Factors associated with poor anticoagulation control with vitamin K antagonists among outpatients attended in Internal Medicine and Neurology. The ALADIN study

Abstract

ObjectiveTo identify factors associated with poor anticoagulation control with vitamin K antagonists (VKA) among outpatients with nonvalvular atrial fibrillation (NVAF) attended in Neurology and Internal Medicine in Spain. MethodsCross-sectional and multicenter study, from the ALADIN database, of outpatients with NVAF treated with VKA and attended in Internal Medicine and Neurology in Spain. Rates of anticoagulation control were determined with the direct and Rosendaal methods, considering data from the 6months before the inclusion. ResultsOut of 1337 patients included in the ALADIN study, 750 were taking VKA, and complete information about INR values in the last 6months was available in 383 patients. Mean scores of Charlson Index, CHADS2, CHA2DS2-VASc and HAS-BLED were 1.94±1.54; 3.10±1.26; 4.63±1.54, and 2.20±0.90, respectively. 46.2% and 47.0% of patients had an adequate anticoagulation control according to the direct and Rosendaal methods, respectively. Inadequate anticoagulation control according to the direct method was associated with diabetes (OR: 2.511; 95% CI: 1.144–5.659), prior labile INR (OR: 35.371; 95% CI: 15.058–83.083) and the determination of >6 INR controls in the last 6months (OR: 4.747; 95% CI: 2.094–10.759), and according to the Rosendaal method, with prior labile INR (p<.001) and HAS-BLED score (OR: 3.991; 95% CI: 2.520–6.319). ConclusionsDespite the high thromboembolic risk, only a little more than a half of patients were well controlled. Factors associated with poor anticoagulation control were diabetes, labile INR, >6 INR controls and HAS-BLED.