Byung Woo Yoon

Effects of aspirin plus extended-release dipyridamole versus clopidogrel and telmisartan on disability and cognitive function after recurrent stroke in patients with ischaemic stroke in the Prevention Regimen for Effectively Avoiding Second Strokes (PRoFESS) trial: a double-blind, active and placebo-controlled study

BACKGROUND The treatment of ischaemic stroke with neuroprotective drugs has been unsuccessful, and whether these compounds can be used to reduce disability after recurrent stroke is unknown. The putative neuroprotective effects of antiplatelet compounds and the angiotensin II receptor antagonist telmisartan were investigated in the Prevention Regimen for Effectively Avoiding Second Strokes (PRoFESS) trial. METHODS Patients who had had an ischaemic stroke were randomly assigned in a two by two factorial design to receive either 25 mg aspirin (ASA) and 200 mg extended-release dipyridamole (ER-DP) twice a day or 75 mg clopidogrel once a day, and either 80 mg telmisartan or placebo once per day. The predefined endpoints for this substudy were disability after a recurrent stroke, assessed with the modified Rankin scale (mRS) and Barthel index at 3 months, and cognitive function, assessed with the mini-mental state examination (MMSE) score at 4 weeks after randomisation and at the penultimate visit. Analysis was by intention to treat. The study was registered with ClinicalTrials.gov, number NCT00153062. FINDINGS 20,332 patients (mean age 66 years) were randomised and followed-up for a median of 2.4 years. Recurrent strokes occurred in 916 (9%) patients randomly assigned to ASA with ER-DP and 898 (9%) patients randomly assigned to clopidogrel; 880 (9%) patients randomly assigned to telmisartan and 934 (9%) patients given placebo had recurrent strokes. mRS scores were not statistically different in patients with recurrent stroke who were treated with ASA and ER-DP versus clopidogrel (p=0.38), or with telmisartan versus placebo (p=0.61). There was no significant difference in the proportion of patients with recurrent stroke with a good outcome, as measured with the Barthel index, across all treatment groups. Additionally, there was no significant difference in the median MMSE scores, the percentage of patients with an MMSE score of 24 points or less, the percentage of patients with a drop in MMSE score of 3 points or more between 1 month and the penultimate visit, and the number of patients with dementia among the treatment groups. There were no significant differences in the proportion of patients with cognitive impairment or dementia among the treatment groups. INTERPRETATION Disability due to recurrent stroke and cognitive decline in patients with ischaemic stroke were not different between the two antiplatelet regimens and were not affected by the preventive use of telmisartan.

Intensive blood-pressure lowering in patients with acute cerebral hemorrhage

BACKGROUND Limited data are available to guide the choice of a target for the systolic blood-pressure level when treating acute hypertensive response in patients with intracerebral hemorrhage. METHODS We randomly assigned eligible participants with intracerebral hemorrhage (volume, <60 cm(3)) and a Glasgow Coma Scale (GCS) score of 5 or more (on a scale from 3 to 15, with lower scores indicating worse condition) to a systolic blood-pressure target of 110 to 139 mm Hg (intensive treatment) or a target of 140 to 179 mm Hg (standard treatment) in order to test the superiority of intensive reduction of systolic blood pressure to standard reduction; intravenous nicardipine to lower blood pressure was administered within 4.5 hours after symptom onset. The primary outcome was death or disability (modified Rankin scale score of 4 to 6, on a scale ranging from 0 [no symptoms] to 6 [death]) at 3 months after randomization, as ascertained by an investigator who was unaware of the treatment assignments. RESULTS Among 1000 participants with a mean (±SD) systolic blood pressure of 200.6±27.0 mm Hg at baseline, 500 were assigned to intensive treatment and 500 to standard treatment. The mean age of the patients was 61.9 years, and 56.2% were Asian. Enrollment was stopped because of futility after a prespecified interim analysis. The primary outcome of death or disability was observed in 38.7% of the participants (186 of 481) in the intensive-treatment group and in 37.7% (181 of 480) in the standard-treatment group (relative risk, 1.04; 95% confidence interval, 0.85 to 1.27; analysis was adjusted for age, initial GCS score, and presence or absence of intraventricular hemorrhage). Serious adverse events occurring within 72 hours after randomization that were considered by the site investigator to be related to treatment were reported in 1.6% of the patients in the intensive-treatment group and in 1.2% of those in the standard-treatment group. The rate of renal adverse events within 7 days after randomization was significantly higher in the intensive-treatment group than in the standard-treatment group (9.0% vs. 4.0%, P=0.002). CONCLUSIONS The treatment of participants with intracerebral hemorrhage to achieve a target systolic blood pressure of 110 to 139 mm Hg did not result in a lower rate of death or disability than standard reduction to a target of 140 to 179 mm Hg. (Funded by the National Institute of Neurological Disorders and Stroke and the National Cerebral and Cardiovascular Center; ATACH-2 ClinicalTrials.gov number, NCT01176565 .).

