BackgroundThis study described the clinical and demographic characteristics of hospitalized patients with nonvalvular atrial fibrillation (NVAF) and prescriptions for vitamin-K antagonists (VKA) and direct-acting oral anticoagulants (DOAC) in Spain.MethodsThis was an observational, multicentric, retrospective study of patients treated with DOAC or VKA due to NVAF at cardiology services of hospitals in Spain. A registry (CARISMA) included patients hospitalized for any reason and discharged before July 1st, 2021, with a prescription for DOAC or VKA. Data was collected on demographic and clinical characteristics and anticoagulant treatments prescribed. Analyses were descriptive.ResultsA total of 1,041 patients were included. Mean age (SD) was 77.2 (10.3) years and 57.6 % were men. The most frequent reason for hospital admission was heart failure (43.8 %) and arrhythmias (25.0 %). The mean (SD) CHA2DS2-VASc score was 4.0 (1.6). Prior to admission, 75.6 % of patients had been prescribed anticoagulant treatment for NVAF. Of these, 56.0 % had received VKA and 44.0 % DOAC. At discharge, 60 % had a DOAC prescription (of these, apixaban, 37.6 %; edoxaban, 26.4 %; rivaroxaban, 25.1 %; dabigatran, 10.9 %) and 40 % a VKA. DOAC prescriptions were off-label with respect to dosing in 19-34 % of cases. Patients with off-label dosing were older and with a higher proportion of women than those with on-label doses. During hospitalization, 12.1 % of patients changed treatment, usually VKA to DOAC.ConclusionBefore hospitalization, a quarter of patients with NVAF were not receiving anticoagulation medication. Hospitalization increased the proportion of patients receiving DOAC, but about a quarter of patients had off-label dosing prescriptions.