Comparison of quality and hemorragic risk of oral anticoagulant therapy using acenocoumarol versus warfarin

BACKGROUND AND OBJECTIVE: Long half life oral anticoagulants have shown a higher anticoagulation stability and a lower hemorragic risk than those of a short half life. We have compared therapeutic stability and hemorragic risk of acenocoumarol versus warfarin in 2 groups of patients on preventive anticoagulation because of atrial fibrilation (international normalised ratio [INR]: 2-3). PATIENTS AND METHOD: Data on 120 patients treated with acenocoumarol and 120 on warfarin treatment who had started and continued treatment in our hospital for a minimum of a year was collected. RESULTS: The percentage of visits within the intended range of INR (2 to 3) was 65.5% with warfarin and 63.4% with acenocoumarol. Thirty percent of patients on warfarin had 75% or more of their controls within range, while for those treated with acenocoumarol this percentage was 22.5%. In the acenocoumarol group, 0.3 visits/patient/year presented an INR >= 6 versus 0.07 in the warfarin group (p = 0.003). CONCLUSIONS: Patients treated with acenocoumarol show a higher risk of presenting with an INR >= 6, but no statistically significant differences are observed in therapeutic stability.