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Background: Medical care disparities are wide, and stroke in no exception. Reperfusion therapy is the standard treatment for acute ischemic stroke, but its use may vary across hospitals. Methods: Data from 75,870 patients admitted to 247 acute stroke hospitals nationwide were obtained through the 2013-2018 acute stroke quality evaluation program conducted by the Health Insurance Review and Assessment Service. The primary outcome was the hospital reperfusion therapy rate (RTR), defined as the proportion of intravenous tissue plasminogen activator (IVT) and/or endovascular thrombectomy (EVT) cases in patients potentially eligible for reperfusion therapy (onset-to-arrival time ≤ 6 hours and initial NIHSS score ≥ 4). Hospital RTRs, adjusted for age, sex, onset-to-arrival time, and initial stroke severity, were analyzed with hospital characteristics. Results: During the study period, 10,513 stroke patients were potentially eligible for reperfusion treatment and were admitted to 247 acute care hospitals. The RTR of the study population was 52.9%. The mean hospital RTR was 34.8% [median (IQR) 37.5% (9.8 - 56.2)]. A higher number of beds and average monthly stroke admissions were associated with a higher hospital RTR. Multivariable analysis revealed the average stroke admission per month, presence of stroke unit, the average IVT per month, and the average EVT per month were the independent determinants for hospital RTR. Hospital RTR was inversely correlated with 1-year mortality regardless of hospital stroke volume. Conclusions: RTRs vary widely across hospitals. The higher the hospital stroke volume, the higher the hospital RTRs. High hospital RTRs correlates with low 1-year mortality regardless of hospital stroke volume.

The expected growth of stroke burden in Korea in early 2000s led to the initiation of a government-funded clinical research project with the goal of development and implementation of national stroke guidelines. The CRCS-K (Clinical Research Collaboration for Stroke in Korea) began as a part of this project. For stroke epidemiology and quality of care research, the CRCS-K developed a multicenter, prospective, stroke registry and began collection of data in 2008. Now, about 100 000 cases have been registered at 17 university hospitals or regional stroke centers and about 200 articles have been published based on the registry experience. The analysis of the 10-year secular trends showed overall improvement of stroke care and outcomes and areas for improvement. This large-scale, high-quality dataset provides opportunities to explore and compare treatment disparities using the comparative effectiveness research methods, design and conduct a registry-based randomized clinical trial, connect the registry data with other data sources including the national claims data and neuroimaging or genetic data, and collaborate with other international researchers. An international stroke registry consortium may be a viable future direction.

Objectives: The blood viscosity would quantify the physiological state of abnormal blood flow and hypercoagulability, which are crucial predisposing factors of ischemic stroke. It investigated whether the viscosity increase in the stroke. Methods: It enrolled a series of patients who visited the hospital with any neurologic symptom or sign within 24 h of last well-being. Blood was immediately sampled at the time of hospital arrival as a routine clinical practice along the acute stroke clinical pathway. The viscosity was investigated in a point-of-care test manner using ARS M-200, Rheology Solutions, Korea. It placed the whole blood between the two plates and measured the viscosity by applying a torque of 10 Hz within 5 minutes of taking the blood sample. The primary outcome was an ischemic stroke and other diseases, and the difference in blood viscosity between the two groups was compared. Results: In 2021, it enrolled 47 subjects (age, 69.5 ± 12.9 years-old, male, 51.0%) of whose were diagnosed as ischemic stroke (n = 18) and other diseases (n = 29) consisted of hemorrhagic stroke, metabolic encephalopathy, vertigo, seizure, drug intoxication, and peripheral neuropathy. The viscosity of ischemic stroke with 10 Hz torque was significantly higher than those of non-stroke (22.7 ± 7.4 vs. 18.4 ± 7.0 Ps, P = 0.02). In stroke, the viscosity was significantly different between direct visits (25.5 ± 6.6 Ps) and transferred subjects with intravenous fluids (14.3 ± 1.4) (P = 0.003). In the case of hemorrhagic stroke, traumatic hemorrhage presented the highest values (27.1 ± 5.8), which was different from intracerebral hemorrhage (22.1 ± 7.3 Ps, Figure). Conclusion: The blood viscosity increased in acute ischemic stroke, which would be used as an auxiliary factor in the emergency setting. Also, it may be warranted the following studies for investigating their prognostic roles.

