Estimates risk of major bleeding for patients on anticoagulation to assess risk-benefit in atrial fibrillation care
Audience: PRACTITIONER
Published by EVAL Foundation
Revision 2 · Published August 21, 2026
The HAS-BLED score is a risk score to estimate the 1-year risk for major bleeding that can guide the decision to start anticoagulation in patients with atrial fibrillation.
Major bleeding is defined as any bleeding requiring hospitalization, and/or causing a decrease in hemoglobin level >2g/dL, and/or requiring blood transfusion that was not hemorrhagic stroke. (Pisters et al, 2010)
Other bleeding risk scores, such as HEMORR2HAGES and ATRIA , are often used in conjunction with HAS-BLED to determine risk of major bleeding in a patient with atrial fibrillation. To determine if the benefits of anticoagulation outweighs the risk, clinicians will compare the risk for major bleeding to the risk of thromboembolic events using the CHADS2 or CHA2DS2-VASC.
Points to keep in mind:
A modified version of the HAS-BLED score has been validated in a Japanese population. This study used different standards for hypertension and labile INR and did not include alcohol consumption.
A study comparing HEMORR₂HAGES, ATRIA and HAS-BLED showed superior performance of the HAS-BLED score compared to the other two.
Formula
Addition of the selected points:
Variable | Points |
Hypertension | 1 |
Renal disease (dialysis, transplant, Cr >2.26 mg/dL or 200 µmol/L) | 1 |
Liver disease (cirrhosis or bilirubin >2x normal with AST/ALT/AP >3x normal) | 1 |
Stroke history | 1 |
Prior major bleeding or predisposition to bleeding | 1 |
Labile INR (unstable/high INRs, time in therapeutic range <60%) | 1 |
Elderly (age >65) | 1 |
Medication usage predisposing to bleeding (aspirin, clopidogrel, NSAIDs) | 1 |
Alcohol usage (≥8 drinks/week) | 1 |
Facts and Figures
Interpretation:
HAS-BLED Score | Risk group | Risk of major bleeding** | Bleeds per 100 patient-years*** | Recommendation |
0 | Relatively low | 0.9% | 1.13 | Anticoagulation should be considered |
1 | 3.4% | 1.02 | ||
2 | Moderate | 4.1% | 1.88 | Anticoagulation can be considered |
3 | High | 5.8% | 3.72 | Alternatives to anticoagulation should be considered |
4 | 8.9% | 8.70 | ||
5 | 9.1% | 12.50 | ||
>5* | Very high | - | - |
*Scores greater than 5 were too rare to determine risk, but are likely over 10%.
**Risk figures from Lip 2011.
***Risk figures from Pisters 2010.
Current: Revision 2
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