(A-138) Anticoagulation Therapy for Non-valvular Atrial Fibrillation in China, 2010-2022

Background: Clinical guidelines recommend consistent oral anticoagulant (OAC) use for stroke prevention in patients with non-valvular atrial fibrillation (NVAF) who are at high risk of stroke. However, the OAC treatment patterns for NVAF in China remain poorly understood.

Objectives: To examine guideline-adherence rate of OAC treatments and its impact on outcomes and the persistence rate for NVAF patients in China.

Methods: We included adults ≥18 years with newly diagnosed NVAF at high stroke risk (CHA2DS2-VASc ≥1 for males, ≥2 for females) from the Yinzhou Health Information System, covering 1.2 million residents in Yinzhou, China, from 2010 to April 2022. Patients with valvular heart disease, prior OAC prescriptions, or conditions requiring OAC use (e.g., deep vein thrombosis, pulmonary embolism, hip/knee replacement) within 365 days before first NVAF diagnosis were excluded. OACs available in healthcare facilities in Yinzhou included NOACs (rivaroxaban, apixaban, dabigatran) and warfarin. Guideline-adherent OAC treatment was defined as initiating OAC therapy for high-risk patients within 90 days after their first NVAF diagnosis. Persistence was assessed over a one-year follow-up and defined as continuous OAC use without gaps exceeding 90 days. Primary outcomes were the proportion of patients receiving guideline-adherent OAC treatment and 360-day persistence. The secondary outcome was the association between OAC initiation and the composite outcome of of ischaemic stroke, thromboembolism, all-cause death. Logistic regression assessed OAC treatment impact, adjusted for CHA2DS2-VASc and HAS-BLED scores, while Kaplan-Meier and log-rank tests measured persistence.

Results: Among 14,710 newly diagnosed NVAF patients identified as high stroke risk between 2010 and April 2022, 3,633 (24.7%) received guideline-adherent OAC treatment. The rate increased from 1.91% in 2010 to 28.84% in 2022, mainly driven by rivaroxaban use. The OAC treatment persistence rates were low, with only 30% of the patients remained on treatment at 60 days and 3.4% at 360 days. Among patients who did not receive OAC treatment, 44.1% were prescribed antiplatelet therapy. Compared to no treatment, guideline-adherent OAC treatment were associated with lower risk of the composite clinical outcome (OR=0.29, 95%CI=0.19-0.44, P< 0.001), whereas antiplatelet therapy alone was associated with a higher risk (OR=1.37, 95%CI=1.00-1.85, P=0.043).

Conclusions: Guideline-adherent initiation and persistence of OAC treatment among NVAF patients in China were inadequate, which were associated with higher mortality. These findings underscore the urgent need for interventions to enhance OAC use and adherence among clinicians and patients.