Background: In-hospital and 30-day mortality, 3-month functional outcome were reported as associated with endovascular treatment (EVT) case volume per hospital, but one-year mortality was unknown. Furthermore, the hospital EVT volume threshold based on one-year mortality was not reported. We aimed to investigate whether there was a correlation between annual EVT case volume per hospital and one-year mortality and suggest volume threshold. Methods: Data from Korean national survey for assessing quality of acute stroke care were used. The survey was conducted since 2005 and the subject was patients with acute stroke who were admitted via emergency rooms within 7 days of onset at hospitals treating 10 or more stroke cases during the three (2013, 2014) or six (2016) month survey period. Ischemic stroke cases treated with EVT during the last available three assessments (2013, 2014, and 2016) were selected for the analysis. Results: A total of 1,746 ischemic stroke cases (age, 69.2 ± 12.4years; male, 56.6%) treated in 120 hospitals with EVT were analyzed. The median annual EVT case volume was 12.0 cases per hospital (interquartile range, 6.0-22.9) and the mortality at one-month, three-month, and one-year were 12.7%, 16.6%, and 23.3%, respectively. When divided into quartiles according to the annual EVT case volume, the lowest quartile group was found to have the highest one-year mortality (odds ratio [95% confidence intervals], 1.49 [1.04-2.13]), adjusted for age, sex, NIHSS, onset to arrival time. Restricted cubic splines performed on the annual EVT case volume per hospital revealed that cut-off value for the probability of one-year mortality was 15 cases per year ( p Conclusions: There was an association between annual EVT case volume and one-year mortality, and the volume threshold per hospital based on the one-year mortality was found to be 15 EVT cases per year.

Background and Aims: Robotic rehabilitation therapy has been tried as a novel technology in field of upper extremity rehabilitation of stroke patients. However, the previous trial revealed the additional effect of robotic therapy compared to conservative therapy. We aimed to investigate whether the same intensity robot-assisted arm training(RAT) was more effective on the recovery of motor and improvement of upper limb function than conventional occupational therapy(COT) in subacute first-ever hemiplegic stroke patients (Fig.1). Methods: The clinical assessment included Fugl-Meyer Assessment(FMA), Motricity Index(MI), Functional Independence Measure(FIM), Motor Function Test(MFT), Wolf Motor Function Test(WMFT), Trunk Control Test(TCT), Maximal Voluntary Torques(MVT), Visual Analogue Scale(VAS) for pain, and Active Range of Motion(AROM). The repeated measures ANOVA was used to compare the results of longitudinal analyses between two groups (SPSS Inc., Chicago, IL, USA). Results: The all parameters measured at baseline did not differ between two groups. Both groups showed significant improvements in FMA, MI, FIM, MFT, WMFT, TCT, MVT, and AROM after treatment (P Conclusions: This study did not agree that robot-assisted arm training combined with conventional occupational therapy in subacute post-stroke hemiplegic patients may be superior to the same intensity conventional occupational therapy.

Background: Recent endovascular treatment (EVT) trials suggest the presence of target mismatch profiles up until 24 hours after stroke symptom onset. We aim to a) demonstrate the presence of target mismatch in patients presenting beyond these recent time thresholds and b) potential benefit with EVT in these patients. Methods: Between 01/2012 and 12/2018, patients with AIS with ICA or MCA occlusion and baseline NIHSS score ≥6 arriving ≥16 hours from last known well were identified. CT or MR perfusion images at presentation were evaluated using RAPID software; ischemic core was defined as rCBF Results: Of 154 patients [55% male, mean age 70 ± 13 years, median baseline NIHSS 13 [IQR 8 - 18], 76 (49%) had unwitnessed onset. Median last known well to arrival in hospital time was 42.2 [22.8 - 76.9]. CTP or MR perfusion were obtained in 115 (75%). Median ischemic core volume i.e., 11.0 ml [iqr 0 - 40 ml], and penumbra volume (Tmax >6 s) i.e., 57 ml [16 - 133 ml] and a median mismatch ratio 4.0 [iqr 0.9 - 18.0] were noted. When inclusion criteria of the following trials, namely, ESCAPE, DAWN and DEFUSE3 trial were applied, DAWN-eligible patients were n=45 (29%), DEFUSE3 n= 61 (40%) and ESCAPE n=59 (43%). Figure 1a shows trial eligibility by time from last known well. 24 (16%) patients had EVT. EVT was associated with better functional recovery at 3 months (Figure 1b) for 90-day mRS 0-2 (adjusted OR [95% CI], 8.11 [2.49 - 30.44]) and 90-day mRS shift (common adjusted OR 5.50 [2.33 - 13.29]). Treatment effect with EVT was seen from 16 to 240 hours since last known well (Figure 1c). Parenchymal Hemorrhage type 2 was seen in 13 % offered EVT vs. 3% (adjusted OR 4.11 [0.73 - 21.72]). Conclusions: Patients with anterior circulation LVO presenting very late, even days from last known well, may potentially benefit from EVT.

