# HAS-BLED Score (Major Bleeding Risk)

Calculate the HAS-BLED score to estimate major bleeding risk in patients on oral anticoagulation (most commonly combined with CHA₂DS₂-VASc in atrial fibrillation). Each component scores 1 point: Hypertension (uncontrolled, systolic BP >160), Abnormal renal function (dialysis/transplant/Cr >2.26 mg/dL), Abnormal liver function, prior Stroke, prior major Bleeding/predisposition, Labile INR (TTR <60% on warfarin), Elderly (age >65), Drugs (antiplatelet/NSAID), Alcohol (≥8 drinks/week). Range 0–9 (renal/liver and drugs/alcohol can each contribute up to 2). Interpretation: 0 low, 1–2 moderate, ≥3 high risk — regular review and correct reversible factors; a high score alone does NOT justify withholding anticoagulation. Derived from Pisters 2010 (Chest) and the 2023 ACC/AHA/ACCP/HRS AF guideline. The 'labile INR' criterion mainly applies to warfarin users; predictive value is lower for DOACs. Not medical advice.

> Canonical page: https://elysiatools.com/en/tools/has-bled-score

- **Category:** Health

- **Keywords:** HAS-BLED, bleeding risk, anticoagulation, warfarin, DOAC, atrial fibrillation, AFib, major bleeding, cardiology, hemorrhage

## Overview

The HAS-BLED Score calculator estimates major bleeding risk in patients taking oral anticoagulants. Select the applicable clinical factors to calculate a score from 0 to 9 and view the corresponding risk category: low, moderate, or high.

## Inputs

- **Hypertension** (checkbox): Uncontrolled hypertension, systolic BP > 160 mmHg. +1.
- **Abnormal renal function** (checkbox): Chronic dialysis, renal transplant, or serum Cr > 2.26 mg/dL (>200 µmol/L). +1.
- **Abnormal liver function** (checkbox): Chronic hepatic disease, or bilirubin > 2× ULN with AST/ALT/ALP > 3× ULN. +1.
- **Prior stroke** (checkbox): Prior stroke history. +1.
- **Prior major bleeding / predisposition** (checkbox): Prior major bleeding or predisposition to bleeding. +1.
- **Labile INR (TTR < 60% on warfarin)** (checkbox): Unstable/high INRs or time-in-therapeutic-range < 60% on warfarin. +1. Mainly applies to warfarin users.
- **Age > 65 years** (checkbox): Age > 65 years. +1.
- **Drugs (antiplatelet / NSAID)** (checkbox): Concomitant antiplatelet agent or NSAID use. +1.
- **Alcohol (≥ 8 drinks/week)** (checkbox): Excess alcohol intake (≥ 8 drinks/week). +1.

## When to use

- Assess bleeding risk in a patient receiving oral anticoagulation, especially for atrial fibrillation.
- Review modifiable bleeding risk factors such as uncontrolled hypertension, NSAID use, or excess alcohol intake.
- Support a broader anticoagulation review alongside stroke-risk assessment and clinical judgment.

## How it works

- Select each applicable HAS-BLED factor, including hypertension, renal or liver dysfunction, prior stroke, bleeding history, labile INR, age over 65, drugs, and alcohol.
- The calculator assigns points to the selected factors and adds them to produce the total score.
- The result categorizes the score as low, moderate, or high bleeding risk.
- Use the result to identify factors for review; a high score alone does not justify withholding anticoagulation.

## Use cases

- Cardiology and atrial fibrillation reviews where bleeding risk is considered alongside CHA₂DS₂-VASc.
- Anticoagulation clinics reviewing warfarin control, medication use, and modifiable risk factors.
- Clinical education and documentation of the factors contributing to a bleeding-risk assessment.

## Frequently asked questions

### What does the HAS-BLED Score measure?

It estimates the risk of major bleeding in patients taking oral anticoagulants.

### What is the HAS-BLED score range?

The score ranges from 0 to 9.

### How is the HAS-BLED score interpreted?

A score of 0 is low risk, 1–2 is moderate risk, and 3 or higher is high risk.

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

No. A high score calls for regular review and correction of reversible factors, but does not by itself justify stopping anticoagulation.

### Does the labile INR criterion apply to DOAC users?

It mainly applies to patients taking warfarin; its predictive value is lower for DOACs.

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