CHA2DS2-VASc score is directly associated with the risk of pulmonary embolism in patients with atrial fibrillation

Abstract

Background: The risk stratification score, which includes Congestive heart failure, Hypertension, Age ≥ 75 [doubled], Diabetes, Stroke [doubled]- Vascular disease, Age 65-74, and Sex category [female] (CHA2DS2-VASc), is used to predict stroke in atrial fibrillation. However, whether high CHA2DS2-VASc score carries a higher risk of pulmonary embolism remains unknown. We aimed to investigate the association between the severity of CHA2DS2-VASc score and the incidence of pulmonary embolism.

Methods: A total of 73,541 adults with atrial fibrillation diagnosed before January 1, 2012, and no history of pulmonary embolism, were retrospectively identified from the computerized database of the Clalit Health Services, which is the largest not-for-profit health maintenance organization in Israel. The CHA2DS2-VASc score was calculated for each subject at study entry. The cohort was followed for the first occurrence of pulmonary embolism until December 31, 2012 (70,210 person-years).

Results: Pulmonary embolism developed in 158 subjects, representing an incidence of 225.0 per 100,000 person-years. The incidence of pulmonary embolism increased with increasing CHA2DS2-VASc score (P < .001). On Cox proportional analysis, CHA2DS2-VASc score was significantly associated with pulmonary embolism (hazard ratio, 1.22; 95% confidence interval [CI], 1.13-1.32) for a 1-point increase in CHA2DS2-VASc score. The results were similar after adjusting for anticoagulants and antiplatelet use (hazard ratio, 1.24; 95% CI, 1.14-1.34), and remained unchanged after further adjustment for active malignancy. The predictive values for pulmonary embolism were similar for CHA2DS2-VASc score and the classic risk stratification score which includes Congestive heart failure, Hypertension, Age >75 years, Diabetes, and Stroke [doubled] (CHADS2); the areas under the receiver operating characteristic curves were 0.619 (95% CI, 0.579-0.660) and 0.616 (95% CI, 0.575-0.656), respectively.

Conclusions: CHA2DS2-VASc score is directly associated with the incidence of pulmonary embolism in atrial fibrillation.

Keywords: Atrial fibrillation; CHA(2)DS(2)-VASc; Mortality; Pulmonary embolism.