Non-invasive brain stimulation effectively improves post-stroke sensory impairment: a systematic review and meta-analysis.

More than half of stroke patients experience sensory dysfunction that affects their quality of life. Previous training modalities are ineffective in improving sensory function. In contrast, non-invasive brain stimulation (NIBS) is a new promising intervention for stroke rehabilitation. The aim of this meta-analysis was to summarize the current effectiveness of NIBS in the treatment of post-stroke sensory dysfunction. Articles published in PubMed, Web of Science, Embase, China National Knowledge Infrastructure (CNKI), Chinese scientific journals full-text database (VIP), and Wanfang database from the inception to March 8, 2023 were searched. There were no restrictions on language. A total of 14 RCTs were included (combined n = 804). Moderate-quality evidence suggested that NIBS significantly improved sensory function after stroke, and significant effects were observed up to 1 year after the intervention. In subgroup analysis, treatment with transcranial direct current stimulation (tDCS) or repetitive transcranial magnetic stimulation (rTMS) was significantly more effective than controls for recovery of sensory function in stroke patients. Stimulation of the primary motor cortex (M1), primary somatosensory cortex (S1) or M1 + S1 stimulation sites significantly improved sensory function. NIBS for sensory dysfunction showed significant therapeutic potential in patients with different stages of stroke. No significant effects were observed in subjects with less than 10 NIBS stimulations. Significant therapeutic effects were observed with either high-frequency or low-frequency rTMS.

Disparities in transitions of acute stroke care: The transitions of care stroke disparities study methodological report.

OBJECTIVE: The Transitions of Stroke Care Disparities Study (TCSD-S) is an observational study designed to determine race-ethnic and sex disparities in post-hospital discharge transitions of stroke care and stroke outcomes and to develop hospital-level initiatives to reduce these disparities to improve stroke outcomes. MATERIALS AND METHODS: Here, we present the study rationale, describe the methodology, report preliminary outcomes, and discuss a critical need for the development, implementation, and dissemination of interventions for successful post-hospital transition of stroke care. The preliminary outcomes describe the demographic, stroke risk factor, socioeconomic, and acute care characteristics of eligible participants by race-ethnicity and sex. We also report on all-cause and vascular-related death, readmissions, and hospital/emergency room representations at 30- and 90-days after hospital discharge. RESULTS: The preliminary sample included data from 1048 ischemic stroke and intracerebral hemorrhage discharged from 10 comprehensive stroke centers across the state of Florida. The overall sample was 45% female, 22% Non-Hispanic Black and 21% Hispanic participants, with an average age of 64 ± 14 years. All cause death, readmissions, or hospital/emergency room representations are 10% and 19% at 30 and 90 days, respectively. One in 5 outcomes was vascular-related. CONCLUSIONS: This study highlights the transition from stroke hospitalization as an area in need for considerable improvement in systems of care for stroke patients discharged from hospital. Results from our preliminary analysis highlight the importance of investigating race-ethnic and sex differences in post-stroke outcomes.

Impact of Hypertensive Disorders of Pregnancy on the Risk of Stroke Stratified by Subtypes and Follow-Up Time.

BACKGROUND AND PURPOSE: Hypertensive disorders of pregnancy (HDP) comprise 4 subtypes. Previous studies have not investigated the relationship between stroke risk, different HDP subtypes, and follow-up time, which was the purpose of this study. METHODS: Data of 17 588 women aged 18 to 45 years who had a history of HDP in Taiwan from 2000 to 2017 was retrospectively reviewed. After matching with confounders, 13 617 HDP women and 54 468 non-HDP women were recruited. RESULTS: HDP women had an adjusted hazard ratio (aHR) of 1.71 (95% CI, 1.46-2.00) for stroke, and 1.60 (1.35-1.89) and 2.98 (2.13-4.18) for ischemic and hemorrhagic stroke, respectively (P<0.001 for all). The overall stroke risk in the HDP group was still 2.04 times 10 to 15 years after childbirth (1.47-2.83, P<0.001). Although the risks of both ischemic and hemorrhagic stroke persisted, their risk time trends were different. The risk of ischemic stroke reached peak during 1 to 3 years after childbirth with an aHR of 2.14 (1.36-3.38), while hemorrhagic stroke risk gradually increased and had an aHR of 4.64 (2.47-8.73) after 10 to 15 years of childbirth (both P<0.001). Among the 4 HDP subtypes, chronic hypertension with superimposed preeclampsia had the highest stroke risk (aHR=3.86, 1.91-7.82, P<0.001), followed by preeclampsia-eclampsia (aHR=2.00, 1.63-2.45, P<0.001), and gestational hypertension (aHR=1.68, 1.13-2.52, P<0.05); chronic preexisting hypertension had the lowest stroke risk (aHR=1.27, 0.97-1.68, P>0.05). Furthermore, multiple HDP combined with preeclampsia had aHR of 5.48 (1.14-26.42, P<0.05). CONCLUSIONS: The effect of HDP on the risk of future stroke persisted for up to 17 years, both for ischemic and hemorrhagic strokes. The presence of multiple HDP and preeclampsia further increase the stroke risk.

