bluuebunny/crossref_metadata_2025 huggingface dataset:
Abstract WP179: Impact Of Different Cardiac Rhythm Monitoring Strategies On Secondary Stroke Prevention: A Systematic Review And Network Meta-analysis Of Randomized Controlled Clinical Trials
Authors: Katsanos Aristeidis , Triantafyllou Sokratis , Palaiodimou Lina , Mac Grory Brian , Deftereos Spyridon , Köhrmann Martin , Dilaveris Polychronis , Ricci Brittany A , Tsioufis Konstantinos , Cutting Shawna M , Magiorkinis Gkikas , Krogias Christos , Schellinger Peter D , Dardiotis Efthymios , Rodriguez Campello Ana , Cuadrado-Godia Elisa , Aguiar de Sousa Diana , Sharma Mukul A , GLADSTONE David J , Sanna Tommaso , Wachter Rolf , Furie Karen L , Alexandrov Andrei V , yaghi shadi , Tsivgoulis Georgios
Published: February 2022

Background and Purpose:
Prolonged cardiac rhythm monitoring can reveal a substantial proportion of ischemic stroke (IS) patients with atrial fibrillation (AF). We sought to evaluate the potential utility of available prolonged cardiac rhythm monitoring strategies with respect to secondary stroke prevention.

Methods:
We searched Medline and Scopus databases to identify randomized controlled clinical trials (RCTs) comparing AF detection, anticoagulation initiation and stroke recurrence rates in patients with history of recent IS or transient ischemic attack (TIA) receiving cardiac rhythm monitoring with implantable loop recorders (ILRs), 30-days external loop recorders or Holter monitors. We performed a network meta-analysis to combine direct and indirect evidence for any given pair of monitoring devices that were evaluated within a trial and reported effect estimates with risk ratios (RRs) and corresponding 95% confidence intervals (95%CIs).

Results:
We identified 5 RCTs including a total of 2202 patients (mean age 68 years, 40% women). In indirect analyses the likelihood of AF detection and anticoagulation initiation was higher for both ILR (RR=8.48, 95%CI: 3.41, 21.06; RR=3.29, 95%CI: 1.70-6.39) and external loop recorders (RR=3.06, 95%CI: 1.66, 5.61; RR=1.63, 95%CI: 1.03-2.58) compared to Holter devices. The probability of AF detection and anticoagulation initiation was lower for Holter and external loop recorders compared to ILR devices (RR=0.36, 95%CI: 0.15, 0.85 and RR=0.50, 95%CI: 0.25-0.98, respectively). No difference in the risk of stroke recurrence was found in the indirect comparisons of different cardiac rhythm monitoring strategies.

Conclusion:
The likelihood of AF detection and anticoagulation initiation after an ischemic stroke or TIA is higher with ILRs compared to both external loop recorders and Holter devices.
Abstract WP185: Not All Asians Are Alike: Disaggregation Of Stroke Mortality Among Asian Subgroups
Authors: Ganesh Ananya L , Chan Ching Yin Y , Kalva Swara R , Tripathi Osika , Dan Shozen , Palaniappan Latha , Srinivasan Malathi , Zhou Lily W , Vora Nirali
Published: February 2022

Background:
Stroke is the 5th leading cause of death in the US. National stroke mortality among Asian subgroups has never been reported. Our objective is to disaggregate national stroke mortality data among the largest Asian American groups by sex and characterize mortality trends across a 12-year period.

Methods:
We extracted National Vital Statistics System mortality data from 2006 to 2017 for 6 Asian subgroups and non-Hispanic Whites (NHWs). Stroke mortality was classified by ICD-10, including ischemic stroke (I630-699), intracerebral hemorrhage (I610-629), and subarachnoid hemorrhage (I601-609). 2006-2017 American Community Survey population data was extracted to calculate age-standardized mortality rates (AMRs) stratified by sex and race.

Results:
Participants included 2,593 Asian Indians, 7,585 Filipinos, 8,212 Chinese, 2,551 Koreans, 3,179 Vietnamese, 4,667 Japanese, and 781,966 NHWs. Mortality from hemorrhagic strokes exceeded ischemic stroke in groups except NHW (Figure 1A). From 2006-2017, deaths from ischemic stroke increased for all groups, with higher mortality in Filipino males compared to females (figure 1B). Deaths from subarachnoid hemorrhage increased only in the Vietnamese subgroup (figure 1D). A similar trend was observed for intracerebral hemorrhage in Vietnamese males (figure 1C).

Conclusion:
Disaggregation of US stroke mortality revealed important variations within the 6 largest Asian subgroups, including increased ischemic stroke mortality in all subgroups and increased hemorrhagic stroke mortality among Vietnamese. Considerations for this variation include differences in risk factor prevalence (cigarette smoking, obstructive sleep apnea) and social determinants of health. Future studies must collect disaggregated Asian subgroup data to provide tailored interventions to further reduce stroke mortality.

Figures:
See below
Abstract WP189: Ethnic And Racial Disparities In Prevalent Stroke Among Patients With Heart Failure
Authors: Ibeh Chinwe , Miller Eliza C , Marshall Randolph S , Willey Joshua Z
Published: February 2022

Background:
Ethnic and racial disparities in healthcare contribute to cardiovascular morbidity and mortality. Stroke is prevalent among patients with heart failure (HF) and is associated with worse long-term outcomes. We hypothesized that disparities in cardiovascular risk profiles contribute to differences in stroke prevalence among patients with HF.

Methods:
We performed a cross-sectional analysis of study participants age ≥ 60 in the biannual NHANES survey. Medical history and clinical variables were obtained from cycles 1999, 2001, 2011, and 2013. We created survey-weighted regression models to generate nationally representative estimates.

