bluuebunny/crossref_metadata_2025 huggingface dataset:
Abstract TP443: Effects of Dabigatran in Mouse Models of Aging and Cerebral Amyloid Angiopathy
Authors: MIchael Neethu , Grigoryan Mher M , Kilday Kelley , Sumbria Rachita K , Vasilevko Vitaly , van Ryn Joanne , Cribbs David , Paganini-Hill Annlia , Fisher Mark
Published: January 2019

Background:
Oral anticoagulants are a critical component of stroke prevention, but carry a risk of brain hemorrhage. These hemorrhagic complications tend to occur in elderly individuals, especially those with predisposing conditions such as cerebral amyloid angiopathy. Clinical evidence suggests that newer oral anticoagulants (NOACs) are safer than traditional oral anticoagulants.

Objectives:
We analyzed whether the NOAC dabigatran produces cerebral microhemorrhage (the pathological substrate of MRI-demonstrable cerebral microbleeds) or intracerebral hemorrhage in aged mice with and without hemorrhage-predisposing angiopathy.

Methods:
We studied aged (22 months old) Tg2576 (a model of cerebral amyloid angiopathy) and wild-type (WT) littermate mice. Mice received either dabigatran etexilate (DE) (Tg N=7; WT N=10) or vehicle (Tg N=9; WT N=7) by gavage for four weeks. Anticoagulation effects of dabigatran were confirmed using diluted thrombin time assay.

Results:
No mice experienced intracerebral hemorrhage. Cerebral microhemorrhage analysis, performed using Prussian-blue and H&E staining, showed no significant change in either number or size of cerebral microhemorrhage in DE-treated animals. Analysis of biochemical parameters for endothelial activation (ICAM-1), blood-brain barrier disruption (IgG, claudin-5, fibrinogen), microglial activation (Iba-1) or astrocyte activation (GFAP) showed neither exacerbation nor protective effects of DE in either Tg2576 or WT mice.

Conclusion:
Our study provides histological and biochemical evidence that aged mice, with or without predisposing factors for brain hemorrhage, tolerate anticoagulation with dabigatran. Dabigatran did not induce intracerebral hemorrhage, and neither induced nor enlarged spontaneous cerebral microhemorrhage. These findings may provide some reassurance for the use of dabigatran in high-risk patient populations.
Abstract TP444: Liver Fibrosis is Associated With Hematoma Expansion and 90-Day Mortality in Primary Intracerebral Hemorrhage
Authors: Parikh Neal S , Kamel Hooman , Navi Babak B , Merkler Alexander E , Dawson Jesse , Elkind Mitchell S , Hanley Daniel F , Ziai Wendy C , Murthy Santosh B ,   On behalf of the VISTA-ICH Collaborators
Published: January 2019

Introduction:
Liver disease is associated with inflammation and coagulopathy. We hypothesized that liver fibrosis, a frequently subclinical precursor of cirrhosis, is associated with outcomes in intracerebral hemorrhage (ICH).

Methods:
We performed a retrospective cohort study using the Virtual International Stroke Trials Archive - ICH database. We included adult patients with primary ICH who presented within 24 hours of symptom onset. Patients with alcohol abuse and known liver disease were excluded. The exposure variables were three validated fibrosis indices calculated at the time of admission: the Aspartate aminotransferase Platelet Ratio Index (APRI), the Non-alcoholic Fatty Liver Disease Fibrosis Score (NFS), and the Fibrosis-4 (Fib-4) score. Our outcomes were hematoma expansion (HE) over 96 hours, perihematomal edema expansion, 90-day mortality, and 90-day disability (modified Rankin Scale scores 4-6). Multiple logistic regression models assessing the relationship between each 1.0 unit change in fibrosis indices and outcomes were adjusted for age, baseline ICH volume, Glasgow Coma Scale, location, intraventricular hemorrhage, and use of antithrombotic drugs. Patients with antithrombotic use and thrombocytopenia were excluded in sensitivity analyses.

Results:
Of 588 patients with ICH, mean age was 66 years (SD, 12), and mean baseline hematoma volume was 22.8 milliliters (SD, 21.6). Antithrombotic use was noted in 165 patients (28%). The mean APRI, NFS, and FIB-4 values were 0.4 (SD, 0.4), -0.8 (SD, 1.3), and 1.9 (SD, 1.4), respectively; the means reflect intermediate probabilities of fibrosis. HE was seen in 212 patients (36%). After adjusting, APRI was associated with HE (OR 2.00; 95% CI 1.09-3.67) and 90-day mortality (OR 1.75; 95% CI 1.04-2.97). NFS was also associated with HE (OR 1.20; 95% CI 1.04-1.46) and mortality (OR 1.34; 95% CI 1.02-1.75). Similarly, FIB-4 was associated with HE (OR 1.28; 95% CI 1.05-1.56) and mortality (OR 1.9; 95% CI 1.04-1.60). Indices were not associated with perihematomal edema expansion or 90-day disability. Sensitivity analysis results were similar.

Conclusion:
Liver fibrosis may be associated with HE and 90-day mortality after ICH. The implications of liver fibrosis for ICH warrant further investigation.
Abstract TP454: Decision Tree Model for Carotid Atherosclerotic Risks
Authors: Ahn Jeong-Ah
Published: January 2019

Background:
Carotid atherosclerosis is strongly associated with stroke risk. However, we do not know of the severity of the risk in carotid atherosclerosis patients before their ultrasonic evaluations.

Purposes:
The purpose of this study is to verify the risk factors that influence carotid atherosclerosis and develop a decision tree model.

Methods:
In this retrospective correlational and methodological study, all 509 adults (329 men and 180 women) who underwent carotid ultrasound at a hospital in Seoul, Korea, for 6 months were enrolled. Baseline data and the results of carotid ultrasound were collected from electronic medical records. Data analyses were performed with SPSS 23 software.

