HAS-BLED Major Bleeding Risk Score

Estimates 1-year risk of major bleeding on anticoagulation in atrial fibrillation. A score ≥3 flags high risk and modifiable factors — it should prompt review, not automatically stop anticoagulation.

H Hypertension (uncontrolled, SBP >160) +1 · A Abnormal renal/liver function (1 each) +2 · S Stroke history +1 · B Bleeding history/predisposition +1 · L Labile INR (TTR <60%) +1 · E Elderly >65 +1 · D Drugs (antiplatelet/NSAID) or alcohol (1 each) +2 0 low · 1–2 moderate · ≥3 high risk (~3.74+ bleeds/100 patient-years) → address modifiable factors and closer follow-up

Published Clinical Benchmark Cases

Clinical Parameters & Inputs

Uncontrolled hypertension (SBP >160 mmHg)? [+1]

Abnormal renal function (dialysis, Cr ≥200, transplant)? [+1]

Abnormal liver function (cirrhosis, bilirubin >2×, enzymes >3×)? [+1]

Prior stroke? [+1]

Bleeding history or predisposition (anaemia)? [+1]

Labile INR (TTR <60%, if on warfarin)? [+1]

Elderly (age >65)? [+1]

Concomitant antiplatelet / NSAID? [+1]

Excess alcohol (≥8 units/week)? [+1]

Computed OutputLow Risk (Score 0)

0points

Diagnostic Interpretation

HAS-BLED is 0 (Low Risk, ~1.13 major bleeds/100 patient-years). Anticoagulate if the stroke-risk score (CHA₂DS₂-VASc) indicates.

Calculation Breakdown

HAS-BLED Sum

Count of positive risk factors =0 / 9 points

Risk Band

0 low · 1–2 moderate · ≥3 high =Low Risk (Score 0)

Clinical Decision Pearls

A high HAS-BLED is a prompt to optimize modifiable bleeding risks and monitor, not a reason to deny a high-CHA₂DS₂-VASc patient anticoagulation.
Ensure baseline and annual hemoglobin, renal and hepatic function for anyone on long-term anticoagulation.

Limitations & Confounders

Originally derived/validated on warfarin cohorts; extrapolation to DOACs is indirect but widely used.
Many modifiable components (uncontrolled BP, NSAIDs, alcohol) mean the score should be recalculated after intervention.

Evidence & Citations

Pisters R, Lane DA, Nieuwlaat R, de Vos CB, Crijns HJGM, Lip GYH. A novel user-friendly score (HAS-BLED) to assess 1-year risk of major bleeding in patients with atrial fibrillation. Chest. 2010;138(5):1093-1100.