Results:
A total of 20,315 study participants representing 212,156,242 adults were included, 2.5% with prevalent HF. Compared to those without HF, participants with HF were more often of White race (72.8% vs 68.3%, P = 0.02) and less often of Hispanic ethnicity (10.4% vs 14.3%, P = 0.04). Stroke was 10 times more prevalent among individuals with HF (20% vs 2%, P <0.001). In the general population, after controlling for risk factors, Black race was associated with higher risk of stroke (OR: 1.44; 95% CI: 1.16-1.78). There was a significant interaction between HF and race/ethnicity on prevalent stroke (P = 0.05) such that the odds of stroke with HF was significantly higher in individuals of Hispanic ethnicity (OR: 11.9; 95% CI: 4.94-28.6), but similar in White and Black participants. In the assessment of differential risk factor burden among individuals with HF, only rates of diabetes differed between Hispanic and White individuals (36.2% vs 25.5%, p=0.04). There was no difference in mean values of LDL, BMI, systolic blood pressures or prevalent smoking.

Conclusion:
People of Hispanic ethnicity with HF have a higher prevalence of stroke which is not explained by vascular risk profiles and warrants further investigation.
Abstract WP192: Ischemic Stroke Mechanisms By Sex And Race Over Time In The Greater Cincinnati Northern Kentucky Stroke Study
Authors: Madsen Tracy , Khoury Jane C , De Los Rios La Rosa Felipe , Alwell Kathleen S , Woo Daniel , Mackey Jason , Mistry Eva , Ferioli Simona , Demel Stacie L , Coleman Elisheva R , Jasne Adam , Slavin Sabreena , Walsh Kyle B , Star Michael , Haverbusch Mary , Martini Sharyl R , Adeoye Opeolu M , Flaherty Matthew L , Khatri Pooja , Broderick Joseph P , Kissela Brett M , Kleindorfer Dawn O
Published: February 2022

Background:
Identifying the mechanism of acute ischemic stroke (AIS) is critical to determining secondary stroke prevention strategies. As past data conflict on sex and race differences in stroke mechanism, we aimed to describe stroke mechanisms by sex and race over time in a population-based study of AIS cases with a focus on strokes with unknown mechanism.

Methods:
We included physician adjudicated, hospital ascertained incident AIS among adults over five study periods (1993/4, 1999, 2005, 2010, 2015) from the Greater Cincinnati Northern Kentucky Stroke Study. Stroke mechanisms were adjudicated by trained study physicians and included: small vessel disease, cardioembolic, large artery disease, other, and unknown. The percentage of AIS cases in each of the 5 categories was reported by sex and race in each of our five 1-year study periods, and trends over time by subgroup were tested using the Cochran-Armitage trend test.

Results:
We included 8349 AIS over 5 study periods: 4693 (56%) were women, 1607 (19%) were Black, mean age was 70.5 (14.3). Over the 22-year time period, the proportion of strokes whose mechanism was ‘unknown’ decreased in women (46.1%, 1993/4 to 38.5%, 2015
,
p<0.0001), men (46.2%, 1993/4 to 33.9%, 2015, p<0.0001), Black (51.8%, 1993/4 to 40.7%, 2015, p=0.004), and White (45.0%, 1993/4 to 40.7%, 2015, p<0.0001) patients. The proportion of small vessel strokes increased over time in men, strokes of ‘other’ mechanisms increased in all subgroups, and cardioembolic strokes increased in women and White individuals only (Figure).

Conclusions:
In a large population-based stroke study, the proportion of AIS with an unknown mechanism has decreased over time in all demographic groups, while trends in those categorized as cardioembolic or small vessel disease varied by sex and/or race. As changes in imaging utilization may be a contributor to our findings, future work investigating possible sex and race differences in diagnostic evaluations of AIS is warranted.
Abstract WP193: Clinical Profile Of Patients With Non-cardioembolic Ischemic Stroke Or Transient Ischemic Attack Benefiting Most From Dual Antiplatelet Therapy
Authors: Qian Shuo , Trifan Gabriela , Testai Fernando
Published: February 2022

Introduction:
The clinical profile of patients with non-cardioembolic ischemic stroke (IS) or transient ischemic attack (TIA) who benefit from dual antiplatelet therapy (DAPT) is not well established. The aim of this study is to identify those characteristics in this population.

Methods:
We performed a study-level random effects meta-analysis of major randomized controlled clinical trials comparing DAPT to monotherapy antiplatelet treatment (MAPT). Efficacy and safety outcomes were rates of recurrent stroke and major hemorrhage. Baseline demographic and clinical characteristics were recorded. Pooled statistics were calculated as odds ratios (ORs) with 95% confidence intervals (CIs). Heterogeneity was assessed by I
2
. The effects of baseline variables on the log odds ratio of efficacy and safety outcomes for MAPT and DAPT were determined by meta-regression analyses.

Results:
The analysis included 19 studies (N=76407; 50% on DAPT). There were no differences in baseline characteristics between the groups, except for a higher prevalence of previous antiplatelet use in the MAPT arm (OR=1.07; p=0.04). DAPT decreased the odds of recurrent stroke (OR, 0.74, 95% CI, 0.65-0.85, I
2
=66%) and increased odds of major hemorrhage (OR, 1.51, 95% CI, 1.11-2.07, I
2
=76%). In meta-regression analysis, both DAPT and MAPT benefitted patients irrespective of their baseline characteristics, except for patients with increased stroke severity (as measured by NIHSS at presentation) which reduced the risk of recurrent stroke in the DAPT group (r
2
=16%, p<0.05), but not in the MAPT group (p>0.05). Risk of major hemorrhage was increased in patients with history of congestive heart failure (DAPT: OR= -0.001, p=0.02; MAPT: OR= -0.001, p=0.02) and in those with prior antiplatelet use (DAPT: OR= -0.001, p=0.02; MAPT: OR= -0.001, p=0.02).

