Frequency and predictors of bleeding complications associated with anti-coagulant therapy using dabigatran in Japanese patients with atrial fibrillation.

BACKGROUND Few data exist regarding frequency and predictors of bleeding complications associated with anticoagulant therapy using dabigatran in Japanese patients with atrial fibrillation (AF). METHODS AND RESULTS We retrospectively studied 184 patients with AF who were administered dabigatran from April 2011 to August 2012 in our institution. Twenty-eight patients (15%) developed some type of bleeding complication. In the Bleeding group, age, CHADS2 and HAS-BLED score were higher (75 vs. 71 years, p=0.067, 2.7 vs. 1.9, p=0.006 and 2.3 vs. 1.8, p=0.01, respectively), hemoglobin concentration was lower (13.1 vs. 13.7 g/dL, p=0.04), casual activated partial thromboplastin time (APTT) was longer (60.2 vs. 47.4 sec., p<0.0001) and frequency of aspirin use was higher (29 vs. 15%, p=0.09) than those in the Non-bleeding group. Multivariate regression analysis showed that casual APTT was an independent significant predictor of any type of bleeding complications (β=0.431, p<0.0001). Moreover, casual APTT (β=0.359, p=0.049), pre-existing anemia (β=0.457, p=0.02) and aspirin use (β=0.597, p=0.02) were significant predictors of major bleeding. ROC analysis showed that casual APTT exhibited 83.3% sensitivity and 72.5% specificity as predictors of major bleeding and its cut-off value was 54.7 sec. CONCLUSION Casual APTT level can serve as a predictor of bleeding complications, while pre-existing anemia and aspirin use may be associated with major bleeding in patients with AF treated with dabigatran.