Stroke Statistics in Korea: Part I. Epidemiology and Risk Factors: A Report from the Korean Stroke Society and Clinical Research Center for Stroke

The aim of the Part I of Stroke Statistics in Korea is to summarize nationally representative data of the epidemiology and risk factors of stroke in a single document. Every year, approximately 105,000 people experience a new or recurrent stroke and more than 26,000 die of stroke, which indicates that every 5 minutes stroke attacks someone and every 20 minutes stroke kills someone in Korea. Stroke accounts for roughly 1 of every 10 deaths. The estimated stroke prevalence is about 795,000 in people aged ≥30 years. The nationwide total cost for stroke care was 3,737 billion Korean won (US

Case Characteristics, Hyperacute Treatment, and Outcome Information from the Clinical Research Center for Stroke-Fifth Division Registry in South Korea

3.3 billion) in 2005. Fortunately, the annual stroke mortality rate decreased substantially by 28.3% during the first decade of the 21th century (53.2/100,000 in 2010). Among OECD countries, Korea had the lowest in-hospital 30-day case-fatality rate for ischemic stroke and ranked third lowest for hemorrhagic stroke in 2009. The proportion of ischemic stroke has steadily increased and accounted for 76% of all strokes in 2009. According to hospital registry studies, the 90-day mortality rate was 3-7% for ischemic stroke and 17% for intracerebral hemorrhage. For risk factors, among Korean adults ≥30 years of age, one in 3-4 has hypertension, one in 10 diabetes, and one in 7 hypercholesterolemia. One in 3 Korean adults ≥19 years of age is obese. Over the last 10 years, the prevalence of hypertension slightly decreased, but the prevalence of diabetes, hypercholesterolemia, and obesity increased. Smoking prevalence in men has decreased, but is still as high as 48%. This report could be a valuable resource for establishing health care policy and guiding future research directions.

Labeling efficacy of superparamagnetic iron oxide nanoparticles to human neural stem cells: comparison of ferumoxides, monocrystalline iron oxide, cross-linked iron oxide (CLIO)-NH2 and tat-CLIO.

Characteristics of stroke cases, acute stroke care, and outcomes after stroke differ according to geographical and cultural background. To provide epidemiological and clinical data on stroke care in South Korea, we analyzed a prospective multicenter clinical stroke registry, the Clinical Research Center for Stroke-Fifth Division (CRCS-5). Patients were 58% male with a mean age of 67.2±12.9 years and median National Institutes of Health Stroke Scale score of 3 [1-8] points. Over the 6 years of operation, temporal trends were documented including increasing utilization of recanalization treatment with shorter onset-to-arrival delay and decremental length of stay. Acute recanalization treatment was performed in 12.7% of cases with endovascular treatment utilized in 36%, but the proportion of endovascular recanalization varied across centers. Door-to-IV alteplase delay had a median of 45 [33-68] min. The rate of symptomatic hemorrhagic transformation (HT) was 7%, and that of any HT was 27% among recanalization-treated cases. Early neurological deterioration occurred in 15% of cases and were associated with longer length of stay and poorer 3-month outcomes. The proportion of mRS scores of 0-1 was 42% on discharge, 50% at 3 months, and 55% at 1 year after the index stroke. Recurrent stroke up to 1 year occurred in 4.5% of patients; the rate was higher among older individuals and those with neurologically severe deficits. The above findings will be compared with other Asian and US registry data in this article.