Conclusions:
MAPT and DAPT reduce the risk of recurrent stroke irrespective of baseline characteristics. However, DAPT, but not MAPT, benefits patients with increased stroke severity. History of congestive heart failure and prior use of antiplatelet have a modest incremental effect in the risk of major hemorrhage.
Abstract WP194: Ldlc Levels, Lipid Lowering Treatment And Recurrent Stroke In Minor Ischemic Stroke Or Tia
Authors: Wangqin Runqi , Pan Yuesong , Xian Ying , Laskowitz Daniel T , Wang Yongjun , Meng Xia , Jiejie Li , Jinxi Lin , Aoming Jin , Hao Li
Published: February 2022

Objective:
To investigate the association between baseline low-density lipoprotein cholesterol (LDL-C) level, lipid lowering treatment and short-term risk of new stroke in patients with a minor ischemic stroke or transient ischemic attack (TIA).

Methods:
We derived data from the Clopidogrel in High-risk patients with Acute Non-disabling Cerebrovascular Events (CHANCE) trial. Patients with a minor stroke or TIA were categorized by LDL-C level at baseline (<100 or ≥100 mg/dL [2.6 mmol/L]) and with or without lipid lowering treatment after symptom onset. The primary outcome was a new ischemic stroke at 3 months. The association of baseline LDL-C level and effect of lowering treatment were assessed.

Results:
Among 3,027 patients, 2,154(71.2%) patients had an initial LDL-C ≥100 mg/dL, of which 1,267(41.9%) received lipid lowering treatment. Elevated LDL-C level was associated with a higher risk of new ischemic stroke at 3 months in patients without lipid lowering treatment (adj.HR=1.35, 95%CI: 1.19-1.53), but not in those with lipid lowering treatment (adj.HR=0.99, 95%CI: 0.82-1.19) (p for interaction=0.007). Patients with LDL-C ≥100 mg/dL had a trend towards higher risk of ischemic stroke (11.8% vs. 8.0%, adj.HR=1.37, 95%CI: 0.96-1.96) in those without lipid lowering treatment. For patients with LDL-C ≥100 mg/dL, lipid lowering treatment was associated with reduced risk of ischemic stroke at 3 months (7.9% vs. 11.8%; adj.HR=0.54, 95%CI: 0.39-0.75).

Conclusions:
Elevated untreated baseline LDL-C level was associated with an increased short-term risk of ischemic stroke among patients presenting with minor ischemic stroke or TIA. There was potential benefit of lipid lowering treatment in stroke patients.
Abstract WP199: Disparities In Post-stroke Evaluation And Treatment According To Pre-stroke Functional Status
Authors: Mistry Eva , Sucharew Heidi , Alwell Kathleen , Mackey Jason , De Los Rios La Rosa Felipe , Demel Stacie L , Ferioli Simona , Jasne Adam , Coleman Elisheva R , SLAVIN Sabreena J , Star Michael , Walsh Kyle B , Haverbusch Mary , Kissela Brett , Kleindorfer Dawn O
Published: February 2022

Introduction:
Stroke patients with a pre-existing disability are less likely to receive acute stroke treatments compared to those without a pre-existing disability. Using the Greater Cincinnati Northern Kentucky (GCNK) Stroke Study, we aimed to understand the disparities in inpatient and outpatient continuum of stroke care according to the patients’ pre-stroke functional status.

Methods:
We ascertained all hospitalized stroke patients ≥18 years old in year 2015 using ICD-9 430-436; ICD-10 I60-I67, G45-G46 within GCNK population; all cases were physician-reviewed. Per-stroke functional status was ascertained by trained research nurses during medical record review. We compared rates of in-hospital rehabilitative therapies, initiation of stroke prevention treatments, inpatient stroke workup (cardiac/vessel imaging), in-hospital and post-discharge rehabilitative therapies between ischemic stroke patients with pre-stroke modified Rankin score (mRS) 0-1 vs ≥2. Logistic regression was used to evaluate the association between pre-stroke mRS and these outcomes adjusting for age, presenting NIHSS, and insurance status.

Results:
Of 2476 patients with ischemic stroke in the GCNK population during 2015, 1326 (53%) had a pre-stroke mRS ≥2. Compared to those with pre-stroke mRS 0-1, these patients were less likely to receive complete stroke workup (aOR 0.86 [0.71-1.04]) and certain stroke prevention treatments (aOR 0.46[0.26-0.81], p<0.01), but more likely to require in-hospital and post-discharge rehabilitative therapies (aOR 2.6[2.11-3.21] and 2.27[1.86-2.77], p<0.01, respectively).

Conclusions:
Ischemic stroke patients with pre-stroke disability were less likely to receive complete in-hospital stroke workup and initiation of certain stroke preventive treatments. Further research into factors driving medical decision-making for stroke patients with a pre-stroke disability is urgently needed to ensure optimal continuum of stroke care.
Abstract WP210: Eicosapentaenoic Acid (EPA) Decreases Cytokine Release And Inflammatory Proteins In Brain Vascular Endothelium During Inflammation
Authors: Sherratt Samuel , Libby Peter , Bhatt Deepak L , Dawoud Hazem , Malinski Tadeusz , Mason Preston
Published: February 2022

Background:
Brain vascular endothelial cell (EC) dysfunction is characterized by release of pro-inflammatory mediators that contribute to atherosclerosis and ischemic stroke. Treatment with icosapent ethyl (IPE), the ethyl ester of the omega-3 fatty acid, eicosapentaenoic acid (EPA), reduced first and total ischemic strokes each by 36%, without increasing hemorrhagic stroke, in statin-treated patients with elevated cardiovascular risk (REDUCE-IT). We tested the effects of EPA on cytokine release and expression of inflammatory proteins from brain microvascular ECs during inflammation.

Methods:
Human brain microvascular endothelial cells (HBECs) were pretreated with the cytokine IL-6 at 12 ng/ml for 2 h before treatment with EPA (40 μM) for 24 h. Proteomic analysis was performed using LC/MS to capture relative expression levels. Only significant changes in protein expression between treatment groups >1-fold were analyzed. Gene set enrichment analysis was also performed on all significantly regulated proteins to identify groups of proteins (pathways) that were affected. Levels of soluble intercellular adhesion molecule-1 (sICAM-1) and tumor necrosis factor-α (TNF-α) were measured by immunochemistry (ELISA).