Results:
A decision tree model for carotid atherosclerotic risks with age, duration of diabetes and hypertension, and LDL values was developed. Various predictive prevalence rates according to 6 subgroups are presented in the model (Figure 1). Misclassification rate, sensitivity, specificity, and area under the curve of this model were 16.6%, 75.6%, 65.2%, and 0.77, respectively.

Conclusions:
We developed a decision tree model that may be useful for predicting the prevalence rate of carotid atherosclerosis according to individual patient risk factors. Furthermore, nursing management focus on patients in the high-risk group could help prevent stroke.
Abstract TP455: The Challenges and Successes of Mechanical Thrombectomy Implementation for Nurses in the United Kingdom
Authors: Cluckie Gillian , De Sousa Ismalia , Bailey Alastair
Published: January 2019

Introduction:
Mechanical thrombectomy is a newly developing clinical area in UK stroke care with commissioning and payment decisions made by the NHS during 2018. Stroke and neuroradiology nurses are crucial to the developing thrombectomy services and patient care. This paper reports the challenges and successes of thrombectomy nursing in the UK.

Method:
A National thrombectomy nurse forum was established in 2018 involving senior stroke and neuroradiology nurses from every neuroscience center. Data on service provision, challenges and successes were obtained via standardized online surveys prior to forum meetings and from workshops conducted during the fora.

Results:
84 delegates from 22 neuroscience centers attended forum meetings including England and all devolved Nations. Survey data confirmed that only 4 centers performed over 40 thrombectomies in the preceding year (range 0-145). Limitations to service provision were skilled interventional neuroradiologists and imaging capacity. 52% of respondents reported that nurses were involved in thrombectomy financial or service development. Only 33% of nurses reported working in a network with referral hospitals. Key challenges reported by nurses were staffing levels, training and education and post-thrombectomy nursing care. Successes in thrombectomy nursing were reported as joint working with neuroradiology nurses, thrombectomy competencies and education and protocol based post-procedure care.

Conclusion:
The development of mechanical thrombectomy services in the UK also requires nursing developments. Further work is needed Nationally to develop standardized thrombectomy education and competencies and to develop a National stroke nursing career structure.
Abstract TP463: Enhancing Access to Stroke Neurology Care for Patients With Sickle Cell Disease
Authors: Lara-Angulo Melissa , Molokie Robert , Testai Fernando D
Published: January 2019

Introduction:
Patients with chronic illness have demonstrated non-adherence rates to clinic appointments ranging between 20-40%, however, few studies have documented non-adherence rates in patients with sickle cell disease. One study estimated that during an 8-month period non-adherence rates were as high as 46%. Patients with sickle cell disease and a history of prior stroke are at particularly high risk of recurrence for secondary stroke requiring routine follow up. This study aimed at examining the effect on non-adherence rates after the development of a combined stroke-sickle cell outpatient clinic.

Methods:
Non-adherence rates were examined in the separate stroke clinic and compared to the combined outpatient stroke-sickle cell clinic, staffed by a vascular neurology physician, an advanced practice nurse (APN) and a hematology physician. The APN was readily available for consultation and follow-up of patients with a history of stroke, suspected stroke, or transient ischemic attack. Non-adherence rates were calculated based on no show events over total scheduled clinic events. Descriptive statistics were used to compare groups of patients and a Chi-Square was used to compare non adherence between groups.

Results:
Since September 2015 to August 2018, there was a total of 34 total scheduled clinic visits in the separate stroke clinic, resulting in a non-adherence rate of 26.5%. Since the inception of the combined stroke-sickle cell clinic in September 2016 to August 2018, there was a total of 45 scheduled clinic visits, resulting in a non-adherence rate of 11.1%. The number of new consultations for the stroke clinic and combined clinic were 44.1% and 40.0% respectively.

Conclusion:
The development of a combined stroke-sickle cell outpatient clinic may be an effective, multidisciplinary method for improving non-adherence rates in patients with sickle cell disease and a history of stroke. In addition, creating a combined clinic both increases patient access for both sickle cell patients at high risk for cerebrovascular disease as well as stroke patients without a history of sickle cell disease.
Abstract TP475: A Case of Suspected Vertebral Giant Cell Arteritis Causing Cervico-medullary Ischemia
Authors: Muzammil Syeda Maria , Farhat Husain , Singhal Divya
Published: January 2019

Objective:
To present a rare case of cervico-medullary ischemia suspected to be from giant cell arteritis (GCA).

Background:
In patients with GCA, vertebral artery involvement occurs in 3-4% of ischemic events and manifests by disturbances, cranial nerve palsies, cerebellar signs, weakness and altered consciousness (1,2).

Design:
Case Report.

Results:
A 79-year-old man presented with 2-week history of vertigo right-sided weakness, right-sided neck pain and occipital headaches with magnetic resonance imaging (MRI) brain and cervical spine without contrast showing right distal medulla and cervico-medullary junction infarct and magnetic resonance angiogram (MRA) neck showing bilaterally diminutive/atherosclerotic vertebral arteries with absence of flow in right vertebral C2 segment. Relevant tests showed an elevated white cell count of 14 K/mm
3
, C-reactive protein (CRP) of 171 mg/L, erythrocyte sedimentation rate (ESR) of 67 mm/hour, antinuclear antibodies (ANA) of 1: 1280 and unrevealing Reichlin profile, temporal artery ultrasound, carotid duplex, PET/CT and cerebrospinal fluid infectious workup. After initiation of Prednisolone 60 mg PO daily, patient reported improvement in pain and levels of inflammatory markers decreased. As patient was on Clopidogrel, temporal artery biopsy (TAB) was delayed and performed 14 days after initiation of steroids and showed no signs of inflammation. Patient is being planned for gradual steroid taper and monitoring of response.

