Comparison of effectiveness and safety of treatment with apixaban vs. other oral anticoagulants among elderly nonvalvular atrial fibrillation patients

Curr Med Res Opin. 2017 Oct;33(10):1745-1754. doi: 10.1080/03007995.2017.1334638. Epub 2017 Aug 29.

Abstract

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.

Keywords: Elderly; apixaban; dabigatran; effectiveness; nonvalvular atrial fibrillation; oral anticoagulants; rivaroxaban; safety; warfarin.

Publication types

  • Comparative Study

MeSH terms

  • Aged
  • Aged, 80 and over
  • Anticoagulants / adverse effects
  • Anticoagulants / therapeutic use*
  • Atrial Fibrillation / drug therapy*
  • Dabigatran / administration & dosage
  • Dabigatran / adverse effects
  • Female
  • Hemorrhage / chemically induced*
  • Humans
  • Male
  • Propensity Score
  • Pyrazoles / adverse effects
  • Pyrazoles / therapeutic use*
  • Pyridones / adverse effects
  • Pyridones / therapeutic use*
  • Retrospective Studies
  • Rivaroxaban / adverse effects
  • Rivaroxaban / therapeutic use
  • Stroke / prevention & control
  • Warfarin / adverse effects
  • Warfarin / therapeutic use

Substances

  • Anticoagulants
  • Pyrazoles
  • Pyridones
  • apixaban
  • Warfarin
  • Rivaroxaban
  • Dabigatran