Results:
IL-6 exposure produced increased levels of sICAM-1 and TNF-α by 102% and 147% (p<0.001), respectively, in brain ECs compared with vehicle. EPA treatment reduced release of sICAM-1 by 43% (p<0.001) and TNF-α by 52% (p<0.001) compared to IL-6 alone. EPA also downregulated 43 proteins involved in the “neutrophil degranulation” pathway in brain ECs (p-adjusted = 2.63 х 10
-12
), including heat shock protein 90-alpha and beta by 1.1-fold each relative to IL-6 alone.

Conclusions:
In brain vascular ECs, EPA significantly reduced expression of pro-inflammatory mediators and proteins associated with neutrophil degranulation under inflammatory conditions. The ability of EPA to reverse brain EC dysfunction during inflammatory may contribute to reductions in stroke risk.
Abstract WP211: Dietary Patterns And Blood Pressure Profiles Among Stroke-free Africans: Evidence From The Stroke Investigative Research And Educational Network Study In Sub-Saharan Africa.
Authors: Okekunle Akinkunmi P , Asowata Osahon J , Owolabi Ayomide , Fakunle Adekunle , Akpa Onoja M , SARFO FRED S , Akpalu Albert , Wahab Kolawole , Obiako Reginald , Komolafe Morenikeji , Owolabi Lukman , Osaigbovo Godwin , Akinyemi Rufus O , Ovbiagele Bruce , Owolabi Mayowa ,   SIREN/SIBS GENOMICS
Published: February 2022

Introduction:
High blood pressure is a prominent risk factor for stroke in Sub-Saharan Africa (SSA) where dietary factors associated with blood pressure are often under-reported.

Hypothesis:
Dietary patterns (DP) are not associated with systolic blood pressure (SBP) and diastolic blood pressure (DBP) among stroke-free Africans from Ghana and Nigeria.

Methods:
Information on diet history (including servings and frequency of consumption) was collected from 4,413 stroke-free persons (recruited from Nigeria and Ghana) and transformed using principal component analysis to estimate seven distinct factor scores that represented seven DP. SBP and DBP measurements were taken using standard operating procedures and linear regression models (adjusting for age, sex, smoking and alcohol use) were applied to estimate beta (β) coefficients and 95% confidence interval (CI) for the association of the DP (using the factor scores) with SBP and DBP at
P
<0.05.

Results:
Mean age was 56.18±14.90years, 48.6% were females, 6.1% reported ever smoked cigarette and 24,8% reported alcohol use. Mean SBP and DBP were 135.53±24.21mmHg and 82.62±14.27mmHg respectively. Seven dietary patterns ('Vegetables', 'Sweetened food&Carbonated drinks', 'Organ & Red meat', 'Processed foods', 'Dairy, Legumes&Whole grains', 'Potatoes, Refined grains&Fish' and 'Fried&Salty foods') were identified in this sample. Overall, factors scores of DP were not significantly associated with SBP, but DBP was significantly reduced by factors of 'Vegetables' patterns (β = -0.60; 95% CI: -1.02, -0.18,
P
=0.005), 'Dairy, Legume&Whole grain' patterns (β = -0.50; 95% CI: -0.92, -0.06,
P
=0.019) and Potatoes, Refined grains & Fish patterns (β = -0.54 (-0.99, 95% CI: -0.10,
P
=0.016).

Conclusion(s):
Adherence to plant-based diets was associated with reduced blood pressure particularly diastolic blood pressure. The association between DP and blood pressure may be complex but dietary advisory encouraging the consumption of plant-based diets may be helpful in the primary prevention of high blood pressure in this population.
Abstract WP219: Lifetime Stress, Acute Stress, And Outcomes After Stroke -- A Longitudinal Study Of Stroke Survivors
Authors: Holman Alison , Teixeira Katie , McGee Breann , Cao Madelyn , Jubb Ashley , Cramer Steve ,   STRONG Study
Published: February 2022

Background:
Stroke is a sudden-onset, unexpected life event over which individuals have little control. These features can make the experience of having a stroke extremely stressful, which may potentiate its debilitating effects. Yet the role of lifetime stress/trauma exposure (LSE) and post-stroke acute stress (AS) have received limited attention in research seeking to identify factors influencing stroke-related disability.

Hypothesis:
Higher lifetime trauma and AS symptoms are associated with poorer post-stroke modified Rankin (mRS) and Fugl-Meyer scores.

Method:
Multi-site national study of patients admitted for a new stroke. Interviews were conducted at 2-10 days (N=763) & 3 months (N=513) post-stroke. Assessments included admission Acute Stress Disorder Interview, day-90 mRS, day-90 upper extremity motor Fugl-Meyer scale (affected side), and LSE. Structural Equation Modeling examined relationships among LSE, AS, and outcomes, controlling for admission NIHSS score, IV TPA treatment, and demographics.

Results:
After controlling for key covariates, AS immediately post-stroke and LSE were both associated with poorer day-90 mRS scores (
p
<.001;
p
=.02 respectively), and higher AS was associated with poorer day-90 Fugl-Meyer scores (
p
=.001). Higher LSE was indirectly associated with poorer day-90 Fugl-Meyer scores (
p
=.009) through its association with high AS (
p
<.001) upon admission.

Conclusion:
Lifetime stress and stress symptoms in the acute stroke setting are both associated with level of disability 3 months post-stroke; their assessment may be useful to facilitate early identification of high-risk patients and development of interventions that help improve functional outcomes after stroke.
Abstract WP223: Coagulation Testing In Embolic Stroke Of Undetermined Source Suggests A Low Frequency Of Paradoxical Embolism In Patients With A Patent Foramen Ovale
Authors: Alshaer Qasem N , RANGARAJU Srikant , Nahab Fadi B
Published: February 2022

Introduction:
Patent foramen ovale (PFO) is present in a significant number of ESUS patients and paradoxical embolism from venous thromboembolism (VTE) is often assumed to be the primary stroke mechanism. We hypothesized that paradoxical embolism is not the primary cause of stroke among ESUS patients with PFO based on markers of coagulation and hemostatic activation (MOCHA).