Classification of Stroke Patients With Dysphagia Into Subgroups Based on Patterns of Submental Muscle Strength and Skill Impairment.

OBJECTIVES: To identify and characterize subgroups of stroke patients with clinical signs of dysphagia, based on swallowing-related strength and skill impairments of the submental muscle group. DESIGN: Prospective observational study. SETTING: Inpatient rehabilitation centers and community dwellings. PARTICIPANTS: Individuals (N=114), including stroke patients with dysphagia (n=55) and 2 control groups including myopathic patients with dysphagia (n=19) and healthy volunteers (n=40) were included in this study. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: Novel clinical assessment of strength (force generation) and skill (spatial and temporal precision of muscle activation) of the submental muscle group during swallowing and nonswallowing behaviors, using surface electromyography and dynamometry. RESULTS: Hierarchical cluster analysis revealed 4 clusters, which could be broadly characterized as cluster 1: intact strength and skill, cluster 2: poor strength and poor nonswallowing skill, cluster 3: poor strength, and cluster 4: poor strength and poor swallowing skill. Membership in cluster was significantly associated with medical diagnosis (P<.001). The majority of healthy and myopathic participants were assigned to clusters 1 and 3, respectively, whereas stroke patients were found in all 4 clusters. Skill outcome measures were more predictive of cluster assignment than strength measures. CONCLUSIONS: Although healthy and myopathic participants demonstrated predominantly homogeneous swallowing patterns of submental muscle function within their etiology, several subgroups were identified within stroke, possibly reflecting different subtypes of swallowing function. Future research should focus on the nature and rehabilitation needs of these subtypes. Assessment of skill in swallowing may be an important but overlooked aspect of rehabilitation.

ADL Outcome of Stroke by Stroke Type and Time from Onset to Admission to a Comprehensive Inpatient Rehabilitation Ward.

OBJECTIVE: To examine the effect of onset to admission interval (OAI) and stroke type on activities of daily living (ADL) outcome. MATERIALS AND METHODS: Stroke patients (n=3112) admitted to and discharged from comprehensive inpatient rehabilitation wards at Nanakuri Memorial Hospital were classified into 8 OAI segments and by stroke type [intracerebral hemorrhage (ICH) and cerebral infarction (CI)]. Motor subscore of the Functional Independence Measure (FIM-M) on admission, FIM-M at discharge, FIM-M gain, length of stay (LOS), and FIM-M efficiency in the ICH and CI group matched by OAI segment were compared using the Wilcoxon test. Multiple comparisons using the Steel-Dwass test of FIM-M on admission, FIM-M at discharge, FIM-M gain, LOS, and FIM-M efficiency by OAI segments were performed. RESULTS: FIM-M on admission was lower in the ICH group than the CI group in matched OAI segments. However, FIM-M improvement was greater in the ICH group than the CI group, resulting in no difference in FIM-M between groups at discharge. In both groups, the longer the OAI, the lower the FIM-M on admission and at discharge. The distribution pattern of significant differences among OAI segments differed between the groups. LOS tended to be longer and FIM-M efficiency tended to be higher in the ICH group than in the CI group. CONCLUSIONS: The brain mass effect at the time of admission was larger and took longer to decrease in the ICH group than in the CI group. These results may improve prediction of outcomes in comprehensive inpatient rehabilitation wards.

Etiological Subtypes of Transient Ischemic Attack and Ischemic Stroke in Chronic Kidney Disease: Population-Based Study.

