Table 2.
Predicted risk of stroke and systemic thromboembolism by CHADS2 and CHA2DS2-VASc score at baseline and observed stroke risk over 12-month follow-up
| Score | CHA2DS2-VASc score | CHADS2 score | ||
|---|---|---|---|---|
|
|
|
|||
| n (%) | Observed stroke rate n (%) | n (%) | Observed stroke rate n (%) | |
| 0 | 119 (5.3) | 1 (0.8) | 325 (14) | 1 (0.3) |
| 1 | 205 (9.1) | 0 | 535 (24) | 6 (1.1) |
| 2 | 321 (14) | 2 (0.6) | 678 (30) | 15 (2.2) |
| 3 | 483 (21) | 5 (1.0) | 367 (16) | 12 (3.3) |
| 4 | 492 (22) | 17 (3.5) | 240 (11) | 23 (9.6) |
| 5 | 321 (14) | 17 (5.3) | 98 (4.4) | 9 (9.2) |
| 6 | 205 (9.1) | 14 (6.8) | 16 (0.7) | 1 (6.3) |
| 7 | 96 (4.3) | 10 (10.4) | NA | NA |
| 8 | 16 (0.7) | 0 | NA | NA |
| 9 | 1 (<0.1) | 1 (100) | NA | NA |
| Low riska | 170 (7.5) | 1 (0.6) | 325 (14) | 1 (0.3) |
| Moderate or high riskb | 2089 (92.5) | 66 (3.2) | 1934 (86) | 66 (3.4) |
NA, not applicable. CHADS2 score, C = recent congestive heart failure, H = hypertension, A = age ≥75 years, D = diabetes mellitus, S = stroke/transient ischaemic attack (TIA); 2 points for presence of stroke/TIA and 1 point for presence of each other risk factor.4 CHA2DS2-VASc score, C = congestive heart failure, H = hypertension, A = age ≥75 years, D = diabetes mellitus, S = stroke/TIA, V = vascular disease (peripheral arterial, myocardial infarction, or aortic plaque), A = age 65–74 years, and Sc = sex category (female); 2 points each for age ≥75 or previous stroke/TIA and 1 point for presence of each other risk factor.13
Low risk by CHA2DS2-VASc score = 0 for males and 1 for females.
Moderate or high risk denotes a CHADS2 score ≥1 or a CHA2DS2-VASc score ≥1 (males) and ≥2 (females).