RESUMEN
BACKGROUND: Guidelines on atrial fibrillation (AF) recommend the CHA2DS2-VASc rule for anticoagulant decision-making, but underuse exists. We studied the impact of an automated decision support on stroke prevention in patients with AF in a cluster randomised trial in general practice. METHODS: Intervention practices were provided with a CHA2DS2-VASc based anticoagulant treatment recommendation. Reference practices provided care as usual. The primary outcome was incidence of ischaemic stroke, transient ischaemic attack (TIA) and/or thromboembolism (TE). Secondary outcomes were bleeding and the proportion of patients on guideline recommended anticoagulant treatment. RESULTS: In total, 1129 AF patients were included in the 19 intervention practices and 1226 AF patients in the 19 reference practices. The median age was 77 (interquartile range (IQR) 68-75) years, the median CHA2DS2-VASc score was 3.0 (IQR 2.0-5.0). Underuse of anticoagulants in patients with CHA2DS2-VASc scoreâ¯≥â¯2 was 6.6%. After a median follow-up of 2.7â¯years (IQR 2.3-3.0), the incidence rate per 100 person-years of ischaemic stroke/TIA/TE was 1.96 in the intervention group and 1.42 in the reference group (hazard ratio (HR) 1.3, 95% C.I. 0.8-2.1). No difference was observed in the rate of bleeding (0.79 versus 0.82), or in the underuse (7.2% versus 8.2%) or overuse (8.0% versus 7.9%) of anticoagulation. CONCLUSIONS: In this study in patients with AF in general practice, underuse of anticoagulants was relatively low. Providing practitioners with CHA2DS2-VASc based decision support did not result in a reduction in stroke incidence, affect bleeding risk or anticoagulant over- or underuse.