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

Article information

J Stroke. 2026;.jos.2026.00360

Publication date (electronic) : 2026 June 30

doi : https://doi.org/10.5853/jos.2026.00360

Jun Yup Kim¹, Seong-Eun Kim¹, Do Yeon Kim¹, Jihoon Kang¹, Beom Joon Kim¹, Yong Soo Kim², Dong-Wan Kang², Han-Gil Jeong², Tae Jung Kim³, Hong-Kyun Park⁴, Yong-Jin Cho⁴, Jong-Moo Park⁵, Kyungbok Lee⁶, Soo Joo Lee⁷, Ji Sung Lee⁸, Juneyoung Lee⁹, Yong Uk Kwon¹⁰, Yu Ra Lee¹¹, Yu Jeong Lim¹², Hee-Joon Bae^,1

¹Department of Neurology, Seoul National University College of Medicine, Seoul National University Bundang Hospital, Seongnam, Korea

²Division of Intensive Care Medicine, Department of Neurosurgery and Neurology, Seoul National University Bundang Hospital, Seongnam, Korea

³Department of Neurology, Seoul National University College of Medicine, Seoul National University Hospital, Seoul, Korea

⁴Department of Neurology, Inje University Ilsan Paik Hospital, Goyang, Korea

⁵Department of Neurology, Uijeongbu Eulji Medical Center, Eulji University, Uijeongbu, Korea

⁶Department of Neurology, Soonchunhyang University Hospital, Soonchunhyang University College of Medicine, Seoul, Korea

⁷Department of Neurology, Eulji University Hospital, Daejeon, Korea

⁸Department of Clinical Epidemiology and Biostatistics, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea

⁹Department of Biostatistics, Korea University College of Medicine, Seoul, Korea

¹⁰Healthcare Review and Assessment Committee, Health Insurance Review and Assessment Service, Wonju, Korea

¹¹Quality Assessment Administration Department, Health Insurance Review and Assessment Service, Wonju, Korea

¹²Quality Assessment Management Department, Health Insurance Review and Assessment Service, Wonju, Korea

Correspondence: Hee-Joon Bae Department of Neurology, Seoul National University College of Medicine, Cerebrovascular Center, Seoul National University Bundang Hospital, 82 Gumi-ro 173 beon-gil, Bundang-gu, Seongnam 13620, Korea Tel: +82-31-787-7467 E-mail: braindoc@snu.ac.kr

Received 2026 January 15; Revised 2026 April 6; Accepted 2026 April 27.

Abstract

Introduction

Acute stroke care has evolved significantly over the past decade, driven by advancements in intravenous thrombolysis (IVT) [1] and endovascular thrombectomy (EVT) [2,3] for ischemic stroke (IS), comprehensive bundle care [4,5] and surgical management [6] for intracerebral hemorrhage (ICH), and coil embolization [7] for ruptured aneurysmal subarachnoid hemorrhage (SAH). While multiple randomized clinical trials have established the efficacy of these interventions, there is a pressing need for detailed analyses of real-world secular trends through nationwide reports to evaluate the actual impact and sustainability of these advancements.

However, existing nationwide studies often face methodological constraints that limit their clinical utility. Registry-based reports frequently rely on voluntary participation, which may lead to selection bias by excluding smaller or lower-performing facilities. Conversely, analyses based solely on administrative data often lack the clinical depth necessary to capture nuanced management metrics beyond mortality or basic hospital volume [8,9]. Furthermore, most existing nationwide studies focus exclusively on IS, providing a fragmented view of the overall stroke care landscape that neglects the distinct management shifts in ICH and SAH [10,11].

South Korea presents a unique clinical landscape due to its exceptionally rapid transition into a super-aging society, which places unprecedented pressure on the national stroke care system [12]. To address the limitations of prior research, this study utilizes the Acute Stroke Quality Assessment Program (ASQAP), a mandatory nationwide audit program evaluating inpatient care for nearly all acute stroke cases treated in general and tertiary hospitals across the country [13]. By integrating these mandatory clinical records with national insurance claims and the gold-standard resident registration system for mortality outcomes, we have established a robust longitudinal database with unparalleled representativeness and clinical granularity.

In this study, we sought to determine whether a decade (2013–2023) of systemic and clinical advancements has translated into sustained improvements in stroke outcomes across the full spectrum of stroke subtypes, including IS, ICH, and SAH. By evaluating the longitudinal evolution of management patterns—from prehospital metrics to advanced pharmacological and surgical interventions—this research aims to identify persistent challenges and assess the resilience of the national stroke care system in an era of rapid demographic change.