Methods:
ESUS patients presenting to the Emory Clinic from January 1, 2017 to December 31, 2020 were followed for a median of 13 months (IQR 8.1 - 21.7). MOCHA testing (d-dimer, prothrombin fragment 1.2, thrombin-antithrombin complex, fibrin monomer) was done ≥14 days after stroke and considered abnormal if ≥2 markers were elevated.

Results:
Among 333 ESUS patients (median age 66 years, IQR 53 - 75), 70 (21%) had a PFO. Compared to PFO-, the PFO+ group was younger, had less comorbidities and higher frequency of migraine (Table). No significant difference in abnormal MOCHA among PFO+ and PFO- patients was found (34% vs 45%, p=0.127), including younger patients (<60 years) and those with MOCHA tested <30 days from stroke onset.

Conclusions:
Only 1/3 of PFO+ ESUS patients had abnormal MOCHA with no difference among those with and without PFO, including patients <60 years where paradoxical emboli is commonly presumed. Given that a normal MOCHA profile effectively rules out active VTE or hypercoagulability, a normal MOCHA profile should guide providers to investigate other potential causes.
Abstract WP226: Secondhand Smoking And Odds Of Stroke Among Non-smoking Indigenous Africans From Ghana And Nigeria: A Matched Case-control Study
Authors: Owolabi Mayowa P , Asowata Osahon J , Fakunle Adekunle , Akpa Onoja M , SARFO FRED S , Akpalu Albert , Wahab Kolawole , Obiako Reginald , Komolafe Morenikeji , Owolabi Lukman , Osaigbovo Godwin , Akinyemi Rufus O , Ovbiagele Bruce , Owolabi Mayowa ,   SIREN/SIBS GENOMICS
Published: February 2022

Introduction:
Second-hand smoking (SHS) is an emerging phenomenon in cardiovascular disease (CVD) epidemiology, but whether SHS is associated with stroke is not clearly understood. We assessed the association between SHS and stroke risk in a cohort of West Africans in the Stroke Investigative Research and Educational Network (SIREN) study.

Hypothesis:
SHS is not associated with stroke among indigenous West Africans from Ghana and Nigeria.

Methods:
3131 stroke cases who had never smoked matched (for age and sex) with 3131 healthy smoke-free controls were identified in the multi-centre SIREN study in Ghana and Nigeria. Information on SHS was obtained through the collection of data on regular exposure to exhaled smoke or burning tobacco in an indoor environment. We assessed the relationship between SHS and stroke by estimating the odds ratio (OR) and 95% confidence interval (CI) using conditional logistic regression, adjusting for relevant covariates at
P
<0.05 in a two-sided test.

Results:
The mean age of the participants was 58.8±14.1years (males, 48.0%). History of exposure to SHS was present in 20.2% of the overall sample. The multivariable-adjusted OR for the association between SHS and all stroke events was 1.12 (0.93, 1.34),
P
= 0.210. When the association was stratified by stroke type, the multivariable-adjusted OR were 1.42 (1.03, 1.98)
P
= 0.033 for haemorrhagic stroke and 1.01 (0.80, 1.26)
P
= 0.935 for ischaemic stroke.

Conclusion(s):
SHS was independently associated with higher odds of haemorrhagic stroke, but not ischaemic stroke in this cohort of indigenous West Africans. Intervention(s) to reduce SHS might help lower the burden of stroke in this population, pending longitudinal studies to evaluate the causal effect of SHS on stroke.
Abstract WP229: Eicosapentaenoic Acid (EPA) Modulates Expression Of Thrombotic And Metabolic Proteins In Brain Endothelium Following Cytokine Challenge
Authors: Sherratt Samuel , Libby Peter , Bhatt Deepak L , Dawoud Hazem , Malinski Tadeusz , Mason Preston
Published: February 2022

Background:
During inflammation, vascular endothelial cells (ECs) release vasoconstrictive and thrombotic factors that promote abnormal blood flow and atherothrombosis. The omega-3 fatty acid (n3FA) eicosapentaenoic acid (EPA) reduced first and total ischemic strokes each by 36% in patients with elevated cardiovascular risk (REDUCE-IT) when administered as icosapent ethyl. We measured the effects of EPA on expression of proteins involved in cytoprotection, thrombosis, and fatty acid metabolism in human brain ECs subjected to inflammation.

Methods:
Human brain microvascular ECs (HBECs) were first challenged with IL-6 at 12 ng/ml for 2 hr and then treated with EPA (40 μM) for 24 hr. Global proteomic analysis was performed using LC/MS to measure relative expression levels of >1,000 proteins simultaneously. Only significant (p<0.05) changes in expression between treatment groups >1-fold were analyzed.

Results:
EPA treatment significantly modulated the expression of 504 proteins (212 increased expression, 292 decreased expression) in HBECs compared with IL-6 alone. EPA treatment increased expression of the cytoprotective enzyme heme oxygenase-1 by 1.5-fold (p = 4.7 х 10
-16
) relative to IL-6 alone. Additionally, IL-6 increased expression of prothrombin (clotting factor II) 1.3-fold relative to control (p = 1.41 х 10
-20
), and EPA decreased expression of prothrombin by 1.3-fold relative to IL-6 (p = 2.10 х 10
-24
). EPA also reduced expression of fatty acid desaturase 1 & 2 by 1.4-fold and 2.6-fold, respectively, which may lead to changes in intracellular fatty acid levels.

