Jae-Kwan Cha

Pre-hospital notification reduced the door-to-needle time for iv t-PA in acute ischaemic stroke

Background and purpose:  Intrahospital delay is the most serious obstacle in thrombolysis in acute ischaemic stroke (AIS). We implemented the pre‐hospital notification system from the emergency medical information system in our metropolitan area to reduce intrahospital delay.

MRI-based Algorithm for Acute Ischemic Stroke Subtype Classification

Background and Purpose In order to improve inter-rater reliability and minimize diagnosis of undetermined etiology for stroke subtype classification, using a stroke registry, we developed and implemented a magnetic resonance imaging (MRI)-based algorithm for acute ischemic stroke subtype classification (MAGIC). Methods We enrolled patients who experienced an acute ischemic stroke, were hospitalized in the 14 participating centers within 7 days of onset, and had relevant lesions on MR-diffusion weighted imaging (DWI). MAGIC was designed to reflect recent advances in stroke imaging and thrombolytic therapy. The inter-rater reliability was compared with and without MAGIC to classify the Trial of Org 10172 in Acute Stroke Treatment (TOAST) of each stroke patient. MAGIC was then applied to all stroke patients hospitalized since July 2011, and information about stroke subtypes, other clinical characteristics, and stroke recurrence was collected via a web-based registry database. Results The overall intra-class correlation coefficient (ICC) value was 0.43 (95% CI, 0.31-0.57) for MAGIC and 0.28 (95% CI, 0.18-0.42) for TOAST. Large artery atherosclerosis (LAA) was the most common cause of acute ischemic stroke (38.3%), followed by cardioembolism (CE, 22.8%), undetermined cause (UD, 22.2%), and small-vessel occlusion (SVO, 14.6%). One-year stroke recurrence rates were the highest for two or more UDs (11.80%), followed by LAA (7.30%), CE (5.60%), and SVO (2.50%). Conclusions Despite several limitations, this study shows that the MAGIC system is feasible and may be helpful to classify stroke subtype in the clinic.

Cognitive Impairment Evaluated With Vascular Cognitive Impairment Harmonization Standards in a Multicenter Prospective Stroke Cohort in Korea

Background and Purpose— Since the Vascular Cognitive Impairment Harmonization Standards (VCIHS) neuropsychological test protocol was proposed by the National Institute of Neurological Disorders and Stroke and Canadian Stroke Network, no studies have applied this neuropsychological protocol to poststroke survivors in a large-scale, multicenter stroke cohort. We determined the frequency of vascular cognitive impairment (VCI) and investigated the feasibility of using the Korean version of the VCIHS neuropsychological protocol in a multicenter, hospital-based stroke cohort in Korea. Methods— We prospectively enrolled 620 subjects with ischemic stroke within 7 days of symptom onset among 899 patients who were consecutively admitted to 12 university hospitals in Korea. Neuropsychological assessments using the 60-minute Korean VCIHS neuropsychological protocol were administered at 3 months after stroke. Results— Of the 620 patients, 506 were followed up at 3 months after stroke. Of these, 353 (69.8%) were evaluated for cognitive function using the 60-minute Korean VCIHS neuropsychological protocol. The frequency of VCI at 3 months was 62.6%: VCI with no dementia in 49.9% and vascular dementia in 12.7%. Old age (P=0.014), poor functional outcomes at 3 months (P=0.029), and stroke subtypes other than small vessel disease (P=0.004) were independent risk factors of VCI. Conclusions— VCI, evaluated using the Korean VCIHS neuropsychological protocol, is substantial at 3 months after ischemic stroke in Korea. The use of the 60-minute Korean VCIHS neuropsychological protocol was feasible in large-scale multicenter studies.

The iScore Predicts Functional Outcome in Korean Patients With Ischemic Stroke

Background and Purpose— Several stroke risk scores for prediction of functional outcome have been developed, but rarely validated in Asian populations. We assessed the validity of the iScore, recently developed from Canadian stroke population, in an Asian stroke population from Korea. Methods— We applied the iScore to 4061 eligible participants with acute ischemic stroke in the nationwide multicenter stroke registry in Korea. The main outcome was poor functional outcome defined as having a modified Rankin Scale 3 to 6 at 3 months after stroke onset. The secondary outcome was death at 3 months. C-statistics were calculated to assess performance of the iScore. Results— Poor functional outcome was found in 1496 patients (36.8%), whereas death at 3 months occurred in 294 patients (7.2%). C-statistics were 0.819 (95% confidence interval, 0.805–0.833) for poor functional outcome and 0.861 (95% confidence interval, 0.840–0.883) for death. Overall, there was a high correlation between observed and expected outcomes for poor functional outcome (Pearson correlation coefficient, r=0.990) and for death (r=0.969) according to risk score. Conclusions— The iScore reliably predicts poor functional outcome or death at 3 months after stroke in Korean patients.

