Current status and value of testing antiphospholipid antibody in patients with acute ischemic stroke: a retrospective single-center study in China

Background and purpose Testing for antiphospholipid antibodies (aPL) is useful to determine the cause of ischemic stroke in young and female patients. However, the clinical relevance of aPL in older patients with ischemic stroke remains unclear. We aimed to explore the status and diagnostic value of initial aPL testing in all patients with acute ischemic stroke.Methods We retrospectively analyzed patients with acute ischemic stroke who were consecutively hospitalized in our hospital between June 2012 and January 2022 and investigated the factors associated with performing aPL screening in real-world clinical practice. Furthermore, factors associated with initial aPL positivity were evaluated by comparing the demographic, etiological, and therapeutic characteristics.Results Of 1209 patients, 287 (23.7%) were tested for aPL and 58 (20.2%) tested positive. Physicians tended to conduct aPL testing on female patients (P<0.001), younger patients (P<0.001), patients with fewer vascular risk factors (P<0.001), and multiple infarctions in the multivascular blood supply area (P<0.001). Multivariate logistic regression analysis showed that only stroke of other determined etiology type was a significant influencing factor for positive aPL results (OR 2.97, 95% CI 1.137, 7.774, P=0.026), adjusting for sex, age, and causes of stroke, etc.Conclusion Approximately one-quarter of the patients with acute ischemic stroke were tested for aPL. Age, sex, number of vascular risk factors, and neuroimaging features affected the discretion in performing aPL testing. aPL testing may be appropriate in older patients with no identified cause of ischemic stroke and may provide additional diagnostic opportunities for acute ischemic stroke.