Methods

Results

Baseline characteristics

The ASQAP database (n=136,191), reflecting the mandatory nationwide audit of nearly all acute stroke cases in Korea, revealed significant demographic and clinical shifts between 2013 and 2023 (Table 1). The mean age of patients increased significantly from 67.1±13.4 years to 69.6±13.7 years (P_trend<0.001). Notably, the proportion of the “old-old” population (aged ≥85 years) nearly doubled from 7.2% to 13.4%, highlighting a rapid transition toward a super-aging society (P_trend<0.001). While IS consistently comprised approximately 75% of all cases, the proportion of SAH cases decreased significantly from 9.6% to 7.4% (P_trend<0.001). Stroke severity for IS exhibited a shift toward milder deficits, with the proportion of severe cases (NIHSS ≥16) declining from 9.7% to 8.6% (P_trend=0.006).

Table 1.

Baseline characteristics of patients with acute stroke (2013–2023)

Prehospital care

Despite advancements in healthcare infrastructure, prehospital delays remained a persistent challenge (Table 2). The median symptom onset-to-arrival time for any stroke was stagnant at approximately 4.0 hours. Alarmingly, only one out of three IS patients arrived within the critical 3-hour window, a figure that showed no improvement over the decade.

Table 2.

Prehospital triage and care metrics by stroke subtype

However, systemic improvements in prehospital triage were evident across several indicators. Ambulance utilization increased significantly across all subtypes (any stroke: 55.4% to 61.8%, P_trend<0.001). Direct routing to specialized facilities also matured, as evidenced by a significant increase in admissions to stroke centers (55.8% to 78.2%, P_trend<0.001) and a corresponding reduction in inter-hospital referral rates from 10.9% to 5.2% (P_trend<0.001).

In stratified analyses according to ambulance use (Supplementary Table 1), patients transported by ambulance consistently demonstrated substantially shorter onset-to-arrival times than those who did not use ambulance services across all study periods. For example, in 2022/2023, the median arrival time for any stroke was 2.3 hours in the ambulance group compared with 9.8 hours in the non-ambulance group. Similarly, the proportion arriving within 3 hours was consistently higher among ambulance users. Notably, temporal trends differed qualitatively between the two groups (P_interaction<0.001). While the ambulance group showed a modest but significant decrease in median arrival time over the decade (2.5 to 2.3 hours; P_trend=0.003), the non-ambulance group experienced a progressive worsening (7.9 to 9.8 hours; P_trend<0.001). These findings indicate that the population-level stagnation in arrival times primarily reflects the growing prehospital delay among patients not utilizing emergency services.

Hospital management

IVT utilization for IS stabilized at approximately 6.0% after 2014 (Table 3). Regarding the efficiency of hyperacute care, approximately 85% of patients achieved door-to-needle (DTN) times of ≤60 minutes, maintaining a consistent performance level without significant temporal trend. In contrast, EVT utilization more than doubled from 5.3% to 11.6% overall (P_trend<0.001). This surge was most prominent in severe IS (NIHSS ≥16), where EVT rates skyrocketed from 18.3% to 41.1% (P_trend<0.001). Furthermore, late-window thrombectomy (6–24 hours) increased threefold (3.0% to 10.1%). Carotid artery stenting utilization also rose (1.7% to 2.5%, P_trend<0.001), while carotid endarterectomy remained consistently low. Decompressive surgery for severe IS (NIHSS ≥15) was performed in 3.6% to 5.1% of patients, maintaining a stable trend over the study period.

Table 3.

Temporal trends in acute management and revascularization for ischemic stroke

A substantial transition was observed in pharmacological management at discharge (Table 4 and Supplementary Table 2). Statin prescription rates increased steadily from 73.4% to 92.1%. Antithrombotic therapy moved toward intensity, with dual or multiple antiplatelet therapy use rising from 55.4% to 67.2% (P_trend<0.001). The most profound change occurred in atrial fibrillation management. Warfarin use plummeted (53.6% to 6.3%), while non-vitamin K antagonist oral anticoagulant (NOAC) utilization surged from 4.5% to 78.4% (P_trend<0.001). By 2023, apixaban (37.7%) and edoxaban (24.5%) emerged as the most widely adopted agents.

Table 4.

Pharmacological management at discharge for ischemic stroke

Management of hemorrhagic stroke showed a definitive transition toward minimally invasive techniques in SAH, while surgical patterns for ICH remained stable (Table 5). In SAH, surgical clipping plummeted (36.7% to 12.2%, P_trend<0.001), while endovascular coiling became the predominant modality, nearly doubling to 63.4% (P_trend<0.001). Decompressive surgery rates for ICH remained stable between 25.0% and 29.7%. Inpatient rehabilitation utilization and transfers to specialized facilities increased significantly across all subtypes, indicating an enhanced post-acute care continuum (Supplementary Table 3).

Table 5.

