bluuebunny/crossref_metadata_2025 huggingface dataset:
Abstract WP230: Regional Variations in In-Hospital Mortality Among Patients Treated With Mechanical Thrombectomy in the United States
Authors: Girotra Tarun , Lekoubou Alain , Bishu Kinfe , Ovbiagele Bruce
Published: January 2019

Background:
There have been well described regional variations in treatment offered for acute ischemic strokes (AIS) but there is a paucity of data regarding such variations in outcomes in patients treated with mechanical thrombectomy (MT) in the US.

Objective:
To assess regional variations of in-hospital mortality among patients treated with MT for AIS in the US.

Methodology:
Nationwide Inpatient Sample database used to gather information on patients receiving MT for AIS from 4 US regions [Northeast (NE), Midwest (MW), South (S), & West (W)] from 2006 to 2014. Independent predictors of in-hospital mortality after stroke treated with MT were evaluated using multivariable logistic regression.

Results:
6049 patients received MT for AIS during the study period (NE 20%; MW 25%; S 31%; W 24%). No significant difference was noted in age, gender, and Charlson comorbidity index between the regions. Adjusted multivariable logistic regression analysis revealed odds ratio (OR) for in-hospital mortality of 0.72 (95% CI 0.54-0.97) in MW, 0.71 (95% CI 0.54-0.94) in W, and 0.85 (95% CI 0.65-1.12) in S compared to NE. Other factors associated with greater in-hospital mortality are males (female OR 0.84; 95% CI 0.72-0.99), older age [ORs for 45-64 y: 1.5 (95% CI 1.1-2.2); 65-84 y: 2.1 (95% CI 1.4-2.9); ≥85y: 2.9 (95% CI 1.9-4.5) (reference: <45 y)], weekend admissions (OR 1.13; 95% CI 1.11-1.55), and shorter LOS (OR 0.89 per 1 day increase in LOS; 95% CI 0.86-0.91). Patient’s income and ethnicity, hospital size, and academic status of the treating hospital were not associated with in-hospital mortality.

Conclusions:
In the United States, rates of in-hospital mortality were significantly lower in patients receiving MT in the MW and W compared to the NE, a difference not explained by demographics or comorbidities. The NE has greater population density and more traffic delays vs. other regions, which may prolong time to recanalization and negatively impact the outcome. Closer analysis of regional variations in time sensitive quality measures of acute stroke care and complication rates could help clarify such findings.
Abstract WP231: High Serum Homocysteine is a Risk of Future Stroke in Neurologically Normal Japanese Cohort
Authors: Mitaki Shingo , Oguro Hiroaki , Nagai Atsushi , Yamaguchi Shuhei
Published: January 2019

Introduction:
Homocysteine is reportedly involved with direct endothelial damage that seems to cause vascular damage. Considering the racial differences in homocysteine levels and the atherosclerotic process in cerebral arteries, the impact of risk factors on stroke are likely different from those in Caucasians, however, to date, there are no Japanese cohort studies on the relationship between homocysteine levels and incidence of stroke. Therefore, we aimed to clarify the relationship between serum homocysteine levels and stroke risk in neurologically normal Japanese cohort.

Materials and Methods:
From January 2000 to December 2016, a total of 4,552 Japanese subjects voluntarily participated in a health checkup. Among the 4,552 subjects, the final analysis included 412 subjects (203 men and 209 women) aged 32-89 years (mean 65.1 ± 9.2) from whom we could obtain serum homocysteine levels and follow-up information with a mean interval of 7.6 years after the initial examination. The follow-up information about health conditions was obtained by annual mail inquiries. Homocysteine levels were categorized in quartiles of the baseline distribution, and the associations between the homocysteine level and demographics, vascular risk factors, asymptomatic lesions on MRI, cognitive functions, and incidence rates for stroke and all-cause of death were investigated.

Results:
After adjustment for the traditional cardiovascular risk factors, a higher homocysteine level was associated with silent brain infarctions [odds ratio for the highest vs the lowest quartile of homocysteine, 3.71 (95% confidence interval (CI): 1.04-13.2, P=0.04)] at baseline evaluation. During follow-up, there were 13 documented cases of stroke and 16 all-cause cases of deaths. In a Cox hazard model, homocysteine levels were significantly associated with incidence of stroke when fully adjusted for traditional cardiovascular risk factors. Participants with a higher homocysteine level had a 10.7-fold increased risk for stroke (95% CI, 1.09-104.1, P=0.04); however, there was no association between homocysteine levels and all-cause death.

Conclusions:
High serum homocysteine level was significantly associated with silent brain infarctions and incidence of stroke in Japanese.
Abstract WP232: Targeted Mass Stroke Education Improves Knowledge of Stroke Signs in Georgia
Authors: Davis Victoria N , Ido Moges , Evans Andrew , Bayakly Rana , Drenzek Cherie
Published: January 2019

Introduction:
Acute stroke patients must be transported to stroke-ready facilities swiftly for better patient outcomes. Public knowledge of stroke signs and the need to call emergency medical services (EMS) is critical to ensure that stroke patients get to hospital timely. This study assesses the impact of a targeted stroke awareness campaign launched by the Georgia Department of Public Health (DPH) in 2017.

Method:
From May to September 2017, the Georgia DPH launched a multipronged public stroke education campaign involving public service announcements, posters on mass transport systems, billboards on highways, and digital displays at sport events. The campaign targeted African-Americans because of their higher risk for stroke. Four questions about stroke signs (facial droop, arm weakness and slurred speech) and the importance of calling 911 were added to the 2017 Georgia Behavioral Risk Factor Surveillance System (BRFSS) survey. The pre and post-campaign levels of knowledge of stroke signs, as determined by answers to BRFSS questions, were compared among different race groups using SAS-callable SUDDAN software and applying logistic regressions for model adjusted prevalence differences.

