Serial changes in the trends of direct oral anticoagulant use and incidence of thromboembolisms and major bleeding events in very old patients with non-valvular atrial fibrillation.

Aims: Direct oral anticoagulants (DOACs) have become the first-line antithrombotic therapy in patients with non-valvular atrial fibrillation (NVAF). During this period, the incidence of thromboembolisms and major bleeding events has decreased. However, no studies have shown a correlation between them, and even fewer data are available on older patients. Therefore, we evaluated the serial changes in oral anticoagulant (OAC) use and the correlation between DOAC use and the incidence of adverse events among very old patients with NVAF. Methods and results: We conducted a historical cohort study in 1320 consecutive patients with NVAF aged ≥80 years who received medical treatment for AF from March 2011 to February 2021. We analysed the temporal trends regarding patients using OACs, including the DOAC prescription rate and incidence of adverse events. Over the last decade, the number of patients using OACs has increased from 228 to approximately 600 person-years. The DOAC prescription rate has significantly increased (4-90%, Conclusion: The incidence of thromboembolisms and major bleeding events might be inversely correlated with the increase in the DOAC prescription rate in patients with NVAF aged ≥80 years.