Conclusions:
EPA significantly modulated expression of cytoprotective, thrombotic, and metabolic proteins in brain ECs under conditions of inflammation with IL-6. These effects of EPA on inflammation have implications for ischemic disease, including stoke, as demonstrated in large outcome trials.
Abstract WP237: Uric Acid Expressed Within Carotid Atherosclerotic Plaque And Serum Uric Acid Are Associated With Cerebrovascular Events
Authors: Nardi Valentina , Franchi Federico , Prasad Megha , Fatica Erica , Alexander Mariam , Bois Melanie C. , Lam Josephine , Meyer Fredric B , Giuseppe Lanzino , Singh Ravinder J. , Lerman Lilach O. , Lerman Amir
Published: February 2022

Introduction:
Uric acid (UA) level within carotid plaque specimens and its association with cerebrovascular events has not been detected or quantified. Systemically, serum uric acid (SUA) is a marker of inflammation and risk factor for atherosclerosis. However, its association with carotid plaque instability and subsequent cerebrovascular events remains unclear.

Hypothesis:
We hypothesized that UA may play a role in carotid artery atherosclerosis and stroke pathogenesis. In patients undergoing carotid endarterectomy (CEA), we aimed to determine whether UA is present differentially in carotid plaques of symptomatic versus asymptomatic patients and whether SUA is associated with cerebrovascular symptoms before surgery and major adverse cardiovascular events (MACE) in the follow-up to CEA.

Methods:
We prospectively collected 32 carotid plaques during CEA. We qualitatively assessed the presence of UA by using Gomori methenamine silver (GMS) staining and immunohistochemistry with anti-UA antibodies. We extracted and measured the quantity of UA in carotid plaques by using an enzymatic colorimetric assay. A retrospective analysis of a clinical database of 534 consecutive patients who underwent CEA was performed. We defined as symptomatic those patients with history of stroke, TIA and amaurosis fugax.

Results:
UA positive staining was detected in higher number of carotid plaques from symptomatic compared to asymptomatic patients on both staining, GMS [20 (86.9%) vs 2 (22.2%); p=0.001] and immunohistochemistry anti-UA [16 (69.5%) vs 1 (11.1%); p=0.004]. Moreover, we found a significantly higher concentration of UA in carotid plaque from symptomatic compared to asymptomatic patients [25.1 (9.5) μg/g vs 17.9 (3.8) μg/g; p=0.021]. SUA level in patients prior to CEA was significantly higher in the symptomatic compared to the asymptomatic group [6.0 (4.8-7.1) mg/dL vs 5.2 (4.4-6.3) mg/dL; p<0.001] and it was significantly higher in patients who developed MACE after CEA versus those that did not [6.0 (4.8-7.1) mg/dL vs 5.4 (4.5-6.6) mg/dL; p=0.021].

Conclusions:
UA may provide a mechanistic explanation as systemic biomarker and potential tissue contributor for carotid plaque instability and subsequent cerebrovascular and cardiovascular symptoms.
Abstract WP240: Beneficial Gut Microbiome-Derived Ligands Can Outcompete Detrimental Brain-Derived Ligands Of Aryl Hydrocarbon Receptor After Stroke
Authors: Honarpisheh Pedram , Lee Juneyoung , Banerjee Anik , Korf Janelle , Ko Kyung Ae , Blasco-Conesa Maria P , Honarpisheh Parisa , Bryan Robert , McCullough Louise , Ganesh Bhanu P
Published: February 2022

Microbiome-derived ligands of the aryl hydrocarbon receptor (AHR) including tryptophan-derived indole acetic acid (IAA) have anti-inflammatory effects in some tissues. However, their effect on neuroinflammation after stroke is unknown. Brain-derived ligands of AHR (e.g. kynurenine) increase post-ischemia and are detrimental. Consistently, pharmacological inhibition of AHR after stroke reduces deleterious effects of kynurenine-mediated activation of AHR and improves outcome. However, whether IAA-mediated activation of AHR is detrimental or beneficial after stroke is unknown. We hypothesized that post-stroke treatment with IAA will reduce neuroinflammation and improve outcomes via beneficial activation of microglial (MG) AHR. We used a reversible middle cerebral artery occlusion (MCAO) model in aged (18mo) WT male mice to investigate temporal changes in biome-derived (IAA) versus host-derived (kynurenine) AHR ligands. Using metabolomics analysis, we determined that plasma levels of IAA can be restored in naïve aged mice by oral probiotics administration of AHR ligand producers. We found that brain kynurenine increases but plasma IAA decreases as early as 3 hours after MCAO in aged mice (n=4/gp,
p=0.0029
) while brain IAA levels remain unchanged. Our 16S rRNA-sequencing shows that aging leads to reduction in AHR ligand-producers (e.g.
Bifidobacterium
[B]
and
Lactobacillus
[L]
). Oral gavage with AHR ligand-producing BBL-probiotic cocktail restored the age-related decline in plasma IAA both acutely (24 hours post-treatment) and chronically (weekly for 6 weeks, n=8/gp,
p=0.0086
and
p=0.0073
, respectively). Further, the increase in plasma levels of IAA after probiotic bacteriotherapy with AHR ligand producers was associated with modulation of AHR activity in the brain (decreased AHR expression in MG, n=8/gp,
p=0.0119
) and reduced MG activation (
p=0.0069
). Our results show that IAA modulates MG-mediated neuroinflammation after stroke. We plan to utilize post-stroke treatment with IAA in aged WT mice and in inducible knock-out mice with microglial
Ahr
deletion to further validate our hypothesis. Future studies are needed to focus on the regulatory function of other biome-derived AHR ligands in post-stroke neuroinflammation.
Abstract WP244: Increased Cardiac Fibrosis In Aged Female Mice May Increase The Risk Of Atrial Arrhythmogenesis And Stroke
Authors: Manwani Bharti , Finger Carson
Published: February 2022

Introduction:
Atrial fibrillation (AF) is an arrhythmia that leads to intracardiac clot formation and cardioembolic strokes. Female sex is an independent risk factor for AF related stroke. This is reflected in the CHA
2
DS
2
-VASc score which is used to stratify AF patients with high, intermediate and low risk of embolism; female sex is an automatic point. The underlying etiology for this sexual dichotomy is unclear. Our laboratory has demonstrated sex differences in atrial tachycardia in aged wild type mice. It is now increasingly recognized that atrial substrate remodeling may lead to increased arrhythmogenesis. We hypothesized that aged females have increased atrial fibrosis leading to enhanced conduction abnormalities and atrial arrhythmias.

