CHADS2 Score
Estimates stroke risk in nonvalvular atrial fibrillation.
When to use
Historical thromboembolic risk stratification in adults with nonvalvular atrial fibrillation.
Pearls and pitfalls
- One point for heart failure, hypertension, age 75 or older and diabetes; two points for prior stroke or TIA.
- CHA2DS2-VASc and CHA2DS2-VA include additional factors and are preferred in current guidelines.
- The anticoagulation decision considers bleeding risk, kidney function, adherence and patient preference.
0/6 points
Low risk
The score does not decide anticoagulation alone; integrate bleeding risk, preferences and the current guideline.
Formula
Sum the five factors, weighting prior stroke or TIA as 2; result from 0 to 6.
Evidence
Scheme combined and validated in the National Registry of Atrial Fibrillation, with annual stroke risk rising with the score.
References
- Gage BF, Waterman AD, Shannon W, Boechler M, Rich MW, Radford MJ. Validation of clinical classification schemes for predicting stroke: results from the National Registry of Atrial Fibrillation. JAMA. 2001;285(22):2864-2870. doi:10.1001/jama.285.22.2864
Frequently asked questions
What is CHADS2 Score?
Estimates stroke risk in nonvalvular atrial fibrillation. Historical thromboembolic risk stratification in adults with nonvalvular atrial fibrillation.
How is the result calculated?
Sum the five factors, weighting prior stroke or TIA as 2; result from 0 to 6.
How should the result be interpreted?
Scheme combined and validated in the National Registry of Atrial Fibrillation, with annual stroke risk rising with the score.
What are the sources?
Gage BF, Waterman AD, Shannon W, Boechler M, Rich MW, Radford MJ. Validation of clinical classification schemes for predicting stroke: results from the National Registry of Atrial Fibrillation. JAMA. 2001;285(22):2864-2870.