A Decade of Transformation in Stroke Care in South Korea (2013-2023): Increasing Ambulance Use but Persistent Prehospital Delay and Reversing Mortality Trends.

Background and Purpose: While stroke management has evolved rapidly, comprehensive nationwide evidence covering all stroke subtypes remains limited. We evaluated 10-year secular trends in acute stroke care and outcomes in South Korea using a mandatory national quality audit dataset. Methods: Data from the Acute Stroke Quality Assessment Program, covering nearly all general and tertiary hospitals in Korea, were linked with national insurance claims and mortality records. We analyzed 136,191 episodes of ischemic stroke (IS), intracerebral hemorrhage (ICH), and subarachnoid hemorrhage (SAH) from 2013 to 2023. Results: Over the decade, mean patient age increased (67.1 to 69.6 years), with the ≥85-year population doubling (7.2% to 13.4%). An unexplained discrepancy between ambulance use and arrival time emerged: ambulance use rose (55.4% to 61.8%), but median onset-to-arrival time remained stagnant (4.0 hours), with only 36.6% of IS patients arriving within 3 hours. While intravenous thrombolysis utilization remained stable at approximately 6.0% after 2014, endovascular thrombectomy rates more than doubled (5.3% to 11.6%), reaching 41.1% in severe cases. Statin (92.1%), non-vitamin K antagonist oral anticoagulant (78.4%), and dual antiplatelet therapy (67.2%) use increased markedly. In SAH, treatment shifted from clipping (36.7% to 12.2%) to coiling (36.0% to 63.4%). Notably, adjusted mortality exhibited a non-linear U-shaped trend, reaching a nadir in 2018 followed by an uptick after 2020. Conclusions: Despite substantial improvements in inpatient stroke care, the discrepancy between ambulance use and arrival time highlights structural challenges. Furthermore, the U-shaped mortality reversal underscores the vulnerability of healthcare resilience in a super-aging society, particularly under the strain of the COVID-19 pandemic.