Safety and efficacy of treatment with vitamin K antagonists in patients managed in a network of anticoagulation services or as routine general care

Abstract

This is a retrospective, record-linkage study aimed at comparing the effectiveness and safety of two management models of vitamin K antagonists: a Network model (NAS), in which anticoagulation clinics and general practitioners (GP) share the same management software and database, and an individual General Practitioners model. Main outcomes were thromboembolic events (TE), major bleeding (MB) and all-cause mortality. Crude incidence rate and sub-distribution hazard ratio were calculated. Fine and Grey models were used to calculate SHR in multi-variable analysis. 9,418 patients in the NAS and 5,508 in the Routine General Care (RGC) cohort were included. Patients in the NAS cohort had a lower incidence of TE and mortality in respect to the RGC (sHR 0.76%, 95% CI 0.64-0.90 and 0.82%, 95% CI 0.75-0.89, respectively). More patients in the NAS than in the RGC cohort attained a Time in Therapeutic Range >60% (62.2% vs 35.7%, p<0.001). No statistically significant difference was found in MB incidence. This study shows that the NAS model for vitamin K antagonist oral anticoagulants management significantly improves the TTR and reduces the incidence of TE and mortality, without affecting the MB rate.