White matter lesions and poor outcome after intracerebral hemorrhage A nationwide cohort study

Objective We wanted to compare the human neural stem cell (hNSC) labeling efficacy of different superparamagnetic iron oxide nanoparticles (SPIONs), namely, ferumoxides, monocrystalline iron oxide (MION), cross-linked iron oxide (CLIO)-NH2 and tat-CLIO. Materials and Methods The hNSCs (5 × 105 HB1F3 cells/ml) were incubated for 24 hr in cell culture media that contained 25 µg/ml of ferumoxides, MION or CLIO-NH2, and with or without poly-L-lysine (PLL) and tat-CLIO. The cellular iron uptake was analyzed qualitatively with using a light microscope and this was quantified via atomic absorption spectrophotometry. The visibility of the labeled cells was assessed with MR imaging. Results The incorporation of SPIONs into the hNSCs did not affect the cellular proliferations and viabilities. The hNSCs labeled with tat-CLIO showed the longest retention, up to 72 hr, and they contained 2.15 ± 0.3 pg iron/cell, which are 59 fold, 430 fold and six fold more incorporated iron than that of the hNSCs labeled with ferumoxides, MION or CLIO-NH2, respectively. However, when PLL was added, the incorporation of ferumoxides, MION or CLIO-NH2 into the hNSCs was comparable to that of tat-CLIO. Conclusion For MR imaging, hNSCs can be efficiently labeled with tat-CLIO alone or with a combination of ferumoxides, MION, CLIO-NH2 and the transfection agent PLL.

Paradoxical longevity in obese patients with intracerebral hemorrhage

Background: The ability to predict poor outcome is important for patient care and treatment decision-making in cases of intracerebral hemorrhage (ICH). Previous studies have included relatively brief follow-up periods and small numbers of patients, and are limited in terms of considerations regarding individual brain vulnerabilities. Methods: The authors prospectively enrolled 1,321 ICH patients nationwide from 33 hospitals. Clinical, laboratory, and imaging variables, including white matter lesions (WMLs), were collected at admission. Immediate outcome after ICH was measured using total Glasgow Coma Scale (GCS) score at admission, early outcome using 30-day mortality, and long-term outcome using relative risk for mortality. The vital status of included patients was ascertained on December 31, 2006, using Korean National Death Certificates (mean follow-up, 32.6 months). Results: Of the 1,321 ICH patients included, 352 (27.8%) presented with a moderate GCS score (8.5–12.4) and 249 (19.7%) with a severe GCS score (≤8.4). The mortality rate was 9.1% at day 30 post-ICH and 381 patients (29.8%) had died up to the end of December 2006. Extensive WMLs were associated with severe GCS scores at admission (odds ratio [OR] 2.45, 95% confidence interval [CI] 1.73–3.46), 30-day mortality (OR 2.52, 95% CI 1.33–4.75), and the relative risk for mortality (RR 2.61, 95% CI 1.79–3.82) after adjusting for relevant covariates. Conclusions: These findings suggest that white matter lesions, which may reflect the vulnerability of individual brains to pathologic insults, should be considered when assessing immediate, early, and long-term outcomes after intracerebral hemorrhage.