Results:
In general, a 3.8% to a 5.5% improvement in knowledge was documented for each sign of stroke. The proportion of adult Georgians who knew all three signs of stroke included in the campaign and the importance of calling 911 increased from 49.9% pre-campaign to 56.0% post-campaign. However, the improvement was significant and more pronounced among African Americans (16%, SE=7%) than among Whites (1%, SE=4%), and Hispanics (3%, SE=10%) controlling for other potential predictors. Moreover, relatively fewer Hispanics (29%; 95%CI: 19%, 41%) provided the correct answers to the four questions than African-Americans (58%; 95%CI: 51%, 64%) and Whites (62%, 95%CI: 58%, 67%) post-campaign.

Conclusion:
The Georgia DPH’s targeted mass educational campaign was effective in improving the knowledge of stroke signs among the public and the need to call EMS. The Department must continue its education effort to improve public’s knowledge with emphasis on reaching the Hispanic population.
Abstract WP237: Risk Factors for Aneurysmal Subarachnoid Hemorrhage in Women: Systematic Review and Meta-Analysis
Authors: Rehman Sabah , Sahle Berhe , Chandra Ronil V , Thrift Amanda G , Callisaya Michele , Dwyer Mitchell , Breslin Monique , Phan Hoang T , Otahal Petr , Gall Seana
Published: January 2019

Background:
Aneurysmal subarachnoid hemorrhage (aSAH) affects women more than men, unlike other stroke types. We completed a systematic review and meta-analysis of risk factors associated with the occurrence of aSAH in women.

Methods:
A systematic search was conducted using the Pubmed, Scopus, Embase, and Medline databases from inception to November 2017 to identify studies that included aSAH risk factors among women only or mentioned female sex as a risk factor. The risk factors were assessed using meta-analysis if reported by at least two studies.

Results:
Fourteen studies (10 case-control; 4 cohort) were included. Female sex was associated with higher odds or risk of aSAH in pooled estimates of cohort studies (HR
adjusted
1.90, 95% CI 1.47-2.46) but not in case-control studies (OR
adjusted
1.44, 95% CI 0.83-2.52). Menarche at an early age (age <12 years HR
crude
1.15 [95% CI 0.52-2.55], age <13 years OR
adjusted
3.24 [95% CI 1.25-4.03]), pregnancy at ≥26 years (OR
adjusted
1.78 [95% CI 1.13-2.80]), use of contraceptive pills (RR
crude
range, 5.3-6.5), nulligravidity (OR
adjusted
4.23 [95% CI 1.05-7.56]), aSAH predilection area (RR
crude
1.81) and being divorced (RR
crude
1.89) increased the risk for aSAH in women. Parity moderately decreased the risk for aSAH (parity >3 HR
crude
1.21 [95% CI 0.68-2.14], parity=2 OR
adjusted
0.87 [95% CI 0.64-1.19], parity ≥5, OR
adjusted
0.25 [95% CI 0.03-1.89]).

Conclusion:
A number of risk factors, primarily related to reproductive hormones, for aSAH were identified in women. These could be potential causes of higher incidence of aSAH in women compared to men. There is a need for further research focused on aSAH in order to explore the association of these risk factors with aSAH in women.
Abstract WP239: Caregiver Burden Among Informal Caregivers of Stroke Survivors
Authors: Achilike Saviour , Sanner Jennifer E , Okpala Munachi , Payen Samuel , Baldridge Lyric , Okpala Nnedinma , Sharrief Anjail , Savitz Sean
Published: January 2019

Background and Purpose:
Caregiver burden is commonly encountered in chronic disease management. Caregiver burden among informal caregivers of stroke survivors has potential to impact patient outcomes. We sought to assess the degree of caregiver burden and related factors among informal caregivers of patients followed in our Stroke Transitions Education and Prevention (STEP) clinic.

Methods:
We surveyed informal caregivers accompanying stroke patients to our STEP clinic visits within 2 years of ischemic or hemorrhagic stroke occurrence. Assessments included a caregiver demographic questionnaire, Zarit caregiver burden scale, patient health questionnaire-9 (PHQ-9, depression), Barthel index (BI -stroke survivor). Zarit score was dichotomized as no/minimal burden vs mild/moderate/severe burden. Univariate and multivariate analysis were conducted using logistic regression.

Results:
Among 71 surveys obtained, 69% of informal caregivers were women, despite a similar gender distribution of stroke survivors (54% women). While 49% of caregivers reported some degree of caregiver burden, 34% were classified as moderate-severe or severe. Caregiver burden was strongly associated with stroke survivor physical disability; odds of moderate or worse caregiver burden was 4.5 times higher (95% CI 1.52, 16.1) with BI < 75 compared to = 75. Additionally, odds of moderate-severe depression, as defined by PHQ-9 > 9, were 10 times higher (95% CI 2.06, 48.9).

Conclusions:
High levels of caregiver burden exist among informal caregivers of stroke survivors, and burden is associated with stroke survivor physical disability. Caregiver burden was associated with significantly greater odds of depression. Findings suggest the need for studies focused on characterization of informal caregiver needs and interventions to address the challenges they face.
Abstract WP240: Community Engagement for Early Recognition and Immediate Action in Stroke (CEERIAS): Exploring Stroke Knowledge, Self-Efficacy, and Trust in the Healthcare System in Chicago
Authors: Song Sarah Y , Kwon Soyang , Wymore Erin , Kandula Namratha , Brown Jen , Eisenstein Amy , Richards Christopher T , Mason Maryann , Beckstrom Heather , Jones Peggy , Washington Knitasha , Aggarwal Neelum , Prabhakaran Shyam
Published: January 2019

Introduction:
In a segregated city like Chicago with distinct neighborhood characteristics, a discrepancy between neighborhoods in stroke knowledge, self-efficacy, and trust in the medical system could impact stroke outcomes.