Conclusion:
Vertebral GCA is a high fatality condition. A combination of persistently elevated inflammatory markers, unusual stroke location, bilateral vertebral artery disease with multiple areas of stenosis, improvement in weakness and pain after initiation of steroids were all highly suggestive of GCA vasculitic process. High index of suspicion is crucial as specific and curative treatment exists. In select cases where TAB is delayed, treatment should not be withheld.
Abstract TP479: Early Differential Expression of Chemotactic Genes in Peripheral Blood May Predict Poststroke Blood Brain Barrier Disruption
Authors: Barr Taura L , O'Connell Grant , Chantler Paul , Warach Steven
Published: January 2019

PhD Complications of endovascular thrombectomy limit its current utility to a subset of patients. Expanding the utility of mechanical thrombectomy is possible with the addition of blood biomarkers that could be used to identify patients who are at risk for complications related to reperfusion injury such as blood brain barrier (BBB) disruption and malignant edema. The objective of this pilot study was to identify an early pattern of gene expression in the peripheral immune system which could be used to predict post-stroke BBB disruption. Peripheral whole blood samples were obtained from acute ischemic stroke patients at emergency department admission, and BBB disruption was assessed via level of hyperintense reperfusion injury marker (HARM) on MRI at 24-hour follow-up. Microarray was used to transcriptionally profile admission blood samples, and a machine-learning technique known as genetic algorithm k-nearest neighbors (GA/kNN) was used to identify a pattern of gene expression which could optimally discriminate between patients who presented with mild HARM (n=8) and severe HARM (n=8) at follow-up imaging. GA/kNN identified ten genes (
LAIR2, IL8, CXCL5, RBP7, CCDC149, LY96, HPSE, DDIT4, E2F3,
and
ADAM15
) whose coordinate expression levels could discriminate between groups with 94% accuracy (88% sensitivity, 100% specificity). Furthermore, functional annotation enrichment analysis suggested that top genes identified by GA/kNN were enriched for genes involved in chemotaxis, suggesting that the early differential expression of genes associated with cellular migration may be predictive of post-stroke BBB disruption. The pattern of gene expression identified in this study shows strong potential for helping to guide selection of patients for mechanical thrombectomy, and warrants further evaluation to determine its true clinical efficacy.
Abstract TP485: Increasing Comfort With the National Institute of Health Stroke Scale Performance
Authors: Shoemake Anne
Published: January 2019

Background:
The online education used to teach the National Institute of Health Stroke Scale (NIHSS) throughout the hospital is a good foundation, but the lack of hands on experience and the inability to have a back and forth discussion regarding technique and scoring is a barrier to consistent and accurate scores.

Purpose:
To supplement online certification and increase comfort with NIHSS performance and scoring, we added a class that allows staff members to gain hands on experience and receive feedback before performing a NIHSS in a live setting.

Method:
Using a presentation created with the input of our neurologists and the National Institute of Health (NIH) guidelines, with groups of less than 8 newly certified nurses and paramedics, we discussed the NIHSS in-depth, focusing on assessing complicated patients and elements of the exam that are often challenging, such as ataxia and neglect. In pairs, attendees performed simulations of the NIHSS with one participant performing an assigned stroke patient scenario and the other administering the test in front of the class. We debriefed each case and identified any issues or concerns with scoring. A survey was provided after the class to determine the staff members’ perceived comfort with the scale.

Results:
All initial attendees (24) noted an improvement in comfort with the NIHSS. On a scale of 1-5, the initial average was 2.1 and the comfort level following the class was 4.2. The staff reported this was a helpful supplement to the existing education. Comments indicated that the simulations were particularly helpful.

Conclusion:
The addition of a supplemental NIHSS class was successful in increasing the comfort level of staff. Future classes will benefit from increased class length and more simulations.
Abstract TP486: Process and Practice: A Novel Stroke Program Partnership
Authors: Packard Laurel , Tubergen Tricia , Khan Muhib , Wills Nicole
Published: January 2019

Background:
Stroke program coordinators have, traditionally, been nurses. As nurses are integral to the care of the stroke patient, this is a natural fit. Although leadership by an expert in nursing practice is essential to a stroke program, other clinical team members may be impactful as a stroke coordinator. Spectrum Health in Grand Rapids, MI elected to fill a stroke program coordinator position with an occupational therapist (OT), and partnered this position with a clinical nurse specialist (CNS). OTs receive education in anatomy, physiology and disease process. OTs are also trained in task analysis and take a systematic approach to understanding the dynamic interaction between person, task and environment. These skills, coupled with the clinical expertise of a CNS has impacted stroke practices, processes and team interactions, and helped re-define the role of a ‘stroke program coordinator’.

Purpose:
The purpose is to inform the audience of the novel stroke program leadership pairing of an OT and a CNS.

Methods:
An analysis of stroke program coordinator duties was conducted. Within this analysis, duties conducted by the OT and CNS (as stroke coordinators) were described, with analysis of how these tasks complimented their professional training and the performance of the stroke program.

Results:
The duties of a stroke program coordinator were separated into two concepts: practice and process. Practice includes the care of the stroke patient, administration of medications and utilization of the electronic medical record. Process relates to the flow and organization of care, from the emergency department, acute care and community, and the interactions between the clinical team (nursing, providers and pharmacy). The CNS owns the practice piece, and the OT addresses the process piece within the Comprehensive Stroke Program at Spectrum Health.