Correlation of Coronary and Cerebral Atherosclerosis: Difference between Extracranial and Intracranial Arteries

Background: The paradoxical phenomenon of relative longevity among obese patients with established diseases has been reported for various disease conditions. The authors sought to investigate whether the obesity paradox also applies to intracerebral hemorrhage (ICH) survivors. Methods: A total of 1,604 patients with ICH from 33 centers with nationwide coverage were prospectively enrolled to this cohort between October 2002 and March 2004. Baseline information including body mass index (BMI) was collected at admission, and mortality status was ascertained from the governmental mortality archive on December 2006. Associations between obesity and 30-day mortality or long-term risk of death were analyzed. Results: Among the 1,356 patients with ICH included, the 30-day mortality rate was 7.2% and the long-term mortality rate was 26.9% after a mean follow-up of 33.6 ± 15.5 months. Neither BMI nor obesity status were associated with 30-day mortality after ICH. However, BMI was independently associated with a lower risk of long-term mortality (hazard ratio [HR] 0.91 per 1-kg/m2 increase; 95% confidence interval [CI] 0.87–0.95). As compared with patients of normal weight, underweight subjects had a higher risk of death (HR 1.64; 95% CI 1.11–2.40), and conversely, overweight (HR 0.69; 95% CI 0.49–0.96) or obese (HR 0.61; 95% CI 0.43–0.88) subjects showed a lower risk of post-ICH death. Conclusion: In our study, obesity was associated with a lower risk of long-term death but not with 30-day mortality after ICH. Thus, it may be considered that an obesity status in a patient with ICH be treated as an indication of metabolic reservoir capacity and an increased likelihood of survival.

Huntingtin is degraded to small fragments by calpain after ischemic injury

Background: A difference with regard to the correlation with coronary atherosclerosis (CAS) between extracranial carotid atherosclerosis (ECAS) and intracranial cerebral atherosclerosis (ICAS) has been assumed but not proven clearly by direct comparison within the same population. Methods: A consecutive series of 246 patients undergoing coronary artery bypass graft surgery were reviewed. The severity of CAS was estimated as a CAS score based on coronary angiography. The presence of ECAS and ICAS was screened by transcranial Doppler and carotid duplex sonography, and confirmed by magnetic resonance angiography. Results: The CAS scores in patients with ECAS were observed to be higher than those in patients without ECAS (10.62 ± 4.80 vs. 9.45 ± 4.25; p = 0.054 on the Mann-Whitney U test). The difference in CAS scores was smaller between patients with and without ICAS (10.41 ± 4.44 vs. 9.66 ± 4.49; p = 0.201). Similar patterns were observed on comparing the correlation of ECAS and ICAS with a quartile of the CAS score. An advanced CAS, which was generated by collapsing the quartiles of the CAS score into 75th percentile or less and more than the 75th percentile, was significantly associated with ECAS, but not with ICAS. These associations remained unchanged after adjustments had been made for age, sex, hypertension, diabetes mellitus, hyperlipidemia, smoking and a history of stroke or transient ischemic attack. Conclusions: This study suggests that the correlation of CAS with ECAS is stronger than that of CAS with ICAS, and this difference is independent of the classic risk factors for atherosclerosis.

Lithium pretreatment reduces brain injury after intracerebral hemorrhage in rats

The gene defect in Huntingtons disease (HD) causes a polyglutamine expansion in the N-terminal region of huntingtin (N-htt). In vitro studies suggest that mutant N-htt fragments can aggregate and cause cell death in HD. The physiological and pathological conditions that affect htt proteolysis in the brain are unclear. We examined htt expression by Western blot in the rat brain after transient ischemic injury, which causes striatal neurodegeneration similar to that seen in HD and activates proteases including calcium-dependent calpains. Focal brain ischemia reduced levels of full-length htt in the infarcted cortex and striatum and increased expression of a 55-kDa N-htt fragment that was also produced by treating control brain extracts with calpain. N-htt fragments between 65 and 80 kDa also rose after injury, but these fragments were not as long-lived as the 55-kDa N-htt fragment. The results suggest that after ischemic injury full-length htt is degraded in degenerating neurons and an N-htt fragment accumulates.