Direct oral anticoagulant users had a lower baseline risk of stroke (CHADS2 score 0-1 in 46.9% vs 39.4%) compared to warfarin users, and inappropriate low dosing was observed in 19.7-27.6% of DOAC users.
Observational (n=3,266)
Yes
Are there differences in patient characteristics and dosing appropriateness between DOAC and warfarin users in Japanese patients with atrial fibrillation?
In real-world Japanese practice, DOACs are preferentially prescribed to AF patients with lower stroke risk and better renal function compared to warfarin, but inappropriate low-dosing of DOACs (20-30%) and under-dosing of warfarin (32%) are highly prevalent.
Absolute Event Rate: 46.9% vs 39.4%
p-value: p=<0.0001
Abstract Background Large‐scale investigations on the use of oral anticoagulants including direct oral anticoagulants (DOACs) in patients with atrial fibrillation (AF) have not included Japanese patients. Methods We established the multicenter SAKURA AF Registry to support prospective observational research on the status of anticoagulation treatment, especially with DOAC, for AF in Japan. We enrolled 3266 AF patients treated with warfarin ( n =1577) or any of 4 DOACs ( n =1689) from 63 institutions (2 cardiovascular centers, 13 affiliated hospitals or community hospitals, and 48 private clinics) in the Tokyo area. Results We conducted our first analysis of the registry data, and although we found equivalent mean age between the DOAC and warfarin users (71.8±9.5 vs. 72.3±9.4 years, p =0.2117), we found a slightly lower risk of stroke (CHADS 2 score of 0 or 1 46.9% vs. 39.4%, p <0.0001) and significantly better creatinine clearance in DOAC users (70.4±27 vs. 65.6±25.7 mL/min, p <0.0001). Importantly, we documented under‐dosing in 32% of warfarin users and inappropriate‐low‐dosing in 19.7–27.6% of DOAC users. Conclusions Our initial analysis of the SAKURA AF Registry data clarified the real‐world use of anticoagulants, which includes DOACs and warfarin in Japan. The DOAC users were at a lower risk for stroke than the warfarin users. In 20–30% of DOAC users, the dose was inappropriately reduced.
Okumura et al. (2017) conducted an observational in Atrial fibrillation (n=3,266). Direct oral anticoagulants (DOACs) vs. Warfarin was evaluated on CHADS2 score of 0 or 1 (lower risk of stroke) (p=<0.0001). Direct oral anticoagulant users had a lower baseline risk of stroke (CHADS2 score 0-1 in 46.9% vs 39.4%) compared to warfarin users, and inappropriate low dosing was observed in 19.7-27.6% of DOAC users.