Conclusions:
Understanding program priorities is essential to the development of a stroke program coordination team. Once priorities are established, it may be appropriate to consider clinicians outside of nursing to fulfill role on the stroke leadership team. An OT is one of the other healthcare professionals that have the training to assist in the progression of stroke care processes for optimal patient outcomes.
Abstract TP497: The Development and Implementation of a Pediatric Stroke Pathway
Authors: Mills Michele G , Kato Kimberly , Prendergast Erica , Kurz Jonathan
Published: January 2019

Introduction:
Diagnostic delay is a common difficulty in pediatric stroke care, driven by poor recognition, non-specific symptoms, and difficulty obtaining magnetic resonance imaging (MRI). In prior studies, pediatric stroke algorithms improved recognition and decreased diagnostic delay. Our hospital recently developed a pediatric stroke care guideline incorporating a fast MRI protocol. This study presents the process of algorithm development, barriers to implementation, and effects of the guideline on stroke care.

Methods:
Representatives were identified from neurology, critical care, cardiology, emergency medicine, hematology, nursing, pharmacy, radiology and quality improvement. The group was surveyed to identify algorithm goals and barriers to implementation. An algorithm and order sets were developed to provide children with an acute focal neurologic deficit immediate neuroprotective care and urgent MRI. New MRI workflows, metal screening protocols, and a rapid MRI sequence (including diffusion and gradient echo) that did not require sedation were implemented.

Results:
Between October 2017 and June 2018, 55 patients were treated via the new pathway. Median time from presentation to our hospital to diagnostic imaging decreased from 223 minutes to 86 minutes post-algorithm. 20% of children were diagnosed with acute arterial ischemic stroke (AIS). Other diagnoses included migraine (30.9%) and seizure (16.4%). All children with AIS were admitted to the intensive care unit, while no children with migraine or a functional disorder were.

Conclusions:
This study provides a unique description of the steps involved in development and implementation of a pediatric stroke pathway. Implementation of the algorithm decreased time to diagnosis and standardized early treatment. Stroke mimics were common; however, use of the pathway prevented unnecessary admission of children ultimately found to have benign diagnoses.
Abstract TP499: Validation of the Focal Cerebral Arteriopathy Severity Score (FCASS) in a Swiss Cohort: Correlation With Infarct Volume and Outcome
Authors: Slavova Nedelina , Fullerton Heather J , Hills Nancy K , Mackay Mark , Steinlin Maja
Published: January 2019

Introduction:
Treatment trials under development for Focal Cerebral Arteriopathy (FCA)—a unilateral anterior circulation arteriopathy that causes childhood arterial ischemic stroke—require a validated metric for FCA severity. The FCA Severity Score (FCASS) quantifies disease severity and extent. In the derivation cohort, FCASS peaked at 1-4 weeks post-stroke, and maximum FCASS correlated with infarct size and one-year Pediatric Stroke Outcome Measures (PSOM). The goal of the current study was to validate this score in an independent cohort.

Methods:
We used banked neuroimaging and previously acquired 6-month PSOM scores for 32 children with FCA in the Swiss Neuro-Paediatric Stroke Registry (SNPSR). A pediatric neuroradiologist applied FCASS to all available vascular imaging. FCASS sums the individual severity scores (from 0 for no involvement, to 4 for occlusion) for 5 arterial segments (supraclinoid ICA, M1, M2, A1, A2). The same neuroradiologist measured Pediatric ASPECTS scores, a measure of infarct volume (higher scores representing greater volumes, with a maximum possible score of 30).

Results:
Of 32 cases, 6 had only acute vascular imaging (≤1 day post-stroke), and 2 had only delayed vascular imaging (>3 months post-stroke). Including all 32 cases, the maximum FCASS score at any time was a median of 9 (range 3, 15; IQR 6, 12). Maximum FCASS correlated with Pediatric ASPECTS (Spearman’s rho=0.616, p=0.0002; Figure). The median PSOM was 0.5 (range 0 [no deficit], 3 [moderate deficit]; IQR 0, 1.5). Although Pediatric ASPECTS correlated with PSOM (Spearman’s rho=0.623, p=0.0002), there was no direct correlation between maximum FCASS and PSOM (rho=0.25, p=0.185).

Conclusion:
Limitations include a small sample size and missing imaging during the peak FCASS window for 8 of 32 cases. Regardless, in this independent validation cohort, higher maximum FCASS correlated with greater infarct volume scores that also correlated with worse neurological outcomes.
Abstract TP510: “Smoking Paradox” in Stroke Survivors? Uncovering the Truth From a National Stroke Registry Data
Authors: Wen Chi Pang , Wang Hao-Kuang , Hsu Chung Y
Published: January 2019

Objective:
Smokers with stroke were reported to have a better survival than nonsmokers, and this phenomenon was labeled as “smoking paradox”. This study is to assess its validity from a national stroke registry data.

Methods:
A total of 88,925 cases of stroke registered in the nationwide stroke registry system of Taiwan between 2006 and 2016, with 4,169 deaths, were analyzed. Age-specific mortality rate for current, ex- and non-smokers were calculated. NIHSS score (National Institutes of Health Stroke Scale) was measured at 3 months and 6 months Cox model was used to compare complications, mortality and outcomes between smoker and non-smoker ground.

Results:
Smokers constituted more than half of the men (55%) but only 5% of the women. The median age for current smokers was 60.2, for nonsmokers, 71.6, and for ex-smokers, 72.5. Smokers, with nearly 12 years younger than nonsmokers, had smaller mortality rate at younger age groups with fewer deaths, but much larger mortality after age 60, and doubled the mortality rate at the largest group after age 70. Smokers, who quit early, had similar outcome as nonsmokers. When age was controlled, current smokers had worse functional outcome (NIHSS) even at 3 months (adjusted OR, 1.08; 95% CI, 1.02-1.14).