Methods:
As part of a study which implemented a culturally-tailored stroke preparedness intervention targeting South (S) Side Chicago communities, individuals attending community health events were recruited in S neighborhoods and North (N) Side neighborhoods pre- and one-year post-intervention to assess stroke knowledge, self-efficacy, and trust. Independent stand-alone pre- and post-sample cohorts were purposefully recruited to match demographics. Survey outcomes included knowledge (assessed via Stroke Action Test, STAT), self-efficacy (Likert scale), trust (Health Care Trust Survey), and stress (Likert). Zip codes divided subjects into S/N neighborhoods. Two-sample t-tests compared cohorts, and interactions between race/ethnicity-time and neighborhood-time were tested, with multivariable linear regression when statistically (p<0.05) significant.

Results:
We recruited 364 subjects pre-intervention (S=199, N=165) and 363 subjects post-intervention (S=198, N=165) who were well-matched in race/ethnicity, sex, and education, though the post-group was slightly younger (p=0.04). Unadjusted analysis revealed increases post-intervention in stroke knowledge (p=0.07), self-efficacy (p<0.0001), trust (p<0.0001), and stress scores (p<0.0001). After adjusting for race/ethnicity, gender, and age, the N post-group had greater gains in knowledge (N: 4.0, p=0.02 vs. S: 0.7, p=0.69), self-efficacy (N: 2.3, p<0.0001 vs. S: 0.7, p<0.0001), trust (N: 0.8, p<0.0001 vs. S: -0.1, p=0.20) and stress (N: -0.3, p<0.0001 vs. S: -0.1, p=0.04).

Conclusions:
The observed gains in stroke knowledge, self-efficacy, trust, and stress, greater in the North Side of Chicago, could signal overall improved public health messaging around stroke recognition and treatment, but could also point to socioeconomic factors that may have disproportionately benefited North Side residents. Further focused research to understand neighborhood factors which influence stroke awareness and action is necessary.
Abstract WP241: 30-Day Readmission for Mechanical Thrombectomy Among Patients With Ischemic Stroke
Authors: Vela-Duarte Daniel , Lekoubou Alain , Bishu Kinfe G , Ovbiagele Bruce
Published: January 2019

Background:
Mechanical thrombectomy (MT) is standard of care for acute ischemic stroke (AIS) due to large vessel occlusion of the anterior circulation, and is proven to improve clinical outcomes; however, little is known about short-term readmission rates and associated risk factors.

Methods:
The Nationwide Readmissions Database data between January and November 2014 was used to identify patients older than 18 years who underwent MT for AIS across 22 participating states in the United States. An adjusted multivariable logistic regression model was constructed to explore associations between demographic and socioeconomic characteristics. An index hospitalization was identified with primary diagnosis of ICD-9 codes 433X1, 434.X1 and 436. A procedure code for mechanical thrombectomy was identified by 39.74.

Results:
A total of 502,604 suffered AIS in 2014, 4,899 (0.97%) individuals underwent MT equally across genders, with 2385 (48.7%) women, 2514 (51.3%)[BK1] [DV2] men mostly between 65 and 84 years old. Over 60% corresponded to Medicare with 91.2% performed at large metropolitan hospitals. Males were readmitted more frequently than women within 30 days following AIS (3.35%, 2.75% respectively, p=0.0000) and only 73 (1.5%) patients were readmitted following MT. No differences in 30-day readmission were observed across median household income, admission day of the week or hospital size. Patients who underwent MT (aOR 0.62, 0.40-0.96), female sex (aOR 0.86, 0.81-0.91), hospitalization length >7 days (aOR 0.82, 0.72-0.92) were associated with lower risk of readmission at 30 days, while age 65-84 years (aOR 1.60, 1.35-1.90) represented a higher risk of readmission among adults with AIS.

Conclusions:
In the United States in 2014, the readmission rate after MT for AIS of anterior circulation is 1.5% at 30 days. Older age was associated with a 60% increase in adjusted odds of readmission among adults with AIS. MT has been demonstrated to be safe and effective, however; the study dataset is limited to practices prior to recent landmark trials. We speculate that the rate of readmission will tend to decrease from 2015 onward due to better patient selection and lower complication rates.
Abstract WP244: Sex Differences in the Development of Cardiovascular Disease in Young Adults
Authors: Leppert Michelle H , Cotton Eleanor , Weitzencamp David , Campbell Jonathan , Ho Michael , Burke James , Poisson Sharon
Published: January 2019

Background:
While there have been dramatic declines in the incidence of cardiovascular diseases in older adults, the incidence of strokes and acute myocardial infarctions (AMI) in young adults are as high as ever. The goal of this study was to better understand sex differences in the incidence of stroke and AMI in young adults.

Methods:
A 10% random sample of all enrollees from a commercial claims database between 2001-2014 was used. Enrollees between 15 to 45 years old with claims for first ever stroke or AMI hospitalizations identified by ICD-9 code were included. Logistic regression was used to quantify incidence over time, adjusting for age groups and sex, also allowing for sex and year interaction (so women and men can have trends in opposite directions).

Results:
Among 3,717,422 young adults, there were 3357 incident stroke and 2986 incident AMI hospitalizations. The average age based on first year of enrollment was 28.6 with a mean 3.6 years of follow-up. There were 52.0% women overall. Women were more likely than men to be admitted for stroke (55.2% vs. 44.8%; p=0.0003) but less likely to be admitted for AMI (30.7% vs. 69.3%; p<0.0001). In the logistic model for trend, there was a slight but significant increase in stroke incidence overtime (OR 1.014 95% CI 1-1.027), but not in AMI (OR 1.011 95%CI 0.992-1.03). There is a 2.8 fold increased in the odds of AMI in men (95%CI 2.343-3.305) and a 0.912 decrease in the odds of stroke in men which was not significant (95% CI 0.783-1.062). The incidence of AMI in men declined overtime (OR 0.984 95%CI 0.961-1.006) but did not reach significance (figure).

