bluuebunny/crossref_metadata_2025 huggingface dataset:
Abstract TP179: Selecting an Outcome for Sleep Apnea Treatment Trials in Stroke: A Comparative Analysis
Authors: Brown Devin L , Shafie-Khorasani Fatema , Kim Sehee , Sanchez Brisa , Case Erin , Soto Pablo , Chervin Ronald , Lisabeth Lynda
Published: January 2019

Introduction:
Post-stroke sleep apnea (SA) affects the majority of stroke patients and is associated with poorer stroke outcomes. To select appropriate endpoints for a future SA treatment trial in stroke patients, we assessed the predictive ability between a variety of important outcome measures and SA severity, as measured by the apnea-hypopnea index (AHI), within a population-based stroke study.

Methods:
Ischemic stroke patients enrolled in the Brain Attack Surveillance in Corpus Christi (BASIC) project were offered SA screening shortly after stroke with a portable sleep apnea test (ApneaLink Plus). Apnea-hypopnea index (AHI) was calculated as the sum of apneas and hypopneas during the nocturnal recording. Subjects had baseline information collected from chart abstraction and interview, and had 3-month outcomes assessed in-person including an activities of daily living (ADL)/instrumental ADL(IADL) scale, NIHSS, Modified Mini-Mental State exam (3MS), and 12-item Stroke-specific Quality of Life scale (SSQOL). Predictive R
2
(a measure of how well models predict responses for new observations) from linear regression models was used to compare predictive ability of models with and without AHI, adjusted for significant predictors of outcome.

Results:
Within 455 subjects, the predictive R
2
was 31.7% for ADL/IADL, 23.2% for SSQOL, 25.0% for the 3MS, and 11.7% for NIHSS in the model without AHI. When AHI was included in the models, the predictive R
2
increased to 32.8% for ADL/IADL and increased to 11.9% for NIHSS; however, the predictive R
2
decreased by 0.1% for SSQOL and decreased by 0.2% for 3MS.

Conclusions:
In future trials that test SA treatment’s effect on stroke outcomes at 3 months, improvement is most likely to be observed from a functional outcome, such as that measured by the ADL/IADL scale.
Abstract TP185: Acute Infarct Location and Volume Predicts Rehab Outcomes After Ischemic Stroke
Authors: Lin Chen , Chatterjee Neil , Lee Jungwha , Harvey Richard L , Prabhakaran Shyam
Published: January 2019

Objective:
We evaluated the association between acute infarct location and volume with outcome measures during inpatient rehabilitation facility (IRF) in ischemic stroke patients.

Methods:
Between 2012 and 2014, we prospectively enrolled consecutive acute ischemic stroke (AIS) patients admitted from a Comprehensive Stroke Center and followed to an IRF in Chicago, Illinois. Their lesion locations and infarct volumes were calculated. The Functional Independence Measure (FIM) measure was extracted. We analyzed the association between acute infarct characteristics and functional measures using adjusted Spearman’s correlation.

Results:
Among 162 AIS patients (mean age 67.6 years, 48.1% male, 58.6% Caucasian), the median FIM was 52 (IQR 36-62). In adjusted analysis, patients with larger infarct volumes in the left basal ganglia (

r
s

=-0.44, p=0.02) and frontal lobe (

r
s

=-0.35, p=0.04) had lower FIM scores.

Conclusions and Relevance:
There is a strong association between acute infarct volume and specific locations and subsequent FIM scores assessed during AIF. Our findings indicate that functional outcomes can be predicted earlier using index stroke imaging, opening opportunities for targeted rehabilitation.
Abstract TP187: Trimethylamine-N-oxide Values Are Increased in Patients With Acute Ischemic Stroke but Decrease Significantly Within the First Days
Authors: Mundiyanapurath Sibu , Schneider Christine , Hauke Jana , Monostori Peter , Schwarz Kathrin , Nürnberg Christina , Okun Jürgen
Published: January 2019

Introduction:
Trimethylamine-N-oxide (TMAO ) is a biomarker of the gut microbiome and has been reported to be associated with cardiovascular diseases. However, there have been conflicting reports regarding its association with ischemic stroke. As TMAO values could be elevated before stroke or change after stroke we aimed at analyzing the early time course of TMAO values after acute ischemic stroke.

Methods:
In this prospective ongoing case-control study, we included patients with ischemic stroke within the first 24 hours after last-seen-well and control patients treated for other neurologic disorders with only few cardiovascular risk factors at a tertiary care university hospital. The TMAO-values on admission and after 48 hours were analyzed. Patients and controls were excluded if they were treated with antibiotics within the last 30 days and if they were treated with probiotics or chemotherapy.

Results:
99 patients have been recruited so far (63 stroke patients and 36 controls). The median NIHSS score in stroke patients was 3 (interquartile range: 1-8). 89% of the stroke patients vs. 94% of the control group had a normal kidney function. Stroke patient had significantly higher median TMAO values compared to control patients: 5.4 (3.0-8.0) vs. 2.8 (1.6-5.0) μmol/l, p=0.002. Interestingly, there was a significant decrease in TMAO values in stroke patients from admission to 48 hours after the stroke (median decrease 0.7 (0.6-4.2) p=0.004), which was not found for the control group (median decrease 0.1 (-0.9-1.3), p=0.758). In consequence, there was no significant difference between the groups for the TMAO-values after 48 hours (3.4 (2.5-5.1) vs. 3.0 (1.6-4.5) μmol/l, p=0.081).

