The Anticoagulant Efficacy Of Weekly-dosage Strategies Of Warfarin Prescription In Patients With Non-valvular Atrial Fibrillation

Aim:To evaluate the anticoagulant efficacy of warfarin considering two different administration strategies in patients with non-valvular atrial fibrillation.Method:The patients with non-valvular atrial fibrillation and CHA2DS2-VASc score ≥2points(female CHA2DS2-VASc score≥3 points)were recruited in Ningbo First Hospital,China,from January 2015 to January 2019.If international normalized ratio(INR)did not meet the standard after initial warfarin empirical treatment(1-3mg per day)for one week,the patients were then randomly assigned to weekly-dosage strategy(n=82)or daily-dosage strategy(n=81).The weekly-dosage group was adjusted the daily dose of warfarin according to the total weekly dose(different daily dose),The warfarin was prescribed at a fixed daily dose or a fixed weekly dose according to INR fluctuation for daily-dosage and weekly dosage group,repectively.So the daily dose for weekly-dosage strategy may be different.The primary end points included frequency of subtherapy(INR < 1.5)and supertherapy(INR>4),percentage of time in target range of INR(TTR value),the rate of TTR reaching target,the time of achieving target INR.The secondary end points were thromboembolism andhemorrhage events during follow-up.Results:There was no significant difference in the baseline data between the two groups;there was no significant difference in the average follow-up time(84.3 weeks vs 85.1weeks p>0.05),average follow-up frequency(16.1 vs.17.0 p>0.05)and warfarin dose(2.5 mg/d vs.2.7 mg/d p>0.05)between the weekly dose group and the daily dose group.In the weekly dose group,the TTR was significantly higher than that in the daily dose group(55.6% vs.45.0%,P < 0.01),the TTR compliance rate was higher than that in the daily dose group(45.1% vs.27.2% P < 0.05),the median time of INR reaching stability(reaching the target at least twice in three consecutive measurements)was significantly lower than that in the daily dose group(7 weeks vs.13 weeks,P <0.01),and the INR percentage of time at a subtherapeutic level was lower than that in the daily dose group(18.3% vs.23.1%,P < 0.01).There was no significant difference in the INR percentage of time at a supertherapeutic level(2.0% vs.3.0% p > 0.05)between the two groups.There was 1 case of cerebral infarction and 2 cases of haemorrhage events in the weekly dose group and 8 cases of embolism and 6 cases of haemorrhage in the daily dose group.The incidence of haemorrhage events in the weekly dose group was lower than that in the daily dose group(2.4% vs.7.4% p >0.05).In the weekly dose group,the incidence of embolism events was significantly lower than that in the daily dose group(1.2% vs.9.9%,P < 0.05),and the incidence of compound endpoint events was significantly lower than that in the daily dose group(3.7% vs.17.3%,P < 0.05).Conclusion:For patients with non-valvular atrial fibrillation,the weekly warfarin administration strategy can significantly improve the efficacy of anticoagulation therapy,achieve the target INR rapidly and reduce the incidence of adverse reaction events.