Conclusions:
In the young adult population, AMI is more common in men and stroke is more common in women. The explanation for this difference is unclear but suggests there may be different etiologies of stroke and AMI in young adults. Further research could help to better define the varying role of atherosclerotic risk factors in young adults with stroke as compared with AMI.
Abstract WP247: Racial Disparities in Stroke Risk Among Older Adults in the Southern Community Cohort Study
Authors: Jimenez Monik C , Blot William , Manson JoAnn , Cook Nancy , Rexrode Kathryn
Published: January 2019

Introduction:
Racial disparities in stroke among older adults have been inconsistently reported, with sparse data for low-income adults. We examined racial disparities in stroke among low-income older adults and potential modification by age and sex.

Methods:
Participants were self-identified black and white adults in the Southern Community Cohort Study, a cohort of largely low-income adults from the southeastern US. Analyses were restricted to Medicare beneficiaries aged
>
65 years and free of stroke at baseline (2002-2009). Covariates were self-reported at baseline with follow-up through 2014 (mean=8
+
3 years). Incident fatal and non-fatal total, ischemic and hemorrhagic strokes were identified by validated algorithms using hospital discharge codes from Medicare linkage (ICD-9: 430-431, 433.x1, 434.x1, 436). Hazard ratios (HR) and 95% confidence intervals (CI) were estimated with Cox models.

Results:
Among 6,228 participants, 752 total strokes were observed (incidence rate=152 per 10,000 person-years). The mean age was 70
+
4 years, 66% were female and 59% were black. Compared to whites, blacks had a 65% significantly higher age-adjusted risk of total stroke (Table). In multivariable analysis, a >20% racial disparity persisted. Excess risk was largely attributable to a higher prevalence of risk factors (e.g. hypertension, obesity) that may be in the causal pathway. Racial disparities in total stroke were consistent across age groups and sex in minimally adjusted models. In fully adjusted models, racial disparities were significant only among men (HR=1.35, 95% CI:1.01-1.80) and those aged
>
75 years (HR=1.52, 95% CI: 1.18-1.96).

Conclusions:
In this low-income population with a high incidence of stroke, racial disparities in stroke persisted among older adults, even after controlling for established risk factors. More research is needed to examine how stroke prevention interventions can be tailored to meet the needs of low-income older adults.
Abstract WP248: Cortical Microinfarcts on 3T MRI in Patients With Carotid Artery Stenosis
Authors: Takasugi Junji , Miwa Kaori , Watanabe Yoshiyuki , Okazaki Shuhei , Todo Kenichi , Sasaki Tsutomu , Mochizuki Hideki
Published: January 2019

Background and Purpose:
There is still uncertainty about the underlying mechanism of cortical microinfarcts in patients with carotid artery stenosis. We assessed the association between cortical microinfarcts (CMIs) on 3T MRI and imaging features of carotid and brain MRI.

Methods:
Eighty-nine patients with >50% carotid artery stenosis on carotid ultrasound were prospectively included, and underwent both carotid and brain MRI. CMIs were rated according to pre-determined criteria based on double inversion recovery and 3D FLAIR images.

Results:
We identified 69 CMIs in 26 (29%) patients. Multivariate-adjusted models showed CMIs were associated with intraplaque hemorrhage, and cortical infarct but not with severe stenosis (>70%) or markers of small vessel disease (SVD) such as white matter hyperintensities and cerebral microbleeds. Among 81 patients with unilateral carotid artery stenosis, 18 patients (22%) had 52 CMIs in ipsilateral hemisphere, while 6 patients (6%) had 9 CMIs in contralateral hemisphere. The number of CMIs were significantly higher in the ipsilateral side than in the contralateral side (
P
= 0.005).

Conclusions:
CMIs were associated with intraplaque hemorrhage, cortical infarct, and carotid artery stenosis. These findings suggest artery-to-artery emboli might be the underlying cause of CMIs in patients with carotid artery stenosis.
Abstract WP249: Illicit Drug Use and Cerebral Microbleeds in Stroke and Transient Ischemic Attack Patients
Authors: Petrie Benjamin , Lau Helena , Cajiga-Pena Fe Maria , Abbas Saleh , Finn Brandon , Dam Katie , Cervantes-Arslanian Anna , Nguyen Thanh N , Aparicio Hugo , Greer David , Romero Jose R
Published: January 2019

Background:
Cerebral microbleeds (CMB) signal cerebral small vessel disease and are associated with ischemic stroke (IS) incidence, recurrence, and complications. While illicit drug use (IDU) is associated with cerebral small vessel disease, the association between CMB and IDU is understudied. We sought to delineate differences in vascular risk factors between IDU and CMB and determine the effect of this relationship on outcomes in IS/transient ischemic attack (TIA) patients.

Methods:
We included 2001 consecutive IS and TIA patients (years 2009-2018) with a readable T2*gradient-echo MRI sequence. CMB rating followed standardized guidelines and CMB were grouped topographically into lobar, deep or infratentorial. IDU data (history and/or urine toxicology) was available for 1746 patients. The adverse composite outcome included pneumonia, urinary tract infection, deep venous thrombosis or death during hospitalization. Good functional outcome was defined as modified Rankin scale score < 3 and ambulatory on discharge. Univariate analysis was used to assess vascular risk factors and multivariable logistic regression was used to characterize the IDU/CMB relationship on outcomes.

