Combined use of warfarin and oral P2Y12 inhibitors in patients with atrial fibrillation and acute coronary syndrome

Clin Cardiol. 2014 Mar;37(3):152-9. doi: 10.1002/clc.22231. Epub 2013 Dec 11.


Background: Although atrial fibrillation (AF) occurs frequently in patients hospitalized with acute coronary syndrome (ACS), strategies for prevention of thromboembolic complications are poorly characterized.

Hypothesis: We sought to examine exposure to warfarin and P2Y12 inhibitors and clinical outcomes among patients with AF and ACS.

Methods: Patients age >65 years hospitalized with a primary diagnosis of ACS and a secondary diagnosis of AF between 2007 and 2010 were identified in the Medicare 5% sample. Medication exposure was ascertained during a 90-day period following the index discharge using Medicare drug claims. Among patients who were alive and not readmitted during the ascertainment period, we examined the cumulative incidence of all-cause mortality and all-cause readmission by medication exposure at 1 year.

Results: A total of 2509 Medicare beneficiaries met the inclusion criteria. Among the 1633 patients (65%) who were alive and not readmitted during the 90-day ascertainment period, 24.0% received warfarin, 38.9% received P2Y12 inhibitors, 10.2% received combination therapy, and 26.8% received neither therapy. Readmission rates were high in all groups at 1 year (warfarin, 47.5%; P2Y12 inhibitors, 46.6%; combination therapy, 38.0%; and neither therapy, 39.3%), and the overall 1-year mortality rate was 12.5%.

Conclusions: Among Medicare beneficiaries with AF and ACS, combination therapy with warfarin and P2Y12 inhibitor was uncommon during the 90-day ascertainment period, and more than one-quarter of patients had no claims for warfarin or P2Y12 inhibitors. Rates of all-cause readmission and mortality within 1 year of hospitalization for ACS were high.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Acute Coronary Syndrome / drug therapy*
  • Acute Coronary Syndrome / mortality
  • Aged
  • Aged, 80 and over
  • Anticoagulants / therapeutic use*
  • Atrial Fibrillation / drug therapy*
  • Atrial Fibrillation / mortality
  • Cardiovascular Diseases / epidemiology
  • Cellulitis / epidemiology
  • Comorbidity
  • Drug Therapy, Combination
  • Drug Utilization
  • Female
  • Gastrointestinal Diseases / epidemiology
  • Humans
  • Male
  • Medicare
  • Myocardial Revascularization / statistics & numerical data
  • Patient Readmission / statistics & numerical data*
  • Pulmonary Disease, Chronic Obstructive / epidemiology
  • Purinergic P2Y Receptor Antagonists / therapeutic use*
  • Stents
  • Thromboembolism / prevention & control
  • United States
  • Warfarin / therapeutic use*


  • Anticoagulants
  • Purinergic P2Y Receptor Antagonists
  • Warfarin