The Effectiveness of Atrial Fibrillation Special Clinic on Oral Anticoagulants Use for High Risk Atrial Fibrillation Patient Managed in the Community

Abstract

Background: There are service gaps existed in atrial fibrillation (AF) management in Hong Kong with relatively low utilization of oral anticoagulants. The purpose of this study was to explore the clinical effectiveness of Atrial Fibrillation Special Clinic (AFSC) by evaluating its impact on the oral anticoagulants use and the control of modifiable cardiovascular disease (CVD) risk factors in high risk AF patients.Method: This was a quasi-experimental, pre-test/post-test study in public primary care clinics. Participants included high risk AF patients with CHA2DS2-VASc score ≥2, had been followed up (FU) for one year at 5 AFSCs of Kowloon Central Cluster (KCC) of the Hospital Authority of Hong Kong from 01 August, 2019 to 31 October, 2020. Our primary outcomes were 1) total number of patients agreed for novel oral anticoagulant (NOAC) treatment after recruitment at AFSC, and 2) modifiable CVD risk factors control including blood pressure (BP), Haemoglobin A1c (HbA1c) if diabetic and low-density lipoprotein-c (LDL-c) level, compared at baseline and after one year FU. Our secondary outcomes were drug-related adverse events, major bleeding and non-major bleeding episodes, stroke or systemic embolism events, Accident and Emergency Department attendance or hospitalisation episodes, survival and mortality rates after one year FU.Results: Among the 299 high risk AF patients included in the study, significant increase in NOAC utilization was observed from 58.5% to 82.6% after FU in AFSC (P <0.001). Concerning the CVD risk factors control, the average diastolic BP level was significantly reduced (P=0.009) and the satisfactory BP control rate in non-DM patients was significantly improved after one year FU (P=0.049). However, the average HbA1c and LDL-c level remained static. The annual incidence rate of ischaemic stroke/systemic embolism was 0.4%, intra-cranial haemorrhage was 0.4%, major bleeding episode was 3.2% and all-cause mortality was 4.3%, all of which were comparable to the literatures. Conclusion: AFSC is effective in enhancing NOAC use and maintaining optimal modifiable CVD risk factors control among high risk AF patients managed in primary care setting, therefore may reduce AF-associated morbidity and mortality in the long run.