Impact of atrial fibrillation and intracranial or extracranial cerebral large artery stenosis on the short-term recurrence of acute ischemic stroke: a multicenter retrospective study

With advances in diagnostic technologies, the proportion of strokes identified with multiple causes is increasing, and conventional classifications for ischemic stroke subtypes do not adequately reflect functional outcome or risk of recurrence. The purpose of this multicenter retrospective study was to examine whether a clinically pragmatic classification system based on atrial fibrillation (AF), symptomatic intracranial or extracranial cerebral large artery stenosis or occlusion (sICS), infarct distribution, and multiple infarctions could stratify the short-term risk of recurrence or death. Consecutive ischemic stroke patients admitted to any of three stroke centers within 7 days of onset from January 2017 to May 2022 were registered in the study database. We performed a retrospective complete-case analysis after excluding patients with missing admission National Institutes of Health Stroke Scale (NIHSS) scores or unavailable 3-month follow-up. Patients were divided into 4 groups on the basis of the presence or absence of AF and sICS and into 2 groups on the basis of the distribution of infarctions. The presence of multiple infarctions was also investigated. The frequency and clinical factors of stroke recurrence or death over 3 months were observed. Data from 1905 patients were analyzed. The frequency of stroke recurrence or death from all causes within 3 months was 31.4% in the AF + sICS + group, 16.7% in the AF + sICS- group, 15.7% in the AF- sICS + group, and 11.5% in the AF- sICS- group. Multivariate logistic regression analysis for recurrence or death during 3 months revealed a significantly greater risk in the AF + sICS + group than in the AF + sICS- group (odds ratio, 2.31; 95% confidence interval, 1.37–3.88; p = 0.0017). The coexistence of AF and sICS was associated with short-term recurrence and mortality. Classification using AF, sICS, infarct distribution, and multiple infarctions may help stratify the risk of short-term recurrence or death in patients with acute ischemic stroke. The new classification proposed in this study is expected to be further validated in future prospective studies and to contribute to the establishment of optimal treatment strategies for each subgroup.