OBJECTIVETo compare the value between CHADS2 score and CHA2DS2-VASc score on assessing the risk of ischemic stroke in patients with nonvalvular atrial fibrillation.

METHODSIn this retrospective study, nonvalvular atrial fibrillation patients with acute ischemic stroke hospitalized from January 2004 to March 2013 in our department were included. CHADS2 score (range, 0-6) and CHA2DS2-VASc score (range, 0-9) before acute ischemic stroke was calculated. For both schemes, patients were also classified with scores of 0, 1 and ≥ 2 in low-risk, intermediated-risk and high-risk categories, respectively, the difference between the two risk stratification schemes was evaluated by each category.

RESULTSA total of 599 patients [320 men, mean age (75.4 ± 9.1) years] were collected. According to CHADS2 score, 30 (5.0%), 132 (22.0%) and 437 (73.0%) patients were classified in the low-risk, intermediated-risk and high-risk categories, respectively. The corresponding classification by CHA2DS2-VASc score was 6(1.0%), 25(4.2%) and 568 (94.8%) cases. The number of low-risk category patients (5.0% vs. 1.0%, χ(2) = 22.04, P < 0.001) and in intermediate-risk category patients (22.0% vs. 4.2%, χ(2) = 84.81, P < 0.001, Kappa = 0.075) was significantly higher in CHADS2 score group than in CHA2DS2-VASc score group, and the consistence between the two scores was poor (Kappa = 0.322). There were less patients classified in the high-risk group by CHADS2 score compared to CHA2DS2-VASc score (73.0% vs. 94.8%,χ(2) = 131.00, P < 0.001, Kappa = 0.257).

CONCLUSIONCompared with CHADS2 score, CHA2DS2-VASc score is more valuable in predicting ischemic stroke for patients with nonvalvular atrial fibrillation.