The Association Between Prior Use of Aspirin and/or Warfarin and the In-hospital Management and Outcomes in Patients Presenting With Acute Coronary Syndromes: Insights From the Global Registry of Acute Coronary Events (GRACE)

UMMS Affiliation

Center for Outcomes Research; Department of Medicine, Division of Cardiovascular Medicine

Publication Date


Document Type



Acute Coronary Syndrome; Aspirin; Warfarin; Treatment Outcome


Cardiovascular Diseases | Health Services Research


BACKGROUND: The role of acetylsalicylic acid (ASA [aspirin]) and warfarin in secondary prevention after acute coronary syndromes (ACS) is well established. However, there are sparse data comparing the presentation and outcomes of patients who present with ACS while on ASA and/or warfarin therapy and those on neither.

METHODS: Using data from the Canadian Global Registry of Acute Coronary Events (GRACE), we stratified 14,090 ACS patients into 4 groups according to prior use of antithrombotic therapies and compared in-hospital management and outcomes.

RESULTS: Among 14,090 ACS patients, 7411 (52.6%) were not on prior ASA or warfarin therapy, 5724 (40.6%) were on ASA only, 593 (4.2%) were on warfarin only, and 362 (2.6%) were on both ASA and warfarin. ACS patients taking ASA and/or warfarin were older with more comorbidities than the patients on neither drug. Patients receiving prior warfarin only or ASA and warfarin were less likely to receive guideline-recommended therapies. Patients who were taking prior warfarin only had higher unadjusted rates of death, death and/or reinfarction (re-MI), congestive heart failure (CHF), and major bleeding as compared with patients on no prior therapy. Furthermore, patients who were taking ASA and warfarin had higher unadjusted rates of death and/or re-MI and CHF than patients on prior ASA only.

CONCLUSIONS: ACS patients on prior warfarin are a high-risk population, yet they receive less guideline-recommended therapies and have higher unadjusted adverse event rates during their index hospitalization. With the increasing use of oral anticoagulants, clinical trials are needed to guide the optimal management of these ACS patients. Inc. All rights reserved.

DOI of Published Version



Can J Cardiol. 2012 Jan;28(1):48-53. Epub 2011 Nov 23. Link to article on publisher's site

Journal/Book/Conference Title

The Canadian journal of cardiology

Related Resources

Link to Article in PubMed

PubMed ID