Conclusion:
Smokers, but not ex-smokers, developed stroke 12 years younger than nonsmokers, an ominous sign for smokers. They had higher age-specific mortality rate and poorer outcome than nonsmokers. Quitting early nearly reversed the harms. Smoking paradox does not exist.
Abstract TP515: A New Approach for Inhibiting Hyperglycolysis in Ischemic Stroke: Neuroprotective Effect of Pharmacological Hypothermia with Combined Phenothiazines [Chlorpromazine and Promethazine (C+P)] and Dihydrocapsaicin (DHC)
Authors: Geng Xiaokun , Guan Longfei , Cosky Eric E , Ding Yuchuan
Published: January 2019

Introduction:
Hyperglycolysis, the increase in glucose uptake and metabolism relative to the rate of oxygen utilization, is detrimental because of uncoupling of glycolysis, oxidative phosphorylation and thus lactic acidosis. Therapeutic hypothermia (TH) is one of the most effective neuroprotectants against ischemic injury. However, its clinical use in stroke is restricted due to slow onset, extensive medical and nursing efforts, and complications. Pharmacological hypothermia is an important alternative to induce TH. DHC is a powerful hypothermia inducing agent that targets brain thermoregulation. However, the complications associated with a high dose for achieving TH limited its use. Previous study has showed that C+P decreased brain activity and body temperature. We aimed to establish a therapeutic strategy of synergistic TH for faster cooling and stronger neuroprotection.

Methods:
Sprague-Dawley rats were subjected to 2 h middle cerebral artery occlusion (MCAO) and 6 or 24 h reperfusion, upon which rats intraperitoneally received very low dose of C+P (4 mg/kg), DHC (0.5 mg/kg) or their combination, or inhibitors of glucose transporter 1 and 3 (GLU1/3) (phloretin/cyclin B). Infarct volumes and neurological deficits were examined. Oxidative injury was determined by levels of ATP, lactate, and reactive oxygen species (ROS). Hyperglycolysis was determined by brain glucose, as well as the protein levels of GLUT1, GLUT3, PFK and LDH.

Results:
Body temperature reached the lowest target at 36.5°C by DHC, 35.2°C by C+P, 34°C by combination. Following 6 and 24 h of reperfusion, combination therapy exhibited greater reduction of infarct volume, neurological deficit, brain glucose, lactate and ROS levels, but increased ATP compared to monotherapy. Meanwhile, both DHC and C+P monotherapies reduced GLUT1, GLUT3, PFK and LDH expression, and the reduced expression of these proteins was enhanced by combination therapy. Inhibition of GLUT1 and GLUT3 showed similar trend as the combination therapy group.

Conclusion:
The combination of C+P and DHC enhances the efficiency of TH and efficacy of TH-induced neuroprotection in ischemic stroke. This may be mediated by inhibiting glucose metabolism and associated hyperglycolysis.
Abstract TP520: Walking Pace and the Risk of Stroke: A Dose-Response Meta-Analysis
Authors: Quan Minghui , Xun Pengcheng , Wang Ru , He Ka , Chen Peijie
Published: January 2019

Objective:
To quantitatively assess the available data from prospective cohort studies to estimate the overall association between walking pace and the risk of stroke.

Methods:
PubMed, EMBASE, and China National Knowledge Internet (CNKI) databases were searched for relevant studies through January 9, 2018. Additional studies were obtained from Google Scholar and the related reference lists. Prospective cohort studies that reported the relative risk (RR) and corresponding 95% confidence interval (CI) for the association of interest were included. Summary RR was estimated with random-effects model, and non-linear association was explored with restricted cubic spline.

Results:
A total of 8 studies (9 cohorts) met the pre-specified inclusion criteria, including 136,117 participants and 2,254 stroke events. The pooled RR was 1.84 (95% CI=1.54-2.21) comparing the slowest to the fastest walking pace category. A threshold association was revealed by Spline analysis (
p
non-linearity
=0.01). When walking pace was lower than 4 kilometers per hour (km/h), the stroke risk would increase by 19% with a 1 km/h decrement in walking pace [RR=1.19 (95% CI=1.14-1.25)]. But, the risk of stroke was not appreciably changed when walking pace was greater than 4 km/h. The observed associations were consistent across stroke subtype and sex.

Interpretation:
Findings from this meta-analysis indicate that a walking pace below 4 km/h is associated with elevated risk of stroke.
Abstract TP524: Carotid Intima-Media Thickness Was Significantly Correlated With the 10-Year CVD Risk in Medical Check-Up Participants
Authors: Han Sang Won , Park Joong Hyun , Park Jae Hyeon , Baik Jong Sam , Ahn Seong Hwan , Lee Jong Yun , Lee Kyung-Yul
Published: January 2019

Background:
Carotid intima-media thickness (IMT) can identify subjects at increased atherosclerotic cardiovascular disease (ASCVD) risk and can guide future treatment. However, U.S. Preventive Services Task Force has reaffirmed its previous recommendation against screening for asymptomatic carotid artery stenosis in the general adult population.

Hypothesis:
The aim of the study was to assess the relationship between 10-year cardiovascular risk and carotid IMT in medical check-up participants. The measurement of carotid IMT might be a valuable tool for educating and reducing the CVD risk factors in individual subject.

Methods:
Adults aged 50 to 69 years were eligible for the study if they did not have a history of ASCVD or stroke. The ASCVD risk estimator (http://tools.acc.org/ASCVD-Risk-Estimator) was used for the calculation of the 10-year CVD risk. For the study, the maximum IMT of both carotid arteries were measured and the mean value of them was used for analysis.

