison Keshishian ◽

Melissa Hamilton ◽

Ruslan Horblyuk ◽

...

Keyword(s):

Atrial Fibrillation ◽

Major Bleeding ◽

Real World ◽

Proportional Hazards ◽

Significant Risk ◽

Haemorrhagic Stroke ◽

Cox Proportional Hazards ◽

Kaplan Meier ◽

Cox Proportional Hazards Models ◽

Warfarin Treatment

SummaryThe ARISTOTLE trial showed a risk reduction of stroke/systemic embolism (SE) and major bleeding in non-valvular atrial fibrillation (NVAF) patients treated with apixaban compared to warfarin. This retrospective study used four large US claims databases (MarketScan, PharMetrics, Optum, and Humana) of NVAF patients newly initiating apixaban or warfarin from January 1, 2013 to September 30, 2015. After 1:1 warfarin-apixaban propensity score matching (PSM) within each database, the resulting patient records were pooled. Kaplan-Meier curves and Cox proportional hazards models were used to estimate the cumulative incidence and hazard ratios (HRs) of stroke/SE and major bleeding (identified using the first listed diagnosis of inpatient claims) within one year of therapy initiation. The study included a total of 76,940 (38,470 warfarin and 38,470 apixaban) patients. Among the 38,470 matched pairs, 14,563 were from MarketScan, 7,683 were from PharMetrics, 7,894 were from Optum, and 8,330 were from Humana. Baseline characteristics were balanced between the two cohorts with a mean (standard deviation [SD]) age of 71 (12) years and a mean (SD) CHA2DS2-VASc score of 3.2 (1.7). Apixaban initiators had a significantly lower risk of stroke/SE (HR: 0.67, 95 % CI: 0.59–0.76) and major bleeding (HR: 0.60, 95 % CI: 0.54–0.65) than warfarin initiators. Different types of stroke/SE and major bleeding – including ischaemic stroke, haemorrhagic stroke, SE, intracranial haemorrhage, gastrointestinal bleeding, and other major bleeding – were all significantly lower for apixaban compared to warfarin treatment. Subgroup analyses (apixaban dosage, age strata, CHA2DS2-VASc or HAS-BLED score strata, or dataset source) all show consistently lower risks of stroke/SE and major bleeding associated with apixaban as compared to warfarin treatment. This is the largest “real-world” study on apixaban effectiveness and safety to date, showing that apixaban initiation was associated with significant risk reductions in stroke/SE and major bleeding compared to warfarin initiation after PSM. These benefits were consistent across various high-risk subgroups and both the standard-and low-dose apixaban dose regimens.Note: The review process for this manuscript was fully handled by Christian Weber, Editor in Chief.Supplementary Material to this article is available online at www.thrombosis-online.com.

Download Full-text

Abstract 17152: Frequency and Management of Major Bleeding in Atrial Fibrillation Patients Treated With Warfarin and Non-vitamin K Oral Anticoagulants in Community Practice: Results From the ORBIT-AF II Registry

Circulation ◽

10.1161/circ.132.suppl_3.17152 ◽

2015 ◽

Vol 132 (suppl_3) ◽

Author(s):

Benjamin A Steinberg ◽

DaJuanicia N Simon ◽

Laine Thomas ◽

Jack Ansell ◽

Gregg C Fonarow ◽

...

Keyword(s):

