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.

Background: Delayed arrival at hospital is one of the major obstacles in enhancing the rate of thrombolysis therapy in patients with acute ischemic stroke. Our study aimed to investigate factors associated with prehospital delay after acute ischemic stroke in Korea. Methods: A prospective, multicenter study was conducted at 14 tertiary hospitals in Korea from March 2009 to July 2009. We interviewed 500 consecutive patients with acute ischemic stroke who arrived within 48 hours. Univariate and multivariate analyses were performed to evaluate factors influencing prehospital delay. Results: Among the 500 patients (median 67 years, 62% men), the median time interval from symptom onset to arrival was 474 minutes (interquartile range, 170-1313). Early arrival within 3 hours of symptom onset was significantly associated with the following factors: high National Institutes of Health Stroke Scale (NIHSS) score, previous stroke, atrial fibrillation, use of ambulance, knowledge about thrombolysis and awareness of the patient/bystander that the initial symptom was a stroke. Multivariable logistic regression analysis indicated that awareness of the patient/bystander that the initial symptom was a stroke (OR 4.438, 95% CI 2.669-7.381), knowledge about thrombolysis (OR 2.002, 95% CI 1.104-3.633) and use of ambulance (OR 1.961, 95% CI 1.176-3.270) were significantly associated with early arrival. Conclusions: In Korea, stroke awareness not only on the part of patients, but also of bystanders, had a great impact on early arrival at hospital. To increase the rate of thrombolysis therapy and the incidence of favorable outcomes, extensive general public education including how to recognize stroke symptoms would be important.

Background: Preclinical data suggest circadian variation in ischemic stroke progression, with more active cell death and infarct growth in rodent models with inactive phase (daytime) than active phase (nighttime) stroke onset. We aimed to examine the association of stroke onset time with presenting severity, early neurological deterioration (END), and long-term functional outcome in human ischemic stroke.Methods and findings: In a Korean nationwide multicenter observational cohort study from May 2011 to July 2020, we assessed circadian effects on initial stroke severity (National Institutes of Health Stroke Scale [NIHSS] score at admission), END, and favorable functional outcome (3-month modified Rankin Scale [mRS] score 0 to 2 versus 3 to 6). We included 17,461 consecutive patients with witnessed ischemic stroke within 6 hours of onset. Stroke onset time was divided into 2 groups (day-onset [06:00 to 18:00] versus night-onset [18:00 to 06:00]) and into 6 groups by 4-hour intervals. We used mixed-effects ordered or logistic regression models while accounting for clustering by hospitals. Mean age was 66.9 (SD 13.4) years, and 6,900 (39.5%) were women. END occurred in 2,219 (12.7%) patients. After adjusting for covariates including age, sex, previous stroke, prestroke mRS score, admission NIHSS score, hypertension, diabetes, hyperlipidemia, smoking, atrial fibrillation, prestroke antiplatelet use, prestroke statin use, revascularization, season of stroke onset, and time from onset to hospital arrival, night-onset stroke was more prone to END (adjusted incidence 14.4% versus 12.8%,p= 0.006) and had a lower likelihood of favorable outcome (adjusted odds ratio, 0.88 [95% CI, 0.79 to 0.98];p= 0.03) compared with day-onset stroke. When stroke onset times were grouped by 4-hour intervals, a monotonic gradient in presenting NIHSS score was noted, rising from a nadir in 06:00 to 10:00 to a peak in 02:00 to 06:00. The 18:00 to 22:00 and 22:00 to 02:00 onset stroke patients were more likely to experience END than the 06:00 to 10:00 onset stroke patients. At 3 months, there was a monotonic gradient in the rate of favorable functional outcome, falling from a peak at 06:00 to 10:00 to a nadir at 22:00 to 02:00. Study limitations include the lack of information on sleep disorders and patient work/activity schedules.Conclusions: Night-onset strokes, compared with day-onset strokes, are associated with higher presenting neurologic severity, more frequent END, and worse 3-month functional outcome. These findings suggest that circadian time of onset is an important additional variable for inclusion in epidemiologic natural history studies and in treatment trials of neuroprotective and reperfusion agents for acute ischemic stroke.