Conclusion:
This study emphasizes the importance of the TMAO time course after stroke. TMAO values decrease dramatically within the first days after stroke which makes it essential to standardize the time point of analysis to ensure comparability in future studies.
Abstract TP19: Impact of Single-Pass Complete Reperfusion on Clinical Outcomes in Emergent Large Vessel Occlusion (ELVO) Patients Treated With Mechanical Thrombectomy (MT)
Authors: Pandhi Abhi , Tsivgoulis Georgios , Goyal Nitin , Krishnan Rashi , Ishfaq Muhammad , Swatzell Victoria , Katsanos Aristeidis , Krishnaiah Balaji , Nickele Christopher , Inoa Violiza , Elijovich Lucas , Alexandrov Anne W , Alexandrov Andrei V , Arthur Adam S
Published: January 2019

Introduction:
There is mounting evidence indicating that first pass (FP) complete reperfusion (CR) may reduce peri-procedural complications for emergent large vessel occlusion (ELVO) patients treated with mechanical thrombectomy (MT). We investigated the impact of device passes (DP) on the clinical outcomes of ELVO patients who achieved CR following treatment with MT in a high-volume tertiary care stroke center.

Methods:
Consecutive ELVO patients with CR (modified Thrombolysis in Cerebral Infarction grades IIb/III) at the end of MT were evaluated during a five-year period. Baseline stroke severity was assessed by NIHSS-score. The numbers of DP during the procedure were documented. Standard safety outcomes included symptomatic Intracranial Hemorrhage (sICH) by SITS-MOST criteria and three-month mortality. Standard efficacy outcomes included neurological improvement at 24 hours (determined by the relative reduction in NIHSS-score compared to baseline) and functional improvement at three months [determined as the shift in modified Rankin Scale (mRS) scores].

Results:
Among 258 ELVO patients achieving CR during MT the rate of FPCR was 67% (n=173). Patients with FPCR had greater median relative NIHSS-reduction at 24 hours (46% vs. 33%; p=0.033), lower median mRS-scores at three months (2 vs. 3; p=0.034) and lower three-month mortality rates (12% vs. 26%; p=0.005) compared to the rest. The two groups did not differ in sICH rates (5% vs. 10%; p=0.200). FPCR was associated with lower odds of three-month mortality (OR:1.64; 95%:1.03-2.61; p=0.036) on multivariable logistic regression models adjusting for potential confounders (demographics, risk factors, occlusion site, collateral status, stroke severity, onset to groin puncture time, baseline blood pressure and serum glucose values).

Conclusions:
FPCR appears to impact favourably clinical outcomes in ELVO patients treated with MT. CR following FP results in greater neurological and functional improvement at 24 hours and 3 months respectively.
Abstract TP20: Computed Tomography Perfusion Cerebral Blood Flow < 30% of ≥ 70cc Predicts Poor Functional Outcome in Early Window Endovascular Therapy Despite Favorable ASPECTS Score
Authors: Bodle Jeffrey , Hines Andrew , Stanazai Khalid , Strong Edwin , Rhoten Jeremy , Karamchandani Rahul , Clemente Jonathan , Asimos Andrew
Published: January 2019

Introduction:
Endovascular Therapy(EVT) has been shown to be efficacious for treatment of large artery occlusion (LAO) acute ischemic stroke (AIS). The 2018 American Heart Association Guidelines for Management of Acute Ischemic Stroke recommend EVT for patients with anterior circulation LAO AIS with ASPECTS ≥6 and groin puncture within 6 hours of symptom onset. CT Perfusion (CTP) pattern with CBF < 30% of ≥ 70cc is a predictor of a large core infarction. Patients within 6 hours of symptom onset with LAO AIS with favorable ASPECTS on non-contrast head CT and large core infarct measurements on CTP may present a decision-making challenge.

Hypothesis:
CTP CBF < 30% of ≥ 70cc predicts poor functional outcome in anterior circulation LAO AIS with ASPECTS ≥6 with groin puncture for EVT within 6 hours of symptom onset.

Methods:
From a large healthcare system’s stroke network database, we conducted a retrospective analysis of functional outcomes (90 day mRS) of patients who presented with LAO AIS with ASPECTS ≥6 with CBF < 30% of ≥ 70cc who underwent EVT with groin puncture within 6 hours from symptom onset between July 2016 and March 2018.

Results:
Over a 21-month period, 12 cases were identified with CBF < 30% ≥ 70cc and ASPECTS ≥ 6 who underwent EVT within 6 hours of symptom onset. Mean and median CBF < 30% were 119.8 cc and 99 cc, while mean and median ASPECTS scores were 9.3 and 10. TICI 3 revascularization was achieved in 6 patients, and TICI 2B was achieved in 3 patients, within one patient each achieving TICI 2A, TICI 1 and TICI 0. Mean and median mRS at discharge were 4.2 and 4, while mean and median 90 day mRS were 4 and 3. Of the five patients who died, none sustained parenchymal type 2 hemorrhages, and two had TICI 2B, two had TICI 3, one had TICI 0 revascularization.

Conclusions:
In our experience, most patients presenting within 6 hours of symptom onset with a CBF < 30% of ≥ 70cc and an ASPECTS ≥6 achieved poor functional outcomes (mRS of >2) despite overall good rates of revascularization.
Abstract TP200: Short-term Outcomes in Patients With Cannabis Use and Acute Ischemic Stroke
Authors: Savani Chirag , Kumar Varun , Yi Xiyan , Singh Tejinder , Chib Anjula , Pathak Ambarish , Renati Swetha
Published: January 2019

Background:
As the use of cannabis is legalized in many areas, it is important to understand the effect of cannabis use on acute ischemic stroke (AIS) patients as compared to non-cannabis users.

Methods:
Nationwide Readmission Database from 2010-14 was used to identify patients with AIS using appropriate ICD 9 CM codes in primary diagnosis field and cannabis abuse with ICD 9 CM code 305.3x, 305.2x in secondary diagnosis field. Predictors to assess the association between cannabis abuse and 30-day readmission were analyzed using multivariable logistic regression model. Differences between categorical variables were tested using the chi-square test and continuous variables using the Student t-test.

