Abstract and Introduction
Abstract
Background: Falls are always a concern regarding the balance of risk/benefit in patients with atrial fibrillation treated with anticoagulants. In this analysis, we aimed to evaluate the outcomes of patients that had a fall/head injury reported in the RE-LY clinical trial (Randomized Evaluation of Long-Term Anticoagulation Therapy) and to explore the safety of dabigatran (a nonvitamin K antagonist oral anticoagulant).
Methods: We performed a post hoc retrospective analysis of intracranial hemorrhage and major bleeding outcomes in the RE-LY trial with 18 113 individuals with atrial fibrillation, according to the status occurrence of falls (or head injury) reported as adverse events. Multivariate Cox regression models were used to provide adjusted hazard ratio (HR) and 95% CI.
Results: In the study, 974 falls or head injury events were reported among 716 patients (4%). These patients were older and had more frequently comorbidities such as diabetes, previous stroke, or coronary artery disease. Patients with fall had a higher risk of major bleeding (HR, 2.41 [95% CI, 1.90–3.05]), intracranial hemorrhage (HR, 1.69 [95% CI, 1.35–2.13]), and mortality (HR, 3.91 [95% CI, 2.51–6.10]) compared to those who did not have reported falls or head injury. Among patients who had falls, those allocated to dabigatran showed a lower intracranial hemorrhage risk (HR, 0.42 [95% CI, 0.18–0.98]) compared with warfarin.
Conclusions: In this population, the risk of falls is important and confers a worse prognosis, increasing intracranial hemorrhage, and major bleeding. Patients who fell and were under dabigatran was associated with lower intracranial hemorrhage risk than those anticoagulated with warfarin, but the analysis was merely exploratory.
Introduction
Atrial fibrillation is the most prevalent persistent arrhythmia, and it is estimated to be present in about 33 million individuals worldwide.[1] Thrombus or thrombi formation due to incompetent atrial contraction may result in embolism to cerebral arteries leading to stroke, which is the main consequence of atrial fibrillation.[2,3] Anticoagulants are therefore essential to prevent thrombus formation and embolic stroke in patients with atrial fibrillation.[4,5]
These drugs increase the risk of bleeding, and such risk is used as an argument against its introduction in more frail patients.[6] To overcome these hypothetical barriers, some studies using vitamin K antagonists claimed that it would be needed 295 falls to have 1 episode of intracranial hemorrhage (ICH).[7] The direct oral anticoagulants or nonvitamin K antagonists oral anticoagulants showed at least noninferiority regarding the risk of stroke or systemic embolism compared with vitamin K antagonists.[8] The lack of important interactions with other drugs or food and the fact that it is needless to monitor international normalized ratio as opposed to vitamin K antagonists, warranting for non-vitamin K antagonists oral anticoagulants some practical advantages and improved patients' satisfaction.[9] The non-vitamin K antagonists oral anticoagulants also showed an improved safety profile, especially regarding the risk of major bleeding and ICH.[10,11]
In this study, we aimed to evaluate the frequency of falls among patients with atrial fibrillation enrolled in The RE-LY trial (Randomized Evaluation of Long-Term Anticoagulation Therapy). We also intended to assess the outcomes of patients with atrial fibrillation that had a fall or head injury, and to explore whether dabigatran treatment interacts with the outcomes in this specific population.
Stroke. 2023;54(6):1656-1659. © 2023 American Heart Association, Inc.