Results:
We observed IDU in 13.8 % (n=241), and CMB in 32.9% (n=575, 53.8% lobar, 27.3% deep and 18.8% infratentorial). Patients with IDU and at least one CMB were older (53.6±10.5 vs. 56.9±11.5, p=0.04), had a lower BMI (28.1±5.9 vs. 26.6±4.4, p=0.04), and were more likely to have had a previous IS/TIA (25.1% vs. 41.9%, p=0.01). IDU trended higher for those with severe CMB (10+) compared with those without CMB and 1-9 CMB (25% [n=9] vs 14.3% [n=1171] and 12.1% [n=65] respectively; p=0.07) without individual drug deviations from this pattern. Adverse and good functional outcomes were observed in 177 and 905 total patients, respectively. No significant interaction was observed between IDU and CMB with either adverse or functional composite outcomes.

Conclusion:
IDU prevalence was high in our urban study population, and showed a borderline association with increasing CMB burden. Patients with CMB and IDU history were older and more likely to have had a previous IS/TIA. Further studies are required to clarify the clinical consequences related to the relationship between IDU and CMB.
Abstract WP25: Trends in the Use of Intravenous tPA and Mechanical Thrombectomy [MT] Among Elderly Medicare Beneficiaries Hospitalized for Acute Ischemic Stroke
Authors: Vaughan Sarrazin Mary S , Leira Enrique
Published: January 2019

Objective:
Early treatment with intravenous tissue plasminogen activator (tPA) followed by mechanical thrombectomy [MT] is the new standard of care for stroke patients with proximal arterial occlusion. We examined trends in the use of tPA and MT among black and white Medicare beneficiaries with stroke.

Methods:
We used de-identified data for Humana Medicare beneficiaries age >=65 to identify admissions for stroke during January 2009-March 2017 with primary diagnosis of ischemic stroke. Outcomes included IV tPA and MT identified by CPT, ICD-9, and ICD-10 procedure codes. Additional patient characteristics included demographics, comorbid conditions based on diagnosis codes prior to the stroke, and medication use from pharmacy claims. Logistic regression was used to evaluate the trends and racial differences in the use of IV tPA and MT while controlling for patient characteristics.

Results:
We identified 12,641 and 81,100 stroke admissions for black and white patients, respectively. Blacks were younger and more likely to have previous stroke, while white patients were more likely to have atrial fibrillation and use anticoagulants. Overall, 7558 (8.1%) received tPA during or within 1 day of stroke admission and 1533 (1.6%) underwent MT. The proportion of admissions receiving tPA increased from 5.3% in 2009-2010 to 9.9% in 2015-2016 among white patients, and from 5.7% to 9.9% among black patients. The proportion who underwent MT increased from 0.6% to 2.4% among whites, and from 0.5% to 2.5% among black patients. In multivariable logistic regression, the relative increase in tPA use over the observation period was 1.3 times greater for white compared to black patients (Odds Ratio [OR] for 2015-2016 relative to 2009-2010 = 2.01 [p<.001] for white patients and 1.55 [p<.001] for black patients). In contrast, the relative increase in MT use was nearly 2 times greater for black compared to white patients (OR for 2015-2016 relative to 2009-2010 = 3.90 [p<.001] for black patients and 2.01 [p<.001] for white patients).

Conclusions:
We did not find evidence of racial differences in the use of tPA or MT among black and white patients with acute ischemic stroke. Overall there was a dramatic increase in the use of recommended therapies over the 9-year observation period.
Abstract WP252: A Mendelian Randomization Study of Plasma Homocysteine and Ischemic Stroke in a Han Chinese Population
Authors: Kelly Tanika , Zhang Yonghong , Li Changwei , Wang Aili , Xu Tan , Sun Xiao , Shi Mengyao , Bu Xiaoqing , Chen Jing , He Jiang
Published: January 2019

Introduction:
Observational studies identified plasma homocysteine as a risk factor for ischemic stroke, but randomized controlled trials of folate supplementation reported inconsistent findings. The
MTHFR
gene encodes an enzyme critical for homocysteine metabolism and can serve as an unconfounded proxy for plasma homocysteine levels. We examined the association between the
MTHFR
gene and ischemic stroke among 11,753 Chinese participants.

Methods:
The discovery stage included 999 ischemic stroke cases and 1,001 controls with no history of atherosclerotic disease. The
MTHFR
gene was sequenced using the SOLiD 4hq platform. Variants with minor allele count (MAC) >10 were each tested for association with stroke using logistic regression models. Interactions between significant variants and alcohol drinking on stroke were also tested. Aggregate analysis of rare variants (MAC <20) used the sequence kernel association test. Variants achieving P<1х10
-4
were tested for replication among 4,724 ischemic stroke cases and 5,029 controls from the China Stroke Project.

Results:
An association between
MTHFR
rs1801133, a missense variant known to reduce enzyme activity and increase plasma homocysteine level, and ischemic stroke was identified in discovery, replication and joint analyses (P=2.10х10
-8
, 2.65х10
-11
, and 6.93х10
-17
, respectively). Each copy of the rs1801133 risk allele conferred respective odds ratios (95% CI) of 1.44 (1.27, 1.64), 1.21 (1.15, 1.28), and 1.25 (1.18, 1.31). This variant also interacted with alcohol intake on stroke risk (P for interaction=7.82х10
-9
, 1.86х10
-10
, and 1.46х10
-18
, respectively). Odds ratios (95% CI) of stroke associated with the risk allele were 1.66 (1.40, 1.96), 1.26 (1.18, 1.36), and 1.32 (1.23, 1.40) in non-drinkers and 1.17 (0.92, 1.49), 1.12 (1.01, 1.23), and 1.12 (1.03, 1.23) among alcohol drinkers in discovery, replication and joint analyses, respectively. No additional variants were identified.