Results:
We identified 1958231 AIS patients in our study period, of which 17224 had a history of cannabis use (Mean age 51 years, 71.4% were male) with a rising trend of hospitalization (from 2633 patients in 2010 to 4630 patients in 2014, ptrend <0.0001). Cannabis-AIS group was associated with lower 30-day readmission (9.9% vs 11.9%; p <0.0001), and lower in-hospital mortality (2.9% vs 5.2%; p<0.0001). However they had a longer mean length of stay (8 vs 7 days; p <0.0001), and higher cost of hospitalization (10742 vs 9449 dollars; p<0.0001) as compared to non-cannabis use-AIS group. Multivariate analysis showed cannabis use paradoxically reduces risk of 30-day readmission post AIS (OR 0.89, 95% CI 0.82-0.96; p=0.003). Intravascular thrombolysis utilization in these patients was predictor of decreased readmission (OR 0.88, 95% CI 0.86-0.99; p<0.0001). We also observed a rising trend in the utilization of intravascular thrombolysis (9.3% in 2014 vs 6.2% in 2010; p <0.0001) and mechanical thrombectomy (1.7% in 2014 vs 0.5% in 2010; p<0.0001).

Conclusion:
Our study showed increased numbers of patients with cannabis use and AIS during our study period. Based on this data, thrombolysis in this group is safe and not associated with worse outcome. As cannabis use becomes legalized in areas of the country this is an important area of study.
Abstract TP203: Serum Uric Acid is Associated With Arterial Stiffness, Pulse Pressure and Stroke in Apparently Healthy Population
Authors: Park Kwang-Yeol , Kim Jeong-Min , Yoon Won-Tae , Chung Pil-Wook
Published: January 2019

Introduction:
Serum uric acid has been reported to be associated with arterial stiffness and cardiovascular disease in previous studies. However, some of them showed contradicting results. Also, some studies reported gender difference in the association between uric acid and vascular disease. We investigated whether serum uric acid is associated with arterial stiffness, blood pressure, and stroke in both genders.

Methods:
A total of 54,164 subjects who underwent health check-ups including brachial-ankle pulse weave velocity (baPWV) between 2004 and 2015 were enrolled. The average of the baPWV values obtained on both sides was used for further analysis. Past medical history was investigated through interview. Multivariable linear and logistic regression were used for the evaluation of association between serum uric acid and vascular outcomes.

Results:
Mean age was 45 ± 12 and male was 45,941 (85%). History of hypertension was in 10,278 (19%) and stroke in 460 (0.9%). Systolic blood pressure was 118 ±13 and diastolic blood pressure was 75 ± 9. baPWV was 1387 ± 223 cm/s. On multivariable linear regression, serum uric acid was associated with baPWV (beta 14.1; 95% CI 9.45 - 18.8), systolic blood pressure (beta 0.82; 95% CI 0.50 - 1.15), diastolic blood pressure (beta 0.57; 95% CI 0.34 - 0.80), and pulse pressure (beta 0.25; 95% CI 0.04 - 0.47). When we performed the same analyses in population without hypertension and stroke, the results did not change. On multivariable logistic regression, serum uric acid was associated with hypertension (odds ratio 1.42; 95% CI 1.33 - 1.51) and stroke (odds ratio 1.30; 95% CI 1.03 - 1.63).

Conclusion:
We showed that serum uric acid is significantly associated with arterial stiffness, various measures of blood pressure, hypertension and stroke in this single large cohort, irrespective of gender.
Abstract TP216: Neighboorhood Disadvantage is Associated With Hemorrhagic Stroke in Young Adults
Authors: Iwuchukwu Ifeanyi O , Danos Denise , Coleman Jessica , Gilliland Aubrey , Forsman Katie , Tran Vi , Nguyen Doan , Scribner Richard
Published: January 2019

Introduction:
Not only is hemorrhagic stroke (HS) in the young adult (≤50 years) frequently devastating, a racial disparity is established in this population. Traditional risk factors do not account for the disparity. The importance of environmental stressors in disease processes is recognized. Hence, we explored the hypothesis that neighborhood disadvantage, a measure of environmental stress, is associated with HS in young adults.

Methods:
We utilized demographic and clinical data from a prospective study of HS patients (spontaneous intracerebral and aneurysmal subarachnoid hemorrhages) at our institution between July 2015-December 2017. Patients were geocoded to 2010 US census tracts by address. Neighborhood concentrated disadvantage index (CDI) was calculated according to the PhenX Toolkit protocol using US Census data. Univariate comparisons were performed via Chi-square and t-tests. Multivariable logistic regression was used to analyze the probability of HS at an early age (≤50). All analyses were performed using SAS version 9.4.

Results:
141 HS patients were enrolled; however, 15 non-Louisiana residents were excluded. Of 103 Louisiana residents, 53(51.5%) identified as white and 44(42.7%) as black race. Other races/ethnicities (n=6) were excluded due to small numbers. The proportion of Black patients aged 50 or younger was significantly greater than white patients (43% vs. 15%). Though not significant, males were more likely to experience HS at a young age. CDI scores were significantly higher, indicating greater neighborhood disadvantage, among patients ≤50 [mean CDI: 0.42 v -0.18]. Multivariable logistic regression results indicated that controlling for sex, the odds of HS at a young age were 4 times greater for blacks compared to whites [OR: 4.11 (1.55,10.94)]. While the association between CDI and HS at a young age was only marginally significant in the multivariable model (p=0.12), controlling for CDI did reduce the racial disparity [OR: 2.78 (0.94, 8.22)].

