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    HAS-BLED Score for Major Bleeding Risk

    Estimates risk of major bleeding for patients on anticoagulation to assess risk-benefit in atrial fibrillation care.
    When to Use
    Why Use
    • Consider using the HAS-BLED Score as a tool to potentially guide the decision to start anticoagulation in patients with atrial fibrillation.
    • Consider using the HAS-BLED Score instead of, or in conjunction with, other bleeding risk scores such as HEMORR2HAGES and ATRIA to determine risk of major bleeding in a patient with atrial fibrillation.
    • Consider comparing the risk for major bleeding as calculated by the HAS-BLED Score to the risk for thromboembolic events by the CHADS2 or CHA2DS2-VASc to determine if the benefit of anticoagulation outweighs the risk.

    Clinical factors that contribute to stroke risk and support anticoagulation in patients with atrial fibrillation are frequently risk factors for bleeding as well. The HAS-BLED Score was developed as a practical risk score to estimate the 1-year risk for major bleeding in patients with atrial fibrillation.
    Study included 5,333 ambulatory and hospitalized 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 hospitalization, and/or causing a decrease in hemoglobin level > 2 g/L, and/or requiring blood transfusion that was not hemorrhagic stroke.
    • Researchers performed a retrospective, univariate analysis to find potential bleeding risk factors when comparing the groups with and without major bleeding at 1 year follow-up.
    • Developed HAS-BLED score based on results of their analysis as well as known significant risk factors for major bleeding
    • Results showed that the annual bleeding rate increased with increasing risk factors, with an overall major bleed rate of 1.5%.

    Points to keep in mind:

    • Study only provides risk percentages for given risk factor, does not categorize scores into low/medium/high risk
    • HAS-BLED score, in the form that it was developed originally, still needs to be externally validated
    • 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.

    The HAS-BLED Score can guide the decision to start anticoagulation in patients with atrial fibrillation.


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    Next Steps
    Creator Insights

    Critical Actions

    Patient specific risks and benefits of anticoagulation must be carefully weighed in all patients who are potential candidates for long-term anticoagulation therapy.


    Addition of the selected points, see below:

    Facts & Figures

    Risk Factor 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

    Note: HAS-BLED is an acronym for Hypertension, Abnormal liver/renal function, Stroke history, Bleeding predisposition, Labile INR, Elderly, Drug/alcohol usage.

    Dr. Ron Pisters

    From the Creator

    Why did you develop the HAS-BLED score? Was there a clinical experience that inspired you to create this tool for clinicians?
    Increasing awareness of the evidence that oral anticoagulation is a necessity in the vast majority of atrial fibrillation (AF) patients, outdated paradigms to withhold anticoagulation (e.g. fall risk) and a lacking user-friendly counterpart to stroke risk assessment (e.g. CHA2DS2-VASc) despite the inherent (antithrombotic drug related) risk of bleeding led us to develop the HAS-BLED score.
    What pearls, pitfalls and/or tips do you have for users of the HAS-BLED score? Are there cases when it has been applied, interpreted, or used inappropriately?
    The most important pitfall is using HAS-BLED as an absolute cut-off to withhold or withdraw anticoagulation. Keep in mind that in the vast majority of AF patients risk of stroke (and associated outcome) outweighs risk of bleeding. Instead, HAS-BLED should be used as an alarmbell which assists in minimizing the potential risk of bleeding by signaling risk factors that can be avoided or reversed. Both important to note and as a good example of the alarmbell function is that the ”H” in HAS-BLED (opposed to the stroke risk equivalent) does not stand for history of hypertension but refers to the actual systolic blood pressure (≥160 mmHg scores 1 point). Thus, explain the importance of blood pressure control and actively lower it accordingly to reverse it as risk factor for major bleeding, i.e. lose 1 HAS-BLED point and lower the bleeding risk (whereas the risk of stroke remains the same!).
    What recommendations do you have for health care providers once they have the HAS-BLED score result? Are there any adjustments or updates you would make to the score given recent changes in medicine?
    Antithrombotic management is not about a single, simple decision to initiate antithrombotic drugs or not. Antithrombotic management is all about the continuous balancing of risk (assessment) and communication. HAS-BLED is an easy-to-use tool capable of both when it comes to the risk of major bleeding of your AF patients.

    About the Creator

    Ron Pisters, MD, PhD, is an internal medicine resident at Atrium Medical Center Parkstad in the Netherlands. Previously, he worked as a clinical research fellow, focusing on atrial fibrillation, under the supervision of Harry JGM Crijns at the Department of Cardiology, University of Maastricht. Dr. Pisters' research interests include antithrombotic management of patients with atrial fibrillation and assessing the individualised risk of embolic and bleeding events.

    To view Dr. Ron Pisters's publications, visit PubMed

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    About the Creator
    Dr. Ron Pisters
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