Introduction: There have been few reports on status of acute stroke management at a national level worldwide, and none in Korea. This study is aimed to describe the current status and disparities of acute stroke management in Korea. Methods: Data from 5th (2013) and 6th (2014) national surveys for assessing quality of acute stroke care were used. Patients with principal diagnosis codes indicating subarachnoid hemorrhage (SAH), intracerebral hemorrhage (ICH), ischemic stroke (IS), who were admitted via emergency rooms within 7 days of onset at hospitals treating 10 or more stroke cases during the each 3-month survey period were selected. Results: A total of 19,608 stroke cases (age, 67.7±13.5years; female, 45%; IS, 76%; ICH, 15%; SAH, 9%) treated in 216 hospitals were analyzed. Thirty-one percent of hospitals had stroke units and 41% of stroke cases were treated at hospitals without stroke units. In IS, IV thrombolysis (IVT) and endovascular treatment (EVT) rates were 10.7% and 3.6%, respectively. Thirty-nine percent of IVT and fifty-two percent of EVT cases were performed in hospitals with annual volume of Conclusions: This study is the first report on the status of acute stroke care in Korea on a national level. Large number of recanalization therapies were performed in low-volume-hospitals. Expansion of stroke unit service, stroke center certification or accreditation, and connections between stroke centers and EMS are highly recommended.

Backgrounds: Irrespective of the indication for statin, statin adherence after ischemic stroke was associated with better clinical outcome. We studied the association between statin adherence and recurrent cardiovascular (CV) events among the patients with acute ischemic stroke and statin benefit. Methods: Using Comprehensive Registry Collaboration for Stroke in Korea (CRCS-K), patients with acute ischemic stroke were identified. Statin benefit was defined using the secondary prevention guidelines of American Stroke Association in 2014. The data for statin prescription after discharge were obtained from National Health Insurance Services (NHIS) claim data by matching with CRCS-K. Statin adherence was measured by the medication possession ratio (MPR), which was dichotomized, setting a threshold of MPR ( Results: Among 11,768 patients in NHIS-CRCS-K matching database, 5,504 patients were the statin benefit group and prescribed with statin on discharge. Overall MPR for 1 year after discharge was 73.1%. Overall CV events for 1 year were 569, which was more prevalent in low adherence group. (MPR Conclusion: Adequate statin adherence in the patients with acute ischemic stroke and statin benefit was significantly associated with recurrent CV events.

Background: Carotid intraplaque hemorrhage (IPH) is well known for a risk indicator for thromboembolism, but not easy to detect it rapidly in acute symptomatic carotid disease. The aim of this study was to assess usefulness of time-of-flight (TOF) MRA for the detection of IPH in patients with acute symptomatic carotid diseases. Methods: We retrospectively identified consecutive patients with acute symptomatic carotid disease who were admitted within 12 hours after stroke onset. Fifty-nine patients underwent TOF MRA at admission and were divided according to the presence of intraplaque high signal intensity (HSI). The severity of carotid stenosis and diffusion weighted imaging (DWI) MRI lesion patterns were evaluated. Results: Intraplaque HSI was detected in 28.8% of total enrolled patients (17/59). Mild to moderate symptomatic carotid stenosis was more in the intraplaque HSI positive group (70.6%) than the intraplaque HSI negative group (42.8%) (p=0.025). The patients with intraplaque HSI more frequently demonstrated disseminated small infarction pattern (76.5% in the intraplaque HSI positive, 47.6% in the negative group), and did not show border-zone infarction pattern (0% in the positive, 16.7% in the negative group). Conclusion: TOF MRA in acute symptomatic carotid disease may be noninvasive and rapid tool to detect the IPH. The IPH was common in smaller degree of carotid stenosis and demonstrated disseminated small infarction pattern. Intraplaque HSI on TOF MRA in acute symptomatic carotid disease may help determine the mechanism of stroke and establish treatment plan early.