Gender differences in the age-stratified prevalence of risk factors in Korean ischemic stroke patients: a nationwide stroke registry-based cross-sectional study

Background Although ethnic or cultural differences affect prevalence of cardiovascular risk factors, limited information is available about the age- and gender-stratified prevalence of the risk factors in Asian stroke population. Aims and hypothesis We assessed gender- and age-stratified prevalences of major risk factors in Korean stroke patients, and assumed that the gender differences are attenuated by adjustment with lifestyle factors. Methods Using the nationwide hospital-based stroke registry, we identified 9417 ischemic stroke patients admitted between April 2008 and January 2011. Prevalence of hypertension, diabetes, hyperlipidemia, atrial fibrillation, prior stroke, and coronary heart disease was assessed in both genders by age groups. We analyzed gender differences of the prevalence among the age groups by calculating prevalence ratio, and further explored the influence of lifestyle factors on the gender difference in multivariable analyses. Results Hypertension and hyperlipidemia were more common in men until middle age, but after that more common in women, whereas diabetes was more common in women after 65 years of age. Atrial fibrillation increased steadily with age in both genders but was more common in women through all age groups. Prior stroke and coronary heart disease showed inconsistent gender differences. Gender differences in hypertension and diabetes among the age groups were attenuated by adjustment with accompanying risk factors including lifestyle factors. Conclusion Korean women with stroke had more hypertension and hyperlipidemia after middle age, more diabetes after 65 years, and more atrial fibrillation throughout all ages. Strategies to control risk factors in women at risk for stroke are eagerly needed.

Efficacy of early administration of escitalopram on depressive and emotional symptoms and neurological dysfunction after stroke: a multicentre, double-blind, randomised, placebo-controlled study.

BACKGROUND Mood and emotional disturbances are common in patients with stroke, and adversely affect the clinical outcome. We aimed to evaluate the efficacy of early administration of escitalopram to reduce moderate or severe depressive symptoms and improve emotional and neurological dysfunction in patients with stroke. METHODS This was a placebo controlled, double-blind trial done at 17 centres in South Korea. Patients who had had an acute stroke within the past 21 days were randomly assigned in a 1:1 ratio to receive oral escitalopram (10 mg/day) or placebo for 3 months. Randomisation was done with permuted blocks stratified by centre, via a web-based system. The primary endpoint was the frequency of moderate or severe depressive symptoms (Montgomery-Åsberg Depression Rating Scale [MADRS] ≥16). Endpoints were assessed at 3 months after randomisation in the full analysis set (patients who took study medication and underwent assessment of primary endpoint after randomisation), in all patients who were enrolled and randomly assigned (intention to treat), and in all patients who completed the trial (per-protocol analysis). This trial is registered with ClinicalTrials.gov, number NCT01278498. FINDINGS Between Jan 27, 2011, and June 30, 2014, 478 patients were assigned to placebo (n=237) or escitalopram (n=241); 405 were included in the full analysis set (195 in the placebo group, 210 in the escitalopram group). The primary outcome did not differ by study group in the full analysis set (25 [13%] patients in the placebo group vs 27 [13%] in the escitalopram group; odds ratio [OR] 1·00, 95% CI 0·56-1·80; p>0·99) or in the intention-to-treat analysis (34 [14%] vs 35 [15%]; OR 1·01, 95% CI 0·61-1·69, p=0·96). The study medication was generally well tolerated; the most common adverse events were constipation (14 [6%] patients who received placebo vs 14 [6%] who received escitalopram), muscle pain (16 [7%] vs ten [4%]), and insomnia (12 [5%] vs 12 [5%]). Diarrhoea was more common in the escitalopram group (nine [4%] patients) than in the placebo group (two [1%] patients). INTERPRETATION Escitalopram did not significantly reduce moderate or severe depressive symptoms in patients with acute stroke. FUNDING Dong-A Pharmaceutical and Ministry for Health, Welfare, and Family Affairs, South Korea.