BACKGROUND AND PURPOSE: Chronic kidney disease (CKD) is strongly associated with stroke risk, but the mechanisms underlying this association are unclear and might be informed by subtype-specific analyses. However, few studies have reported stroke subtypes in CKD according to established classification systems, such as the TOAST (Trial of ORG 10172 in Acute Stroke Treatment) criteria. We, therefore, aimed to determine which transient ischemic attack and ischemic stroke subtypes using the TOAST classification occur most frequently in patients with CKD. METHODS: In a population-based study of all transient ischemic attack and stroke (OXVASC [Oxford Vascular Study]; 2002-2017), all ischemic events were classified by TOAST subtypes (cardioembolism, large artery disease, small vessel disease, undetermined, multiple, other etiology, or incompletely investigated). Logistic regression was used to determine the relationship between CKD (defined as an estimated glomerular filtration rate <60 mL/min per 1.73 m2) and transient ischemic attack/stroke subtypes adjusted for age, sex, and hypertension and then stratified by age and estimated glomerular filtration rate category. RESULTS: Among 3178 patients with transient ischemic attack (n=1167), ischemic stroke (n=1802), and intracerebral hemorrhage (n=209), 1267 (40%) had CKD. Although there was a greater prevalence of cardioembolic events (31.8% versus 21.2%; P<0.001) in patients with CKD, this association was lost after adjustment for age, sex, and hypertension (adjusted odds ratio=1.20 [95% CI, 0.99-1.45]; P=0.07). Similarly, although patients with CKD had a lower prevalence of small vessel disease (8.8% versus 13.6%; P<0.001), undetermined (26.1% versus 39.4%; P<0.001), and other etiology (1.0% versus 3.6%; P<0.001) subtypes, these associations were also lost after adjustment (adjusted odds ratio=0.86 [0.65-1.13]; P=0.27 and 0.73 [0.36-1.43]; P=0.37 for small vessel disease and other defined etiology, respectively) for all but undetermined (adjusted odds ratio=0.81 [0.67-0.98]; P=0.03). CONCLUSIONS: There were no independent positive associations between CKD and specific TOAST subtypes, which suggest that renal-specific risk factors are unlikely to play an important role in the etiology of particular subtypes. Future studies of stroke and CKD should report subtype-specific analyses to gain further insights into potential mechanisms.

Reclassification of Ischemic Stroke Etiological Subtypes on the Basis of High-Risk Nonstenosing Carotid Plaque.

Background and Purpose- Carotid artery plaque with <50% luminal stenosis may be an underappreciated stroke mechanism. We assessed how many stroke causes might be reclassified after accounting for nonstenosing plaques with high-risk features. Methods- We included patients enrolled in the Cornell Acute Stroke Academic Registry from 2011 to 2015 who had anterior circulation infarction, magnetic resonance imaging of the brain, and magnetic resonance angiography of the neck. High-risk plaque was identified by intraplaque hemorrhage ascertained from routine neck magnetic resonance angiography studies using validated methods. Infarct location was determined from diffusion-weighted imaging. Intraplaque hemorrhage and infarct location were assessed separately in a blinded fashion by a neuroradiologist. We used the McNemar test for matched data to compare the prevalence of intraplaque hemorrhage ipsilateral versus contralateral to brain infarction. We reclassified stroke subtypes by including large-artery atherosclerosis as a cause if there was intraplaque hemorrhage ipsilateral to brain infarction, regardless of the degree of stenosis. Results- Among the 1721 acute ischemic stroke patients registered in the Cornell Acute Stroke Academic Registry from 2011 to 2015, 579 were eligible for this analysis. High-risk plaque was more common ipsilateral versus contralateral to brain infarction in large-artery atherosclerotic (risk ratio [RR], 3.7 [95% CI, 2.2-6.1]), cryptogenic (RR, 2.1 [95% CI, 1.4-3.1]), and cardioembolic strokes (RR, 1.7 [95% CI, 1.1-2.4]). There were nonsignificant ipsilateral-contralateral differences in high-risk plaque among lacunar strokes (RR, 1.2 [95% CI, 0.4-3.5]) and strokes of other determined cause (RR, 1.5 [95% CI, 0.7-3.3]). After accounting for ipsilateral high-risk plaque, 88 (15.2%) patients were reclassified: 38 (22.6%) cardioembolic to multiple potential etiologies, 6 (8.5%) lacunar to multiple, 3 (15.8%) other determined cause to multiple, and 41 (20.8%) cryptogenic to large-artery atherosclerosis. Conclusions- High-risk carotid plaque was more prevalent ipsilateral to brain infarction across several ischemic stroke subtypes. Accounting for such plaques may reclassify the etiologies of up to 15% of cases in our sample.

Two-Year Outcome after Endovascular Treatment for Acute Ischemic Stroke.

