In patients with device-detected atrial fibrillation and a high comorbidity burden, oral anticoagulation increases bleeding without a clear reduction in stroke. This is the main finding of a sub-analysis of the NOAH – AFNET 6 trial presented by Dr Julius Nikorowitsch, University Medical Center Hamburg-Eppendorf (UKE), Hamburg, Germany, in a late-breaking science session at the annual congress of the European Heart Rhythm Association (EHRA) in Berlin, Germany, today and simultaneously published in the European Heart Journal (1).