Conclusion:
Our results suggest that differential exposure to neighborhood disadvantage is a contributing factor to the profound racial disparities for HS in individuals aged 50 or younger. More research is needed to determine distinct risk profiles for HS in this age group.
Abstract TP224: The Impact of Cerebral Microbleeds on Outcomes of Non-cardiogenic TIA and Minor Ischemic Stroke
Authors: Sakuta Kenichi , Sato Takeo , Komatsu Teppei , Sakai Kenichiro , Terasawa Yuka , Mitsumura Hietaka , Iguchi Yasuyuki
Published: January 2019

Background:
The relationship between cerebral microbleeds (CMBs) and risk of early recurrence of ischemic stroke in patients with transient ischemic attack (TIA) or ischemic stroke is still controversial, and as is the effect for the prognosis. Our aim is to verify the relationship between CMBs and outcome in patients with TIA and minor ischemic stroke.

Methods:
We retrospectively reviewed consecutive patients with non-cardiogenic TIA and minor ischemic stroke (NIHSS <4 on admission), who underwent an initial brain MRI within 48 hours from symptom onset. The patients were divided into two groups according to presence and absence of CMBs and were compared clinical outcomes. Poor outcome was defined as modified Rankin scale 4-6 at 90 days after symptom onset. Logistic regression analysis was performed to determine the factors for outcome.

Results:
A total of 374 patients (279 men, median age 67 years old) were enrolled in our study. CMBs was observed in 152 patients (41%). Outcome was significantly poor in patients with CMBs (11% vs 3%, P=0.002). Stroke recurrence was frequently observed in patients with CMBs (13% vs 7%, P=0.041). Increased CMBs burden is lineally associated with poor outcome in comparison with absent CMBs (Figure 1). The multivariate analysis revealed that the CMBs was independently associated with poor outcome (OR, 3.86; 95%CI, 1.29-11.53; P=0.015).

Conclusion:
CMBs is the important factor for poor outcome in TIA and minor ischemic stroke, especially in increased CMBs burden patients.
Abstract TP232: Characteristics of Stroke in Women Vary by Race and Ethnicity
Authors: LaHue Sara C , Gautami Richa , Singh Vineeta
Published: January 2019

Objective:
To identify differences in ischemic stroke characteristics, such as risk factors, severity, and type, in a multiethnic population of women.

Methods:
In this retrospective cohort study, all women hospitalized at an urban, public safety net hospital from January 1, 2012 through December 31, 2015 with possible stroke and documented initial NIH Stroke Scale (NIHSS) were ascertained. Male and transgender patients were excluded. Patient charts were reviewed by the coauthors for demographics, stroke risk factors, stroke characteristics and clinical outcomes. Strokes were classified using TOAST criteria. Differences between races/ethnicities were calculated using chi-square, one-way ANOVA or Kruskal-Wallis tests.

Results:
A total of 254 women were included in this study. Mean patient age was 71±15 (range 24-100) years; there was no difference across race/ethnicity [F(3, 254) = 2.40, p=0.068]. Distribution of race/ethnicity was 34% Asian/Pacific Islander (n=87), 23% Hispanic (n=59), 22% Black (n=57), and 20% Caucasian (n=51). Mean initial NIHSS was 10±7; across races/ethnicities, there was no significant difference in NIHSS [F(3, 254) = 0.22, p=0.880] or discharge to self-care [χ
2
(3, n=254) = 1.627, p=0.653]. Significantly fewer Black women were diagnosed with atrial fibrillation [χ
2
(3, n=254) = 13.964, p=0.003], and significantly more Asian women had intracranial atherosclerosis [χ
2
(3, n=254) = 13.857, p=0.003], compared with the other races/ethnicities. Black women were also significantly less likely to have a stroke due to a cardioembolic etiology [χ
2
(3, n=254) = 20.277, p < 0.001] compared with other races/ethnicities. With regard to cerebrovascular risk factors, significantly more Black women had a history of tobacco use [χ
2
(3, n=254) = 16.194, p=0.001); there were no significant differences across races/ethnicities with regard to history of prior stroke, coronary artery disease, carotid disease, diabetes mellitus, hypertension, or hyperlipidemia.

Conclusions:
There were significant differences in stroke risk factors and stroke types between races/ethnicities, especially among Black and Asian women. Identification of these differences is important for targeted stroke prevention.
Abstract TP237: Characterization of Retrieved Thrombus Composition by Morphological, Histopathological and Imaging Analysis in Acute Ischemic Stroke
Authors: Yoon Changhyo , Kim Young Soo , Baik Seung Kug , Jung Seunguk
Published: January 2019

Introduction:
The aim of this study was to assess whether we could distinguish stroke subtype by analyzing the size, weight, shape, color and imaging characteristics of the retrieved thrombus.

Methods:
From October 2013 to January 2016, 28 thrombi were classified as cardioembolism (CE) and 16 were large artery atherosclerosis (LAD). The size, shape, and color characteristics of the thrombus were analyzed. The weight of total thrombi of each case was measured. The weight, length, and sectional area of the largest thrombus of each case was measured again. We compared the degree of circularity, roundness, aspect ratio, and solidity of the largest thrombus. The color image of the largest thrombus was analyzed by using RGB histograms. Retrieved thrombus was subjected to post-MRI under ex vivo conditions.

