Effectiveness and Safety of Edoxaban Compared With Apixaban in Elderly Patients With Nonvalvular Atrial Fibrillation: A Real-World Population-Based Cohort Study.

BACKGROUND: The very elderly (≥80 years) are at high risk of nonvalvular atrial fibrillation and thromboembolism. Given its recent approval, the comparative effectiveness and safety of edoxaban in this population, relative to the commonly used apixaban, remain unknown. METHODS: Using the United Kingdom Clinical Practice Research Datalink, we identified a cohort of patients aged ≥80 with incident nonvalvular atrial fibrillation and newly treated with edoxaban or apixaban between 2015 and 2021. Cohort entry was defined as the first prescription for one of the 2 drugs. We used propensity score fine stratification and weighting for confounding adjustment. A weighted Cox proportional hazards model was used to estimate the hazard ratios (HR) with 95% CI of ischemic stroke/transient ischemic attack/systemic embolism (primary effectiveness outcome) and of major bleeding (primary safety outcome) associated with edoxaban compared with apixaban. We also assessed the risk of all-cause mortality and a composite outcome of ischemic stroke/transient ischemic attack, systemic embolism, gastrointestinal bleeding, and intracranial hemorrhage as secondary outcomes. RESULTS: The cohort included 7251 new-users of edoxaban and 39 991 of apixaban. Edoxaban and apixaban had similar incidence rates of thromboembolism (adjusted rates, 20.38 versus 19.22 per 1000 person-years; adjusted HR, 1.06 [95% CI, 0.89-1.26]), although the rates of major bleeding were higher with edoxaban (adjusted rates, 45.57 versus 31.21 per 1000 person-years; adjusted HR, 1.42 [95% CI, 1.26-1.61]). The risk of the composite outcome was 21% higher with edoxaban (adjusted HR, 1.21 [95% CI, 1.07-1.38]). All-cause mortality was similar between edoxaban and apixaban (adjusted HR, 1.04 [95% CI, 0.96-1.12]). CONCLUSIONS: In very elderly patients with nonvalvular atrial fibrillation, edoxaban resulted in similar thromboembolism prevention as apixaban, although it was associated with a higher risk of major bleeding. These findings may improve the management of nonvalvular atrial fibrillation by informing physicians on the choice of anticoagulant for this vulnerable population.

Concomitant Use of Selective Serotonin Reuptake Inhibitors With Oral Anticoagulants and Risk of Major Bleeding.

Importance: Selective serotonin reuptake inhibitors (SSRIs) are commonly prescribed antidepressants associated with a small increased risk of major bleeding. However, the risk of bleeding associated with the concomitant use of SSRIs and oral anticoagulants (OACs) has not been well characterized. Objectives: To assess whether concomitant use of SSRIs with OACs is associated with an increased risk of major bleeding compared with OAC use alone, describe how the risk varies with duration of use, and identify key clinical characteristics modifying this risk. Design, Setting, and Participants: A population-based, nested case-control study was conducted among patients with atrial fibrillation initiating OACs between January 2, 1998, and March 29, 2021. Patients were from approximately 2000 general practices in the UK contributing to the Clinical Practice Research Datalink. With the use of risk-set sampling, for each case of major bleeding during follow-up, up to 30 controls were selected from risk sets defined by the case and matched on age, sex, cohort entry date, and follow-up duration. Exposures: Concomitant use of SSRIs and OACs (direct OACs and vitamin K antagonists [VKAs]) compared with OAC use alone. Main Outcomes and Measures: The main outcome was incidence rate ratios (IRRs) of hospitalization for bleeding or death due to bleeding. Results: There were 42 190 patients with major bleeding (mean [SD] age, 74.2 [9.3] years; 59.8% men) matched to 1 156 641 controls (mean [SD] age, 74.2 [9.3] years; 59.8% men). Concomitant use of SSRIs and OACs was associated with an increased risk of major bleeding compared with OACs alone (IRR, 1.33; 95% CI, 1.24-1.42). The risk peaked during the initial months of treatment (first 30 days of use: IRR, 1.74; 95% CI, 1.37-2.22) and persisted for up to 6 months. The risk did not vary with age, sex, history of bleeding, chronic kidney disease, and potency of SSRIs. An association was present both with concomitant use of SSRIs and direct OACs compared with direct OAC use alone (IRR, 1.25; 95% CI, 1.12-1.40) and concomitant use of SSRIs and VKAs compared with VKA use alone (IRR, 1.36; 95% CI, 1.25-1.47). Conclusions and Relevance: This study suggests that among patients with atrial fibrillation, concomitant use of SSRIs and OACs was associated with an increased risk of major bleeding compared with OAC use alone, requiring close monitoring and management of risk factors for bleeding, particularly in the first few months of use.