BACKGROUND: Several trials involving patients with acute ischemic stroke have shown better functional outcomes with endovascular treatment than with conventional treatment at 90 days after initiation of treatment. However, results on long-term clinical outcomes are lacking. METHODS: We assessed clinical outcomes 2 years after patients were randomly assigned to receive either endovascular treatment (intervention group) or conventional treatment (control group) for acute ischemic stroke. The primary outcome was the score on the modified Rankin scale at 2 years; this scale measures functional outcome, with scores ranging from 0 (no symptoms) to 6 (death). Secondary outcomes included all-cause mortality and the quality of life at 2 years, as measured by means of a health utility index that is based on the European Quality of Life-5 Dimensions questionnaire (scores range from -0.329 to 1, with higher scores indicating better health). RESULTS: Of the 500 patients who underwent randomization in the original trial, 2-year data for this extended follow-up trial were available for 391 patients (78.2%) and information on death was available for 459 patients (91.8%). The distribution of outcomes on the modified Rankin scale favored endovascular treatment over conventional treatment (adjusted common odds ratio, 1.68; 95% confidence interval [CI], 1.15 to 2.45; P=0.007). There was no significant difference between the treatment groups in the percentage of patients who had an excellent outcome (i.e., a modified Rankin scale score of 0 or 1). The mean quality-of-life score was 0.48 among patients randomly assigned to endovascular treatment as compared with 0.38 among patients randomly assigned to conventional treatment (mean difference, 0.10; 95% CI, 0.03 to 0.16; P=0.006). The cumulative 2-year mortality rate was 26.0% in the intervention group and 31.0% in the control group (adjusted hazard ratio, 0.9; 95% CI, 0.6 to 1.2; P=0.46). CONCLUSIONS: In this extended follow-up trial, the beneficial effect of endovascular treatment on functional outcome at 2 years in patients with acute ischemic stroke was similar to that reported at 90 days in the original trial. (Funded by the Netherlands Organization for Health Research and Development and others; MR CLEAN Current Controlled Trials number, ISRCTN10888758 , and Netherlands Trial Register number, NTR1804 , and MR CLEAN extended follow-up trial Netherlands Trial Register number, NTR5073 .).

Pathophysiology, classification, and MRI parallels in microvascular disease of the heart and brain.

Diagnostic imaging technology in vascular disease has long focused on large vessels and the pathologic processes that impact them. With improved diagnostic techniques, investigators are now able to uncover many underlying mechanisms and prognostic factors for microvascular disease. In the heart and brain, these pathologic entities include coronary microvascular disease and cerebral small vessel disease, both of which have significant impact on patients, causing angina, myocardial infarction, heart failure, stroke, and dementia. In the current paper, we will discuss parallels in pathophysiology, classification, and diagnostic modalities, with a focus on the role of magnetic resonance imaging in microvascular disease of the heart and brain. Novel approaches for streamlined imaging of the cardiac and central nervous systems including the use of intravascular contrast agents such as ferumoxytol are presented, and unmet research gaps in diagnostics are summarized.

CT Angiography for Triage of Patients with Acute Minor Stroke: A Cost-effectiveness Analysis.

Background Minor stroke is common and may represent up to two-thirds of cases of acute ischemic stroke. The cost-effectiveness of CT angiography in patients with minor stroke (National Institutes of Health Stroke Scale [NIHSS] score ≤6) is not well established. Purpose To evaluate cost-effectiveness of CT angiography in the detection of large-vessel occlusion (LVO) in patients with acute minor stroke (NIHSS score ≤6). Materials and Methods A Markov decision-analytic model with a societal perspective was constructed. Three different management strategies were evaluated: (a) no vascular imaging and best medical management, (b) CT angiography for all patients and immediate thrombectomy for LVO after intravenous thrombolysis, and (c) CT angiography for all and best medical management (including intravenous thrombolysis, with rescue thrombectomy for patients with LVO and neurologic deterioration). One-way, two-way, and probabilistic sensitivity analyses were performed. Results Base-case calculation showed that CT angiography followed by immediate thrombectomy had the lowest cost ($346 007) and highest health benefits (9.26 quality-adjusted life-years [QALYs]). CT angiography followed by best medical management with possible rescue thrombectomy for patients with LVO had a slightly higher cost ($346 500) and lower health benefits (9.09 QALYs). No vascular imaging had the highest cost and lowest health benefits. The difference in health benefits compared with the CT angiography and immediate thrombectomy strategy was 0.39 QALY, which corresponds to 142 days in perfect health per patient. The conclusion was robust in a probabilistic sensitivity analysis. CT angiography was cost-effective when the probability of LVO was greater than 0.16% in patients with acute minor stroke. The net monetary benefit of performing CT angiography was higher in younger patients ($68 950 difference between CT angiography followed by immediate thrombectomy and no vascular imaging in 55-year-old patients compared with $20 931 in 85-year-old patients). Conclusion Screening for large-vessel occlusion with CT angiography in patients with acute minor stroke is cost-effective and associated with improved health outcomes. Undetected large-vessel occlusion in the absence of vascular imaging results in worse health outcomes and higher costs. © RSNA, 2020 Online supplemental material is available for this article.

Validation of the pediatric stroke outcome measure for classifying overall neurological deficit.

