Effectiveness and safety of apixaban vs warfarin among venous thromboembolism patients at high-risk of bleeding

PLoS One. 2022 Sep 23;17(9):e0274969. doi: 10.1371/journal.pone.0274969. eCollection 2022.

Abstract

This study evaluated effectiveness and safety of apixaban versus warfarin among venous thromboembolism patients at high-risk of bleeding (defined as having at least one of the following bleeding risk factors: ≥75 years; used antiplatelet, NSAIDs, or corticosteroids; had prior gastrointestinal bleeding or gastrointestinal-related conditions; late stage chronic kidney disease). Adult venous thromboembolism patients initiating apixaban or warfarin with ≥1 bleeding risk factor were identified from Medicare and four commercial claims databases in the United States. To balance characteristics between apixaban and warfarin patients, stabilized inverse probability treatment weighting was conducted. Cox proportional hazards models were used to estimate the risk of recurrent venous thromboembolism, major bleeding, and clinically relevant non-major bleeding. In total, 88,281 patients were identified. After inverse probability treatment weighting, the baseline patient characteristics were well-balanced between the two cohorts. Among venous thromboembolism patients at high-risk of bleeding, apixaban was associated with significantly lower risk of recurrent venous thromboembolism, major bleeding and clinically relevant non-major bleeding. No significant interactions were observed between treatment and number of risk factors on major bleeding and clinically relevant non-major bleeding or between treatment and type of bleeding risk factors on any of the outcomes. In conclusion, apixaban was associated with significantly lower risk of recurrent venous thromboembolism and bleeding among venous thromboembolism patients at high-risk of bleeding. Effects were generally consistent across subgroups of patients with different number or type of bleeding risk factors.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Aged
  • Anti-Inflammatory Agents, Non-Steroidal / therapeutic use
  • Anticoagulants / adverse effects
  • Hemorrhage / chemically induced
  • Humans
  • Medicare
  • Pyrazoles
  • Pyridones / adverse effects
  • Retrospective Studies
  • United States
  • Venous Thromboembolism* / complications
  • Venous Thromboembolism* / drug therapy
  • Warfarin* / adverse effects

Substances

  • Anti-Inflammatory Agents, Non-Steroidal
  • Anticoagulants
  • Pyrazoles
  • Pyridones
  • apixaban
  • Warfarin

Grants and funding

Funding: This research was funded by Bristol Myers Squibb and Pfizer. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.