Apixaban vs Aspirin According to CHA2DS2-VASc Score in Subclinical Atrial Fibrillation
Renato D. Lópes, Christopher B. Granger, Daniel Wojdyla, William F. McIntyre, Marco Alings, Thenmozhi Mani, Chinthanie Ramasundarahettige, Léna Rivard, Dan Atar, David H. Birnie, Giuseppe Boriani, Guy Amit, Peter Leong‐Sit, Claus Rinne, Gábor Zoltán Duray, Michael R. Gold, Stefan H. Hohnloser, Valentina Kutyifa, Juan Benezet‐Mazuecos, Jens Cosedis Nielsen, Christian Sticherling, Alexander P. Benz, Cecilia Linde, J Kautzner, Philippe Mabo, Georges H. Mairesse, Stuart J. Connolly, Jeff S. Healey
Abstract
ARTESiA (Apixaban for the Reduction of Thrombo-Embolism in Patients With Device-Detected Sub-Clinical Atrial Fibrillation) demonstrated that apixaban, compared with aspirin , significantly reduced stroke and systemic embolism (SE) but increased major bleeding in patients with subclinical atrial fibrillation. To help inform decision making, the authors evaluated the efficacy and safety of apixaban according to baseline CHA 2 DS 2 -VASc score. We performed a subgroup analysis according to baseline CHA 2 DS 2 -VASc score and assessed both the relative and absolute differences in stroke/SE and major bleeding. Baseline CHA 2 DS 2 -VASc scores were <4 in 1,578 (39.4%) patients, 4 in 1,349 (33.6%), and >4 in 1,085 (27.0%). For patients with CHA 2 DS 2 -VASc >4, the rate of stroke was 0.98%/year with apixaban and 2.25%/year with aspirin ; compared with aspirin, apixaban prevented 1.28 (95% CI: 0.43-2.12) strokes/SE per 100 patient-years and caused 0.68 (95% CI: −0.23 to 1.57) major bleeds . For CHA 2 DS 2 -VASc <4, the stroke/SE rate was 0.85%/year with apixaban and 0.97%/year with aspirin. Apixaban prevented 0.12 (95% CI: −0.38 to 0.62) strokes/SE per 100 patient-years and caused 0.33 (95% CI: −0.27 to 0.92) major bleeds . For patients with CHA 2 DS 2 -VASc =4, apixaban prevented 0.32 (95% CI: −0.16 to 0.79) strokes/SE per 100 patient-years and caused 0.28 (95% CI: −0.30 to 0.86) major bleeds. One in 4 patients in ARTESiA with subclinical atrial fibrillation had a CHA 2 DS 2 -VASc score >4 and a stroke/SE risk of 2.2% per year. For these patients, the benefits of treatment with apixaban in preventing stroke/SE are greater than the risks. The opposite is true for patients with CHA 2 DS 2 -VASc score <4. A substantial intermediate group (CHA 2 DS 2 -VASc =4) exists in which patient preferences will inform treatment decisions. (Apixaban for the Reduction of Thrombo-Embolism in Patients With Device-Detected Sub-Clinical Atrial Fibrillation ; NCT01938248 )