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The HAS-BLED Score estimates the risk of major bleeding for patients on anticoagulation for atrial fibrillation (AF).

Go to the MDCalc HAS-BLED Score for Major Bleeding Risk.


  • Clinical factors that contribute to stroke risk and support anticoagulation in patients with AF are frequently risk factors for bleeding as well. The HAS-BLED score was developed as a practical risk score to estimate the one-year risk for major bleeding in patients with AF.
  • Study included 5,333 ambulatory and hospitalised patients with AF from both academic and non-academic hospitals in 35 member countries of the European Society for Cardiology:
    • Patients were followed up at one year to determine survival and major adverse cardiovascular events, such as major bleeding.
    • Major bleeding defined as any bleeding requiring hospitalisation, and/or causing a decrease in haemoglobin level >2 g/L, and/or requiring blood transfusion that was not haemorrhagic stroke.
    • Researchers performed a retrospective, univariate analysis to find potential bleeding risk factors when comparing the groups with and without major bleeding at one year follow-up.

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Disclaimer: This article is for information only and should not be used for the diagnosis or treatment of medical conditions. Egton Medical Information Systems Limited has used all reasonable care in compiling the information but make no warranty as to its accuracy. Consult a doctor or other health care professional for diagnosis and treatment of medical conditions. For details see our conditions.