RESUMEN
BACKGROUND: The Xarelto for Prevention of Stroke in Patients with Atrial Fibrillation (XANTUS) registry investigated the safety and efficacy of the factor Xa inhibitor rivaroxaban. We studied the Dutch XANTUS cohort to a ssess drug safety and prescription patterns in the Netherlands. METHODS: The XANTUS registry was designed as a European prospective, observational study among patients with non-valvular atrial fibrillation. Major bleeding and all-cause mortality were assessed every three months during a 1-year follow-up period. In this Dutch sub-cohort we were also specifically interested in dosing regimens and the incidence and reasons for temporary or permanent discontinuation. RESULTS: Patients (n = 899) had a mean age of 69 (SD ± 9) years and 64.8% were male. The median CHA2DS2-VASc score was 2 (IQR 2-4) and the median HAS-BLED score was 2 (IQR 1-2). Major bleeding occurred in 19 patients (2.4 per 100 patient-years) and 8 patients (1.0 per 100 patient-years) died during the 1year follow-up period. According to renal function, label-discordant dosing was observed in 48 (8.3%) patients. Finally, 124 patients (13.8%) reported a temporary interruption of rivaroxaban treatment and 11.8% switched to another oral anticoagulant therapy after permanent discontinuation of rivaroxaban. CONCLUSION: In the Dutch subset of the XANTUS registry, we observed low rates of major bleeding and label-discordant dosing and high persistence rates during one year of follow-up in patients receiving rivaroxaban in routine clinical practice. However, documenting the motivation of novel oral anticoagulant (NOAC) type and dose is essential to study label-discordant prescription, a potential safety paradox and identify patient characteristics to optimise NOAC use and adherence.