What HAS-BLED is for
People with atrial fibrillation often take an anticoagulant to prevent strokes. The trade-off is a higher risk of bleeding. HAS-BLED, published by Pisters and colleagues in 2010 from the Euro Heart Survey, estimates that bleeding risk with nine simple items, each worth one point.
The nine items
| Letter | Item | Points |
|---|---|---|
| H | Uncontrolled hypertension, systolic above 160 mmHg | 1 |
| A | Abnormal kidney function: dialysis, transplant, creatinine ≥ 2.26 mg/dL | 1 |
| A | Abnormal liver function: cirrhosis, or bilirubin > 2× and liver enzymes > 3× normal | 1 |
| S | Prior stroke | 1 |
| B | Prior major bleeding or a bleeding tendency such as anemia | 1 |
| L | Labile INR, time in therapeutic range below 60% (warfarin users) | 1 |
| E | Elderly, over 65 | 1 |
| D | Drugs: antiplatelets or NSAIDs | 1 |
| D | Alcohol, 8 or more drinks a week | 1 |
Worked example
A 72-year-old with blood pressure that stays above 160 mmHg and no other items:
- H: 1 point; E: 1 point.
- Total: 2 points, a moderate bleeding risk.
- In the original cohort, a score of 2 matched about 1.88 major bleeds per 100 patient-years.
Bleeding rates by score
| Score | Major bleeds per 100 patient-years |
|---|---|
| 0 | 1.13 |
| 1 | 1.02 |
| 2 | 1.88 |
| 3 | 3.74 |
| 4 | 8.70 |
| 5 | 12.50 |
These figures come from a single cohort; rates in other populations differ, but the trend holds.
How the score is used
A score of 3 or more flags a high bleeding risk. Current guidelines do not use it as a reason to withhold anticoagulation, because the stroke risk usually outweighs the bleeding risk. Instead, the score points to factors that can be fixed: bringing blood pressure under control, stopping unneeded aspirin or NSAIDs, reducing alcohol and improving INR control or switching to a direct oral anticoagulant. The calculator counts these modifiable items separately.
Related scores
HAS-BLED is used alongside CHA₂DS₂-VASc, which estimates stroke risk. The two scores share several items, such as age, hypertension and prior stroke, which shows how closely stroke and bleeding risks are linked.
This calculator is for general information and education. It is not medical advice and does not replace the judgment of a doctor, nurse or pharmacist who knows the full clinical picture.