Introduction: Higher quality of stroke care based on guideline recommendations is associated with better clinical outcomes. However, there is limited information about contemporary status of quality of stroke care and its association with improvements in clinical outcomes in Korea. Methods: This retrospective observational study was performed by analyzing the data of the patients admitted to 258 acute stroke care hospitals covering an entire country from the Acute Stroke Quality Assessment Program, which was carried out by the Health Insurance Review and Assessment Service from 2008 to 2014. Six GWTG-Stroke performance measures (except prophylaxis for venous thromboembolism) were applied to evaluate quality of stroke care in Korea. The primary outcome variable was defect-free care, which is defined as the proportion of patients who received all of the performance measure interventions for which they were eligible. Multivariable analysis was performed to evaluate the association between defect-free care and clinical outcomes. Temporal trends and hospital variations of performance measures were evaluated. Results: Among 43 793 patients (mean age, 67±14 years; male, 55%) with acute stroke during the study period, 31 915 (72.9%) patients were hospitalized due to ischemic stroke or transient ischemic attack. The proportion of defect-free care for stroke steadily increased throughout the study period: from 80.2% in 2008 to 92.1% in 2014. Defect-free care was given more frequently in patients admitted to hospitals with a higher volume of stroke cases or intravenous thrombolysis administration, and stroke units. Patients who received defect-free care were associated with discharge to home (adjusted odds ratio 1.96; 95% CI 1.78-2.16) and 1-year survival (adjusted odds ratio 0.41; 95% CI 0.37-0.46). Only 60% of stroke patients were managed in hospitals with a certified stroke unit, and the distribution of certified stroke units showed an urban-to-rural gradient. Conclusions: The quality of stroke care in Korea has improved over time, and defect-free care was associated with discharge to home and 1-year mortality. There are still opportunities to improve the quality of stroke care in Korea by development of stroke networks in Korea.

Introduction: Remnant cholesterol, comprising triglycerides(TG)-rich lipoproteins, accumulates in intimal foam cells and causes atherosclerosis. Fasting TG is reported to be associated with atherosclerotic stroke, but relationships between non-fasting TG (NFTG) and ischemic stroke subtypes are unknown. Recently NFTG was found to produce endothelial dysfunction. This study aimed to elucidate the association of fasting and NFTG with ischemic stroke subtypes, especially large-artery atherosclerosis (LAA) and small vessel occlusion (SVO). Methods: Using a prospective multicenter stroke registry (Clinical Research Center for Stroke - 5th division), we identified acute ischemic stroke patients, hospitalized within 48 hours of onset, and whose fasting and non-fasting TG values were available. We measured lipid profiles in each individual twice; at presentation and after overnight fasting. Initial TG were regarded as NFTG when measured within 8 hours from last mealtime. Results: Total 3,170 patients were analyzed. Stroke subtypes were categorized as LAA (37.9%), SVO (18.7%) and non-LAA and non-SVO (43.4%). Lipid levels according stroke subtypes are presented in Table. Lipid levels were divided by quartiles and the highest quartile was compared to others. In multinomial analyses compared to non-LAA and non-SVO group, fasting TG was associated with LAA (adjusted ORs 1.33 [95% CIs 1.09 - 1.62]) and SVO (1.61 [1.27 - 2.04]). NFTG was associated not with LAA (1.05 [0.87 - 1.28]), but with SVO (1.36 [1.08 - 1.71]). With respect to other lipid levels, fasting and non-fasting LDL were associated with both LAA (1.57 [1.29 - 1.90], fasting; 1.89 [1.56 - 2.29], non-fasting) and SVO (1.40 [1.11 - 1.77], fasting; 1.74 [1.38 - 2.19], non-fasting). Conclusions: This study may be the first one to demonstrate an association between non-fasting TG and SVO. It should be explored further on mechanisms of differential effect of fasting and non-fasting TG on ischemic stroke subtypes.