Conclusions:
This is the first large scale genomic study to implicate the etiologic relevance of plasma homocysteine in ischemic stroke. An attenuating effect of alcohol intake on this relation was also observed.
Abstract WP253: Cystatin C and the Risk of Cardioembolic Stroke in Patients Without Chronic Kidney Disease
Authors: Lee Eung-joon , Jeong Han-yeong , Mo Heejung , Lee Chan-hyuk , Kang Min Kyoung , Kim Tae Jung , Ko Sang-bae , Yoon Byung-woo
Published: January 2019

Background and Objectives:
Atrial fibrillation (AF) is well-established risk factor for cardioembolic stroke. Epidemiological evidence indicates that there is increased risk of AF with chronic kidney disease (CKD) and impaired renal function. Cystatin C (Cys-C) is now considered as a specific marker for detection of renal impairment. However, there are no data about the potential association of Cys-C with AF and cardioembolic stroke in the subjects without evident CKD. We investigated whether serum Cys-C level is associated with development of cardioembolic stroke in patients with AF.

Methods:
Consecutive data were collected retrospectively at the Seoul National University Hospital (SNUH). Patients with ischemic stroke with subtypes of large artery atherosclerosis, small vessel occlusion and cardioembolism who admitted at the SNUH between November 2014 and November 2017 were screened. We excluded the patient who have a history of secondary hypertension, CKD (estimated glomerular filtration rate < 60 mL/min/1.73 m
2
), valvular heart disease, congenital heart disease, dilated or hypertrophy cardiomyopathy and thyroid disease.

Results:
Among the total 627 patients, 61.8% were male, with a mean age of 67.9 years. Compared to the other stroke mechanisms, a stepwise logistic regression analysis showed that AF was independently associated with size of left atrium (OR, 1.196, 95% CI: 1.160-1.266), initial stroke severity (NIH Stroke Scale) (OR, 1.126, 95% CI: 1.083-1.189), and Cys-C (OR, 2.472, 95% CI: 1.255-15.129), but not with eGFR (OR 0.993, 95% CI: 0.977-1.009).

Conclusion:
Cys-C is a superior predictor for cardioembolic stroke due to AF in patients without evident CKD.
Abstract WP254: Predictors of Atrial Fibrillation Detection by Mobile Cardiac Output Telemetry After Hospital Discharge for Acute Ischemic Stroke
Authors: Sharma Richa , Sanborn Danita , Silverman Scott , Schwamm Lee
Published: January 2019

Background:
Patients with cryptogenic stroke without atrial fibrillation (AF) detected in the hospital often undergo 30-day mobile cardiac outpatient telemetry (MCOT) to increase the AF detection rate. We sought to determine the clinical and transthoracic echocardiogram (TTE) characteristics associated with AF detection by MCOT.

Methods:
We analyzed a cohort of admissions from 2005 to 2016 with an acute ischemic stroke diagnosis, an inpatient TTE, and an MCOT performed upon discharge. Each admission was treated as a unique observation. Cases with subsequent AF vs. no AF on MCOT were compared by Chi-squared tests if variables were categorical and t-tests if continuous. A multivariable stepwise logistic regression model was created to determine the predictors of AF detection as a function of variables which were significant in univariate analysis and not significantly collinear.

Results:
Of the 4,880 inpatient hospitalizations for acute ischemic stroke with an TTE performed during admission, there were 283 cases which underwent MCOT (10.4 cases/year in 2005-2014, 90 cases/year in 2015-2016). There were 23 (8.10%) cases of AF on MCOT, and they were more likely to be older, white, admitted earlier during the study, and have larger left atrial anterior-posterior and medial-lateral dimensions (Table). A multivariable model demonstrated that age greater than the median of 66 yr (OR 3.25, 1.21-8.74) and left atrial anterior-posterior dimension greater than the median of 40cm (OR 5.86, 2.38-14. 43) were strong predictors of AF detection by MCOT (c-statistic 0.78).

Conclusions:
We observed low rates of AF on 30-day MCOT post-discharge. Left atrial anatomic dimension is predictive of a higher rate of early AF detection after adjusting for age. This TTE feature, coupled with clinical information, may improve patient selection for MCOTs and potentially avoid the need for more expensive implantable loop monitors in those for whom MOCT does not yield an answer.
Abstract WP255: The Role of Echocardiography and ECG in Stroke Patients
Authors: Wasser Katrin , Weber-Krüger Mark , Jürries Falko , Liman Jan , Hamann Gerhard F , Kermer Pawel , Seegers Joachim , Mende Meinhard , Gröschel Klaus , Wachter Rolf
Published: January 2019

Background:
The cardiac diagnostic workup of stroke patients, especially the value of echocardiography and prolonged and enhanced Holter-ECG monitoring (EPM), is still a matter of debate. We aimed to analyse the impact of pathologies detected by echocardiography and ECG monitoring on therapeutic decisions and prognosis.

Methods:
Find-AF
RANDOMISED
was a prospective multicenter study which randomised 398 acute ischemic stroke patients ≥ 60 years to EPM or usual stroke unit care. Therapeutic consequences of echocardiography and routine Holter-ECG or EPM, respectively, were compared and one-year mortality was calculated.

Results:
50.3% received EPM and 49.7% routine ECG monitoring. 82.9 % underwent transthoracic echocardiography (TTE), 38.9 % transesophageal echocardiography (TEE) and 25.6 % both procedures. 14/90 TEE pathologies and 1/89 TTE pathology led to a change in therapy, resulting in a number needed to change decision (NNCD) of 12 and 334, respectively. In comparison, EPM found atrial fibrillation (AF) in 27 of 200 patients, and routine ECG monitoring in twelve of 198 patients, leading to therapeutic changes in all patients (NNCD 8 and 17, respectively). We found a trend towards a higher one-year mortality in patients with pathologic echocardiographic findings (p = 0.093).

