Association between intracranial arterial stenosis severity and recurrent stroke risk in elderly ischemic stroke patients

Background and aim Intracranial arterial stenosis (ICAS) is a major cause of ischemic stroke in older adults and is associated with substantial risk of recurrent cerebrovascular events. Whether increasing ICAS severity confers incremental recurrence risk in medically treated elderly patients in routine clinical practice remains incompletely characterized. This study aimed to investigate the association between intracranial arterial stenosis severity and 12-month recurrent stroke risk in elderly patients with ischemic stroke. Methods This single-center retrospective cohort study screened 614 consecutive patients aged 65 years or older who were admitted with acute ischemic stroke between January 2022 and December 2023. After predefined exclusions, 527 patients were included in the final analysis. Intracranial arterial stenosis was assessed using computed tomography angiography or magnetic resonance angiography and categorized as none-to-mild (<50%; including no stenosis), moderate (50–69%), or severe (≥70%) according to the highest-grade lesion. The primary outcome was recurrent ischemic stroke within 12 months. Univariable and multivariable logistic regression models were used to evaluate independent predictors of recurrence. Results Among the 527 included patients, recurrent ischemic stroke occurred in 86 (16.3%) during 12-month follow-up. Recurrence rates increased stepwise across stenosis categories, occurring in 18/214 (8.4%) patients with none-to-mild stenosis, 29/173 (16.8%) with moderate stenosis, and 39/140 (27.9%) with severe stenosis ( p < 0.001). After adjustment for age, sex, vascular risk factors, stroke subtype, baseline NIHSS score, and medication use, severe ICAS remained independently associated with recurrent stroke (adjusted OR 3.12, 95% CI 1.85–5.26, p < 0.001); moderate stenosis was also independently associated with recurrence (adjusted OR 1.96, 95% CI 1.04–3.69, p = 0.037). Conclusion In elderly patients with ischemic stroke, greater intracranial arterial stenosis severity is independently associated with higher 12-month recurrence risk despite contemporary medical management. These findings support early vascular imaging and risk stratification in elderly patients with ischemic stroke.