BACKGROUND: The pediatric stroke outcome measure (PSOM) is a standardized, disease-specific outcome measure. We aimed to validate the overall classification of neurological deficit severity using PSOM. METHODS: We identified 367 neonates/children with arterial ischemic stroke (AIS) (Derivation Cohort). We analyzed the PSOM subscales (scored as 0 [no deficit], 0.5 [minimal/mild deficit; normal function], 1 [moderate deficit; slowing function], or 2 [severe deficit; missing function]) to derive severity levels using latent class analysis (LCA). We validated a severity classification scheme (PSOM-SCS) in: (a) children who had Pediatric Evaluation of Disability Inventory (PEDI; n = 63) and/or the Pediatric Quality-of-Life Inventory (PedsQL; n = 97) scored; and (b) an external cohort (AIS; n = 102) with concurrently scored modified Rankin Scale (mRS), King's Outcome Scale for Childhood Head-Injury (KOSCHI) and PSOM. RESULTS: Within the Derivation Cohort, LCA identified three severity levels: "normal/mild," "moderate," and "severe" (83.7%, 13.3%, and 3%, respectively). We developed severity classification based on PSOM subscale scores: "normal/mild"-normal function in all domains or slowing in one domain, "moderate"-slowing in ≥2 domains or missing function in one domain, and "severe"-missing function in ≥2 domains or slowing in ≥1 plus missing in one domain. PEDI and PedsQL both differed significantly across the severity groups. PSOM-SCS displayed high concordance with mRS (agreement coefficient [AC2] = 0.88) and KOSCHI (AC2 = 0.79). CONCLUSION: The PSOM-SCS constitutes a valid tool for classifying overall neurological severity emphasizing function and encompassing the full range of severity in pediatric stroke. IMPACT: Arithmetic summing of the PSOM subscales scores to assess severity classification is inadequate.The prior severity classification using PSOM overestimates poor outcomes.Three distinct severity profiles using PSOM subscales are identified.The PSOM-SCS is in moderate to excellent agreement with other disability measures.PSOM-SCS offers a valid tool for classifying the overall neurological deficit severity.

Low grade albuminuria as a risk factor for subtypes of stroke - the HUNT Study in Norway.

BACKGROUND AND PURPOSE: Albuminuria is a marker for endothelial dysfunction and knowledge on its association with stroke and stroke subtypes are limited. METHODS: Corresponding data from 7261 participants of the population-based HUNT2 study (1995-1997) was linked with hospital records, identified all patients registered and diagnosed with a first-time stroke. Each diagnosis was validated by reviewal of the medical record appertaining to the individual. We then applied Cox proportional hazard models to estimate the hazard ratios (HRs) for the association between albuminuria (measured as albumin-to-creatinine-ratio, ACR) and diagnosis of stroke and stroke subtypes. RESULTS: 703 (9.7%) participants developed a first ischemic stroke during a median follow-up of 15 years. Higher albuminuria was associated with a higher rate for ischemic stroke and the risk rose steadily with increasing ACR (15% increment per unit increase in ACR concentration in mg/mmol). In the fully adjusted model, the HR for all ischemic strokes was 1.56 (95% CI 1.24-1.95) for those with an ACR ≥3 mg/mmol compared to participants with an ACR < 1 mg/mmol. Overall, increasing ACR was associated with a higher risk of all ischemic stroke subtypes. This was seen to be strongest for lacunar stroke (HR 1.75, CI 1.12-2.72, p = 0.019), and also for stroke of undetermined etiology (HR 1.53, CI 1.11-2.11, p = 0.009) and those caused by atherosclerosis in the large arteries (HR 1.51, CI 0.78-2.94, p = 0.186) than for cardio-embolic stroke (HR 1.22, CI 0.64-2.3, p = 0.518). CONCLUSIONS: Albuminuria is an important risk factor, potentially already at low grade, for ischemic stroke especially for lacunar subtype. Measuring albuminuria is both cheap and readily available. This offers the opportunity to evaluate the risk for endothelial dysfunction and thus the subsequent risk for stroke and cerebral small vessel disease.

TOAST classification and risk factors of ischemic stroke in Lebanon.

OBJECTIVES: Ischemic stroke is a common cause of morbidity and mortality especially in the increasingly older population. The variability in ischemic stroke subtypes and its risk factors across different populations suggest that more effort is needed to describe the stroke characteristics in order to develop a more tailored management for each population. We aim to describe the demographic characteristics, risk factors, and subtype distribution of subjects with ischemic stroke in the Lebanese population. MATERIALS AND METHODS: We conducted a cross-sectional study based on chart review on patients with ischemic stroke/transient ischemic attack at the American University of Beirut Medical center between 2015 and 2017. RESULTS: A total of 284 cases were included with a mean age of 72 years, and 58% male gender. The most commonly identified risk factors were hypertension (77%), dyslipidemia (62%), and diabetes mellitus (42%), while atrial fibrillation was only found in 27% of cases. The cohort distribution according to TOAST classification was as follows: 15% large artery stroke, 31% cardioembolic stroke, 17% small artery stroke, 10% stroke of other determined causes, and 27% stroke of unknown cause. CONCLUSION: This is the first study to address ischemic stroke characteristics in Lebanon.