Introduction: Susceptibility vessel sign (SVS) on T2*-weighted imaging (T2*WI) is associated with a high proportion of RBCs. Susceptibility weighted imaging (SWI) is more sensitive to visualize SVS than T2*WI, resulting both RBC- and platelet-rich thrombi detectable. Clot composition and burden impact the success of recanalization therapy, but how SVS influences the likelihood of recanalization is still debated. Hypothesis: We assessed the hypothesis that increased conspicuity of SWI-SVS reflects high proportion of RBCs and subsequent recanalization by endovascular treatment. Methods: From total of 143 ischemic stroke patients who was performed endovascular treatment between February 2010 and June 2015, the authors collected eligible cases with the following inclusion criteria; (1) SWI performed before endovascular treatment (N=123); (2) intracranial portion of ICA, MCA, and ACA occlusion (N=93). We excluded 4 cases with SWI of poor quality and analyzed 89 cases. Clinical information including stroke subtype, use of rt-PA, and time from puncture to recanalization was analyzed. All MR images and angiographies were analyzed for the presence, location, diameter, length, and volume (diameter*length) of SWI-SVS, and TICI grade. Results: Female was 47.2% (n=42) and mean age was 68.4±13.2. SWI-SVS was identified in 77.5% (n=69) of patients. SWI-SVS was more commonly associated with cardioembolism (CE; 49 of 57, 86.0%) than with other stroke subtypes (20 of 32, 62.5%; P =0.011). SVS length (11.20±7.96 vs. 6.90±7.03 mm; P =0.013) and diameter (4.72±2.53 vs. 2.48±2.21 mm; P P =0.040). Multivariate analysis showed that SVS diameter and volume were independent predictors of CE and recanalization, respectively (OR, 1.67 and 1.02; 95% CI, 1.15-2.41 and 1.00-1.04; P =0.007 and 0.005). Conclusions: Diameter and volume of SWI-SVS can predict cardioembolic stroke and recanalization, respectively. It may be useful for choosing the optimal treatment based on clot composition.

Aim: Ceria nanoparticles (NPs) are potent anti-oxidants because of their small size and surface characteristics. In addition to this, they have anti-inflammatory effects. However, their effects on post-stroke inflammation have not been evaluated in experimental intracerebral hemorrhage (ICH). Methods: Ceria NPs were made by a modified double-decomposition method. RAW 264.7 macrophages (MΦs) were activated by 30% hemolysate from blood by checking morphology and inflammatory products. They were treated by 0.125 mM ceria NPs or not. Overall reactive oxygen species (ROS) after the activation of MΦs were measured by oxidized DCF-DA in FACS. Inflammatory cytokines, IL-1β and TNF-α, were evaluated by ELISA, and inflammatory end-products, COX2 and iNOS, were done by Western blots. Animal ICH was induced by the stereotactic injection of collagenase into the rat brain, and ceria NPs were injected intravenously. Water contents were measured by wet and dry weights of brain after induction of ICH. We calculated hematoma volumes by an image-analyzer and the recruitment of MΦs in perihematomal area by the immunofluorescent staining using CD68 antibody. Results: Ceria NPs were made as 3-nm small sized, uniform round-shaped, and well-dispersed agents, which were suitable for biomedical applications. Ceria NPs reduced oxidized DCF-DA (a marker of overall ROS) after hemolysate-induced activation of MΦs (ceria-treated group, 391 unit vs. control, 567 unit, P=0.03). In this in vitro hemorrhage model, MΦs secreted less cytokines, IL-1β and TNF-α, in ceria-treated group than control, and in Western blots, the expression of COX2 and iNOS decreased in ceria group compared to control. In rat ICH model, ceria NPs reduced water contents in hemorrhagic hemisphere, which is closely related to perihematomal inflammation (0.5 mg/kg ceria group, 79,9% vs. control, 81.1%, P=0.01). Although hematoma volumes were not different between two groups, the CD68-positive MΦs in immunofluorescent staining were less recruited into the perihematomal area in ceria-treated group than control. Conclusion: Ceria NPs decreased inflammation after ICH in both in vitro and in vivo models. From these anti-inflammatory effects, they could be potential therapeutic agents in acute period after ICH.

