IMPROVE bleeding risk score
In-hospital bleeding risk in acutely ill medical patients before thromboprophylaxis
- International IMPROVE registry
Sources last checked: 2026-10-13
IMPROVE bleeding risk score
In-hospital bleeding risk in acutely ill medical patients before thromboprophylaxis
Derived in the international IMPROVE registry of acutely ill medical inpatients; external validation shows moderate discrimination. GFR bands are as published (mL/min/m²). The score informs, but does not replace, an individual decision on prophylaxis.
Interpretation
| < 7 — lower bleeding risk | Predicted 14-day bleeding: any 1.5 %, major 0.4 % (derivation study). |
|---|---|
| ≥ 7 — high bleeding risk | Predicted 14-day bleeding: any 7.9 %, major 4.1 %. ACCP 2012 suggests mechanical rather than anticoagulant prophylaxis for medical patients at high bleeding risk. |
What is the IMPROVE bleeding risk score?
The IMPROVE bleeding risk score estimates the risk of clinically relevant bleeding during the first 14 days in hospital for acutely ill medical patients. Decousus and colleagues derived it from the international IMPROVE registry (Chest 2011), weighting eleven admission factors; a total of ≥ 7 identified a small group that accounted for a large share of major bleeding.
When to use it
- On admission of a medical patient in whom pharmacological thromboprophylaxis is considered.
- Together with a VTE risk score such as Padua to weigh benefit and harm.
- Deciding between pharmacological and mechanical prophylaxis.
When not to use it
- Surgical patients.
- Patients on therapeutic anticoagulation (use HAS-BLED or a treatment-specific bleeding score).
- As a reason to withhold prophylaxis without considering VTE risk.
How it is calculated
| Criterion | Points |
|---|---|
| Active gastroduodenal ulcer | +4.5 |
| Bleeding in the 3 months before admission | +4 |
| Platelet count < 50 × 10⁹/L | +4 |
| Age | |
| < 40 years | 0 |
| 40–84 years | 1.5 |
| ≥ 85 years | 3.5 |
| Hepatic failure (INR > 1.5) | +2.5 |
| Renal function (GFR) | |
| ≥ 60 mL/min/m² | 0 |
| 30–59 mL/min/m² (moderate renal failure) | 1 |
| < 30 mL/min/m² (severe renal failure) | 2.5 |
| ICU or CCU stay | +2.5 |
| Central venous catheter | +2 |
| Rheumatic disease | +2 |
| Current cancer | +2 |
| Sex | |
| Female | 0 |
| Male | 1 |
Clinical pearls and limitations
- Derived in the international IMPROVE registry of acutely ill medical inpatients; external validation shows moderate discrimination. GFR bands are as published (mL/min/m²). The score informs, but does not replace, an individual decision on prophylaxis.
- The three strongest factors — active gastroduodenal ulcer, bleeding in the past 3 months, platelets < 50 × 10⁹/L — each almost reach the cut-off alone.
- Age points are graded: 40–84 years 1.5, ≥ 85 years 3.5.
- Renal function bands use GFR in mL/min/m² as published.
- ACCP 2012 regarded patients with several factors or one of the three strongest as being at excessive bleeding risk.
Frequently asked questions
What IMPROVE bleeding score is high risk?
A score of 7 or more. Predicted 14-day bleeding was 7.9 % (major 4.1 %), versus 1.5 % (major 0.4 %) below 7.
Should I withhold prophylaxis if IMPROVE ≥ 7?
ACCP 2012 regarded patients at high bleeding risk as candidates for mechanical rather than anticoagulant prophylaxis, and lists correctable factors; the decision also weighs VTE risk — the score does not decide alone.
Is IMPROVE the same as HAS-BLED?
No. HAS-BLED estimates bleeding on long-term anticoagulation in atrial fibrillation; IMPROVE estimates in-hospital bleeding in medical patients considered for prophylaxis.
Evidence and guidelines
- Primary source: Decousus H et al. Factors at admission associated with bleeding risk in medical patients: findings from the IMPROVE investigators. Chest 2011;139(1):69-79.
- Arakaki D et al. External validation and update of the IMPROVE bleeding risk score. Thromb J 2024;22:31 — Table 1 reproduces the point values and the ≥ 7 cut-off.
- Kahn SR et al. Prevention of VTE in nonsurgical patients (ACCP 9th ed). Chest 2012;141(2 Suppl):e195S-e226S — IMPROVE bleeding risk factors.
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