Results:
The probability of stroke due to CE increases as the RBC composition of thrombus increases, and the probability of stroke due to LAD increases as the fibrin composition of thrombus increases (p=0.018). The size of the cross-sectional area of the largest thrombus (22.38 ±21.48mm2 vs. 12.15±10.86mm2, p=0.043) is larger in the CE group. Also, the weight of total thrombi (140.00±231.39mg vs. 37.50± 30.31mg, p=0.049) and the weight of the largest thrombus (46.14±47.34mg vs. 17.94±16.89mg, p=0.013) is heavier in the CE group. Higher RGB values in the LAD group mean that the thrombus of the LAD group is brighter than the thrombus of the CE group. In multivariate logistic regression analysis, the mean Green value of RGB (OR 1.488, 95% CI 1.032-2.146; p= 0.033) was independently associated with LAD. Blooming artifacts of the post-MRI under ex vivo conditions well correlate with that of the pre-MRI (p=0.016), and blooming artifacts of the post-MRI under ex vivo conditions was associated with red blood cell composition of thrombus (p=0.005).

Conclusions:
The shape of the thrombus did not help to determine the stroke subtype. The weight, cross-sectional area, and color difference of the thrombus helped to distinguish CE and LAD, and the mean Green value of RGB was found to be the most significant predictor. And blooming artifacts of the post-MRI under ex vivo conditions was well correlated with that of the pre-MRI and red blood cell composition of thrombus.
Abstract TP253: Clopidogrel Pharmacogenetics in the POINT Trial
Authors: Meschia James F , Ross Owen A , Walton Ronald L , Farrugia Luca , Easton John D , Elm Jordan J , Farrant Mary , Zurita Karla G , Barsan William G , Kim Anthony S , Lindblad Anne S , Palesch Yuko Y , Johnston S. C ,   POINT Investigators
Published: January 2019

Introduction:
Across 269 international sites, the POINT trial randomly assigned 4881 patients with minor ischemic stroke or high-risk transient ischemic attack to receive either clopidogrel at a loading dose of 600 mg on day 1 followed by 75 mg per day, plus aspirin at a dose of 50-325 mg per day or the same range of doses of aspirin alone. Dual antiplatelet therapy significantly reduced the incidence of major ischemic events, but also significantly increased the incidence of major hemorrhage. Clopidogrel is a prodrug that requires metabolism by the cytochrome P450 complex to act on the P2Y12 platelet receptor. CYP2C19 (cytochrome P450 family 2 subfamily C polypeptide 19) variants are associated with variable rates of metabolism of clopidogrel and thus pharmacogenomic effects may be clinically relevant.

Methods:
Genomic DNA was extracted from peripheral blood monocytes using the standard protocols. Genotyping for CYP2C19 *2, *3 and *17 alleles (rs4244285, rs4986893 and rs12248560) defines metabolizer/activator status and was performed using custom TaqMan Allelic Discrimination Assays on a QuantStudio™ 7 Flex Real-Time PCR System.

Results:
As of June 28, 2018, a total of 445 trial participants had DNA available for analysis. CYP2C19 allele genotyping demonstrated approximately one quarter of subjects (n=127; 28.6%) would be defined as poor or Intermediate metabolizers of clopidogrel.

Conclusions:
Based on targeted cytochrome P 450 genotyping, about one quarter of POINT patients have reduced clopidogrel activation. Additional genotyping is ongoing. We plan to present results assessing whether the treatment effect of clopidogrel is limited to those with CYP2C19 genotypes associated with normal drug metabolism.
Abstract TP259: Discovery of Stroke-Related Blood Biomarkers From Gene Expression Network Models
Authors: Theofilatos Konstaninos , Korfiati Aigli , Mavroudi Seferina , Cowperthwaite Matthew , Shpak Max
Published: January 2019

Introduction:
Identifying the molecular biomarkers characteristic of ischemic stroke has the potential to aid in distinguishing stroke cases from stroke symptom mimics while advancing the understanding of the physiological changes underlying the body's response to stroke.

Hypothesis:
Measures of network centrality can identify a more statistically robust and functionally significant set of molecular biomarkers to distinguish between stroke and non-stroke cases than methods based solely on the absolute magnitudes of gene expression fold-change.

Methods:
Mutual information values for the expression levels of 13243 quantified transcripts were evaluated in blood samples from 128 stroke patients and 67 non-stroke patients to construct co-expression networks of genes. Page rank centrality scores were computed for every gene; a gene’s significance in the network was assessed according to the differences in their network centrality between stroke and non-stroke expression patterns. A hybrid genetic algorithm-support vector machine learning tool (InSyBio) was used to classify samples based on gene centrality in order to identify an optimal set of predictor genes for stroke vs. non-stroke while minimizing the number of genes in the model.

Results:
A predictive model for stroke with 85.7% accuracy was found using 4 network-central genes (
AGTPBP1, SRPK1, ANTXR2, MRPL41
). In contrast, classification models based solely on individual genes identified by significant fold-change in expression level provided predictive accuracies < 70% for any single gene. Models with much larger (10-26) numbers of gene transcript biomarkers gave lower predictive accuracies (≤ 80%) than the 4 network-based gene classification in this study. The 4 genes identified from network centrality were also significantly associated with differential expression in 6 miRNAs, and were involved in key pathways including metal ion binding, translation, and transport across cell/organelle membranes.

Conclusions:
This study provides an improved set of biomarkers that may be clinically useful for diagnosing stroke. Additionally, the set of co-expressed genes identified in this study provides insight into novel pathways that are activated or disrupted as a consequence of stroke.
Abstract TP265: The Impact of Extending the Acute Stroke Triage Criteria to 24 Hours From Last Known Normal
Authors: Beland Dawn K , Nouh Amre
Published: January 2019

Background:
Landmark trials selecting acute ischemic stroke patients with large vessel occlusion with salvageable brain tissue, as determined by CT perfusion, have extended the therapeutic time window for mechanical thrombectomy (MT) from 6 to 24 hours after onset. This prompted extensive change to stroke care paradigms. While the benefit in functional outcomes has been proven, the effect of implementing this evidence-based medicine on care in a large urban university affiliated Level 1 and Comprehensive Stroke Center is not known.