Methods:
C57BL6/J wild type aged 20-24 months old male and female mice underwent Echocardiogram (using vevo 3100 imaging system) to measure cardiac output, ejection fraction, stroke volume and left atrial diameter. All mice were sacrificed and cardiac tissue was used for immunohistochemistry. Cardiac sections were stained with masson trichrome stain and Image J was used for quantification of fibrosis. Data was analyzed using two sample t-test on GraphPad PRISM.

Results:
On Echocardiogram, we found no significant difference in cardiac output, ejection fraction and stroke volume in aged male and female mice, p>0.5. We also measured the left atrial diameter in aged male (4.5 ± 0.2mm, n=4) and female mice (3.9± 0.2mm, n=6) and found no significant differences, p>0.05. This demonstrates no baseline cardiac function abnormalities in aged males and females. On masson trichrome staining of the cardiac tissue, there was increased cardiac fibrosis in aged females, fibrotic area 2.3±0.19, n=3, as compared to males, 0.74±0.03, n=8/gp, p=0.02.

Conclusion:
Our results indicate that aged females have increased cardiac fibrosis as compared to aged males, despite having similar and normal cardiac function on echocardiogram. This fibrosis/ atrial substrate remodeling may lead to conduction abnormalities and arrhythmias in aged females. Ongoing studies in our laboratory are evaluating the role of aging and loss of estradiol (at menopause) in atrial substrate remodeling, atrial arrhythmogenesis and stroke risk in aged females.
Abstract WP245: Sex-dependent Regulation Of Mitochondrial Respiratory Function In Mouse Brain Microvessels By Peroxynitrite Decomposition Catalyst
Authors: Sakamuri Siva S , Kolli Lahari , Wisen William P , Sure Venkata N , Evans Wesley R , Lindsey Sarah H , Mostany Ricardo , Katakam Prasad V
Published: February 2022

Background:
Peroxynitrite (PN) is a strong oxidizing and nitrating molecule. PN is a potent inhibitor of mitochondrial respiration and mediates the ischemia-reperfusion injury following stroke. In isolated mouse brain mitochondria, we observed that PN donors inhibit mitochondrial respiratiory function whereas PN decomposition catalyst, Fe (III) tetrakis (1-methyl-4-pyridyl) porphyrin pentachlorideporphyrin pentachloride (FeTMPyP), enhanced mitochondrial state III and state IVo mitochondrial respiration. In addition, we demonstrated that mitochondrial respiration is the primary contributor of cellular energy in brain microvessels (BMVs). The present study tested the hypothesis that FeTMPyP negatively regulates the mitochondrial respiration in the mouse BMVs.

Methods:
BMVs were isolated from male and female mice (C57Bl/6, 2-4 months) using a combination of filters with pore sizes of 300μm and 40μm followed by gradient centrifugation. BMVs were treated with FeTMPyP at 37
o
C for 60 minutes. Oxygen consumption rates (OCR) were measured using the Agilent Seahorse XFe24 analyzer and various respiratory parameters were determined following Mitostress test.

Results:
In the male BMVs, basal respiration, ATP production, and non-mitochondrial respiration were not altered by FeTMPyP treatment. Contrary to our hypothesis, in the male BMVs, PN scavenger decreased the mitochondrial maximal respiration by 24.6% (2.1 ± 0.4 vs 2.8 ± 0.3 picomoles of O
2
/min/μg protein;) whereas the spare respiratory capacity was reduced by 33.3% (1.2 ± 0.3 vs 1.8 ± 0.3 picomoles of O
2
/min/μg protein) (n=17 each, p<0.05). Proton leak was elevated by 70% (0.7 ± 0.1 vs 0.4 ± 0.1 picomoles of O
2
/min/μg protein ) by PN scavenger in male BMVs. In contrast, in the female BMVs, the PN scavenger failed to alter the mitochondrial respiratory parameters (n=15 each, p=NS). Interestingly, FeTMPyP increased non-mitochondrial respiration by 63.8% (0.95 ± 0.2 vs 0.58 ± 0.1 picomoles of O
2
/min/μg protein) in the female BMVs (n=17 each, p<0.05).

Conclusion:
BMVs display sex-dependent respenses to endogenous PN. Notably, in female mouse BMVs, PN appears to act as an antioxidant as PN inhibited the non-mitochondrial respiration which contributes to extramitochondrial superoxide generation.
Abstract WP248: Extended Therapeutic Window Of A Novel Peptide Inhibitor Of Trpm2 Channels On Memory Following Focal Cerebral Ischemia
Authors: Orfila James E , Burch Amelia , Dietz Robert , Schroeder Christian , Mitchell Danae , Minjarez Crystal , Coakley Kelley , Patsos olivia , Herson Paco S
Published: February 2022