Inconsistent Classification of Mild Stroke and Implications on Health Services Delivery.

OBJECTIVE: To conduct a scoping review on classifications of mild stroke based on stroke severity assessments and/or clinical signs and symptoms reported in the literature. DATA SOURCES: Electronic searches of PubMed, PsycINFO (Ovid), and Cumulative Index to Nursing and Allied Health (CINAHL-EBSCO) databases included keyword combinations of mild stroke, minor stroke, mini stroke, mild cerebrovascular, minor cerebrovascular, transient ischemic attack, or TIA. STUDY SELECTION: Inclusion criteria were limited to articles published between January 2003 and February 2018. Inclusion criteria included studies (1) with a definition of either mild or minor stroke, (2) written in English, and (3) with participants aged 18 years and older. Animal studies, reviews, dissertations, blogs, editorials, commentaries, case reports, newsletters, drug trials, and presentation abstracts were excluded. DATA EXTRACTION: Five reviewers independently screened titles and abstracts for inclusion and exclusion criteria. Two reviewers independently screened each full-text article for eligibility. The 5 reviewers checked the quality of the included full-text articles for accuracy. Data were extracted by 2 reviewers and verified by a third reviewer. DATA SYNTHESIS: Sixty-two studies were included in the final review. Ten unique definitions of mild stroke using stroke severity assessments were discovered, and 10 different cutoff points were used. The National Institutes of Health Stroke Scale was the most widely used measure to classify stroke severity. Synthesis also revealed variations in classification of mild stroke across publication years, time since stroke, settings, and medical factors including imaging, medical indicators, and clinical signs and symptoms. CONCLUSIONS: Inconsistencies in the classification of mild stroke are evident with varying use of stroke severity assessments, measurement cutoff scores, imaging tools, and clinical or functional outcomes. Continued work is necessary to develop a consensus definition of mild stroke, which directly affects treatment receipt, referral for services, and health service delivery.

Automatic Grading of Stroke Symptoms for Rapid Assessment Using Optimized Machine Learning and 4-Limb Kinematics: Clinical Validation Study.

BACKGROUND: Subtle abnormal motor signs are indications of serious neurological diseases. Although neurological deficits require fast initiation of treatment in a restricted time, it is difficult for nonspecialists to detect and objectively assess the symptoms. In the clinical environment, diagnoses and decisions are based on clinical grading methods, including the National Institutes of Health Stroke Scale (NIHSS) score or the Medical Research Council (MRC) score, which have been used to measure motor weakness. Objective grading in various environments is necessitated for consistent agreement among patients, caregivers, paramedics, and medical staff to facilitate rapid diagnoses and dispatches to appropriate medical centers. OBJECTIVE: In this study, we aimed to develop an autonomous grading system for stroke patients. We investigated the feasibility of our new system to assess motor weakness and grade NIHSS and MRC scores of 4 limbs, similar to the clinical examinations performed by medical staff. METHODS: We implemented an automatic grading system composed of a measuring unit with wearable sensors and a grading unit with optimized machine learning. Inertial sensors were attached to measure subtle weaknesses caused by paralysis of upper and lower limbs. We collected 60 instances of data with kinematic features of motor disorders from neurological examination and demographic information of stroke patients with NIHSS 0 or 1 and MRC 7, 8, or 9 grades in a stroke unit. Training data with 240 instances were generated using a synthetic minority oversampling technique to complement the imbalanced number of data between classes and low number of training data. We trained 2 representative machine learning algorithms, an ensemble and a support vector machine (SVM), to implement auto-NIHSS and auto-MRC grading. The optimized algorithms performed a 5-fold cross-validation and were searched by Bayes optimization in 30 trials. The trained model was tested with the 60 original hold-out instances for performance evaluation in accuracy, sensitivity, specificity, and area under the receiver operating characteristics curve (AUC). RESULTS: The proposed system can grade NIHSS scores with an accuracy of 83.3% and an AUC of 0.912 using an optimized ensemble algorithm, and it can grade with an accuracy of 80.0% and an AUC of 0.860 using an optimized SVM algorithm. The auto-MRC grading achieved an accuracy of 76.7% and a mean AUC of 0.870 in SVM classification and an accuracy of 78.3% and a mean AUC of 0.877 in ensemble classification. CONCLUSIONS: The automatic grading system quantifies proximal weakness in real time and assesses symptoms through automatic grading. The pilot outcomes demonstrated the feasibility of remote monitoring of motor weakness caused by stroke. The system can facilitate consistent grading with instant assessment and expedite dispatches to appropriate hospitals and treatment initiation by sharing auto-MRC and auto-NIHSS scores between prehospital and hospital responses as an objective observation.

