Discontinuation risk comparison among 'real-world' newly anticoagulated atrial fibrillation patients: Apixaban, warfarin, dabigatran, or rivaroxaban

PLoS One. 2018 Apr 30;13(4):e0195950. doi: 10.1371/journal.pone.0195950. eCollection 2018.

Abstract

Discontinuation of oral anticoagulants may expose non-valvular atrial fibrillation (NVAF) patients to an increased risk of stroke. This study describes the real-world discontinuation rates and compared the risk of drug discontinuation among NVAF patients initiating apixaban, warfarin, dabigatran, or rivaroxaban. This retrospective cohort study evaluated newly-anticoagulated NVAF patients in the MarketScan® data population from 01/01/2012 through 12/31/2014. Discontinuation was defined as a lack of subsequent prescription of the index drug within 30 days after the last supply day of the last prescription. A Cox model was used to estimate the hazard ratio (HR) of discontinuation, adjusted for age, sex, and comorbidities. Among 45,361 eligible NVAF patients, 15,461 (34.1%) initiated warfarin; 7,438 (16.4%) apixaban; 4,661 (10.3%) dabigatran; and 17,801 (39.2%) initiated rivaroxaban treatment. Compared to warfarin, patients who initiated dabigatran (adjusted HR [aHR]: 0.84, 95% confidence interval [CI]: 0.80-0.87, P<0.001), rivaroxaban (aHR: 0.70, 95% CI: 0.68-0.73, P<0.001), or apixaban (aHR: 0.57, 95% CI: 0.55-0.60, P<0.001) were 16%, 30%, and 43% less likely to discontinue treatment, respectively. When compared to apixaban, patients who initiated dabigatran (aHR: 1.46, 95% CI: 1.38-1.54, P<0.001) or rivaroxaban (aHR: 1.23, 95% CI: 1.17-1.28, P<0.001) were more likely to discontinue treatment. Among newly-anticoagulated NVAF patients in the real-world setting, initiation on rivaroxaban, dabigatran, or apixaban was associated with a significantly lower risk of discontinuation compared to warfarin. When compared to apixaban, patients who initiated treatment with warfarin, dabigatran, or rivaroxaban were more likely to discontinue treatment.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adolescent
  • Adult
  • Aged
  • Anticoagulants / adverse effects*
  • Atrial Fibrillation / drug therapy*
  • Dabigatran / adverse effects
  • Female
  • Hemorrhage / chemically induced
  • Hemorrhage / epidemiology*
  • Humans
  • Incidence
  • Male
  • Middle Aged
  • Prognosis
  • Pyrazoles / adverse effects
  • Pyridones / adverse effects
  • Retrospective Studies
  • Risk Factors
  • Rivaroxaban / adverse effects
  • Stroke / chemically induced
  • Stroke / epidemiology*
  • United States / epidemiology
  • Warfarin / adverse effects
  • Withholding Treatment / statistics & numerical data*
  • Young Adult

Substances

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

Grants and funding

This study was sponsored by Bristol-Myers Squibb Company, Princeton, NJ, USA and Pfizer Inc., New York, New York, USA. The funder provided support in the form of salaries for authors XP, SK, HK, JM, CM, HM, but did not have any additional role in the study design, data collection and analysis, decision to publish, or preparation of the manuscript.