Bleeding Risk in Atrial Fibrillation: HAS-BLED Score Calculator


Bleeding Risk in Atrial Fibrillation: HAS-BLED Score Calculator
Hypertension Uncontrolled, >160 mmHg systolic
Renal disease Dialysis, transplant, Cr >2.26 mg/dL or >200 µmol/L
Liver disease Cirrhosis or bilirubin >2x normal with AST/ALT/AP >3x normal
Stroke history
Prior major bleeding or predisposition to bleeding
Labile INR Unstable/high INRs, time in therapeutic range <60%
Age >65
Medication usage predisposing to bleeding Aspirin, clopidogrel, NSAIDs
Alcohol use ≥8 drinks/week

Why did the atrial fibrillation patient cross the road? Because he wanted to avoid any uncalculated bleeding risks! All humor aside, assessing your bleeding risk in atrial fibrillation is of paramount importance, and that’s where the HAS-BLED Score Calculator becomes extremely useful.

HAS-BLED Score Calculation Formula

The HAS-BLED Score Calculator helps you determine your risk of bleeding through a simple, yet effective formula:

# Hypertension: Yes = 1, No = 0
# Abnormal renal/liver function: Yes = 1/2, No = 0
# Stroke: Yes = 1, No = 0
# Bleeding history or predisposition: Yes = 1, No = 0
# Labile INR: Yes = 1, No = 0
# Elderly (>65 years): Yes = 1, No = 0
# Drugs/alcohol concomitantly: Yes = 1/2, No = 0
score = hypertension + renal/liver function + stroke + bleeding history + labile INR + elderly + drugs/alcohol

Bleeding Risk Categories

Depending upon the score you receive, you can fall into one of the three categories of risk:

Score Risk
0-1 Low
2 Moderate
3+ High

Calculation Examples

Let’s illustrate this with a couple of examples:

Example Person Hypertension Abnormal Function Stroke Bleeding History Labile INR Elderly Drugs/Alcohol Score
Bob, the 70-year-old whiskey enthusiast with a stroke history Yes No Yes No No Yes Yes 4
Alice, the 30-year-old teetotaler No No No No No No No 0

Calculation Methods

There are different ways to calculate the HAS-BLED Score:

Method Advantages Disadvantages Accuracy
Manual Accessible, no equipment needed Prone to human error Medium
App/Online Calculator Fast, accurate Requires internet access, tech High

Evolution of the HAS-BLED Score

The HAS-BLED Score has evolved over time:

Year Change
2010 Introduction of the HAS-BLED Score
2015 Validation in multiple populations
2020 Widespread adaptation in clinical practice


While the HAS-BLED Score Calculator is useful, it does have some limitations:

  1. Accuracy: It’s not 100% accurate.
  2. Individual Variation: It doesn’t account for all individual health variations.
  3. Usage: It’s not universally used or accepted.

Alternative Methods

There are also alternative methods available for assessing bleeding risk:

Method Pros Cons
ATRIA Score Includes more variables More complex
ORBIT Score Targets older patients Less studied


  1. What is the HAS-BLED Score Calculator? It’s a tool to assess bleeding risk in atrial fibrillation patients.
  2. How is the HAS-BLED Score calculated? The score is calculated using 7 variables, each worth 1 or 2 points.
  3. What does HAS-BLED stand for? HAS-BLED is an acronym for Hypertension, Abnormal renal/liver function, Stroke, Bleeding history or predisposition, Labile INR, Elderly, Drugs/alcohol concomitantly.
  4. Is the HAS-BLED Score accurate? While it provides a good estimate, it’s not 100% accurate.
  5. Can the HAS-BLED Score predict future bleeding events? It’s a risk assessment tool, not a prediction tool.
  6. Can I calculate my HAS-BLED Score at home? Yes, you can use a manual method or an online calculator.
  7. What is a good HAS-BLED Score? A score of 0-1 is considered low risk.
  8. Are there other methods to assess bleeding risk? Yes, alternative methods include the ATRIA Score and the ORBIT Score.
  9. Who should use the HAS-BLED Score Calculator? It’s primarily used by healthcare professionals, but patients can also use it to understand their risks.
  10. How often should I calculate my HAS-BLED Score? It’s best to discuss this with your healthcare provider.


  1. CDC’s Atrial Fibrillation Resources – A comprehensive source for information regarding Atrial Fibrillation.
  2. NIH’s Anticoagulant Guide – Provides guidance on the use of anticoagulants, which are often used in managing atrial fibrillation.