Results:
A total of 265 patients were enrolled in this study. The mean age was 58 years, and 28% were women. The mean IMT was significantly correlated with the 10-year CVD risk in all participants (r=0.180, P=0.003). Among men, the mean IMT was 0.81±0.13 mm and 64 (33.5%) participants had ≥10% 10-year CVD risk. Significant difference was observed in the mean IMT between ≥10% 10-year CVD risk group and <10% 10-year CVD risk group (P=0.025). With women, the mean IMT was 0.78±0.10 mm and 6 (8.1%) participants had ≥10% 10-year CVD risk. There was no significant difference in the mean IMT between the groups (p=0.291). In all participants, the cutoff value of the carotid IMT for ≥10% 10-year CVD risk was 0.87 mm (sensitivity, 37.1%; specificity, 87.1%) and area under the ROC curve (AUC) was 0.618 (95% CI, 0.56-0.58, P=0.003). In men, the cutoff value of the carotid IMT for ≥10% 10-year CVD risk was 0.86 mm (sensitivity, 37.5%; specificity, 81.1%). The AUC was 0.606 (95% CI, 0.53-0.68, P=0.015).

Conclusions:
Though routine sonographic screening for carotid artery has little supporting evidence, our study suggested that there may be an opportunity for reducing the rate of ASCVD and stroke through the tailored sonographic examination in high risk subjects.
Abstract TP529: Regional Variability in the Care of Subarachnoid Hemorrhage (SAH) Patients in the United States
Authors: Shah Vishank A , Kazmi Syed Omar , Damani Rahul , Hartsell Alyssa , Hohmann Samuel , Suarez Jose I
Published: January 2019

Introduction:
There is little information regarding the regional variability in care of SAH patients across the US. We hypothesised that variability in clinical care exists across different US regions, which may impact patient outcomes.

Methods:
We conducted a retrospective observational analysis of a cross-sectional cohort generated from the Vizient Clinical Data Base/Resource Manager
TM
comprising data from more than 90% of US academic medical centers, 50 health care systems and 200 community hospitals. The participating hospitals were divided into 4 regions: Northeast(NE), Midwest(MW), South(S), West(W). Demographics, co-morbidities, complications, radiological, pharmacological, surgical interventions, outcomes and costs on all SAH patients between 2009 and 2016 were extracted. Means and percentages for each variable were calculated by region.

Results:
Of 61,946 SAH patients, 62% were female, mean age was 56.8yrs and 62% were white. Highest incidence of SAH was found in S (NE=24%, MW=24%, S=36%, W=16%). Diagnostic neuroimaging was used more commonly in NE and W when compared to the national average (47% vs 44%). In W, aneurysms were more commonly clipped (29% vs 19%). Delayed cerebral Ischemia (DCI) (29% vs 26%) and seizures (15% vs 13%) were more common in W, whereas cerebral edema (33% vs 24%) was more common in S. Vasopressors (65% vs 55%), intra-arterial vasodilators (69% vs 56%) and nimodipine (63% vs 58%) were most commonly used in W, whereas AEDs were most commonly used in MW (63% vs 56%). Hospital mortality was not significantly different(17%) but a higher percentage of patients were discharged to a skilled nursing facility in W (10.9% vs 8.5%).The mean length of stay (NE=16.51, MW=15.17, S=16.59, W=17.49 days) was highest in W. The average total cost was also highest in W when compared to the national average ($96476.71 vs $79884.40).

Conclusion:
There is significant variability in care of SAH patients across different US regions with highest use of resources occurring in W. Despite this, hospital complications such as DCI, discharge disposition and length of stay were slightly worse in W when compared to other regions. These findings might be related to higher rates of aneurysm clipping observed in W. However, prospective confirmation is needed.
Abstract TP533: Decreasing Treatments for Subarachnoid Hemorrhage at Highest Volume Centers: A 10-Year Cohort Study
Authors: Rosenbaum-HaLevi David , Chen Peng R , Blackburn Spiros , Liang Conrad , Bambhroliya Arvind B , Vahidy Farhaan S , Savitz Sean I , Sheth Sunil A
Published: January 2019

Introduction:
With increasing availability of endovascular aneurysm treatments away from tertiary referral centers, greater numbers of patients with aneurysmal subarachnoid hemorrhage (SAH) may be treated at lower-volume centers. This trend over time as well as its influence on patient outcomes remains poorly characterized.

Methods:
Using administrative data on all discharges from hospitals in New York (2005-2014) and Florida (2005-2015), we identified patients with treated aneurysmal SAH. Primary outcome was in-hospital mortality. Patients with trauma were excluded. Logistic regression adjusted for comorbidities was used to assess the relationship of hospital volume on outcome. Results are provided as median [IQR], mean ± SD and OR [95% CI].

Results:
Among 12,290 patients with aneurysmal SAH, 69% were female and median age was 55 [46 - 65]. 62% were treated with endovascular coiling (EC) and 37% with surgical clipping (SC). Over the time span of the study, the number of hospitals treating SAH did not increase (88 vs. 71, 2005 vs. 2014), nor did the number of patients with SAH (1159 vs. 1212, 2005 vs. 2014). Hospitals that treated fewer numbers of patients with SAH annually were more likely to perform SC than EC (51% vs. 40%, 1-10 vs. ≥ 40 annual SAH treatments, p<0.001). Over the course of the study, mean annual SAH treatments per hospital decreased (38 ± 23 vs 34 ± 18, 2005 vs. 2014, p<0.0001) with fewer SAHs treated at the highest volume centers and increasing numbers at intermediate volume centers (Figure). In adjusted logistic regression, the likelihood of in-hospital mortality decreased with increasing annual SAH treatment volume (-3.3% per 10 SAH admissions/year, p<0.05).