Atrial Fibrillation ◽

Clinical Practice ◽

Vitamin K ◽

Major Bleeding ◽

Oral Anticoagulants ◽

Recurrent Bleeding ◽

Bleeding Events ◽

Reversal Agents ◽

Major Bleeding Events

Background: Non-vitamin K oral anticoagulants (NOACs) are effective at preventing stroke in patients with atrial fibrillation (AF). However, little is known about the frequency of major bleeds on NOACs and how these events are managed in clinical practice. Methods: We assessed the rates, management, and outcomes of ISTH major bleeding events among AF patients in the ORBIT-AF II registry (mean follow-up 213 days). Results: Overall, 103 patients experienced 110 major bleeding events during follow-up n=90/4986 (1.8%) on NOAC, and n=20/1320 (1.5%) on warfarin. Patients with bleeding events on NOAC were slightly younger than those on warfarin (median age 76 vs. 80; p=0.2). Among mutually-exclusive bleeding types, intracranial bleeding was more common in warfarin treated patients than NOAC-treated (15% vs 6.7%), whereas GI bleeding was more common on NOACs (56% vs. 40%, overall p=0.1 for bleeding type). Management of bleeding differed by anticoagulation type: blood products and reversal agents were more commonly used in patients on warfarin (Table). No patient received prothrombin complexes, recombinant factor VIIa, aminocaproic acid, tranexamic acid, aprotinin, or desmopressin. Out of 90 major bleeding events in NOAC patients, only 1 was fatal (1%). Within 30 days following bleeding, there were no strokes and 1 TIA (NOAC). Following a major bleed, the recurrent bleeding rate in NOAC patients in the next 30-days was 4% and the death rate was 4%. Conclusions: Rates of major bleeding with NOACs in clinical practice are comparable to those reported in clinical trials. Compared with warfarin, bleeding among NOAC users was less likely intracranial and more likely to be GI. Management of bleeding in the setting of NOAC rarely includes reversal agents.

Download Full-text

Abstract 17617: History of Bleeding and Outcomes with Apixaban versus Warfarin in Patients with Atrial Fibrillation in the ARISTOTLE Trial

Circulation ◽

10.1161/circ.130.suppl_2.17617 ◽

2014 ◽

Vol 130 (suppl_2) ◽

Author(s):

Raffaele De Caterina ◽

Ulrika Andersson ◽

John H Alexander ◽

M.Cecilia Bahit ◽

Patrick J Commerford ◽

...

Keyword(s):

Atrial Fibrillation ◽

Body Weight ◽

Major Bleeding ◽

Proportional Hazards ◽

Proportional Hazards Model ◽

Cox Proportional Hazards ◽

Cox Proportional Hazards Model ◽

Channel Blockers ◽

Chads2 Score ◽

History Of

Background: History of bleeding is important in decisions for anticoagulation. We analyzed outcomes in relation to history of bleeding and randomized treatments in patients with atrial fibrillation (AF) in the ARISTOTLE trial. Methods: The on-treatment safety population included 18,140 patients receiving ≥1 dose of study drug, apixaban 5 mg bd (2.5 mg bd if 2 of the following: age >80 yrs; body weight <60 kg; or creatinine >133 μmol/L) or warfarin aiming for INR 2.0-3.0 (median TTR 66%), for a median of 1.8 yrs. Adjudicated outcomes in relation to randomization and history of bleeding were analyzed using a Cox proportional hazards model. Efficacy endpoints were analyzed in the intention-to-treat population. Results: A history of bleeding was reported in 3033 patients (16.7%), who more often were male (68% vs 64%, p <0.0005); with a history of prior stroke/TIA/systemic embolism (23% vs 19%, p <0.0001); diabetes (27% vs 24%, p=0.0010); higher CHADS2 score (CHADS2 >3: 35% vs 29%), age (mean [SD] 71 [9] vs 69 [10], p <0001) and body weight (86 [21] vs 84 [21], p <0.0001); lower creatinine clearance (77 [33] vs 80 [33], p=0.0007) and mean systolic blood pressure (131 [17] vs 132 [16], p=0.0027). Calcium channel blockers, statins, non-steroidal anti-inflammatory drugs and proton pump inhibitors were used more often in patients with vs without a history of bleeding. Major bleeding was the only outcome event occurring more frequently in patients with vs without a history of bleeding, HR 1.7 (95% CI 1.4-2.3) with apixaban and 1.5 (1.2-1.0) with warfarin. Primary efficacy and safety outcomes in relation to randomization, see Table. Conclusions: In patients with AF, a history of bleeding was associated with several risk factors for stroke and bleeding and, accordingly, a higher bleeding risk during anticoagulation. Benefits with apixaban vs warfarin as to stroke, mortality and major bleeding, are however consistent irrespective of bleeding history.

Download Full-text

Abstract 19119: Concomitant Use of Antiplatelet Therapy with Edoxaban or Warfarin in Patients with Atrial Fibrillation in the ENGAGE AF-TIMI 48 Trial

Circulation ◽

10.1161/circ.130.suppl_2.19119 ◽

2014 ◽

Vol 130 (suppl_2) ◽

Author(s):

Haiyan Xu ◽

Christian T Ruff ◽

Robert P Giugliano ◽

Sabina A Murphy ◽

Indravadan Patel ◽

...