The Usefulness of Thin-section Iso-Voxel Diffusion Weighted Imaging for Stroke Subtype Classification: Case Series and Review.

BACKGROUND: Determining stroke subtypes on initial clinical evaluation is a prerequisite for the selection of appropriate initial treatment. Although diffusion-weighted imaging (DWI) is a powerful tool for detection of acute cerebral infarction, its diagnostic accuracy is not always sufficient particularly in the hyperacute phase. METHODS: Patients admitted within 2 weeks from the symptom onset with the diagnosis of acute ischemic strokes were analyzed with thin-section iso-voxel DWI, namely 3-dimension DWI (3D-DWI), to obtain axial, coronal, and sagittal sections in order to elucidate stroke characteristics. In this case series, we introduce the effectiveness of 3D-DWI. RESULTS: 3D-DWI uncovered stroke subtypes and distribution more precisely compared with conventional DWI. While previous studies indicated the utility of thin section DWI in detecting infratentrial infarctions, 3D-DWI is beneficial for the detection of not only infratentrial but also supratentorial lesions. Furthermore, since both 3D-DWI and magnetic resonance angiography (MRA) are multiplanar reconstruction images, the fusion image of 3D-DWI with MRA is available, enabling cross-reference of spatial cerebrovascular configuration and ischemic lesions. CONCLUSIONS: 3D-DWI is applicable to standard 1.5 T MRI by slight modification of data acquisition protocols, and becomes a key modality to solve the diagnostic puzzle of acute ischemic strokes.

Apolipoproteins B and A1 in Ischemic Stroke Subtypes.

INTRODUCTION: Elevated serum apolipoprotein B and the apolipoprotein B/A1 ratio have been associated with ischemic stroke and intracranial atherosclerotic disease. We sought to assess the relationship between serum levels of apolipoprotein B, apolipoprotein A1, and the apolipoprotein B/A1 ratio with ischemic stroke subtypes and large artery atherosclerosis location. MATERIALS AND METHODS: We evaluated serum apolipoprotein B and apolipoprotein A1 levels in consecutive, statin-naïve, adult ischemic stroke patients admitted to an academic medical center in southern India. We evaluated for differences in the mean serum levels of apolipoprotein B, apolipoprotein A1, and the apolipoprotein B/A1 ratio between patients with ischemic stroke attributed to intracranial atherosclerotic disease, extracranial atherosclerotic disease, small vessel disease, and cardioembolism. In secondary analysis, we assessed for differences in these serum apolipoproteins between patients with moderate-severe intracranial atherosclerotic disease and extracranial atherosclerotic disease, irrespective of ischemic stroke subtype. RESULTS: Among the 156 ischemic stroke patients enrolled in this study, there were no significant differences in serum levels of apolipoprotein B, apolipoprotein A1, and the apolipoprotein B/A1 ratio between patients with distinct ischemic stroke subtypes. No significant differences were found in serum levels of apolipoprotein B, A1 and the apolipoprotein B/A1 ratio between patients with moderate-severe intracranial atherosclerotic disease and moderate-severe extracranial atherosclerotic disease. DISCUSSION: Serum levels of apolipoprotein B and A1 did not differ between ischemic stroke subtypes. Additional studies are needed to validate our findings and to better understand the relationship between serum apolipoproteins and stroke.

Effects of personal characteristics, disease uncertainty and knowledge on family caregivers' preparedness of stroke survivors: a cross-sectional study.

Family caregivers play an important role in the rehabilitation of stroke survivors. The aims of this study were to describe preparedness, uncertainty, and knowledge regarding stroke in family caregivers of people who have undergone strokes and to investigate factors influencing preparedness. A total of 306 caregivers completed the questionnaires, including the Caregiver Preparedness Scale, the Mishel Uncertainty in Illness Scale, and Knowledge of Stroke. The result showed that the mean score of the family caregivers' preparedness was 14.42, the mean score of disease uncertainty was 75.62, and the mean score of stroke knowledge was 10.41. Caregiver preparedness was negatively correlated with disease uncertainty and positively correlated with knowledge. Multivariate stepwise regression analysis showed that educational background, profession, caregiving experience and uncertainty degree of the family caregivers, gender, and age of stroke survivor could predict 45.90% of the total variation in preparedness. The findings suggest that demographic characteristics of stroke survivor and family caregiver, as well as caregivers' disease uncertainty, enable predict the level of caregiver preparedness. Medical professionals should pay attention to providing personalized and targeted approaches to maximize caregivers' preparedness.

