Cited by 2,102Atrial Fibrillation Management and OutcomesAntiplatelet Therapy and Cardiovascular DiseasesAcute Ischemic Stroke Management

Effect of clopidogrel added to aspirin in patients with atrial fibrillation

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The ACTIVE Investigators·2009·New England Journal of Medicine

Abstract

BACKGROUND: Vitamin K antagonists reduce the risk of stroke in patients with atrial fibrillation but are considered unsuitable in many patients, who usually receive aspirin instead. We investigated the hypothesis that the addition of clopidogrel to aspirin would reduce the risk of vascular events in patients with atrial fibrillation. METHODS: A total of 7554 patients with atrial fibrillation who had an increased risk of stroke and for whom vitamin K-antagonist therapy was unsuitable were randomly assigned to receive clopidogrel (75 mg) or placebo, once daily, in addition to aspirin. The primary outcome was the composite of stroke, myocardial infarction, non-central nervous system systemic embolism, or death from vascular causes. RESULTS: At a median of 3.6 years of follow-up, major vascular events had occurred in 832 patients receiving clopidogrel (6.8% per year) and in 924 patients receiving placebo (7.6% per year) (relative risk with clopidogrel, 0.89; 95% confidence interval [CI], 0.81 to 0.98; P=0.01). The difference was primarily due to a reduction in the rate of stroke with clopidogrel. Stroke occurred in 296 patients receiving clopidogrel (2.4% per year) and 408 patients receiving placebo (3.3% per year) (relative risk, 0.72; 95% CI, 0.62 to 0.83; P<0.001). Myocardial infarction occurred in 90 patients receiving clopidogrel (0.7% per year) and in 115 receiving placebo (0.9% per year) (relative risk, 0.78; 95% CI, 0.59 to 1.03; P=0.08). Major bleeding occurred in 251 patients receiving clopidogrel (2.0% per year) and in 162 patients receiving placebo (1.3% per year) (relative risk, 1.57; 95% CI, 1.29 to 1.92; P<0.001). CONCLUSIONS: In patients with atrial fibrillation for whom vitamin K-antagonist therapy was unsuitable, the addition of clopidogrel to aspirin reduced the risk of major vascular events, especially stroke, and increased the risk of major hemorrhage. (ClinicalTrials.gov number, NCT00249873.)

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  • Antiplatelet therapy increases bleeding risk, especially dual antiplatelet therapy (2.0% vs. 1.3% with antiplatelet monotherapy; P < 0.001), with bleeding rates that are similar to those on oral anticoagulation.

    “Antiplatelet therapy increases bleeding risk, especially dual antiplatelet therapy (2.0% vs. 1.3% with antiplatelet monotherapy; P < 0.001), 433 with bleeding rates that are similar to those on OAC.354,362,431,434”

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  1. Singer DE, Albers GW, Dalen JE, et al. 4. Antithrombotic therapy in atrial fibrilla- tion: American College of Chest Physi- cians Evidence-Based Clinical Practice Guidelines (8th edition). Chest 2008;133: Suppl:546S-592S.

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Authors
The ACTIVE Investigators
Affiliations
Population Health Research Institute (CA)
Corresponding author
The ACTIVE Investigators
Venue
New England Journal of Medicine
Published
2009-05-14
Volume
360
Issue
20
Pages
2066-2078
ISSN
  • 0028-4793 (ISSN-L)
  • 1533-4406
OpenAlex
W2113089341
Cited by
2,102
References
25
Citations by year
2026: 10 · 2025: 16 · 2024: 25 · 2023: 19 · 2022: 23 · 2021: 55 · 2020: 65 · 2019: 73 · 2018: 75 · 2017: 115 · 2016: 166 · 2015: 205 · 2014: 209 · 2013: 264 · 2012: 286
FWCI
168.46
Type
journal article
Language
en
Open access
Locations
  • New England Journal of Medicine (publishedVersion)
  • PubMed (publishedVersion)
  • Pure Amsterdam UMC (publishedVersion)
  • UWA Profiles and Research Repository (UWA) (submittedVersion)
  • Data Archiving and Networked Services (DANS) (submittedVersion)
  • HAL (submittedVersion)
  • ArTS Archivio della ricerca di Trieste (University of Trieste https://www.units.it/) (submittedVersion)
  • Own your potential (DEAKIN) (submittedVersion)
  • Figshare (submittedVersion, cc-by)
  • University of Debrecen Electronic Archive (University of Debrecen) (submittedVersion)
  • UnissResearch (Università degli Studi di Sassari) (submittedVersion)
Topics
  • Health Sciences › Medicine › Cardiology and Cardiovascular Medicine › Atrial Fibrillation Management and Outcomes
  • Health Sciences › Medicine › Cardiology and Cardiovascular Medicine › Antiplatelet Therapy and Cardiovascular Diseases
  • Health Sciences › Medicine › Epidemiology › Acute Ischemic Stroke Management
Keywords
clopidogrel, aspirin, atrial fibrillation, stroke prevention, antiplatelet therapy, vitamin K antagonists, myocardial infarction, major bleeding, vascular events, systemic embolism, anticoagulation alternatives, bleeding risk, stroke risk reduction, quality of life, cost-effectiveness
MeSH terms
Clopidogrel, Aged, Aspirin, Atrial Fibrillation, Double-Blind Method, Drug Therapy, Combination, Embolism, Female, Follow-Up Studies, Hemorrhage, Humans, Male, Middle Aged, Myocardial Infarction, Platelet Aggregation Inhibitors, Risk, Ticlopidine, Vascular Diseases, Vitamin K, Incidence, Stroke

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