Conclusions:
Most changes in therapeutic decisions were caused by EPM, which should therefore play a more prominent role in future guidelines. Echocardiography identifies a patient group at high cardiovascular risk, but rarely result in therapeutic changes. Whether this patient group requires further cardiovascular workup remains unknown. This should be further investigated by interdisciplinary neurocardiologic teams and in appropriate future trials.
Abstract WP257: Occurrence and Imaging Patterns of Recurrent Strokes iIn a Cohort of Cryptogenic Stroke Patients on Long Term Cardiac Monitoring
Authors: Sethi Pramod , biby sharon , xu jindong
Published: January 2019

Introduction:
Cryptogenic strokes account for one third of all strokes. Atrial fibrillation has been described as a leading cause in this population but occurrence of atrial fibrillation and imaging charecteristics amongst recurrent strokes in this population have not been characterized well.

Methods:
We reviewed electronic medical charts of a cohort of cryptogenic patients from February 2014 to September 2017 who underwent REVEAL LINQ insertable cardiac monitor. All patients met ESUS( Embolic Stroke of Unknown Source) criteria prior to implantation and were enrolled in the atrial fibrillation clinic with structured remote follow-up. All newly diagnosed atrial fibrillation was confirmed by electrophysiologists and recurrent strokes were confirmed by vascular neurologist after reviewing presentation, electronic medical record and brain imaging studies.

Results:
Atrial fibrillation was detected in 108 out of a total of 429 patients ( 25%) . Time to atrial fibrillation detection was average 79.8 days with a range of 13-430 days . All but one patient were started on anticoagulation. Within the entire cohort 55 patients had recurrent strokes with 7 of them having more than 1 recurrence.. 15 recurrent strokes occurred in patients in whom atrial fibrillation was detected during monitoring and 40 in patients without atrial fibrillation detected . Imaging pattern of recurrent strokes in patients with atrial fibrillation was cortical in 81.8% with 10 patients showing multiple infarcts and subcortical in 18.2% patients with one showing multiple infarcts. Strokes in patients without atrial fibrillation were cortical in location in 60% with 10 being multiple and subcortical in 40% with 3 patient having multiple infarcts.4 patients who did not have atrial fibrillation had more than 1 recurrent stroke and 3 patients who were detected to have atrial fibrillation had more than 1 recurrent stroke Conclusion majority of recurrent strokes in cryptogenic population did not have atrial fibrillation( 72.7%) Incidence of recurrent stroke was similar in patients with atrial fibrillation (13.8%) detected versus (12.4% %)not detected group . Imaging patterns showed more cortical strokes in A. fib patients ( 80%) and more subcortical strokes in patients without A. fib( 40%)
Abstract WP258: Is it Time to Stop Playing Hide-And-Seek With Atrial Fibrillation After Endovascular Treatment?
Authors: Cardona Pedro , Quesada Helena , Lara Blanca , Barranco Roger , Aja Lucia , Chirife Oscar , Paipa Andres , Mora Paloma , Aixut Sonia , Mora Paloma , Escrig Ana Maria
Published: January 2019

Background:
The etiology of stroke remains unknown over 25% of cases. Stroke with Large Vessel Occlusion (LVO) treated with endovascular treatment (EVT) and complete recanalization are a good group to analyze efficiency of diagnosis studies. After hospitalization the percentage and clinical impact of hidden atrial fibrillation (AF) diagnosis in embolic strokes of unknown source are uncertain.

Methods:
We reviewed patients treated with EVT from 2010 to 2016. We evaluated percentage of cases with new clinical diagnosis of atrial fibrillation during long-term follow-up in several etiologic subgroups. We analyze several epidemiologic variables, functional recovery and other relevant pathologies.

Results:
A total of 514 patients with complete cardiac diagnosis tests treated with EVT were analyzed over 3,9 years of follow-up. The etiology of stroke was unknown in 123 patients (23,9%). During follow-up were diagnosed 8% of patients with new atrial fibrillation/flutter in unknown etiology subgroup (3% in atherothrombotic and none in unusual subgroup). Half of them presented minor cardiologic symptoms but none of them had presented a new stroke. Variables significant associated to new finding of AF were >6 supraventricular extrasystoles or tachycardia in 24Holter test and severe auricular dilatation evaluated by means echocardiography during hospitalization (p:0.004). Only 2% patients were studied with long-term heart rhythm recorder. Other new diagnoses in follow-up of EVT were malignant neoplasm (7%) and delayed seizures (6%).

Conclusions:
The findings of atrial fibrillation in follow-up of patients treated with EVT with complete cardiac diagnosis tests are infrequent. The recurrence of stroke seems rare in follow-up, however we must select patients for catch atrial fibrillation by means long-term heart recorder systems according to signs of auricular impairment.
Abstract WP26: Factors Related to Acute Brain Swelling After Successful Recanalization With Mechanical Thrombectomy
Authors: Hamada Yuki , Tatsuno Kentaro , Takayuki Fukano , Tokuyama Yoshiaki , Takaishi Satoshi , Usuki Noriko , Takada Tatsuro , Yoshida Yasuyuki , Ono Hajime , Ueda Toshihiro
Published: January 2019

Background and Purpose:
We have experienced acute ischemic stroke patients who had poor outcome due to acute brain swelling after successful recanalization with mechanical thrombectomy. The aim of this study was to investigate factors related to acute brain swelling.

Methods:
The study included 89 patients who obtained successful recanalization (TICI 2b or 3) after mechanical thrombectomy for occlusions of the internal carotid artery (ICA) or middle cerebral artery from 2013 to June 2016. We classified by the distance of midline shift on FLAIR image including the lens nucleus and thalamus within 24 hours after treatment into 2 groups; more than 5 mm (Swelling group; the S group, n=16), and less than 5 mm (Non-Swelling; the N group, n=73). We compared demographic data, radiological characteristics, and outcomes between both groups. We also measured flow transit time (FTT) from intracranial artery to cortical vein with the use of automated software (syngo iflow, Siemens Healthcare, Germany).

