A New Index to Predict Quality of Anticoagulation Control in Patients On Vitamin K Antagonists: the Dafne Score

<b>Aim:</b> To derive a new clinical score to improve the prediction of those at risk of poor International Normalized Ratio control among patients with atrial fibrillation taking vitamin K antagonists. <b>Materials & methods:</b> The score was calculated using PAULA database and validated in the FANTASIIA population. <b>Results:</b> The DAFNE score (cardiovascular <b>D</b>isease, concomitant treatment with <b>A</b>miodarone, <b>F</b>ood/dietary transgression and taking ≥7 pills daily, f<b>E</b>emale sex) score was related to a higher probability of poor International Normalized Ratio control. C-indexes were 0.611 and 0.576 (De Long test, p = 0.007) for the DAFNE and SAMe-TT₂R₂ scores, respectively. <b>Conclusion:</b> The DAFNE score is a new clinical score which may potentially help determine those patients with atrial fibrillation who are at high risk of poor anticoagulation control with vitamin K antagonists.