ROUNDS·
Cardio / Heme · Anticoagulation

HAS-BLED Score Calculator

Estimates major bleeding risk in patients on anticoagulation - typically used alongside CHA2DS2-VASc when weighing anticoagulation for atrial fibrillation.

Hypertension (uncontrolled, SBP > 160)+1
Abnormal renal function (dialysis, transplant, Cr > 2.26 mg/dL)+1
Abnormal liver function (cirrhosis, bilirubin >2x normal)+1
Stroke history+1
Bleeding history or predisposition+1
Labile INR (<60% time in therapeutic range)+1
Age > 65+1
Drugs predisposing to bleeding (antiplatelets, NSAIDs)+1
Alcohol excess (8+ drinks/week)+1

What is HAS-BLED?

HAS-BLED is a clinical score that estimates the risk of major bleeding in patients on long-term anticoagulation, most commonly in the context of atrial fibrillation. It was developed by Pisters and colleagues using data from the Euro Heart Survey and published in Chest in 2010. Its main practical value is identifying modifiable bleeding risk factors, like uncontrolled blood pressure or concurrent NSAID use, rather than simply flagging high-risk patients as ineligible for anticoagulation.

How to calculate HAS-BLED

Nine criteria, each worth one point (maximum 9 - note that "A" and "D" can each contribute two separate points):

Interpretation

A score of 3 or more indicates high bleeding risk. This is a flag for closer monitoring and correction of modifiable risk factors, not by itself a reason to withhold anticoagulation when there's a clear indication (e.g. a high CHA2DS2-VASc score). The two scores are designed to be used together, weighing stroke prevention against bleeding risk.

References

Pisters R, Lane DA, Nieuwlaat R, et al. A novel user-friendly score (HAS-BLED) to assess 1-year risk of major bleeding in patients with atrial fibrillation. Chest. 2010.

See also: CHA₂DS₂-VASc Calculator — used alongside HAS-BLED for anticoagulation decisions.

Frequently Asked Questions

Does a high HAS-BLED score mean anticoagulation should be stopped?

Not by itself — it flags the need for closer monitoring and correction of modifiable risk factors, and should be weighed against stroke risk (e.g. CHA2DS2-VASc), not used alone to withhold treatment.

Can 'A' or 'D' contribute more than one point each?

Yes — renal and liver dysfunction are scored separately under 'A', and drugs and alcohol are scored separately under 'D', so each letter can contribute up to two points.