Background—: A dynamic change in industry, lifestyle, and healthcare structure brings a corresponding change in disease patterns. Limited data exist with respect to secular trends in stroke epidemiology in Korea, a rapidly developed country. Methods and Results—: We analyzed individual patient data registered the Korean Stroke Registry, a nationwide hospital-based stroke database, between January 2002 and November 2010. Mortality data were obtained from a national death certificate system. Linear or logistic regression analyses were performed to assess secular trends. A total of 46 098 patients were included in this study. Mean±SD age was 66.1±12.3 years, and 57.6% of the patients were men. Over the 9-year period, patient ages steadily increased by 0.24 year annually ( P <0.001). Risk factor proportions of hypertension, diabetes, smoking, and prior stroke declined slightly ( P <0.05 for all). However, dyslipidemia frequency showed a complex pattern of an initial decline and then an increase. For relative proportions of subtypes, cardioembolism increased, small vessel occlusion decreased, and large artery atherosclerosis remained stable. Still, intracranial stenosis overwhelms extracranial stenosis, but extracranial stenosis is on the rise. Arrival within 3 hours increased from 20% to 29%, and reperfusion therapy increased from 5.3% to 7.0%. Age-adjusted all-cause mortality did not decrease at 30 days but decreased at 1 year over time. Conclusions—: During the first decade of 21st century, stroke characteristics in Korea changed, likely because of increased lifespan, westernized lifestyle, and improved public awareness. Stroke experts need to cope with these distinguishing trends to establish a better strategy for prevention and acute therapy.

Futile reperfusion (poor functional status despite successful reperfusion) was observed in up to 67% of patients enrolled in recent endovascular treatment (EVT) clinical trials. We investigated the impact of baseline stroke severity on both futile reperfusion and therapeutic benefit of successful EVT. Using a prospective multicenter stroke registry, we identified consecutive ischemic stroke patients with anterior circulation large artery occlusion, who were reperfused successfully by EVT (Thrombolysis in Cerebral Infarction grade 2b–3). The rate of futile reperfusion was assessed across the initial National Institutes of Health Stroke Scale (NIHSS) scores. The frequency of poor outcomes (modified Rankin scale [mRS] 3–6) according to NIHSS scores was compared between patients revascularized successfully by EVT and those who did not receive EVT, after standardizing for age. Among 21,591 patients with ischemic stroke, 972 (4.5%) received EVT within 12 h of onset, including 440 who met study eligibility criteria. Futile reperfusion was observed in 226 of the 440 study-eligible patients (51.4%) and was associated with stroke severity: 20.9% in NIHSS scores ≤5, 34.6% in 6–10, 58.9% in 11–20, and 63.8% in > 20 (p < 0.001). Nonetheless, the therapeutic benefit of EVT also increased with increasing stroke severity (p for interaction < 0.001): 0.1% in NIHSS ≤5, 18.6% in 6–10, 28.7% in 11–20, and 34.3% in > 20. EVT is more beneficial with increasing stroke severity, although futile reperfusion also increases with higher stroke severity.

Background: It is not yet clear whether nutritional status is associated with post-stroke cognitive impairment (PSCI). We examined the geriatric nutritional risk index (GNRI) on the domain-specific cognitive outcomes 3 months after a stroke. Methods: A total of 344 patients with acute ischemic stroke were included for the analysis. The GNRI was calculated as 1.489 × serum albumin (g/L) + 41.7 × admission weight (kg)/ideal body weight (kg) and was dichotomized according to the prespecified cut-off points for no risk and any risks. The primary outcome was PSCI, defined as having adjusted z-scores of less than −2 standard deviations in at least one cognitive domain: executive/activation, memory, visuospatial and language. Multiple logistic regression and linear regression analyses were performed to investigate the association between the GNRI and cognitive outcomes. Results: Seventy (20.3%) patients developed PSCI 3 months after a stroke. The mean GNRI was 106.1 ± 8.6, and 59 (17.2%) patients had low (<98) GNRI scores. A low GNRI was independently associated with the PSCI after adjusting for age, sex, education, initial stroke severity, stroke mechanism and left hemispheric lesion (odds ratio, 2.04; 95% confidence interval, 1.00–4.14). The GNRI scores were also significantly associated with the z-scores from the mini-mental status examination and the frontal domain (β = 0.04, p-value = 0.03; β = 0.03, p-value = 0.03, respectively). Conclusions: A low GNRI was independently associated with the development of PSCI at 3 months after an ischemic stroke. The GNRI scores were specifically associated with the z-scores of the global cognition and frontal domain cognitive outcomes.