Conclusion:
In this 10-year observational cohort, lower volume hospitals were more likely to perform SC, and fewer SAH patients were treated at the highest volume centers over time. These findings corroborate a de-centralization of SAH care, which may be associated with worse outcomes.
Abstract TP543: Trends of Peripheral Blood Indices in Predicting Delayed Cerebral Ischemia After Aneurysmal Subarachnoid Hemorrhage
Authors: Hathidara Mausaminben , Chandrashekhar Swathy , Xu Chao , Ray Bappaditya
Published: January 2019

Introduction:
Cerebral micro-thrombosis and inflammation are leading mechanisms for delayed cerebral ischemia (DCI) after aneurysmal subarachnoid hemorrhage (aSAH). Apart from these local events, clinical and radiological severity of aSAH determines both DCI and systemic inflammatory response. Peripheral blood indices (PBI), e.g. mean platelet volume to platelet count (MPV:PLT) ratio, neutrophil count to lymphocyte count ratio (NLR), platelet count to lymphocyte count ratio (PLR) are established biomarkers for systemic thrombogenic potency and inflammation respectively.

Hypothesis:
We assessed if trends in any and/or combination of these PBI along-with admission characteristics predicted DCI after aSAH.

Methods:
PBI trend during the first 14 days of a retrospective cohort of 166 patients over 6.5 years was used to construct regression models to assess their sensitivity and specificity in predicting DCI.

Results:
Average age of the cohort was 52.9±13.3 years with 69.3% being women, 130 (78.3%) patients presented with H&H I-III and 68 (41.0%) developed DCI. Nonlinear regression showed a significant rise in MPV:PLT upto 2.4 (p-value <0.0001) and a corresponding decline in NLR upto 5.1 (p-value <0.0001) days post-aSAH respectively. Although no definite transition day was observed for PLR, but a fitted linear mixed model showed a PLR rise of 2.79 units/day [95% CI (0.67, 4.90)] as compared to -0.82 units/day [95% CI (-2.64, 0.99)] in DCI vs. non-DCI groups. There was a significant difference of 3.6 units/day in the average change between two groups [t-test p-value 0.01; 95% CI (0.81, 6.40)]. A stepwise logistic regression model constructed using transition day and slope prior to transition day for MPV:PLT, NLR, PLR along with several other patient admission characteristics. The AUC of such prediction models at different step increased from 0.737 to 0.952. A threshold of 0.533 predicted the occurrence of DCI with 91.8% sensitivity and 89.4% specificity.

Conclusion:
The present study substantiates feasibility of using common and simple laboratory test results like PBI in predicting DCI after aSAH and potential role of logistic regression models in development of prognostic models for machine learning algorithms.
Abstract TP546: Association of Near-Infrared Spectroscopy Defined Regional Cerebral Oxygen Saturation with Progression of Cerebral White Matter Hyperintensity Lesions in Comatose Patients
Authors: Nagy Muhammad , Henninger Nils , Ziai Wendy , Hogue Charles W , Geocadin Romergryko , Healy Ryan J , Palmisano Caitlin , Radzik Batya R , Anderson White Mirinda , Mirski Marek , Rivera-Lara Lucia
Published: January 2019

Background:
Real-time regional cerebral oxygen saturation (rScO
2
) measurement using near-infrared spectroscopy (NIRS) may aid in the identification of intracerebral ischemia in critically ill patients. Ischemia to the cerebral white matter results in injury detectable by brain MRI as white matter hyperintensities (WMH). We hypothesized that rScO
2
as assessed by NIRS correlates with the degree of WMH progression in patients admitted to a neurocritical care unit (NCCU).

Materials and Methods:
Retrospective study of eight comatose patients (Glasgow Coma Scale ≤8) in the NCCU who were continuously monitored for three days after their coma onset with NIRS to assess rScO
2,
and who had a brain MRI upon admission and before their hospital discharge. Semi-automated volumetry based on intensity thresholding was used to quantify the WMH volume on FLAIR sequences. The degree of WMH progression was calculated by subtracting the WMH volume of the admission MRI from discharge MRI. Spearman rank correlation was used to determine the strength of association between the rScO
2
(averaged over the monitoring period) and the degree of WMH progression.

Results:
The median averaged rScO
2
was 61 (IQR (48-73) and the lowest 45. Overall, rScO
2
inversely correlated with WMH progression (rho -.738,
p=
0.037); i.e., a lower rScO
2
was associated with greater WMH progression (Figure 1). Patients with greater WMH progression had a worse modified Rankin Scale on discharge (rho .769,
p=
0.026).

Interpretation:
Our study provides proof of principle that rScO
2
as assessed by non-invasive NIRS monitoring may aid detection of cerebral white matter injury.
Abstract TP549: Lymphocyte Count Predicts Poor Clinical Outcome in Patients With Vasospasm Following Subarachnoid Hemorrhage
Authors: Gordon Weston , Massey Brenton , Sharma Kartavya , Abraham Michael
Published: January 2019

Background:
Cerebral vasospasm remains a significant cause of morbidity and mortality in patients after aneurysmal subarachnoid hemorrhage (aSAH). Recently, there has been growing interest in the associations between development of vasospasm and inflammatory cytokines, leukocytes, and pro-thrombotic pathways. Thus far, these investigations have been confined to the prediction of vasospasm and delayed cerebral ischemia rather than the prediction of clinical outcome. We aimed to identify various hematologic predictors of clinical outcome in patients diagnosed with cerebral vasospasm following aSAH.

Methods:
All aSAH patients between 2009-2016 at our institution were reviewed. Patients with symptoms and radiographic evidence of cerebral vasospasm were identified. We assessed baseline and outcome data, including patient demographics, initial aneurysm specifications, management of aSAH and subsequent vasospasm(s), hematologic variables, and 90-day functional outcome (modified Rankin Scale 0-6).

