Apixaban versus warfarin in patients with atrial fibrillation according to prior warfarin use: results from the Apixaban for Reduction in Stroke and Other Thromboembolic Events in Atrial Fibrillation trial.
Am Heart J
; 166(3): 549-58, 2013 Sep.
Article
in En
| MEDLINE
| ID: mdl-24016506
ABSTRACT
BACKGROUND:
Patients with atrial fibrillation who are vitamin K antagonist (VKA)-naive may have a higher risk of thrombosis and/or bleeding than VKA-experienced patients. METHODS ANDRESULTS:
Using data from ARISTOTLE, we assessed baseline characteristics and the treatment effect of apixaban versus warfarin in the VKA-naive and VKA-experienced cohorts. We compared rates of study drug discontinuation and time-in-therapeutic range. Overall, 7,800 (43%) were VKA naive, and 10,401 were VKA experienced. At baseline, both groups were similar with respect to age and congestive heart failure, hypertension, age, diabetes, stroke score (CHADS2). Fewer VKA-naive patients had a history of prior stroke (18% vs 21%) or prior bleeding (10% vs 22%) and were more often female (39% vs 33%). The effect of apixaban on the primary efficacy and safety outcomes was similar in VKA-naive (stroke/systemic embolism hazard ratio [HR] 0.86, 95% CI 0.67-1.11 and major bleeding HR 0.73, 95% CI 0.59-0.91) and VKA-experienced populations (stroke/systemic embolism HR 0.73, 95% CI 0.57-0.95, P value for interaction = 0.39 and major bleeding HR 0.66, 95% CI 0.55-0.80, P value for interaction = 0.50). Permanent study drug discontinuation was numerically less likely in patients receiving apixaban whether they were VKA naive (HR for discontinuation 0.87, 95% CI 0.79-0.95) or VKA experienced (HR for discontinuation 0.93, 95% CI 0.85-1.02). Among patients receiving warfarin, the mean/median times in therapeutic range were lower in the VKA-naive group (VKA-naive 57.5/61.4, VKA-experienced 66.0/69.1, P < .001).CONCLUSION:
The treatment effects of apixaban (vs warfarin) were not modified by VKA naivety. The rates of stroke/systemic embolism and major bleeding were numerically lower among the patients assigned to apixaban, irrespective of prior VKA use.
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Main subject:
Pyrazoles
/
Pyridones
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Atrial Fibrillation
/
Thromboembolism
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Warfarin
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Stroke
/
Fibrinolytic Agents
/
Hemorrhage
/
Anticoagulants
Type of study:
Clinical_trials
Limits:
Aged
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Female
/
Humans
/
Male
/
Middle aged
Language:
En
Journal:
Am Heart J
Year:
2013
Type:
Article