Longitudinal shifts in surgical and interventional management of hemorrhagic stroke

Outcomes

Crude mortality rates showed significant improvements especially in SAH, with 1-month mortality declining from 29.0% in 2013 to 23.0% in 2022/2023 (P_trend<0.001) (Figure 1 and Supplementary Table 4). For other subtypes, crude mortality remained relatively stable. After adjusting for age, sex, and stroke severity, no significant long-term linear trends in mortality were observed across any stroke subtype. Results were materially unchanged after additional adjustment for CCI score (Supplementary Table 4).

Figure 1.

Trends in crude mortality rates across stroke subtypes (2013–2023). Longitudinal trends in crude mortality for (A) any stroke, (B) ischemic stroke, (C) ICH, and (D) SAH. A significant decline in 1-month mortality was observed only in SAH (P_trend<0.001). ICH, intracerebral hemorrhage; SAH, subarachnoid hemorrhage.

However, RCS modeling revealed a non-linear U-shaped association between calendar years and mortality outcomes. Significant non-linearity was observed for adjusted mortality in any stroke and IS (all P_{non-linearity}<0.001) (Figure 2 and Supplementary Table 5). The spline curves showed an initial decline in adjusted mortality rates, with a nadir observed around 2018, followed by an increase in later years.

Figure 2.

Restricted cubic spline curves for non-linear trends in 1-year mortality. Predicted 1-year mortality odds ratio using 3-knot restricted cubic splines, adjusted for age, sex, and stroke severity. Shaded areas indicate 95% CIs. Significant U-shaped trends (P_{non-linearity}<0.001) are shown for any stroke and ischemic stroke. ICH, intracerebral hemorrhage; SAH, subarachnoid hemorrhage; CI, confidence interval.

Discussion

This study, utilizing a mandatory nationwide audit program, provides a comprehensive 10-year panorama of acute stroke care and outcomes in South Korea. Over the decade, we observed a substantial change in stroke management, characterized by the rapid adoption of endovascular therapies, a near-complete transition to NOACs, and a definitive shift toward minimally invasive interventions for SAH. However, our analysis also identified critical systemic bottlenecks, particularly a persistent prehospital delay and a concerning U-shaped reversal in adjusted mortality following the COVID-19 pandemic.

The unexplained discrepancy between ambulance use and arrival time remains one of the most critical challenges identified in this study. While ambulance utilization significantly increased across all stroke subtypes and direct routing to specialized stroke centers reached over 78.2%, the proportion of patients arriving within the 3-hour golden window remained disappointingly stagnant. This disconnect suggests that improving prehospital care requires more than just increasing public awareness or physical infrastructure. It highlights potential structural deficiencies within the current Emergency Medical Service (EMS) system, where prehospital triage and initial response protocols may not be sufficiently optimized for rapid stroke identification and dispatch. To bridge this gap, future research and policymaking should prioritize linking ASQAP data with EMS-specific databases. Such data linkage would allow for the granulation of prehospital time into “onset-to-first medical contact (FMC)” and “FMC-to-hospital arrival,” enabling targeted interventions to reduce systemic delays [16].

In the management of IS, the surge in EVT utilization—particularlyIn the management of IS, the surge in EVT utilization—particularly reaching 41.1% in severe cases—represents the most dynamic clinical change. This reflects the prompt integration of landmark trial evidence into real-world practice [17,18]. Interestingly, while the efficiency of hyperacute care remains high with 85% of patients achieving DTN time ≤60 minutes, this figure has plateaued. This “ceiling effect” indicates that most participating hospitals have already reached a high level of performance, yet further reduction in DTN time may require more advanced systemic interventions, such as pre-notification systems [19] or mobile stroke units [20]. The stabilization of IVT rates around 6.0% after 2014, despite the EVT surge, suggests a paradigm shift where clinical decision-making is increasingly tailored toward large vessel occlusion management, potentially prioritized over traditional thrombolysis in eligible cases [21]. In addition to EVT expansion, several other factors may have contributed to the IVT plateau. The 2013 American Heart Association/American Stroke Association guidelines [22] and the contemporaneous Korean Stroke Society guidelines extended IVT eligibility from 3 to 4.5 hours after symptom onset [23], which likely contributed to the initial increase in IVT utilization observed in 2014 (8.4%). However, because patients aged >80 years were excluded from the European Cooperative Acute Stroke Study III trial [24] that informed these guidelines, national reimbursement coverage for IVT in this age group remained restricted, potentially explaining the marked decline in IVT use among patients aged ≥80 years from 6.0% (2014) to 0.7% (2018). Following a revision of the HIRA reimbursement criteria in 2018 that removed this age restriction, IVT rates in patients aged ≥80 years rebounded to 4.8% (2020/2021) and 5.4% (2022/2023). Despite this recovery in the elderly subgroup, the overall national IVT rate remained stable at approximately 6%, reflecting a multifactorial equilibrium between expanding EVT indications, demographic aging, and evolving reimbursement policies.