Results:
One-hundred-ten patients with cerebral vasospasm were identified. Forty-three patients had a mRS score of 3-6 at 90 days following discharge. In multivariate logistic regression analysis, lymphocyte count on day of aSAH (OR=4.82, CI 95% 1.68—13.89), high Hunt-Hess grade (OR=4.23, CI 95% 1.19—15.03), external ventricular drain use (OR=11.18, CI 95% 1.27—98.42), and severe vasospasm (OR=8.25, CI 95% 2.26—30.13) were found to be predictors of poor clinical outcome.

Conclusions:
Elevated lymphocyte count following aSAH was associated with a significantly higher rate of poor clinical outcome in patients who developed vasospasm. Several studies have focused on various inflammatory markers, but little attention has been paid to lymphocyte count. Closer monitoring with a lower threshold for endovascular treatment may be indicated in this patient population and could improve clinical outcomes.
Abstract TP55: Comparable Benefit of Endovascular Therapy for Large Vessel Occlusion in Telestroke Patients
Authors: Moustafa Haidar , Barlinn Kristian , Prakapenia Alexandra , Siepmann Timo , Haedrich Kevin , Pallesen Lars-Peder , Wojciechowski Claudia , Gerber Johannes , Puetz Volker , Linn Jennifer , Barlinn Jessica
Published: January 2019

Introduction:
A recent exploratory analysis suggested comparable outcomes among ischemic stroke patients undergoing endovascular therapy (EVT) for anterior circulation large vessel occlusion (acLVO), regardless whether selected via telestroke or admitted directly to an EVT-capable stroke center. The aim of this study was to determine the benefit of EVT in prospectively registered telestroke patients undergoing EVT for acLVO.

Methods:
We studied consecutive patients with acLVO who underwent EVT at our tertiary stroke center between January 2016 and March 2018. All transferred patients received repeated vascular imaging at our center. We compared clinical and imaging variables as well as safety and efficacy outcomes including symptomatic intracranial hemorrhage (sICH), major reperfusion (mTICI 2b/3), 90-days favorable functional outcome (mRS ≤2) and 90-days survival between patients transferred from telestroke hospitals and patients directly admitted to our stroke center.

Results:
Of 513 prospectively registered ischemic stroke patients screened for EVT eligibility during the 27-months study period, 164 had acLVO and eventually underwent EVT: median age 76 years (interquartile range, 66-82); 46% men; median NIHSS score 17 (13-20) points. Of these patients, 73 (44.5%) were transferred from a telestroke hospital and 91 (55.5%) were directly admitted to our tertiary stroke center. While telestroke patients had longer onset-to-needle (median: 128 [95-150] vs. 103 [87-122] min; p=0.051) and onset-to-groin puncture (median: 295.5 [248-340] vs. 180 [132-220] min; <0.0001) times than directly admitted patients, no further differences (p>0.05) in clinical and imaging variables were present between the two groups. The rates of sICH (2.7% vs. 1.1%; p=0.586), major reperfusion (80.8% vs. 76.9%; p=0.545), 90-days favorable functional outcome (23.9% vs. 28.9%; p=0.481) and 90-days survival (73.2% vs. 67.0%; p=0.393) were similar between telestroke and directly admitted patients.

Conclusions:
Our prospective data confirms that telestroke and directly admitted ischemic stroke patients have comparable outcomes following EVT for acLVO.
Abstract TP565: Delayed Administration of Angiotensin Receptor (AT2R) Agonist C21 Downregulates Diabetes Induced Pro-Inflammatory Microglia Activation to Improve Cognitive and Functional Recovery Post-Stroke
Authors: Jackson Ladonya , Dong Guangkuo , Fagan Susan C , Ergul Adviye
Published: January 2019

A disabling consequence of stroke is cognitive impairment, occurring in 12%-48% of patients, for which there is NO therapy. A critical barrier is the lack of understanding of how vascular cognitive impairment & dementia (VCID) develops. While 70% of stroke victims present with comorbid diseases such as diabetes & hypertension, the limited use of comorbid disease models in preclinical research further contributes to this lack of progress. We hypothesized that diabetes exacerbates the development of VCID through chronic activation of a pro-inflammatory M1-like microglia, & that this can be therapeutically targeted with Angiotensin Receptor (AT2R) Agonist C21.

Methods:
Diabetes was induced in male Wistar rats by a high-fat diet & low dose streptozotocin combination. At 12-14 weeks of age a total of 69 control & diabetic rats were subjected to 1 hr middle cerebral artery occlusion (MCAO) or Sham surgery. Adhesive removal task & 2-trial Ymaze were utilized to test sensorimotor & cognitive function. 3 days post-MCAO, rats that met the inclusion criteria were administered C21 or saline in drinking water at a dose of 0.12 mg/kg/day. Cell suspensions from freshly harvested brains were analyzed by flow cytometry utilizing antibodies against cell surface markers for residential M1 microglia (CD45, TMEM119, CD206) & intracellular markers (TNFα and IL-10).

Results:
Untreated control rats progressively recovered from stroke-induced functional deficits by week 4, while untreated diabetics did not. 2 weeks post-MCAO both untreated control & diabetic rats exhibited a significant decline in sensorimotor (P < 0.01 control, 0.05 diabetic) and cognitive function (P < 0.05 control, 0.01 diabetic) compared to Shams. C21 treatment halted the decline and improved sensorimotor (P < 0.05 controls, 0.05 diabetics) and cognitive function (P < 0.05 controls, 0.05 diabetics). Flow cytometry analyses indicate that C21 treatment reduced M1-like activation in the ipsilateral prefrontal cortex & the contralateral hippocampus of diabetic rats (P < 0.05, 0.05). No differences within the control groups were observed.

Conclusion:
Delayed administration of C21 halts the progressive decline of functional & cognitive deficits & downregulates chronic M1-like activation in diabetic stroke.