In Turkish patients with atrial fibrillation, warfarin time in therapeutic range <40% was associated with significantly higher rates of death (5.9% vs 3.5%) compared to TTR ≥40%.
Observational (n=572)
Yes
Does a higher time in therapeutic range (TTR ≥ 40%) improve clinical outcomes in patients with atrial fibrillation treated with warfarin?
In a Turkish registry of atrial fibrillation patients, the quality of warfarin anticoagulation was poor (median TTR 40%), and lower TTR was significantly associated with increased mortality, minor bleeding, and cardiac hospitalizations.
Absolute Event Rate: 3.5% vs 5.9%
p-value: p=0.0003
BACKGROUND: Warfarin is highly efficacious in reducing stroke risk in patients with atrial fibrillation (AF). However, its safety and efficacy in stroke prevention is markedly influenced by its time in therapeutic range (TTR). The quality of anticoagulant therapy varies considerably among countries. Representative data concerning the quality of anticoagulant therapy and its effects on clinical outcomes in Turkey are lacking. METHODS: Warfarin in Therapeutic Range (WATER) registry is a prospective, observational study which followed 572 AF patients (mean age 67.3 ± 12 years; females 60%; 71% non-valvular AF) treated with warfarin. RESULTS: At a median of 22-month follow-up, the mean TTR value was 42.3 ± 18% (median: 40%) for the whole population and lower in non-valvular AF su group than valvular AF subgroup (40.3 ± 18 vs. 46.9 ± 19, respectively, p 40% (3.4% vs. 5.9%; 28.6% vs. 35.4%; 36.5% vs. 41.7%, respectively, all of them p < 0.001). A correlation analysis showed a negative correlation between age and TTR value (r = -0.178, p < 0.001). Mean CHA2DS2VASc score was 3.63 ± 1.5 and mean HASBLED score was 2.38 ± 1.01 in the non-valvular AF group. A negative correlation was observed between TTR levels and CHA2DS2VASc score. CONCLUSIONS: WATER provides insight into the anticoagulation control status of AF patients in Turkey. The quality of anticoagulation was poor. Strategies should be undertaken by clinicians and patients to improve TTR. New oral anticoagulant agents may be perfect alternatives for non-valvular AF patients.
Türk et al. (2015) conducted an observational in Atrial fibrillation (n=572). Warfarin time in therapeutic range (TTR) ≥ 40% vs. TTR < 40% was evaluated on Death (p=0.0003). In Turkish patients with atrial fibrillation, warfarin time in therapeutic range <40% was associated with significantly higher rates of death (5.9% vs 3.5%) compared to TTR ≥40%.