Purpose:
To evaluate the impact on process of care metrics after extending the acute stroke alert from 6 to 24 hours from symptom onset or last known normal.

Methods:
A retrospective QI project evaluating all stroke patients who presented after implementing the extended window at our Comprehensive Stroke Center was developed. All ED stroke alerts presenting from March-August 2017 prior to implementation of the extended time protocol were compared to alerts from October 2017-March 2018 after the extended protocol was implemented. Metrics evaluated and compared between groups included number of stroke alerts, mean times for door to CT, door to decision, decision to drug administration, door to needle for IV-thrombolytic, and door to groin puncture for MTs.

Results:
Although the number of ED stroke alerts increased by 44.1%, this translated into only a 7.3% increase in total acute ischemic stroke treatments (IV tPA, tPA transfers, MTs or a combination) despite a 53.6% increase in MT alone. Increases in mean time (mins) for door to CT (7.4), door to decision (15), door to drug (11.4), and door to puncture (23.3) were observed however decision to administration times remained unchanged.

Conclusion:
Although extended time windows have increased the number of MTs by 53.6%, delays in almost all care metrics were observed. The increase in stroke alerts and patients triaged with acute urgency are a likely cause for delays with more requiring CT upon presentation. Other factors include increased case processing and the additional perfusion imaging required. Review of our process through a Lean Management Kaizen in June 2018 has produced additional resources and novel approaches to handle increases in volume as needed to prevent delays in the ED.
Abstract TP268: Utilization and Appropriateness of Emergency Medical Services Air Transport in Acute Ischemic Stroke Care
Authors: Petrone Ashley , Power Martha , Daniels Debra , Large Michelle , Adcock Amelia
Published: January 2019

Introduction:
Although air (helicopter) transfer is largely accepted as improving outcomes in time sensitive conditions including acute ischemic stroke (AIS), inappropriate triage of these patients when they are ineligible for acute stroke therapies places patients and providers at unnecessary risk and wastes limited healthcare resources. Extension of the endovascular therapy time window to twenty-four hours further increases the burden on stroke systems of care. As the tertiary flagship institution and only comprehensive stroke center (CSC) in a rural state, we sought to identify how accurate our triage system was at identifying ischemic stroke patients appropriate for air transfer.

Hypothesis:
A significant percent of AIS patients inappropriately utilize HelicopterEmergency Medical Services (HEMS). Based on information known prior to transfer, the majority are avoidable.

Methods:
We defined inappropriate utilization basedon time from last known normal (LKN), stroke severity and baseline functional status. A retrospective chart review was performed on all stroke alerts that arrived at our hospital by HEMS in 2017.

Results:
Of the 141 acute stroke patients transferred by HEMS, 23 (16%) were deemed inappropriate; 14 (61% ) were outside the acute treatment time windows for either IV tPA or Endovascular Therapy (EVT); 5(22%) were ineligible for EVT (NIHSS<6); 2 (9%) were ineligible for EVT (mRS≥3); and 2 (9%) were flown despite negative angiographic studies performed at transferring institution. At an average cost of $18,500/flight, $425,500 in total was attributed to inappropriate transport. Thirteen (57%) of the patients were interfacility transfers where the decision to arrange HEMS occurred after a physician’s evaluation.

Conclusion:
HEMS transport for AIS patients plays a crucial role in delivering the best care. However, a significant percent of patients do not meet criteria for its appropriate utilization, most commonly when pre-established LSN are outside of acute treatment windows. Furthermore, inappropriate transfers were initiated in spite of outside hospital physician evaluation over 50% of the time. These results represent a unique opportunity to coordinate education and buildeffective triage paradigmsacross a system of stroke care.
Abstract TP269: Predictors of Drug Screens Among Stroke Patients in the Greater Cincinnati Northern Kentucky Stroke Study: Preliminary Findings for 2015
Authors: Madsen Tracy E , Khoury Jane , Alwell Kathleen , Jasne Adam , Demel Stacie L , De Los Rios La Rosa Felipe , Flaherty Matthew , Ferioli Simona , Moomaw Charles J , Mackey Jason , Slavin Sabreena J , Star Michael , Walsh Kyle , Woo Daniel , Kissela Brett , Kleindorfer Dawn O
Published: January 2019

Introduction:
Previous studies have shown biases in screening for toxicologic substances among stroke patients but have limited generalizability. Our objective was to investigate predictors of the use of drug screens among stroke patients in a large population based study.

Methods:
The Greater Cincinnati Northern Kentucky Stroke Study is a population-based study of stroke cases ascertained from a biracial population of 1.3 million people in a 5-county region of southern Ohio/northern Kentucky. All hospital ascertained cases of stroke (ischemic (IS), transient ischemic attack (TIA), hemorrhagic (ICH), subarachnoid hemorrhage (SAH)), occurring during calendar year 2015 were included. Trained study nurses abstracted data on whether a drug screen was ordered (between emergency department (ED) presentation and hospital discharge). Screening tests for alcohol were not included. Multivariable logistic regression was used to identify predictors of use of a drug screen. Potential predictors were patient sex, age, race, select comorbidities, smoking status, stroke severity (NIHSS), treatment location and stroke type.

Results:
Of 3865 stroke cases (53.8% women, 20.8% black, mean age 69.7(14.8) years), 12.0% had a drug screen performed. Adjusted, black race (aOR 1.93 95%CI 1.52-2.44), current smoking (aOR 1.97 95%CI 1.58-2.47), higher NIHSS (aOR 1.22 95%CI 1.15-1.28 per 5 unit increase) and being treated in an academic ED (aOR 2.04, 95%CI 1.62-2.55) increased the likelihood of a drug screen, while female gender (aOR 0.75 95%CI 0.60-0.93) and older age (aOR 0.61 per 10 years, 95%CI 0.56-0.66) decreased the likelihood.