Keyword(s):

Atrial Fibrillation ◽

Anticoagulant Therapy ◽

Major Bleeding ◽

Drug Exposure ◽

Proportional Hazards ◽

Absolute Risk ◽

Cox Proportional Hazards ◽

Relative Efficacy ◽

Double Blind ◽

Risk Of Bleeding

BACKGROUND: Patients with atrial fibrillation (AF) who receive both antiplatelet (AP) and anticoagulant therapy are at markedly higher risk of bleeding. The ENGAGE AF-TIMI 48 trial showed that both the high- (HD) and low-dose (LD) regimens of the once-daily factor Xa inhibitor edoxaban (Edox) were as effective as well-managed warfarin (Warf) (median TTR 68.4%) in preventing stroke or systemic embolism (SEE) with significant reductions in major bleeding and cardiovascular mortality. In this study, we assessed the relative efficacy and safety of Edox as compared with Warf in patients with and without concomitant use of AP therapy. METHODS: This was a randomized, double-blind, double-dummy trial comparing HD (60 mg daily, reduced to 30mg in patients with anticipated increased drug exposure) and LD (30 mg daily, reduced to 15mg) Edox with Warf. Dual AP therapy was prohibited while receiving study drug. Cox proportional hazards models were performed stratified by AP use at 3 months with treatment as a covariate. RESULTS: Of the 21,105 patients, 4,912 (23%) were receiving AP therapy at 3 months (92% aspirin). Patients who received concomitant AP therapy had higher rates of major bleeding compared to patients who did not (Fig). Both Edox regimens had similar relative efficacy in preventing stroke or SEE compared with Warf regardless of concomitant AP use (P int >0.10 for both) with consistent reductions in major bleeding (HD Edox vs. Warf: P int =0.91; LD Edox vs. Warf: P int =0.59). In patients randomized to LD Edox, AP therapy was associated with a further reduction in the net clinical outcome of death, stroke, SEE, or major bleeding (P int =0.02) compared with Warf. CONCLUSIONS: Regardless of concomitant AP therapy, both doses of Edox significantly reduced bleeding compared to well-managed Warf. The safety profile of Edox may be particularly attractive in patients with AF who receive a combination of AP and anticoagulant therapy because of higher absolute risk of bleeding.

Download Full-text

Abstract P005: Comparative Effectiveness of Rivaroxaban versus Warfarin for the Treatment of Patients with Non-valvular Atrial Fibrillation

Circulation ◽

10.1161/circ.133.suppl_1.p005 ◽

2016 ◽

Vol 133 (suppl_1) ◽

Author(s):

Faye L Norby ◽

Lindsay G Bengtson ◽

Lin Y Chen ◽

Richard F MacLehose ◽

Pamela L Lutsey ◽

...

Keyword(s):

Atrial Fibrillation ◽

Ischemic Stroke ◽

Real World ◽

Proportional Hazards ◽

Large Population ◽

Population Based ◽

Cox Proportional Hazards ◽

Gi Bleeding ◽

Cox Proportional Hazards Models ◽

The Us

Background: Rivaroxaban is a novel oral anticoagulant approved in the US in 2011 for prevention of stroke and systemic embolism in patients with non-valvular atrial fibrillation (NVAF). Information on risks and benefits among rivaroxaban users in real-world populations is limited. Methods: We used data from the US MarketScan Commercial and Medicare Supplemental databases between 2010 and 2013. We selected patients with a history of NVAF and initiating rivaroxaban or warfarin. Rivaroxaban users were matched with up to 5 warfarin users by age, sex, database enrollment date and drug initiation date. Ischemic stroke, intracranial bleeding (ICB), myocardial infarction (MI), and gastrointestinal (GI) bleeding outcomes were defined by ICD-9-CM codes in an inpatient claim after drug initiation date. Cox proportional hazards models were used to assess the association between rivaroxaban vs. warfarin use and outcomes adjusting for age, sex, and CHA2DS2-VASc score. Separate models were used to compare a) new rivaroxaban users with new warfarin users, and b) switchers from warfarin to rivaroxaban to continuous warfarin users. Results: Our analysis included 34,998 rivaroxaban users matched to 102,480 warfarin users with NVAF (39% female, mean age 71), in which 487 ischemic strokes, 179 ICB, 647 MI, and 1353 GI bleeds were identified during a mean follow-up of 9 months. Associations of rivaroxaban vs warfarin were similar in new users and switchers; therefore we pooled both analyses. Rivaroxaban users had lower rates of ICB (hazard ratio (HR) (95% confidence interval (CI)) = 0.72 (0.46, 1.12))) and ischemic stroke (HR (95% CI) = 0.88 (0.68, 1.13)), but higher rates of GI bleeding (HR (95% CI) = 1.15 (1.01, 1.33)) when compared to warfarin users (table). Conclusion: In this large population-based study of NVAF patients, rivaroxaban users had a non-significant lower risk of ICB and ischemic stroke than warfarin users, but a higher risk of GI bleeding. These real-world findings are comparable to results reported in published clinical trials.