Stroke Mechanisms in Symptomatic Intracranial Atherosclerotic Disease: Classification and Clinical Implications.

Background and Purpose- In patients with symptomatic intracranial atherosclerotic stenosis, identifying the underlying stroke mechanisms may inform secondary prevention. We aimed to propose reproducible classification criteria for stroke mechanisms based on routine neuroimaging in symptomatic intracranial atherosclerotic stenosis and explore their clinical implications. Methods- We recruited patients with acute ischemic stroke attributed to 50% to 99% intracranial atherosclerotic stenosis in anterior circulation from 2 centers. Two investigators independently classified probable stroke mechanisms as parent artery atherosclerosis occluding penetrating artery, artery-to-artery embolism, hypoperfusion, and mixed mechanisms, with prespecified criteria based on infarct topography and magnetic resonance/computed tomography angiography. These stroke mechanisms were correlated with features of the patients at baseline and recurrent ischemic stroke in the same territory or relevant transient ischemic attack within 1 year. Results- Among 153 patients recruited, the most common stroke mechanisms were isolated hypoperfusion (35.3%) and mixed mechanism of artery-to-artery embolism and hypoperfusion (37.3%) that was associated with higher incidence of dyslipidemia (P=0.045) and hypertension (P=0.033) than patients with other stroke mechanisms. The proposed criteria showed substantial to excellent intrarater and interrater reproducibilities (κ, 0.791-0.908). Overall, 31 patients received interventional treatment of the diseased intracranial artery; 122 received medical treatment, among whom a mixed mechanism of artery-to-artery embolism and hypoperfusion at baseline was associated with higher risk of ischemic stroke in the same territory within 1 year (24.4% versus 7.8%; hazard ratio, 3.40; 95% CI, 1.25-9.20; log-rank P=0.010) than other mechanisms combined. Conclusions- Artery-to-artery embolism and hypoperfusion commonly coexist in ischemic stroke attributed to intracranial atherosclerotic stenosis, which may be associated with higher risk of stroke relapse.

Causal Effect of Lp(a) [Lipoprotein(a)] Level on Ischemic Stroke and Alzheimer Disease: A Mendelian Randomization Study.

Background and Purpose- Stroke and Alzheimer disease are 2 major causes of neurological disability in aged people and shared overlapping predictors. In recent prospective studies, high Lp(a) [lipoprotein(a)] level is associated with high risk of stroke but low risk of Alzheimer disease. Whether this reflects a causal association remains to be established. The aim of this study is to examine the causal associations of Lp(a) concentrations on ischemic stroke, ischemic stroke subtypes, and Alzheimer disease. Methods- We used 9 single-nucleotide polymorphisms associated with Lp(a) concentrations as instrumental variables. Summary-level data on ischemic stroke and its subtypes were obtained from the Multiancestry Genome-Wide Association Study of Stroke consortium with European individuals ≤446 696 individuals. Summary-level data on Alzheimer disease were obtained from the International Genomics of Alzheimer Project With European individuals ≤54 162 individuals. Two-sample Mendelian randomization (MR) estimates were calculated with inverse-variance weighted, penalized inverse-variance weighted, simple median, weighted median, and MR Pleiotropy Residual Sum and Outlier approaches, and MR-Egger regression was used to explore pleiotropy. Results- Genetically predicted 1-SD log-transformed increase in Lp(a) concentrations was associated with a substantial increase in risk of large artery stroke (odds ratio, 1.20; 95% CI, 1.11-1.30; P<0.001) and a reduce in risk of small vessel stroke (odds ratio, 0.92; 95% CI, 0.88-0.97; P=0.001) and Alzheimer disease (odds ratio, 0.94; 95% CI, 0.91-0.97; P<0.001) using inverse-variance weighted method. No significant association was observed for total ischemic stroke or cardioembolic stroke. MR-Egger indicated no evidence of pleiotropic bias. Results were broadly consistent in sensitivity analyses using penalized inverse-variance weighted, simple median, weighted median, and MR Pleiotropy Residual Sum and Outlier approaches accounting for potential genetic pleiotropy or outliers. Conclusions- This study provides evidence to support that high Lp(a) concentrations was causally associated with an increased risk of large artery stroke but a decreased risk of small vessel stroke and Alzheimer disease. The mechanism underlying the double-edged sword effect of Lp(a) concentrations on neurological system requires further investigation.