The pharmacological landscape has been equally transformative, marked by near-universal statin prescriptions, the dominance of NOACs, and an increasing reliance on dual antiplatelet therapy (DAPT). Statin utilization increased to 92.1%, becoming a non-negotiable standard of care [25,26]. NOAC utilization skyrocketed to 68.4%, with apixaban and edoxaban emerging as the preferred agents, a trend that mirrors global shifts toward more patient-friendly and effective anticoagulation [26,27]. Furthermore, the significant rise in DAPT use at discharge (55.4% to 67.2%) demonstrates the rapid real-world implementation of recent evidence supporting its efficacy in minor stroke and transient ischemic attack [28,29]. These trends demonstrate that Korean clinicians are highly responsive to evidence-based guidelines, leading to a high degree of pharmacological optimization across the nation.

A key success story is the management of SAH, which was the only subtype to demonstrate a significant decline in crude mortality. This improvement is inextricably tied to the transition from surgical clipping to endovascular coiling—reaching 63.4%— and the increased focus on prophylactic management of unruptured aneurysms [30]. The declining proportion of SAH among all strokes further supports the success of nationwide screening and preventive coiling programs in reducing the incidence of aneurysmal rupture [31]. In contrast, management for ICH remained largely stable, though the emerging role of minimally invasive hematoma evacuation may disrupt this clinical equilibrium in the near future [32].

The most concerning finding is the non-linear “U-shaped” trend in adjusted mortality, with rates reaching a nadir in 2018 followed by a significant uptick after 2020. This reversal suggests that the progress made in the first half of the decade was offset by the combined impact of an exponentially aging population and the systemic disruptions of the COVID-19 pandemic [33]. Although the temporal increase coincided with the COVID-19 pandemic period, no pandemic-specific or system-level variables could be included in the analysis, precluding causal inference. Other plausible explanations include the rapid growth of the very elderly population and increasing frailty and comorbidity burden. The doubling of the “old-old” (≥85 years) demographic places unprecedented strain on post-acute care and rehabilitation services, which may have been further affected during the pandemic period. These findings serve as a critical warning, highlighting the urgent need for healthcare systems to build robust resilience and sustainable care models that can withstand global crises while managing the complexities of a super-aging society. Further studies incorporating healthcare system capacity and pandemic-related indicators are needed to clarify the mechanisms underlying this temporal association.

While this study benefits from a mandatory nationwide dataset with virtually no loss to follow-up, several limitations must be acknowledged. The exclusion of low-volume facilities and potential seasonal effects of the audit periods may affect the generalizability of certain findings. Moreover, the results reflect a stroke care system with distinctive organizational features, including universal health coverage and centralized quality monitoring. Despite these system-specific characteristics, several observed trends—such as EVT expansion and increased NOAC use—are consistent with international experience and may offer useful insights for other rapidly aging societies, particularly regarding the value of sustained national quality monitoring programs and policy-level reimbursement alignment in translating clinical evidence into real-world practice. Additionally, the reliance on claims data for certain interventions and the lack of detailed clinical history (e.g., specific risk factors) may limit the depth of the causal analysis. Although we performed additional adjustment for CCI score to account for baseline comorbidity burden, residual confounding related to premorbid functional status, frailty, or treatment limitation decisions—particularly among the rapidly increasing very elderly population—cannot be fully excluded. Nevertheless, the unparalleled scale and clinical granularity of the ASQAP database provide robust evidence for the evolving landscape of stroke care in Korea.

Conclusions

Over the past decade, inpatient acute stroke management in South Korea has undergone substantial evolution, characterized by the rapid integration of endovascular thrombectomy for severe IS, a definitive transition to endovascular coiling for SAH, and highly optimized pharmacological care featuring near-universal statin use and the widespread adoption of NOACs and dual antiplatelet therapy. These advancements reflect a highly responsive healthcare system that successfully translates emerging clinical evidence into real-world practice.

However, notable challenges remain regarding the sustainability of these clinical gains. First, the “unexplained discrepancy between ambulance use and arrival time”—where increased emergency transport has not yet translated into improved golden-hour arrival rates—highlights important bottlenecks in the prehospital care continuum. Future policies must move beyond simply increasing ambulance utilization to focus on enhancing EMS triage protocols and optimizing hospital-EMS data linkage to minimize systemic delays.

Furthermore, the non-linear, U-shaped reversal in adjusted mortality following the COVID-19 pandemic highlights the potential vulnerability of the stroke care system in a rapidly superaging society. This reversal underscores the importance of building robust healthcare resilience. To sustain the progress made in stroke outcomes, it is essential to develop scalable care models that can address the complex needs of the oldest-old population while maintaining operational integrity during global health crises.

Supplementary materials

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