Download Full-text

Abstract 15467: Impact of Thrombocytopenia on Clinical Outcomes in Atrial Fibrillation Patients With Anemia: The Fushimi Af Registry

Circulation ◽

10.1161/circ.142.suppl_3.15467 ◽

2020 ◽

Vol 142 (Suppl_3) ◽

Author(s):

Kenjiro Ishigami ◽

Syuhei Ikeda ◽

KOSUKE DOI ◽

Yasuhiro Hamatani ◽

Akiko Fujino ◽

...

Keyword(s):

Atrial Fibrillation ◽

Clinical Outcomes ◽

Major Bleeding ◽

Proportional Hazards ◽

Cox Proportional Hazards ◽

Antithrombotic Drugs ◽

Prospective Survey ◽

Kaplan Meier ◽

Significant Difference ◽

Independent Determinant

Introduction: Anemia has been reported to be associated with poor prognosis in patients with atrial fibrillation (AF). Concomitant thrombocytopenia (TP) may or may not affect the prescription of antithrombotic drugs and clinical outcomes in these patients. Methods: The Fushimi AF Registry is a community-based prospective survey of AF patients in Fushimi-ku, Kyoto. We defined TP as platelet counts less than 150,000/μL and anemia as hemoglobin less than 11 g/dL. Among 666 patients with anemia, we compared the clinical backgrounds and outcomes of those with TP (n=183) and those without (n=483). Results: Compared with patients without TP, patients with TP were more likely to have chronic kidney disease (75.4% vs. 61.8%, p=0.001), and less likely to have hypertension (58.5% vs. 67.0%, p=0.0393), and less likely to have dyslipidemia (27.3% vs. 38.3%, p=0.0079). Age, sex, body weight, CHADS 2 score, CHA 2 DS 2 -VASc score, HAS-BLED score, and previous major bleeding were comparable between the groups. Furthermore, prescription of anti-thrombotic drugs was comparable (Figure A). On Kaplan-Meier analysis, the incidence of all-cause death was higher in TP group (hazard ratio [HR] 1.52; 95% confidence interval [CI] 1.20-1.91, p<0.05) (Figure B-1). There was no significant difference in other adverse events between patients with and without TP (major bleeding: HR 1.11; 95% CI 0.41-3.31, p=0.8, hospitalization for heart failure: HR 1.11; 95% CI 0.74-1.61, p= 0.61 and stroke or systemic embolism: HR 0.91; 95% CI 0.43-1.78, p=0.80) (Figure B-2, 3, 4). Multivariate Cox proportional hazards regression analysis adjusting for potential confounders revealed that TP was an independent determinant of all-cause death (adjusted HR: 1.41, 95% CI; 1.11-1.78, p=0.006). Conclusions: Concomitant TP in AF patients with anemia did not affect the prescription of antithrombotic drugs, and was independently associated with all-cause death in the Fushimi AF Registry.

Download Full-text

Risk of Recurrent Bleeding Events in Nonvalvular Atrial Fibrillation Treated with Vitamin K Antagonists: A Clinical Practice Research Datalink Study

TH Open ◽

10.1055/s-0039-1698413 ◽

2019 ◽

Vol 03 (04) ◽

pp. e316-e324 ◽

Cited By ~ 1

Author(s):

Raza Alikhan ◽

Cinira Lefevre ◽

Ian Menown ◽

Steven Lister ◽

Alex Bird ◽

...

