Journal of Thrombosis and Thrombolysis

, Volume 46, Issue 3, pp 316–324 | Cite as

Warfarin for prevention of thromboembolism in atrial fibrillation: comparison of patient characteristics and outcomes of the “Real-World” Michigan Anticoagulation Quality Improvement Initiative (MAQI2) registry to the RE-LY, ROCKET-AF, and ARISTOTLE trials

  • Andrew B. Hughey
  • Xiaokui Gu
  • Brian Haymart
  • Eva Kline-Rogers
  • Steve Almany
  • Jay Kozlowski
  • Dennis Besley
  • Gregory D. Krol
  • Syed Ahsan
  • Scott Kaatz
  • James B. Froehlich
  • Geoffrey D. Barnes


Randomized controlled trials (RCTs) examining warfarin use for stroke prevention in atrial fibrillation (AF) may not accurately reflect real-world populations. We aimed to determine the representativeness of the RCT populations to real-world patients and to describe differences in the characteristics of trial populations from trial eligible patients in a real-world setting. We hypothesized that a significant fraction of real-world patients would not qualify for the RE-LY, ROCKET-AF, and ARISTOTLE trials and that real-world patients qualifying for the studies may have more strokes and bleeding events. We compared the inclusion and exclusion criteria, patient characteristics, and clinical outcomes from RE-LY, ROCKET-AF, and ARISTOTLE against data from the Michigan Anticoagulation Quality Improvement Initiative (MAQI2), a regional network of six community- and academic-based anticoagulation clinics. Of the 1446 non-valvular AF patients in the MAQI2 registry taking warfarin, approximately 40–60% would meet the selection criteria used in RE-LY (788, 54.5%), ROCKET-AF (566, 39.1%), and ARISTOTLE (866, 59.9%). The most common reasons for exclusion from one or more trial were anemia (15.1%), other concurrent medications (11.2%), and chronic kidney disease (9.4%). Trial-eligible MAQI2 patients were older, more frequently female, with a higher rate of paroxysmal AF, and lower rates of congestive heart failure, previous stroke, and previous myocardial infarction than the trial populations. MAQI2 patients eligible for each trial had a lower rate of stroke and similar rate of major bleeding than was observed in the trials. A sizable proportion of real-world AF patients managed in anticoagulation clinics would not have been eligible for the RE-LY, ROCKET-AF, and ARISOTLE trials. The expected stroke risk reduction and bleeding risk among real-world AF patients on warfarin may not be congruent with published clinical trial data.


Atrial fibrillation Anticoagulation Warfarin Real world Outcomes 



Blue Cross-Blue Shield of Michigan/Blue Care Network provided funding for data collection and analysis, but was not involved in the interpretation of the data, the decision to publish, or the preparation of the manuscript. GB is supported on the NIH grant T32-HL007853.

Compliance with Ethical Standards

Conflict of interest

Steve Almany: Grant support from Boston Scientific Watchman, Michigan Anticoagulation Quality, and Abbott Absorb trial. Consultant for Kona, Trice Orthopedics, and Micardia. Ownership/partnership/principal with Biostar Ventures and Ablative Solutions. Scott Kaatz: Grant support from Boehringer-Ingelheim, Bristol-Myers Squibb, Bayer/Jansen/Johnson and Johnson, Eisai, Iverson Genetics Diagnostics/Medicare, National Institute of Health, Canadian Institute of Health Research, Blue Cross/Blue Shield of Michigan. Speaker honorarium from Jansen/Johnson and Johnson, Boehringer-Ingelheim, and Bristol-Myers Squibb. Consultant for Boehringer Ingelheim, Bristol-Myers Squibb/Pfizer, Jansen/Johnson and Johnson, and Daiichi Sankyo. Non-profit board membership with AC Forum, National Certification Board of Anticoagulation Providers, and National Blood Clot Alliance Medical and Scientific Advisory Board. James B. Froehlich: Consultant for Merck, Bristol-Meyers Squibb, Pfizer, Sanofi-Aventis, Janssen Pharamaceuticals, Aralez and Ortho-McNeil. Research grants from Sanofi-Aventis, Blue Cross/Blue Shield of Michigan, Mardigian Foundation, Fibromuscular Disease Society of America. Geoffrey D. Barnes: Research grant support from Bristol Meyers Squibb/Pfizer and Blue Cross/Blue Shield of Michigan. Consultant for Portola and Aralez. Andrew B. Hughey, Xiaokui Gu, Brian Haymart, Eva Kline-Rogers, Jay Kozlowski, Dennis Besley, Gregory D. Krol, Syed Ahsan, declares that they have no conflict of interest.

Supplementary material

11239_2018_1698_MOESM1_ESM.docx (14 kb)
Supplementary material 1 (DOCX 13 KB)


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Copyright information

© Springer Science+Business Media, LLC, part of Springer Nature 2018

Authors and Affiliations

  • Andrew B. Hughey
    • 1
  • Xiaokui Gu
    • 1
  • Brian Haymart
    • 1
  • Eva Kline-Rogers
    • 1
  • Steve Almany
    • 2
  • Jay Kozlowski
    • 3
  • Dennis Besley
    • 4
  • Gregory D. Krol
    • 5
  • Syed Ahsan
    • 5
  • Scott Kaatz
    • 6
  • James B. Froehlich
    • 1
  • Geoffrey D. Barnes
    • 1
  1. 1.Frankel Cardiovascular CenterUniversity of Michigan Health SystemAnn ArborUSA
  2. 2.Michigan Heart GroupWilliam Beaumont HospitalRoyal OakUSA
  3. 3.Cardiology and Vascular AssociatesHuron Valley-Sinai HospitalCommerce TownshipUSA
  4. 4.West Michigan HeartGrand RapidsUSA
  5. 5.Henry Ford HospitalDetroitUSA
  6. 6.Hurley Medical CenterFlintUSA

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