Antiphospholipid Syndrome as an Under-Recognized Cause of Ischemic Stroke in Older Adults: A Retrospective Case Series.

Background, objective, and methods: Antiphospholipid syndrome (APS) is classically regarded as a cause of thrombosis and stroke in younger patients and is often considered a rare etiology beyond the sixth decade. We retrospectively describe seven older adults (ages 67-90 years; median 76; four females) with ischemic stroke in whom antiphospholipid antibodies (aPL) were identified during evaluation, most after one or more cerebrovascular events. Results: Six of the seven had radiographic or clinical evidence of prior cerebrovascular disease, and several had experienced recurrent events despite antiplatelet or anticoagulant therapy. Antibody profiles were heterogeneous, ranging from triple positivity with confirmed persistence to isolated lupus anticoagulant and IgM-only positivity, and competing stroke mechanisms (patent foramen ovale, large-artery atherosclerosis, and small-vessel disease) were frequently present. All patients were transitioned to a vitamin K antagonist. Conclusions: This series illustrates that aPL-associated stroke does occur in older adults and supports considering APS in the differential of cryptogenic or recurrent ischemic stroke in this population, while underscoring the need for high-specificity, persistently confirmed testing before committing a patient to lifelong anticoagulation.