Keyword(s):

Atrial Fibrillation ◽

Clinical Practice ◽

Vitamin K ◽

Vitamin K Antagonists ◽

Practice Research ◽

Clinical Practice Research Datalink ◽

Recurrent Bleeding ◽

Bleeding Events ◽

Nonvalvular Atrial Fibrillation ◽

The Impact

Abstract Background There is little evidence on how the occurrence of a bleed in individuals on vitamin K antagonists (VKAs) impacts the risk of subsequent bleeds, and thromboembolic and ischemic events. Such information would help to inform treatment decisions following bleeds. Objective To estimate the impact of bleeding events on the risk of subsequent bleeds, venous thromboembolism (VTE), stroke, and myocardial infarction (MI) among patients initiating VKA treatment for new-onset nonvalvular atrial fibrillation (NVAF). Methods We conducted an observational cohort study using a linked Clinical Practice Research Datalink—Hospital Episode Statistics dataset. Among a cohort of individuals with NVAF, the risk of clinically relevant bleeding, VTE, stroke, and MI was compared between the period prior to the first bleed and the periods following each subsequent bleed. The rate and cost of general practitioner (GP) consultations, prescriptions, and hospitalizations were also compared across these periods. Results The risk of clinically relevant bleeding events was observed to be elevated at least twofold in all periods following the first bleeding event. The risk of VTE, stroke, and MI was not found to differ according to the number of clinically relevant bleeding events. The rate and cost of GP consultations, GP prescriptions, and hospitalizations were increased in all periods relative to the period prior to the first bleed. Conclusions The doubling in the risk of bleeding following the first bleed, taken alongside the stable risk of MI, VTE, and stroke, suggests that the risk–benefit balance for VKA treatment should be reconsidered following the first clinically relevant bleed.

Download Full-text

Abstract 20218: Comparative Effectiveness of Dabigatran and Rivaroxaban versus Warfarin in Patients With Non-Valvular Atrial Fibrillation

Circulation ◽

10.1161/circ.130.suppl_2.20218 ◽

2014 ◽

Vol 130 (suppl_2) ◽

Author(s):

Lindsay Bengtson ◽

Lin Chen ◽

Richard MacLehose ◽

Pamela Lutsey ◽

Alvaro Alonso

Keyword(s):

Atrial Fibrillation ◽

Ischemic Stroke ◽

Real World ◽

Proportional Hazards ◽

Oral Anticoagulants ◽

Cox Proportional Hazards ◽

Intracranial Bleeding ◽

Gi Bleeding ◽

Pharmacy Claims ◽

The Us

Background: In randomized trials, the new oral anticoagulants (NOAC) dabigatran and rivaroxaban have been at least as efficacious as warfarin in the prevention of ischemic stroke in patients with non-valvular atrial fibrillation (NVAF). Information on the effectiveness of NOACs versus warfarin in real-world populations in the US is more limited. Methods: We used data from the US MarketScan Commercial and Medicare Supplemental databases in the period 2010-12. We selected patients initiating oral anticoagulants after NVAF diagnosis, and with at least 6 months of enrollment before first anticoagulant use. Patients initiating dabigatran or rivaroxaban were matched with up to 5 warfarin users by age, sex, and time in the database. Outcomes of interest (ischemic stroke, intracranial bleeding, and gastrointestinal [GI] bleeding) were defined according to validated algorithms. Information on other comorbidities and medication use was obtained from inpatient, outpatient, and pharmacy claims. High-dimensional propensity score-adjusted Cox proportional hazards regression was used to estimate the association of NOACs vs warfarin with each outcome of interest. Results: The analysis included 32,918 dabigatran, 3,301 rivaroxaban and 92,633 warfarin users with NVAF. During an average 13-month follow-up (6 for rivaroxaban, 15 for dabigatran), 1035 ischemic strokes, 225 intracranial bleeds, and 1842 GI bleeds were identified. Rate of ischemic stroke was similar in patients initiating NOACs compared to those on warfarin. However, rate of intracranial bleeding was lower in patients using NOACs compared to warfarin users, while GI bleeding rate was higher in dabigatran users than warfarin users (Table). Conclusion: In this large real-world patient population, effectiveness of NOACs (compared to warfarin) for diverse outcomes was comparable to efficacy reported in the RE-LY and ROCKET-AF trials.

Download Full-text