Association Between Age And Endovascular Treatment Outcomes: Binational Registry Of 9941 EVT Cases From Korea And Taiwan

Background and PurposeAs populations age, there is an increasing need to optimize endovascular treatment (EVT) for acute ischemic stroke. We harmonized prospective stroke registries from Korea and Taiwan to enable direct comparisons of patient characteristics and clinical outcomes, with a particular focus on the impact of advanced age. MethodsProspective stroke registries in South Korea (CRCS-K) and Taiwan (TREAT-AIS) were harmonized to form a unified dataset of patients treated with EVT. EVT outcomes included 3-month modified Rankin Scale (mRS), symptomatic intracranial hemorrhage (SICH), and successful recanalization. We assessed the association between age and outcomes in the overall population and in those aged [≥]80 years, adjusting for relevant covariates. ResultsA total of 9941 EVT cases (7835 from Korea and 2106 from Taiwan) were included. Patients had a mean age of 70.1 {+/-} 12.9 years (57.6% male, median NIHSS: 14 [IQR: 9-19]). Compared to Korean patients, Taiwanese patients had a higher prevalence of vascular risk factors and more severe strokes, contributing to lower rates of favorable 3-month outcomes. Increasing age was associated with poorer EVT results; among patients [≥]80 years, only 18% achieved mRS 0-2, compared to 47% of younger patients. However, the risk of SICH did not significantly increase with age (adjusted OR per year: 1.00 [0.99-1.01]; adjusted OR [≥]80 years: 1.05 [0.85-1.29]). Pre-stroke functional independence and bridging thrombolysis were identified as key modifiers of better outcomes even in the oldest patients. ConclusionTaiwanese EVT patients had more risk factors and worse outcomes than Korean patients. Advanced age is associated with poorer functional recovery, yet selected older patients--particularly those who were functionally independent before the stroke or received bridging thrombolysis--demonstrated meaningful benefit. These results underscore the importance of individualized treatment strategies and careful patient selection, especially as populations continue to age.