Adult stroke is the a leading cause of mortality and morbidity, with significant sequelae including memory deficits. Despite intense research, no pharmacological interventions are currently available to improve cognitive outcome following ischemic stroke (MCAO). Studies suggest that the non-selective transient receptor potential M2 (TRPM2) channels may contribute to brain injury, specifically in males. This study used electrophysiology and neurobehavior to investigate whether TRPM2 could restore cognitive impairments 30 days after MCAO. To assess the functional role of TRPM2 channels, our novel TRPM2 channel antagonist tat-M2NX was administered intravenously 29 days following MCAO, with contextual fear conditioning performed to measure memory function in mice on day 31. Sham operated mice exhibited intact spatial memory, as indicated by high an increase in freezing behavior (65.44% ± 4.167, N=6) whereas) whereas MCAO mice treated with tat-Scr treated reduced freezing behavior (36.7%, ± 24.4 N=7). . Administration of tatM2NX resulted in improved memory function (72.26% ± 10.98 n=9) compared to tatSCR-treated mice. To assess the effect of MCAO on hippocampal long-term potentiation (LTP), a well-accepted model of learning and memory, extracellular field recordings of CA1 neurons were performed in acute hippocampal slices prepared 31 days after MCAO. Under control conditions, a physiological theta burst stimulation (40 pulses, 100Hz) resulted in LTP that increased the slope of fEPSP to 70.8%, n=5 of baseline MCAO injured mice had impaired LTP (121.1%, n=5). However, mice treated with tat-M2NX on day 30 and recorded on day 31 preserved LTP (185.4, n=5), consistent with improved memory function above. This study suggests that TRPM2 channels contribute to the functional memory impairment seen after MAO at delayed timepoints. Therefore, targeting TRPM2 channel activity may be a potential therapeutic approach to improve long-term functional outcome following MCAO.
Abstract WP257: RNS60 Provides Acute And Chronic Protection Of Brain Cells And Function In A Mouse Stroke Model
Authors: Baena-Caldas Gloria P , Li Jie , Pedraza Ortiz Lina Marcela , Ghosh Supurna , Kalmes Andreas , Barone Frank C , Moreno Herman , Hernandez Alejandro
Published: February 2022

Introduction:
RNS60 is an experimental treatment containing oxygen nanobubbles. RNS60 has previously been shown to reduce neuroinflammation and increase neuronal survival in animal models of multiple sclerosis, amyotrophic lateral sclerosis (ALS), Alzheimer's and Parkinson’s diseases, and traumatic brain injury. RNS60 is in phase 2 clinical testing as a treatment for ALS and acute ischemic stroke. Since RNS60 is protective in a variety of pathophysiological conditions that activate neurodegeneration, we evaluated whether RNS60 can reduce brain injury and rescue cognitive functions in a mouse model of ischemic stroke.

Methods:
Male C57BL/6J mice (4 months old) were subjected to transient (60 min) occlusion of the middle cerebral artery (tMCAo) followed by reperfusion, or sham surgery. We investigated the effects of post-stroke RNS60 treatment for 3 or 13 days (beginning 1 hour after reperfusion, 0.2 mL administered i.p., 1/day). Two control treatments (normal saline or oxygenated saline without nanobubbles) were used for comparison. Experimenters were blinded to the treatment groups throughout the study. To assess the post-stroke effects of RNS60 treatments, we performed multiple neurobehavioral tests that included modified neurological severity score (mNSS), novel object recognition (NOR), active place avoidance (APA), and the conflict variant of APA. Brains were collected for assessment of infarct volumes or for immunofluorescence measurements of amyloid, neurons, microglia, and axons.

Results:
Three days of treatment with RNS60 reduced brain infarction, edema, sensory-motor, and cognitive deficits. Thirteen days of treatment reduced brain infarction, amyloid pathology, neuronal cell death, microglial activation, and white matter damage. Noteworthy behavioral effects included recovery of memory during NOR and cognitive flexibility in the APA conflict variant.

Conclusion:
RNS60 treated mice exhibit significant acute and chronic protection of brain cells and neurobehavior after experimental stroke. Our data support the evaluation of RNS60 in clinical stroke trials.
Abstract WP26: Covid Pandemic Versus Pre-pandemic Care Of Stroke Patients Within The Florida Stroke Registry
Authors: Rose David Z ,   Florida Stroke Registry, Wang Kefeng , Gardener Hannah , Gutierrez Carolina M , Koch Sebastian , Dong Chuanhui , Foster Dianne , Jameson Angus , Rundek Tatjana , Romano Jose G , Sacco Ralph L , Asdaghi Negar
Published: February 2022

Background:
The coronavirus 2019 (COVID-19) pandemic has affected all aspects of stroke care delivery and resource allocation. We sought to study this effect utilizing the Florida Stroke Registry (FSR), which collects data from hospitals in large metropolitan cities and small communities, each facing pandemic peaks at different timepoints and within various healthcare system organizations.

Methods:
From March 2019 to March 2021, the FSR identified 82,899 patients with the final diagnosis of ischemic stroke and TIA. Stroke care metrics were compared in patients enrolled during the COVID-19 pandemic (March 2020 to February 2021) to those enrolled in the immediate pre-pandemic year. These metrics included utilization of intravenous thrombolytic (IVT), Endovascular therapy (EVT), Door-To-Needle time (DTN), Door-To-Puncture time (DTP), Door-To-Computed Tomography time (DTCT) and overall Defect-Free Care (DFC).

Results:
Pre-pandemic patients (n= 41,929, 49.0% female, mean age 70.1 ± 14.6 years, 64.3% white, 20.4% black, 15.3% Hispanic) had similar demographics to pandemic patients (48.8% female, mean age 69.9 ± 14.4 years, 65.4% white, 19.9% black, 14.7% Hispanic). Pandemic stroke patients had more severe presentations (median NIHSS 3 [IQR 8] vs 3 [7], p < .0001), longer onset-to-arrival time (242 [677] vs 229 [654] minutes, p = 0.002), and were more likely to arrive via emergency medical services (62.3% vs. 60.8%, p < .0001) than pre-pandemic stroke patients. Although both groups received IVT equally (13.4% vs. 13.5%, p = 0.67), pandemic stroke patients were more likely to receive EVT (7.0% vs. 6.5%, p = 0.005) and had longer DTP (84 [60] vs. 81 [64] minutes, p = 0.01), shorter DTCT (22 [52] vs 23 [56] minutes, p = 0.01) and similar DTN (36 [22] vs. 37 [22] minutes, p = 0.05) times, with an increased DFC rate of 2.2% (86.6% vs. 84.4%, p < .0001).

Conclusions:
In this large registry based study, we found that compared to pre-pandemic care, ischemic stroke patients treated during the COVID19 pandemic presented sicker and later to the hospital and were more likely to receive EVT, but had longer door-to-puncture times. Despite many healthcare delivery challenges imposed by COVID19, Florida hospitals within the FSR maintained high quality of stroke care overall.