HAS-BLED
Major bleeding risk on anticoagulation
- Euro Heart Survey derivation
- ESC 2020 AF guideline
Sources last checked: 2026-10-13
HAS-BLED
Major bleeding risk on anticoagulation
Bleeding risk on its own is not an argument against anticoagulation (ESC 2024); modifiable bleeding risk factors remain relevant at any score.
Designed to make modifiable bleeding risk visible — not to refuse anticoagulation. Most of the factors it counts are also stroke risk factors.
Interpretation
| 0–2 — lower risk | Bleeding risk on its own is not an argument against anticoagulation (ESC 2024); modifiable bleeding risk factors remain relevant at any score. |
|---|---|
| ≥ 3 — high risk | ESC 2020 uses a score ≥ 3 to flag modifiable risk factors and earlier, more frequent review. ESC 2024: a high score is NOT a reason to withhold anticoagulation (class III). |
What is the HAS-BLED?
HAS-BLED estimates the one-year risk of major bleeding in patients with atrial fibrillation on anticoagulation. Pisters and colleagues derived it in 2010 from 3,978 patients in the Euro Heart Survey on AF. Each of nine items scores 1 point (maximum 9); a score of 3 or more marks high bleeding risk.
When to use it
- When starting oral anticoagulation in atrial fibrillation, to identify modifiable bleeding risk factors.
- At follow-up, to flag patients with a score ≥ 3 for earlier and more frequent review.
- When structuring a medication review: concomitant antiplatelets, NSAIDs, labile INR and alcohol are all correctable items.
When not to use it
- As a reason to withhold or stop anticoagulation — ESC 2024 explicitly recommends against using bleeding scores for that decision (class III).
- Outside atrial fibrillation (e.g. venous thromboembolism), where it was not derived and other bleeding scores are used.
- In active bleeding — the score is a planning tool, not an acute assessment.
How it is calculated
| Criterion | Points |
|---|---|
| Uncontrolled hypertension (systolic > 160 mmHg) | +1 |
| Abnormal renal function (dialysis, transplant, creatinine > 200 µmol/L) | +1 |
| Abnormal liver function (cirrhosis, bilirubin > 2×, AST/ALT > 3×) | +1 |
| Prior stroke | +1 |
| Bleeding history or predisposition | +1 |
| Labile INR (time in therapeutic range < 60%) | +1 |
| Age > 65 | +1 |
| Drugs that increase bleeding (antiplatelets, NSAIDs) | +1 |
| ≥ 8 units of alcohol per week | +1 |
Clinical pearls and limitations
- Designed to make modifiable bleeding risk visible — not to refuse anticoagulation. Most of the factors it counts are also stroke risk factors.
- ESC 2024 does not recommend any specific bleeding score because of modest predictive ability; the 2020 ESC guideline had suggested HAS-BLED (class IIa) to address modifiable factors.
- Most HAS-BLED items (hypertension, age, prior stroke) also raise stroke risk, so a high score usually means a larger net benefit from anticoagulation, not a smaller one.
- The correctable items are uncontrolled blood pressure, unnecessary antiplatelets/NSAIDs, alcohol intake and a labile INR on a vitamin K antagonist.
- 'Labile INR' only applies to vitamin K antagonists (time in therapeutic range < 60 %); score it 0 for patients on a DOAC.
- Renal threshold in the original score is in µmol/L (creatinine ≈ 200 µmol/L ≈ 2.26 mg/dL), reflecting its European derivation.
Frequently asked questions
Is a HAS-BLED score of 3 a contraindication to anticoagulation?
No. A score ≥ 3 means higher bleeding risk; ESC 2020 links it to addressing modifiable factors and closer follow-up. ESC 2024 states that bleeding risk scores should not be used to decide on starting or withdrawing anticoagulation, because stroke risk without anticoagulation usually outweighs bleeding risk.
HAS-BLED vs ORBIT — which bleeding score is better?
Both have only modest discrimination in validation studies. ESC 2024 does not prefer one; what matters clinically is identifying and correcting modifiable risk factors.
Does HAS-BLED apply to patients on DOACs?
It was derived mostly in patients on vitamin K antagonists or antiplatelets, but it is widely used for DOAC-treated patients. Score the labile-INR item as 0 if the patient is not on a VKA.
Evidence and guidelines
- Primary source: Pisters R et al. A novel user-friendly score (HAS-BLED) to assess 1-year risk of major bleeding in patients with atrial fibrillation: the Euro Heart Survey. Chest 2010;138(5):1093-1100.
- Hindricks G et al. 2020 ESC Guidelines for the diagnosis and management of atrial fibrillation. Eur Heart J 2021;42(5):373-498 — HAS-BLED ≥ 3 to flag patients for early and more frequent review (class IIa).
- Van Gelder IC et al. 2024 ESC Guidelines for the management of atrial fibrillation. Eur Heart J 2024;45(36):3314-3414 — no specific bleeding score recommended; scores must not be used to start or withdraw anticoagulation (class III).
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