Cardiology

HAS-BLED Bleeding Risk Score

Q: Are NSAIDs counted?

Yes, regular NSAID use (for example, for osteoarthritis) counts toward the Drugs component. Occasional use does not.

Q: How often should it be recalculated?

At least annually, and after any significant change (new bleeding event, new medications, change in renal/hepatic function, change in blood pressure control).

Estimates annual major bleeding risk on anticoagulation for atrial fibrillation

Primary source: Pisters R et al. Chest 2010; 138(5): 1093-1100

Aleksandr A. Aulov, MD, internal medicine Last clinical review: April 28, 2026

Online calculation

Hypertension (SBP > 160 mm Hg)

Renal impairment

Dialysis, transplantation, creatinine > 200 µmol/L

Hepatic impairment

Cirrhosis, bilirubin > 2x normal, AST/ALT > 3x normal

History of stroke

Bleeding history or predisposition

Anemia, prior major bleeding, hemorrhagic diathesis

Labile INR

TTR (time in therapeutic range) < 60%

Age > 65 years

Antiplatelet agents or NSAIDs

Alcohol excess (≥ 8 drinks/week)

About this score

HAS-BLED (Pisters R, et al. Chest 2010;138:1093-1100) is a risk score for major bleeding in patients with atrial fibrillation on anticoagulant therapy. The acronym stands for Hypertension, Abnormal renal/liver function, Stroke (history), Bleeding (history or predisposition), Labile INR, Elderly (age > 65 years), and Drugs/alcohol (antiplatelet agents/NSAIDs or alcohol excess).

Each component contributes 1 point (renal and liver impairment are scored separately, up to 2 points total), for a total range of 0-9. A score ≥ 3 indicates high risk of major bleeding (≥ 3.7 per 100 patient-years). The 2020 ESC guidelines on atrial fibrillation recommend HAS-BLED as the standard bleeding risk assessment tool.

Key concept: a HAS-BLED score ≥ 3 is not a contraindication to anticoagulation. The score is used to identify modifiable risk factors (hypertension, labile INR, drug interactions, alcohol use) that can be addressed, and to guide closer monitoring in high-risk patients.

When to use

Before starting anticoagulation in a patient with atrial fibrillation, to identify modifiable factors and plan monitoring.
During ongoing anticoagulation, for annual reassessment alongside CHA2DS2-VASc.
Choice of agent (for example, apixaban has a better safety profile in high-risk patients).
Documenting the clinical rationale for anticoagulation in a patient with high bleeding risk.

Clinical example

Case

72-year-old man with paroxysmal atrial fibrillation. Grade 3 hypertension, creatinine 180 µmol/L, history of hemorrhoidal bleeding one year ago, taking aspirin 75 mg for coronary artery disease. Moderate alcohol use. CHA2DS2-VASc = 4.

Calculation

Hypertension (+1) + Renal (+1) + Bleeding (+1) + Elderly > 65 (+1) + Drugs aspirin (+1) = 5 points.

Interpretation and management

High bleeding risk. Management: anticoagulation is still indicated (CHA2DS2-VASc 4). Modifiable factors: control hypertension; reassess the need for aspirin; choose a DOAC with a better safety profile (apixaban 5 mg twice daily). Increase monitoring: fecal occult blood testing every 6 months, reassess DOAC dosing if renal function changes.

Limitations and cautions

A high score alone is not a contraindication to anticoagulation, it signals the need to address modifiable risk factors.
Does not distinguish between DOACs and warfarin, which have different safety profiles.
Overestimates risk in patients with severe CKD on hemodialysis.
Not designed to predict intracranial bleeding specifically; dedicated scores exist for that purpose.

Frequently asked questions

Can anticoagulation be withheld when HAS-BLED ≥ 3?

No, a high score alone is not a contraindication. Anticoagulation should be prescribed with attention to modifiable risk factors and selection of a safer regimen (apixaban).

What counts as a 'labile INR'?

Time in therapeutic range (TTR) < 60% over the preceding 6 months. This component applies only to warfarin; it is not scored for DOACs.

Are NSAIDs counted?

Yes, regular NSAID use (for example, for osteoarthritis) counts toward the Drugs component. Occasional use does not.

How often should it be recalculated?

At least annually, and after any significant change (new bleeding event, new medications, change in renal/hepatic function, change in blood pressure control).

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Aleksandr A. Aulov Physician, internal medicine, Sechenov School — independent medical education platform. Calculators are compiled from the original publications and current clinical guidelines. Interpretation thresholds follow the source study unless stated otherwise.

This calculator is intended for healthcare professionals. Do not use it for self-diagnosis or self-treatment. Management decisions are made by the treating clinician based on the full clinical picture of the individual patient.