Background: Association between family history of stroke and stroke recurrence remains unclear. Methods: Using a web-based multicenter stroke registry database, information on history of stroke in first-degree relatives was collected prospectively in ischemic stroke patients hospitalized within 7 day of onset. Collected information was categorized as follows: type of affected relatives with stroke (paternal, maternal, sibling, or two or more) and age of relative’s stroke onset in relative (< 50, 50∼59, 60∼69, and ≥ 70). Stroke recurrence was captured prospectively using predetermined protocol. Subgroup analysis was performed using categories based on patient’s age at the index stroke. Results: Among 7,642 patients, 937 (12.3%) had history of stroke in their first-degree relatives, and 475(6.2%) experienced stroke recurrence (median follow-up, 365 days). In multivariate Cox proportional hazard models, overall family history was not associated with stroke recurrence (hazard ratio [HR], 1.06; 95% confidence interval [CI], 0.80-1.41). However, the details of family history, including relative’s age at stroke onset < 50 (HR, 2.15; 95% CI, 1.01-4.57) and stroke history in sibling (HR, 1.67; 95% CI, 1.09-2.57) were independently associated with stroke recurrence after adjusting for possible confounders. The associations seemed to be stronger in stroke of young adults (age, Conclusion: This study suggests that having relative with early onset stroke and sibling with history of stroke increase the risk of recurrent stroke and imply that additional precautions may be needed in such population.

Background: Red thrombi, composed of fibrin and trapped erythrocytes, have magnetic susceptibility effect. Susceptibility vessel sign (SVS) is visualized more sensitively using susceptibility weighted imaging (SWI) than T2*-weighted imaging. Bright vessel appearance (BVA) on arterial spin labeling (ASL) imaging can visualize occluded arterial segment by arterial transit artifact, more sensitively in small and peripheral branches. We investigated the usefulness of SWI-SVS with BVA to visualize different thrombus and predict stroke mechanisms. Methods: From a total of 564 stroke cases who admitted to Seoul National University Hospital in 2014, the authors collected eligible cases with the following inclusion criteria; (1) Lesion-documented ischemic stroke (N=425); (2) SWI and ASL MRI performed (N=407); (3) Symptomatic arterial occlusion with BVA (N=141). All images were analyzed for the presence and location of SWI-SVS and BVA. The location of SWI-SVS and BVA were classified into (1) proximal, large arteries; distal ICA, M1/2, A1, P1, basilar artery, V4 and (2) peripheral, small arteries; M3/4, P2/3, A2/3, lenticulostriate arteries, three cerebellar arteries. The relationships between SWI-SVS in the presence of BVA and stroke etiologies are explored. Results: Male was 58.2% (n=82) and mean age was 65.7±14.3. Thirty-four percent (n=48/141) of BVA and 30.3% (n=30/99) of SVS was located within small, peripheral arteries. SWI-SVS was more commonly associated with other determined etiology (20.2% vs. 4.8%) and cardioembolism (39.4% vs. 14.3%), but less with large artery atherosclerosis (26.3% vs. 69.0%, P Conclusions: SWI-SVS with BVA may predict ischemic stroke of cardioembolism and other determined etiology. Occlusions of small, peripheral arteries are well visualized with BVA and composition of thrombus can be identified by SWI-SVS.

Introduction: Antiplatelets are the most important drugs to prevent ischemic stroke. These drugs are prescribed for nearly life long period. However, few studies have elaborated on the significance of adherence with antiplatelet monotherapy in ischemic stroke. Methods: We enrolled 36,128 patients with ischemic stroke from Jan 2008 through Dec 2011 from 40 hospitals which were participated in a nationwide research project in Korea. The whole drug information was obtained from the Health Insurance Review and Assessment Service in Korea. Among them, 8,299 patients had taken antiplatelet monotherapy over 6 months with one of the most popular antiplatelet drugs (aspirin, clopidogrel or cilostazol). The adherence with antiplatelet monotherpay was defined as % adherence = (n of days’ supply) / (actual n of days to refill) х 100. Nonadherence was defined as < 80% adherence. The mortality and drug information were censored on 31 Dec 2012. Results: From 8,299 patients using a single antiplatelet drug over 6 months, 1056 (12.7%) patients were included in nonadherence group. The factors related to nonadherence were severe neurological deficits and the atherosclerotic stroke subtype. Compared with the good adherence group, the adjusted hazard ratio (HR) of the nonadherence group for all-cause mortality was 1.49 (95% CI, 1.28-1.73), after controlling age, stroke severity, stroke subtype, and the presence of hypertension, diabetes, hyperlipidemia, and smoking. In subgroup analyses, the adjusted HRs for mortality after ischemic stroke were increased in the aspirin or clopidogrel monotherapy group respectively, compared with good adherence group (HR and 95% CI in nonadherence with aspirin, 1.22 and 1.01-1.46; HR and 95% CI in nonadherence with clopidogrel, 2.07 and 1.53-2.82). Conclusion: Our study demonstrated that nonadherence with antiplatelet monotherapy is an independent predictor of all-cause death after ischemic stroke from nationwide multicenter follow-up study.

