Improvement of Oral Anticoagulant Prescription and Long-Term Clinical Outcomes of Patients With Atrial Fibrillation After Implementation of a Clinical Decision Support System in Outpatient Practice.

BACKGROUND: Improving adherence to oral anticoagulants (OACs) is vital for patients with atrial fibrillation. While clinical decision support systems (CDSSs) have shown benefits among hospitalized patients with atrial fibrillation, their real-world effect in outpatient care remains unclear.

METHODS: This single-center, observational study evaluated the impact of an atrial fibrillation CDSS implemented in outpatient clinics since 2017. The system generated alerts recommending anticoagulation based on CHA₂DS₂-VASc and HAS-BLED scores. We compared OAC prescribing patterns, stroke incidence, and major bleeding events before (n=3344) and after (n=3859) CDSS implementation, involving 7203 patients with atrial fibrillation over a 5-year period.

RESULTS: OAC prescription rates increased from 47.3% to 67.5% after CDSS implementation. Direct OAC use rose from 34.6% to 64.4%, while warfarin use declined from 14.1% to 6.4%. Stroke incidence showed a nonsignificant decline (adjusted hazard ratio [HR], 1.28 [95% CI, 0.67-2.46]; P=0.457). Major bleeding events significantly decreased (adjusted HR, 2.07 [95% CI, 1.60-2.68]; P<0.001).

CONCLUSIONS: Outpatient implementation of an atrial fibrillation CDSS was associated with increased OAC use and reduced major bleeding events, potentially due to the replacement of warfarin with a direct OAC. Although the adoption of direct OACs was already increasing, the implementation of the CDSS supported more guideline-adherent anticoagulation prescribing, particularly in high-volume outpatient settings. Further studies are warranted to assess its long-term effect on patient outcomes.