Glycemic status and risks of thromboembolism and major bleeding in patients with atrial fibrillation

BACKGROUND: Studies specifically examining the association between glycated hemoglobin A1c (HbA1c) levels and ischemic stroke/systemic thromboembolism (IS/SE) risk in atrial fibrillation (AF) patients are limited. Here, we investigated the association between HbA1c levels and the risk of IS/SE, as well as major bleeding, among AF patients with or without oral anticoagulants (OACs). We also compared the effectiveness and safety of warfarin and direct oral anticoagulants (DOACs) in different HbA1c categories. METHODS: We utilized medical data from a multi-center healthcare provider in Taiwan, which included 34,036 AF patients with serum HbA1c data available within 3 months after AF being diagnosed. Patients were divided into seven study groups according to their HbA1c levels: 0.05). CONCLUSION: For AF patients, IS/SE risk significantly increased once HbA1c levels exceeded 6.5%, and OACs may attenuate these associations. Compared with warfarin, DOACs were more effective and safer across broad HbA1c categories. Therefore, in addition to prescribing DOACs when indicated, more aggressive glycemic control to achieve an HbA1c level < 6.5% may be considered for eligible AF patients and should be tested in further prospective studies.