Background and Purpose— The new pooled cohort risk (PCR) equations is sex- and race-specific estimates of the 10-year risk of atherosclerotic cardiovascular events among disease-free adults. Little is known about the association between the PCR model and presence of silent brain infarction (SBI). Methods— We conducted a cross-sectional study of 1603 neurologically asymptomatic Korean people (mean age, 56.6±8.3; 838 men), who underwent brain MRI. We explored the association of PCR with SBI by race. SBI was divided into deep subcortical and hemispheric (hs-SBI). Results— One-hundred seventy-five (10.9%) subjects had SBI. The PCR as white was independently related to the presence of SBI (odds ratio, 1.06; 95% confidence interval, 1.04–1.09), multiple (≥2) SBIs (1.09; 1.05–1.12), deep subcortical SBI (1.06; 1.04–1.09), and hs-SBI (1.07; 1.02–1.11). Compared with the lowest PCR category ( Conclusions— Discrimination was fairly compatible with each race model. The PCR might serve as a simple clinical tool for identifying people at high risk for the untoward consequences of SBI, particularly multiple SBIs and hs-SBI.

Background and purpose: Fimasartan is a novel angiotensin receptor blocker (ninth), and its safety and efficacy have been established as an antihypertensive drug. Anti-apoptotic or anti-inflammatory effects of angiotensin receptor blockers were reported. However, few studies have elaborated on the effects of long-term treatment with low-dose ARB on cerebral ischemia independent of blood pressure lowering. Methods: Noninvasive blood pressure monitoring was performed in Sprague-Dawley rats which 0.5 mg/kg of fimasartan or phosphate-buffered saline (PBS) were administered for 4 weeks. Fimasartan (0.5, 1 or 3 mg/kg) was administered intraorally for 4 weeks, and we induced ischemia-reperfusion injury in rats. Infarct volume and the number of TUNEL-positive apoptotic cells were measured at 7 days. Functional outcomes were evaluated by modified limb placing test. To identify the anti-inflammatory effect of fimasartan, the number of inflammatory cells (OX6-positive cells) was measured. To identify mediators, phospho-STAT3 and IkB proteins were measured via Western blot analyses at 48 hours. Results: Blood pressures were decreased after administration of 1 mg/kg or 3 mg/kg of fimasartan for 4 weeks, but were not decreased in 0.5 mg/kg group. All doses of fimasartan decrease infarct volumes, and low-dose fimasartan (0.5 mg/kg) maximally reduced infarct volume up to 70% of those of the control group ( p < 0.05). Quantitative analysis showed that the number of TUNEL-positive cells was remarkably decreased in the low-dose fimasartan group (622 ± 57 cell/mm 3 vs. 235 ± 48 cells/mm 3 ; p < 0.05). Low-dose fimasartan improved functional outcomes at 14 days (74% recovery in fimasartan group vs. 43% in control group; p < 0.05). The low-dose fimasartan group exhibited a lower number of OX6-positive cells (fimsartan group: 157 ± 17 cells/mm 3 ; control: 86 ± 11 cell/mm 3 ; p < 0.05). The IkB degradation as a marker of NF-kB activation, was delayed, and phospho-STAT3 was decreased in the low-dose fimasartan group ( p < 0.05). Conclusion: We demonstrate that long-term treatment with fimasartan improves neurological outcome in transient focal ischemia in rats. This protective effect of fimasartan is independent blood pressure lowering.

Background: Chronic kidney disease (CKD) increases risk of cardiovascular diseases, which might be mediated by facilitation of atherosclerosis. However, impact of CKD on progression of atherosclerosis has not been fully evaluated, and we sought to investigate associations between CKD and extent of carotid atherosclerosis. Methods: Between January 2009 and February 2013, we enrolled a consecutive series of 147 CKD patients and compared the same number of age, sex and vascular risk factor-matched 147 control subjects who visited our hospital during the same period. Carotid atherosclerosis was examined with MR angiography of internal carotid artery (ICA). The degree of stenosis of the internal carotid artery (ICA) in each patient was classified into 5 grades; (1) normal; (2) mild ( Results: Mean age of the subjects was 72.2±8.7 years, and 208 were male (70.7%) among the total of 294 subjects. Significant stenosis of ICA (stenosis more than 50%) was more prevalent in CKD patients [odds ratio (OR) 6.7; 95% confidence interval (CI) 2.2-20.4, p=0.001). The presence of CKD was an independently risk factor for increasing the severity of stenosis of ICA (mild, OR 4.5, 95% CI 2.0-10.2; moderate, OR 3.9, 95% CI 1.3-22.4; severe, OR 12.0, 95% CI 4.3-34.6; occlusion, 14.1, 95% CI 2.1-92.2). Conclusion: In the current case-control study, we found that CKD is associated with incidence of significant carotid stenosis and increases the severity of carotid stenosis. Our results indicate that CKD should be treated as a new risk factor for carotid atherosclerosis.

