CHADS2 risk score and rate of stroke or systemic embolism and major bleeding in patients with non-valvular atrial fibrillation receiving non-vitamin K antagonist oral anticoagulants.

Randomized trials showed non-inferior or superior results of the non-vitamin K antagonist oral anticoagulants (NOACs) compared with warfarin in patients with non-valvular atrial fibrillation (AF). Despite the absence of direct head-to-head comparisons between the different NOACs, certain molecules have been proposed for subgroups of patients based mainly on the perception of different bleeding risks. The CHADS2 score has been uniformly used in the inclusion criteria of these studies and shared similar risk factors as the haemorrhagic risk score HAS-BLED. The aim of the present report was to highlight the relationships between CHADS2 score and the rate of stroke or systemic embolism, and the rate of major bleeding in patients with AF on treatment with NOACs. Overall, in all the available randomized studies, a fairly good continuous relationship was observed between the CHADS2 risk score and the rate of stroke or systemic embolism, and the rate of major bleeding in the different studies. Larger registries are needed to confirm this hypothesis.