Anticoagulant activity of apixaban can be estimated by multiple regression analysis

Abstract

Background: Information on apixaban anticoagulant activity is required to prevent major bleeding or thrombosis during its use. Methods: We enrolled 194 patients with nonvalvular atrial fibrillation (NVAF) in whom warfarin was replaced with apixaban: 105 (54.1%) received the standard dose of apixaban (5 mg twice daily [BID]; 5 mg group) and 89 (45.9%) received a reduced dose (2.5 mg BID; 2.5 mg group). Multiple regression analysis was performed to predict the prothrombin time of apixaban (PTa) based on factors including age, body weight (BW), serum creatinine, and CHA2DS2-VASc score. Results: PTa and PT of warfarin (PTw) were significantly correlated in both groups (correlation coefficient R = 0.239 [P =.014] in the 5 mg group; R = 0.248 [P =.019] in the 2.5 mg group). PTa in the 5 mg group was predicted as follows: 16.952-0.036 × BW +0.299 × CHA2DS2-VASc score (P