Background and purpose: Warfarin is one of the most important prevention drugs against ischemic stroke. Factors influencing on warfarin adherence in patients with atrial fibrillation have been investigated. However, few studies have elaborated on the significance and related factors of warfarin adherence in patients with ischemic stroke or transient ischemic attack (TIA). Methods: A total of 46,219 patients with ischemic stroke or TIA were enrolled from October 2007 through December 2011 in Clinical Research Center for Stroke as a nationwide project in Korea. The morality information of all patients was based on computerized searches of death certificate data from the “Statistics Korea” of the Korean National Statistical Office, and the whole drug information was obtained from the Health Insurance Review Assessment and Review Service in Korea. Among them, warfarin was prescribed for 5,660 patients over 6 months. Warfarin adherence was defined as % adherence = (n of days’ supply) / (actual n of days to refill) х 100. Nonadherence was defined as < 80% adherence. We censored the mortality data on 31 December 2012. Results: From 5,660 patients using warfarin over 6 months, 801 patients (14.2%) were included in nonadherence group. The factors related to nonadherence for warfarin ware theses: old age, increased stroke severity, and the presence of diabetes or hyperlipidemia. Based on Cox regression analysis, compared with good adherence group, the adjusted hazard ratio (HR) of the nonadherence group for all-cause of mortality were 1.46 (95% confidence interval, 1.24 – 1.72) after controlling old age, stroke severity, and the presence of diabetes, hypertension, hyperlipidemia, and smoking. The presence of diabetes also predicted all-cause death after stroke independently in patients using warfarin over 6 months (adjusted HR, 1.28 ; 95% confidence interval, 1.10 – 1.49). Conclusion: Our study demonstrated that nonadherence for warfarin is independent predictor of all-cause death after ischemic stroke or TIA from nationwide multicenter follow-up study. The related factors to nonadherence for warfarin were old age, increased stroke severity, and the presence of diabetes or hyperlipidemia.

Background: Vascular calcification is strongly associated with cardiovascular morbidity and mortality by reducing arterial elastance. Recently alkaline phosphatase (ALP) is identified as the critical factor for vascular calcification, but no clinical studies investigating relevance of ALP and cerebral atherosclerosis have been reported. In this study, we assessed the hypothesis that increased levels of serum ALP may be associated with severity of cerebral atherosclerosis. Methods: From October 2010 to March 2012, we prospectively included total 518 patients (313 men/205 women) aged 25-96 years with acute ischemic stroke. Cardioembolic stroke patients were excluded because of the interference by acute arterial embolic occlusion. The patients were divided by baseline measurements into quantiles of ALP levels (90 IU/L). Bilateral middle cerebral arteries, distal internal carotid arteries and basilar artery were selected for the evaluation of intracranial atherosclerosis, bilateral proximal internal carotid arteries and common carotid arteries for the extracranial atherosclerosis. We defined significant arterial stenosis as moderate or more stenosis (50-100%) evaluated by at least one angiographic study using MR angiography, CT angiography or digital subtraction angiography. Statistical analyses were performed using the multivariate logistic regression analysis adjusted for age, gender, hypertension, diabetes, dyslipidemia, smoking, presence of secondary prevention, serum calcium levels. Results: In the multivariate logistic regression analysis, compared with the first ALP quantile, adjusted odds ratio of the third and fourth quantiles for significant intracranial atherosclerosis were 2.30 (95% confidence interval 1.06-5.01) and 3.84 (1.78-8.30). There was no significant correlation between ALP levels and significant extracranial atherosclerosis. Conclusions: In conclusion, our study demonstrated that increased serum levels of ALP are an independent risk factor for significant intracranial atherosclerosis.