Recurrent Ischemic Lesions After Acute Atherothrombotic Stroke: Clopidogrel Plus Aspirin Versus Aspirin Alone

Background and Purpose— In patients with acute ischemic stroke caused by large artery atherosclerosis, clopidogrel plus aspirin versus aspirin alone might be more effective to prevent recurrent cerebral ischemia. However, there is no clear evidence. Methods— In this multicenter, double-blind, placebo-controlled trial, we randomized 358 patients with acute ischemic stroke of presumed large artery atherosclerosis origin within 48 hours of onset to clopidogrel (75 mg/d without loading dose) plus aspirin (300-mg loading followed by 100 mg/d) or to aspirin alone (300-mg loading followed by 100 mg/d) for 30 days. The primary outcome was new symptomatic or asymptomatic ischemic lesion on magnetic resonance imaging within 30 days. Secondary outcomes were 30-day functional disability, clinical stroke recurrence, and composite of major vascular events. Safety outcome was any bleeding. Results— Of 358 patients enrolled, 334 (167 in each group) completed follow-up magnetic resonance imaging. The 30-day new ischemic lesion recurrence rate was comparable between the clopidogrel plus aspirin and the aspirin monotherapy groups (36.5% versus 35.9%; relative risk, 1.02; 95% confidence interval, 0.77–1.35; P=0.91). Of the recurrent ischemic lesions, 94.2% were clinically asymptomatic. There were no differences in secondary outcomes between the 2 groups. Any bleeding were more frequent in the combination group than in the aspirin monotherapy group, but the difference was not significant (16.7% versus 10.7%; P=0.11). One hemorrhagic stroke occurred in the clopidogrel plus aspirin group. Conclusions— Clopidogrel plus aspirin might not be superior to aspirin alone for preventing new ischemic lesion and clinical vascular events in patients with acute ischemic stroke caused by large artery atherosclerosis. Clinical Trial Registration— URL: http://www.clinicaltrials.gov. Unique identifier: NCT00814268.

Establishment of Government-Initiated Comprehensive Stroke Centers for Acute Ischemic Stroke Management in South Korea

Background and Purpose— In 2008, the Ministry of Health and Welfare of South Korea initiated the Regional Comprehensive Stroke Center (CSC) program to decrease the incidence and mortality of stroke nationwide. We evaluated the performance of acute ischemic stroke management after the Regional CSC program was introduced. Methods— The Ministry of Health and Welfare established 9 Regional CSCs in different provinces from 2008 to 2010. All Regional CSCs have been able to execute the critical processes independently for stroke management since 2011. The Ministry of Health and Welfare was responsible for program development and financial support, the Regional CSC for program execution, and the Korea Centers for Disease Control and Prevention for auditing the execution. We analyzed prospectively collected data on the required indices from 2011 and repeated the analysis the following year for comparison. Results— After the Regional CSCs were established, the first brain image was taken within 1 hour from arrival at the emergency room for all patients with stroke; the length of hospital stay decreased from 14 to 12 days; for the rapid execution of thrombolysis, the first brain image was taken within 12 minutes; intravenous and intra-arterial thrombolysis were started within 40 and 110 minutes, respectively, after emergency room arrival; and the hospital stay of thrombolytic patients decreased from 19 to 15 days. Conclusions— The Regional CSC program has improved the performance of acute stroke management in South Korea and can be used as a model for rapidly improving stroke management.

ADP-induced platelet aggregation in acute ischemic stroke patients on aspirin therapy

Background and purpose:  Aspirin is an important therapeutic regimen to prevent the recurrent ischemic events or death after acute ischemic stroke. In this study, we evaluated the relationship between the extent of adenosine diphosphate (ADP) ‐induced platelet aggregation and outcome in acute ischemic stroke patients on aspirin therapy.

Symptomatic steno-occlusion in patients with acute cerebral infarction: prevalence, distribution, and functional outcome.

Background and Purpose Symptomatic steno-occlusion (SYSO) in acute ischemic stroke has a significant impact on treatment options and prognosis. However, the prevalence, distribution, clinical characteristics, and outcome of SYSO are not well known. Methods We retrospectively identified 3,451 patients hospitalized because of ischemic stroke within 24 hours of symptom onset at 9 stroke centers in South Korea. Patients who did not undergo magnetic resonance imaging were excluded. SYSO was defined as stenosis or occlusion of cerebral arteries with relevant ischemic lesions in the corresponding arterial territory. The number, location, and severity of SYSOs and their effects on functional outcome were analyzed. Results In total, 1,929 of 3,057 subjects (63.1%) had SYSO. The most frequently affected vessels were the middle cerebral artery (34.6%), extracranial internal carotid artery (14%), vertebral artery (12.4%), and basilar artery (8.7%). SYSO predicted poor outcome on the modified Rankin Scale 3-6 (odds ratio, 1.77; 95% confidence interval, 1.46-2.15) with adjustments. Involvement of 2 or more vessels was observed in 30.6% of patients with SYSO and independently increased the risk of poor outcome (odds ratio, 2.76; 95% confidence interval, 2.12-3.59). The severity of SYSO was associated with outcome and showed a significant dose-response trend (P<0.001). The effect of SYSO on outcome did not significantly differ by individual arterial location (P for contrast=0.21). Conclusions Approximately 60% of patients with acute ischemic stroke had SYSO, and the severity and number were inversely correlated with outcome. The results suggest that SYSO could predict stroke outcome.