Safety and efficacy of anticoagulation for cerebral amyloid angiopathy patients with high-risk atrial fibrillation

Background: Cerebral amyloid angiopathy (CAA) significantly increases intracranial hemorrhage (ICH) risk and the safety of anticoagulation (AC) among CAA patients with atrial fibrillation (AF) is uncertain. Methods: This was a retrospective cohort study of the TriNetX US collaborative network. Elderly CAA patients (≥ 65 years old) with newly diagnosed high-risk AF (CHA₂DS₂-VASc ≥ 2 for men and ≥ 3 for women) were included; patients with prior ischemic or hemorrhagic stroke were excluded. Patients treated with apixaban or rivaroxaban were compared to no AC treatment. Propensity score matching (PSM) was used to balance groups. Primary outcomes were ischemic stroke and ICH within 3 years assessed with Kaplan–Meier analyses; secondary outcomes included major hemorrhage and patient death. Results: 821 patients were included (462 AC, 359 no AC); after PSM, 287 patients remained in each group. AC was significantly associated with lower stroke risk (event probability 1.0% vs 5.7% at 3 years, p = 0.016) without increasing intracerebral hemorrhage risk (3.0% vs 3.9%, p = 0.21). Major hemorrhage rates were comparable (8.1% vs 10.7%, p = 0.09), and mortality was lower with AC (27.9% vs 33.5%, p = 0.049). Conclusions: Anticoagulation for elderly CAA patients with newly diagnosed high-risk AF and without prior history of ischemic or hemorrhagic stroke was associated with lower risks of ischemic stroke and death without higher risk of hemorrhage.