💗 CHADS₂ Atrial Fibrillation Stroke Risk
CHADS₂ is the original simplified score for estimating annual stroke risk in non-valvular atrial fibrillation.
Clinical takeaway
A score ≥2 generally favors oral anticoagulation, but contemporary guidelines prefer the finer CHA₂DS₂-VASc, especially at low scores (original synthesis · not guideline verbatim).
Loading calculator…
Paste the link in Slack, Teams, X, or LinkedIn — the preview image comes from this page’s Open Graph card.
When to use
Select each risk factor; the tool sums the points (0–6) and reports the annual stroke risk band.
How it works
CHADS₂ = congestive heart failure (1) + hypertension (1) + age ≥75 (1) + diabetes (1) + prior stroke/TIA (2). Annual stroke risk rises from ~1.9% at 0 to ~18.2% at 6.
Key points
- A score ≥2 generally favors oral anticoagulation, but contemporary guidelines prefer the finer CHA₂DS₂-VASc, especially at low scores (original synthesis · not guideline verbatim).
- Anticoagulation decisions should also weigh bleeding risk using HAS-BLED or ORBIT.
- CHADS₂ underestimates risk in some 'low-risk' patients that CHA₂DS₂-VASc reclassifies upward via sex, vascular disease, and age 65–74.
References
- Gage BF, et al. Validation of clinical classification schemes for predicting stroke (CHADS₂). JAMA. 2001.
- Joglar JA, et al. 2023 ACC/AHA/ACCP/HRS Guideline for the Diagnosis and Management of Atrial Fibrillation. Circulation. 2024.
Decision support for licensed clinicians only; not a substitute for clinical judgement, diagnosis or local protocols.
Worked calculation
The values below come from this tool's own example placeholders and are computed server-side with the formula shown on this page, so the arithmetic can be checked quickly. It demonstrates how to substitute values only — it is not clinical advice and not a real case.
| Congestive heart failure | No |
|---|---|
| Hypertension | No |
| Age ≥75 | No |
| Diabetes mellitus | No |
| Prior stroke/TIA/thromboembolism | No |
→CHADS₂0/6 · annual stroke risk ~1.9% (Low risk)
- Components：HF +1, hypertension +1, age ≥75 +1, diabetes +1, prior stroke/TIA +2.
- Annual stroke risk：0≈1.9% · 1≈2.8% · 2≈4.0% · 3≈5.9% · 4≈8.5% · 5≈12.5% · 6≈18.2% (Gage 2001).
- Management direction：CHADS₂ ≥2 generally favors oral anticoagulation; guidelines now mostly recommend the finer CHA₂DS₂-VASc (especially for low scores), then weigh bleeding risk (HAS-BLED/ORBIT).
| Congestive heart failure | Yes (+1) |
|---|---|
| Hypertension | Yes (+1) |
| Age ≥75 | Yes (+1) |
| Diabetes mellitus | Yes (+1) |
| Prior stroke/TIA/thromboembolism | Yes (+2) |
→CHADS₂6/6 · annual stroke risk ~18.2% (Moderate–high risk)
- Components：HF +1, hypertension +1, age ≥75 +1, diabetes +1, prior stroke/TIA +2.
- Annual stroke risk：0≈1.9% · 1≈2.8% · 2≈4.0% · 3≈5.9% · 4≈8.5% · 5≈12.5% · 6≈18.2% (Gage 2001).
- Management direction：CHADS₂ ≥2 generally favors oral anticoagulation; guidelines now mostly recommend the finer CHA₂DS₂-VASc (especially for low scores), then weigh bleeding risk (HAS-BLED/ORBIT).
Frequently asked questions
- What is CHADS₂ Atrial Fibrillation Stroke Risk?
- CHADS₂ is the original simplified score for estimating annual stroke risk in non-valvular atrial fibrillation.
- How is CHADS₂ Atrial Fibrillation Stroke Risk calculated? What is the core formula?
- CHADS₂ = congestive heart failure (1) + hypertension (1) + age ≥75 (1) + diabetes (1) + prior stroke/TIA (2). Annual stroke risk rises from ~1.9% at 0 to ~18.2% at 6.
- When is CHADS₂ Atrial Fibrillation Stroke Risk used?
- Select each risk factor; the tool sums the points (0–6) and reports the annual stroke risk band.
- What are the key clinical points for CHADS₂ Atrial Fibrillation Stroke Risk?
- A score ≥2 generally favors oral anticoagulation, but contemporary guidelines prefer the finer CHA₂DS₂-VASc, especially at low scores (original synthesis · not guideline verbatim). Anticoagulation decisions should also weigh bleeding risk using HAS-BLED or ORBIT. CHADS₂ underestimates risk in some 'low-risk' patients that CHA₂DS₂-VASc reclassifies upward via sex, vascular disease, and age 65–74.
- What are the limits and cautions when using CHADS₂ Atrial Fibrillation Stroke Risk?
- For licensed clinicians and clinical researchers. Interpret results with history, investigations and local protocols; not a diagnosis or prescription, and not a substitute for multidisciplinary decision-making or local guidelines.
- How is CHADS₂ Atrial Fibrillation Stroke Risk calculated in practice? Can you show a worked example?
- Inputs: Congestive heart failure No, Hypertension No, Age ≥75 No, Diabetes mellitus No, Prior stroke/TIA/thromboembolism No → Result: CHADS₂ 0 /6 · annual stroke risk ~1.9% (Low risk)（Components: HF +1, hypertension +1, age ≥75 +1, diabetes +1, prior stroke/TIA +2., Annual stroke risk: 0≈1.9% · 1≈2.8% · 2≈4.0% · 3≈5.9% · 4≈8.5% · 5≈12.5% · 6≈18.2% (Gage 2001)., Management direction: CHADS₂ ≥2 generally favors oral anticoagulation; guidelines now mostly recommend the finer CHA₂DS₂-VASc (especially for low scores), then weigh bleeding risk (HAS-BLED/ORBIT).） Inputs: Congestive heart failure Yes (+1), Hypertension Yes (+1), Age ≥75 Yes (+1), Diabetes mellitus Yes (+1), Prior stroke/TIA/thromboembolism Yes (+2) → Result: CHADS₂ 6 /6 · annual stroke risk ~18.2% (Moderate–high risk)（Components: HF +1, hypertension +1, age ≥75 +1, diabetes +1, prior stroke/TIA +2., Annual stroke risk: 0≈1.9% · 1≈2.8% · 2≈4.0% · 3≈5.9% · 4≈8.5% · 5≈12.5% · 6≈18.2% (Gage 2001)., Management direction: CHADS₂ ≥2 generally favors oral anticoagulation; guidelines now mostly recommend the finer CHA₂DS₂-VASc (especially for low scores), then weigh bleeding risk (HAS-BLED/ORBIT).）