Anticoagulation in atrial fibrillation. A large real-world update
Mario Bo, Stefano Fumagalli, Luca Degli Esposti, Valentina Perrone, Melania Dovizio, Daniela Poli, Rossella Marcucci, Paolo Verdecchia, Gianpaolo Reboldi, Gregory Y.H. Lip, Andrea Ungar, Alessandro Boccanelli, Carlo Fumagalli, Niccolò Marchionni
Abstract
INTRODUCTION: In a large nationwide administrative database including ∼35 % of Italian population, we analyzed the impact of oral anticoagulant treatment (OAT) in patients with a hospital diagnosis of non-valvular atrial fibrillation (NVAF). METHODS AND RESULTS: Of 170404 OAT-naïve patients (mean age 78.7 years; 49.4 % women), only 61.1 % were prescribed direct oral anticoagulants, DOACs, or vitamin-K antagonists, VKAs; 14.2 % were given aspirin (ASA), and 24.8 % no anti-thrombotic drugs (No Tx). We compared ischemic stroke (IS), IS and systemic embolism (IS/SE), intracranial hemorrhage (ICH), major bleeding (MB), major gastro-intestinal bleeding, all-cause deaths and the composite outcome, across four propensity-score matched treatment cohorts with >15400 patients each. Over 2.9±1.5 years, the incidence of IS and IS/SE was slightly less with VKAs than with DOACs (1.62 and 1.84 vs 1.81 and 1.99 events.100 person-years; HR=0.85, 95%CI=0.76-0.95 and HR=0.87, 95%CI=0.78-0.97). This difference disappeared in a sensitivity analysis which excluded those patients treated with low-dose of apixaban, edoxaban, or rivaroxaban (41.7% of DOACs cohort). Compared with DOACs, VKAs were associated with greater incidence of ICH (1.09 vs 0.81; HR=1.38, 95%CI=1.17-1.62), MB (3.78 vs 3.31; HR=1.14, 95%CI=1.02-1.28), all-cause mortality (9.66 vs 10.10; HR=1.07, 95%CI=1.02-1.11), and composite outcome (13.72 vs 13.32; HR=1.04, 95%CI=1.01-1.08). IS, IS/SE, and mortality were more frequent with ASA or No Tx than with VKAs or DOACs (p<0.001 for all comparisons). CONCLUSIONS: Beyond confirming the association with a better net clinical benefit of DOACs over VKAs, our findings substantiate the large proportion of NVAF patients still inappropriately anticoagulated, thereby reinforcing the need for educational programs.