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Published on: February 26, 2013
Evaluation of definitions for oral anticoagulant-associated major bleeding: A population-based cohort study
Yan Xu1, Tara Gomes2, Philip S Wells3
1Department of Medicine, University of Ottawa, Ottawa, Canada.
Insights
Major bleeding definitions from ISTH and BARC show good agreement and similar outcomes. TIMI criteria identified higher-risk patients, suggesting a need to revise bleeding definitions for better anticoagulant therapy decisions.
Area of Science:
- Cardiology
- Pharmacology
- Clinical Research
Background:
- Major bleeding is a serious complication of oral anticoagulants (OACs).
- Existing consensus criteria (ISTH, BARC, TIMI) for major bleeding definitions show variability.
- Effective OAC management requires accurate identification of major bleeding events.
Purpose of the Study:
- To evaluate the agreement between ISTH, BARC, and TIMI major bleeding definitions.
- To assess the impact of these definitions on mortality and OAC resumption.
- To inform revisions of major bleeding criteria for improved clinical decision-making.
Main Methods:
- Analysis of a dataset of elderly patients (≥66 years) in Ontario, Canada, with OAC-related bleeding (2010-2015).
- Calculation of Cohen's kappa (κ) to assess agreement between bleeding definitions.
- Multivariate regression analysis to compare mortality and OAC resumption rates across definitions.
Main Results:
- Substantial agreement was found between ISTH and BARC definitions (κ=0.69), but poor agreement with TIMI.
- ISTH, BARC, and TIMI major bleeds conferred 3.3-, 3.2-, and 5.9-fold increased 30-day mortality risk, respectively, compared to non-major bleeds.
- 180-day OAC resumption was 50% for ISTH/BARC major bleeds versus 31% for TIMI-defined major bleeds among survivors.
Conclusions:
- ISTH and BARC major bleeding criteria demonstrate good agreement and similar prognostic value.
- TIMI criteria identify a higher-risk patient group, indicating greater clinical severity.
- Revising major bleeding definitions based on predictive criteria is crucial for optimizing anticoagulant therapy and patient outcomes.
Introduction:
Major bleeding is the most serious complication of oral anticoagulants (OACs). While consensus criteria to define major bleeding have been established by the International Society for Thrombosis and Haemostasis (ISTH), Bleeding Academic Research Consortium (BARC) and Thrombolysis in Myocardial Infarction (TIMI), significant variability exists across these definitions. We sought to evaluate the agreement of cases identified by the three definitions and to assess their effect on mortality and OAC resumption.
Methods:
We used a dataset of individuals ≥66 years in Ontario, Canada presenting with OAC-related bleeding from 2010 to 2015. For case agreement, we calculated Cohen's κ between the three major bleeding definitions. We used multivariate regression to determine differences in mortality and OAC resumption among ISTH, BARC and TIMI-defined major bleeds.
Results:
Among 2002 cases of OAC-related bleeding, agreement in case identification between ISTH and BARC was substantial (Cohen's κ = 0.69); however, agreement between TIMI and other definitions were poor. Using 30-day mortality of clinically relevant non-major bleeds as comparator, ISTH-, BARC- and TIMI-defined major bleeds conferred 3.3-, 3.2- and 5.9-fold increased risk. Among survivors, 50% with ISTH- and BARC-defined major bleeds resumed OACs at 180 days, compared to 31% of TIMI-associated cases.
Conclusion:
Major bleeds identified by ISTH and BARC criteria showed good agreement and similar prognostic utility, whereas TIMI criteria identified patients at greater clinical risk. Our results highlight the need to revise major bleeding definitions based on criteria that are independently predictive of clinically relevant morbidity and mortality to more effectively reflect the risk associated with major bleeding and appropriately influence anticoagulant therapy decisions.
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