Conclusions:
In a large population based study of stroke patients, drug screens were more likely to be ordered in men, blacks, smokers, younger patients, and those seen in academic EDs. It is unknown whether these trends are similar among hospitalized patients with other diagnoses. Additionally, current evidence suggests that such differential testing may lead to missed counselling opportunities in those not tested as well as lower likelihood of thrombolytic treatment in those who are tested. Future research should investigate the yield of such drug screens and explore whether guidelines in ordering drug tests could help to avoid testing biases.
Abstract TP281: Implementation of Coordinated Telestroke Program in an Urban Setting Improves Acute Stroke Care
Authors: Zurasky John , Corless Leslie , Lucas Lindsay , Baraban Elizabeth
Published: January 2019

Purpose:
Telestroke has been shown to improve acute ischemic stroke (AIS) care in rural settings, but few studies have examined the impact of telestroke in an urban setting. In an urban area, there was a planned transition from an outpatient-based acute stroke provider pool to a centralized telehealth team of neurovascular and neurocritical care providers. This study assessed the impact of this change by comparing patient outcomes during three time periods: pre-initiation (PRE), transition after initiation (TRAN) and post-transition (POST).

Methods:
Data for AIS patients 18 and older from five urban hospitals were used. Outcomes were hospital length of stay (LOS) and percentage of patients who had a door-to-needle time (DTN) <45 and <60 minutes, IV-alteplase or endovascular treatment, an IV-alteplase-related complication, and a discharge other than to home or rehab. Generalized linear and Cox proportional hazard models were used to compare outcomes for patients discharged during PRE (June 2015 - June 2016), TRAN (July 2016 – December 2016) and POST (January 2017 – March 2018) time periods adjusting for arrival mode, gender, admit NIHSS, age, and arrival time.

Results:
Of 4,984 patients that met inclusion criteria, there were 2,075 treated in PRE, 1,052 in TRAN and 1,857 in POST. After adjustment, TRAN patients were 1.77 times more likely to be treated with IV-alteplase than PRE patients (p=.013). POST patients were 2.46 times more likely to receive endovascular treatment than PRE patients (p=.009) and 2.07 times as likely as those in the TRAN period (p=.007). Patients in the TRAN period were 1.63 times more likely to be treated with IV alteplase in <60 minutes (p<.001) and 2.22 times more likely in the POST period (p=.002) compared to those in PRE. There were no significant differences in the odds of being treated in <45 minutes, LOS, or discharge disposition.

Conclusion:
A transition to a specialty stroke care through a telestroke network showed improvements in treatment rates and percentage of patients with DTN less than 60 minutes.
Abstract TP283: Ambulance Service Use and Associations With Hospital Care and 90-day Outcomes for Acute Stroke: The Australian Stroke Clinical Registry (AuSCR)
Authors: Cadilhac Dominique A , Grimley Rohan , Bladin Christopher F , Donnan Geoffrey A , Hill Kelvin , Levi Christopher R , Middleton Sandy , Anderson Craig S , Lannin Natasha A , Kilkenny Monique F ,   AuSCR consortium partners and Stroke123 investigators
Published: January 2019

Introduction:
Hospital arrival via ambulance may influence treatment options and outcomes of acute stroke. A national study for Australia has not previously been reported, and inclusion of long-term outcomes is rare. We aimed to determine differences in the characteristics of patients and their outcomes by route of hospital presentation.

Methods:
Patient-level data linkage of Australian Stroke Clinical Registry (AuSCR) patients with first-ever strokes between January 2010 and December 2013 (n=40 hospitals) were merged with emergency and hospital admissions, and death records. Multilevel regression models were used to determine associations with hospital care and outcome by type of transport to hospital.

Results:
Among 9315 patients with first-ever stroke, 5601 (60%) arrived by ambulance (52% male; 79% ischemic). Compared to patients arriving by private transport, those arriving by ambulance were older (ambulance, median 77 vs. private, 72 years; P<0.001), more often had an intracerebral hemorrhage (ICH, ambulance 18% vs 15%; P<0.001), and were unable to walk (proxy for stroke severity: ambulance 73% vs. 50%; P<0.001). Median times to hospital were shorter via ambulance (135 vs. 229 mins; P<0.001), and patients arriving by private transport were less likely to receive acute therapies (rtPA for ischemic stroke, ambulance 16% vs 8%; aspirin <48 hrs, ambulance 75% vs 63%) or swallow screen/assessment (ambulance 89% vs 75%). After accounting for patient/hospital characteristics, compared with patients arriving by private transport, those using ambulances more often received inpatient rehabilitation (aOR 1.57, 95%CI 1.30-1.64), but more often died within 30-days (aOR 1.23) or reported worse quality-of-life at 90-180 days (coefficient: -4.4, 95%CI -7.4 to -1.4).

Conclusion:
Patients with first-ever stroke who take private transport to hospital experience treatment disadvantages but not worse outcomes. Public education on calling an ambulance for stroke symptoms remains important.
Abstract TP301: Patient Preferences for Inpatient vs Outpatient Management of TIA and Minor Stroke and Its Association With Psychological Stress
Authors: Chang Bernard P , Willey Joshua , Edmondson Donald , Miller Eliza , Sanchez Gabriel J , Elkind Mitchell S , Kronish Ian
Published: January 2019

Introduction:
Understanding patient preferences may help guide decision making around discharge timing after TIA or minor stroke (TIAMS) and may lead to treatment algorithms with higher patient satisfaction and adherence. Psychological stress, particularly a sense of helplessness and vulnerability (defined as “threat perception”) may be associated with adverse psychological outcomes following TIAMS, including the development of post-traumatic stress. We hypothesized that TIAMS patients with higher threat perception would be more likely to prefer inpatient care over early emergency department (ED) discharge.