Results:
Regarding mean time of onset-to-reperfusion time, medical history, treatment with IV-rtPA, there were no significant differences between both groups. Increase rate of the brain swelling area before and after treatment on FLAIR image was higher in the S group (20.9%) than in the N group (3.0%). The median FTT of the S group was 7.0 sec (IQR 4.5-7.5), the N group was 6.0 sec (5.2-6.5). The S group included more patients of ICA occlusion (80% vs. 46%, p=0.023), longer FTT (>7.0 sec, 60% vs. 13%, p<0.001), and lower DWI-ASPECTS (median 3 vs. 7, p<0.001). Parenchymal hematoma was equivalent in each group. Modified Rankin Scale score 0-2 at 90 days was significantly lower in the S group (0% vs. 37%, p=0.004). Logistic regression analysis showed FTT of more than 7 seconds was a significant independent predictor [OR 9.77 (2.13-54), p=0.003] of acute brain swelling.

Conclusion:
Important factors related to acute brain swelling after successful thrombectomy were ICA occlusion, lower DWI-ASPECTS, and longer FTT. Particularly FTT was a significant independent predictor of acute brain swelling.
Abstract WP260: Evaluation of Transcranial Doppler as a Screening Tool for High Embolic Risk Patent Foramen Ovale in Cryptogenic Stroke
Authors: Park Seongho , Oh Jin Kyung , Song Jae-Kwan , Kwon Boseong , Kim Jong S. , Kang Dong-Wha , Lee Ji-Sung , Kwon Sun U.
Published: January 2019

Background:
Identifying high embolic risk patent foramen ovale (PFO) from the innocent bystanders has become important in the evaluation of patients with cryptogenic stroke (CS) since the recent clinical trials showed the benefits of the closure of PFO on the prevention of recurrent stroke. Transesophageal echocardiography (TEE) is a gold standard to diagnose and evaluate the risk of PFO, but the tolerability and cooperation of handicapped stroke patients limit clinical applications. In this study, we aimed to evaluate the predictability of transcranial Doppler (TCD), a test deemed more feasible to stroke patients than TEE, in diagnosing high-risk PFO on TEE.

Methods:
We reviewed the data of 485 patients with CS who underwent TEE and TCD to evaluate PFO. To classify the shunts, we applied a 5-level visual classification for TCD either at rest or during Valsalva maneuver (VM): no occurrence of micro-embolic signals; grade I, 1-10 signals; grade II, 11-30 signals; grade III, 31-100; grade IV, 101-300; grade V, >300. High-risk PFO on TEE is defined as PFO with atrial septal aneurysm, hypermobility (phasic septal excursion into either atrium ≥10 mm), or PFO size (maximum separation of the septum primum from the secundum) ≥2 mm. Receiver operating characteristic (ROC) curve was used to determine the threshold value of TCD shunt grade for high-risk PFO which was demonstrated by TEE.

Results:
Concordant results between TCD and TEE appeared at 344 patients; present of shunt in 235 patients, and no-shunts in 109 patients. Patients with high risk PFO on TEE were detected in 133 among the 238 patients that were PFO positive on TEE. The proportion of high-risk PFO dramatically increased in accordance to the increase in TCD grade with VM. The best cut-off point of TCD grade with VM for detecting high risk shunt was grade III with an area under the curve (AUC) of 0.79, sensitivity of 73.1%, and specificity of 75.6% TCD with VM missed only 2 patients as having PFO among the 133 patients with high-risk PFO on TEE.

Conclusions:
This study showed that the findings of TCD on the diagnosis and evaluation of the risk of PFO were well correlated with those of TEE. Negative of shunt on TCD can exclude the possibility of high risk PFO; grade III or more on TCD suggests the presence of high risk PFO in patients with CS.
Abstract WP261: Role of Transcranial Doppler in a New Era of Patent Foramen Ovale Closure
Authors: Olivas Edgar , Lyden Patrick , Song Shlee , Dumitrascu Oana , Jackson Robert , Rinsky Brenda , Seth-Hunter Danielle , Cavallaro Michael , Schlick Konrad
Published: January 2019

Introduction:
Recent patent foramen ovale (PFO) closure trials have demonstrated efficacy in secondary stroke prevention. Transcranial Doppler (TCD) can reliably detect the presence of PFO, with sensitivity comparable to echocardiography. We sought to compare the sensitivity of TCD in detecting right to left shunt (RLS) using transesophageal echocardiogram (TEE) criteria as described in the CLOSE and REDUCE trials.

Methods:
We retrospectively reviewed all TCD studies at our institution who also had TEE studies. We excluded patients who had their PFO closed prior to one of these studies being performed. We classified the size of the PFO based on both REDUCE and CLOSE criteria (large was defined as greater than 25 microbubbles and greater than 30 microbubbles, respectively) and compared to the size based on the Spencer grade.

Results:
A total of 525 TCD bubble studies were performed at our institution from May 2013 to June 2018, 220 of which also underwent TEE. Using TEE as the gold standard, TCD detected 97.61% (41/42) of any moderate-large RLS and 100% (10/10) of any large RLS. The single patient who had a moderate RLS on TEE, but not TCD had a poor Valsalva during the TCD study. TCD detected 33 patients with RLS not detected on TEE [33% (33/100)], 33.3% of which were considered significant (Spencer grades 3-5).

Conclusion:
TCD is comparable to TEE in detecting moderate-to-large RLS based on REDUCE/CLOSE criteria. TCD detected an appreciable amount of RLS (a third of which were Spencer grades 3-5) not detected by TEE. Further study is needed to clarify the role of PFO closure in patients with significant RLS on TCD, but no RLS on TEE. TCD is a good alternative screening tool for RLS as compared with TEE methods from recent positive trials.