Methods:
We analyzed ED patients in a large urban academic medical center with suspected TIAMS (defined as National Institutes of Health Stroke Scale (NIHSS) score of ≤5). Patients reported discharge preferences and completed a validated 7 item self-report scale of threat perception (e.g. “I am worried I am going to die. I feel helpless”).

Results:
302 suspected TIAMS patients were evaluated (mean age: 63.7±15.1, 52% female, 24.8% Black, 48% Hispanic, median NIHSS= 2). 217 patients (70.7%) preferred hospital admission compared to ED discharge. In unadjusted analysis, those who preferred admission had similar ED threat scores compared to those who preferred early discharge (8.1 ±5.2 vs 7.2±4.8; p=0.24). In the adjusted model, threat perceptions remained unassociated with discharge preference, however, women and Hispanics were more likely to prefer inpatient admission (Table 1)

Conclusion:
Overall, TIAMS patients preferred inpatient admission over early discharge. Discharge preference was not associated with higher threat perception. Further research examining potential drivers of patient preferences may inform patient discussions and optimize patient satisfaction with rapid outpatient TIAMS care.
Abstract TP302: Paramedic Detection of Large Vessel Occlusions Using mNIHSS: A Prospective Cohort Pilot Study
Authors: Mulkerin William , Francisco Jonathan , Lima Brandon , Spokoyny Ilana , Gilbert Gregory , Brown Ian , Bernier Eric , Niknam Kian , Govindarajan Prasanthi
Published: January 2019

Modified NIHSS (National Institute of Health Stroke Scale) is a 11-item, 0- 31 point motor stroke deficit scale that was developed to assess stroke severity. Our objective was to test the performance of modified NIHSS (mNIHSS) for the detection of large vessel occlusion when used by paramedics.

Methods:
This is a prospective, cohort study that was conducted in a fire-based EMS agency in California, during a 20-month period (11/2016 - 6/2018). We trained 40 ALS-trained Paramedics in Emergency Neurological Life Support (ENLS) stroke curriculum and the AHA/ASA NIHSS certification program. Patients were eligible if they were over the age of 18 years, with acute neurological deficit consistent with suspected acute stroke. Non-English speaking or vulnerable patients were excluded. The paramedics obtained a stroke-specific history, completed the mNIHSS, and assessed for contraindications for acute stroke treatment. This data was linked with the hospital outcomes using unique identifiers. We calculated the test performance of mNIHSS and NIHSS in the emergency department for LVO using the gold standard CTA imaging. The reliability between paramedic and stroke team mNIHSS scores using a Bland-Altman plot.

Results:
Of the 31 patients, 10 (32.3%) had an LVO on CTA. Of the 10 with LVO, 6 had a mNIHSS of >6 and a test sensitivity of 60.0% (95%CI: 26.2-87.8) and a specificity of 57.1% (95%CI: 34.0-78.2). Of the 31 patients, paramedics and stroke neurologist scores differed by 0-2 points in 42% of patients, 3-4 points in 39% patients, and greater than 4 points in 19% patients.

Conclusions:
In a single-center study, mNIHSS had moderate sensitivity for LVO. Paramedics were able to complete a stroke scale with high reliability.
Abstract TP313: Communication Center Guided Prehospital Stroke Assessment Has Sustained Ability to Identify Patients With Large Vessel Occlusion
Authors: Gropen Toby I , Gazi Melissa , Minor Michael , Fadairo Abimbola , Acker Joe
Published: January 2019

Introduction:
There is need for sustainable models of effective prehospital stroke triage.

Goal:
Prospectively validate communication center guided prehospital identification of stroke patients with large vessel occlusion (LVO).

Methods:
We trained Alabama Trauma Communication Center (ATCC) paramedics in the previously derived 6 point Emergency Medical Stroke Assessment (EMSA). ATCC staff guided Emergency Medical Service (EMS) responders in the Birmingham Regional Emergency Medical Services System (BREMSS), and paged-out a hospital prenotification that included specific EMSA items (gaze, facial droop, arm drift, leg drift, naming, and repetition). Ongoing quality improvement was designed to enable the ATCC staff to effectively guide EMS responders. We derived the sensitivity, specificity, negative likelihood ratio (LR-), positive likelihood ratio (LR+), and receiver operator characteristics area under the curve (AUC) and 95% confidence intervals (CI) of ATCC guided EMSA for predicting a discharge diagnosis of LVO for patients transported to the University of Alabama at Birmingham.

Results:
We enrolled 521 patients from September 2016 through February 2018. Patients who only responded to pain (n=29, 5.6%) or who were unresponsive (n=21, 4%) were excluded. Of 471 patients analyzed, 247(52%) had a discharge diagnosis of stroke, including 182 (74%) acute ischemic stroke, 36 (14%) intracerebral hemorrhage, and 29 (11%) transient ischemic attack. There were 45 (18%) stroke patients with proximal LVO, including 31 middle cerebral artery stem, 12 internal carotid artery, and 2 basilar artery. Overall, an EMSA score ≥ 4 had sensitivity = 75.6%, specificity = 62.2%, LR- = 0.39, and LR+ = 2.00 for proximal LVO. During the first 9 months of the study, the EMSA AUC = 0.61 (CI = 0.45 – 0.77) compared to an AUC = 0.74 (CI = 0.64 – 0.84) during the second 9 month period of the study.

Conclusions:
EMS stroke medical control based on communication center guided prehospital stroke assessment and ongoing quality improvement is feasible and results in sustained ability to identify patients with LVO. Further studies are needed to evaluate the impact of guided prehospital triage of patients with suspected LVO on health outcomes.