Automated scoring of collaterals, blood pressure, and clinical outcome after endovascular treatment in patients with acute ischemic stroke and large-vessel occlusion.

Introduction: We aimed to determine whether the degree of collateral circulation is associated with blood pressure at admission in acute ischemic stroke patients treated with endovascular treatment and to determine its prognostic value. Methods: We evaluated patients with anterior large vessel occlusion treated with endovascular treatment in a single-center prospective registry. We collected clinical and radiological data. Automated and validated software (Brainomix Ltd., Oxford, UK) was used to generate the collateral score (CS) from the baseline single-phase CT angiography: 0, filling of ≤10% of the occluded MCA territory; 1, 11-50%; 2, 51-90%; 3, >90%. When dichotomized, we considered that CS was good (CS = 2-3), or poor (CS = 0-1). We performed bivariate and multivariable ordinal logistic regression analysis to predict CS categories in our population. The secondary outcome was to determine the influence of automated CS on functional outcome at 3 months. We defined favorable functional outcomes as mRS 0-2 at 3 months. Results: We included 101 patients with a mean age of 72.1 ± 13.1 years and 57 (56.4%) of them were women. We classified patients into 4 groups according to the CS: 7 patients (6.9%) as CS = 0, 15 (14.9%) as CS = 1, 43 (42.6%) as CS = 2 and 36 (35.6%) as CS = 3. Admission systolic blood pressure [aOR per 10 mmHg increase 0.79 (95% CI 0.68-0.92)] and higher baseline NIHSS [aOR 0.90 (95% CI, 0.84-0.96)] were associated with a worse CS. The OR of improving 1 point on the 3-month mRS was 1.63 (95% CI, 1.10-2.44) favoring a better CS (p = 0.016). Conclusion: In acute ischemic stroke patients with anterior large vessel occlusion treated with endovascular treatment, admission systolic blood pressure was inversely associated with the automated scoring of CS on baseline CT angiography. Moreover, a good CS was associated with a favorable outcome.

A Polygenic Risk Score Based on a Cardioembolic Stroke Multitrait Analysis Improves a Clinical Prediction Model for This Stroke Subtype.

Background: Occult atrial fibrillation (AF) is one of the major causes of embolic stroke of undetermined source (ESUS). Knowing the underlying etiology of an ESUS will reduce stroke recurrence and/or unnecessary use of anticoagulants. Understanding cardioembolic strokes (CES), whose main cause is AF, will provide tools to select patients who would benefit from anticoagulants among those with ESUS or AF. We aimed to discover novel loci associated with CES and create a polygenetic risk score (PRS) for a more efficient CES risk stratification. Methods: Multitrait analysis of GWAS (MTAG) was performed with MEGASTROKE-CES cohort (n = 362,661) and AF cohort (n = 1,030,836). We considered significant variants and replicated those variants with MTAG p-value < 5 × 10-8 influencing both traits (GWAS-pairwise) with a p-value < 0.05 in the original GWAS and in an independent cohort (n = 9,105). The PRS was created with PRSice-2 and evaluated in the independent cohort. Results: We found and replicated eleven loci associated with CES. Eight were novel loci. Seven of them had been previously associated with AF, namely, CAV1, ESR2, GORAB, IGF1R, NEURL1, WIPF1, and ZEB2. KIAA1755 locus had never been associated with CES/AF, leading its index variant to a missense change (R1045W). The PRS generated has been significantly associated with CES improving discrimination and patient reclassification of a model with age, sex, and hypertension. Conclusion: The loci found significantly associated with CES in the MTAG, together with the creation of a PRS that improves the predictive clinical models of CES, might help guide future clinical trials of anticoagulant therapy in patients with ESUS or AF.

Association of Plaque Inflammation With Stroke Recurrence in Patients With Unproven Benefit From Carotid Revascularization.

BACKGROUND AND OBJECTIVES: In pooled analyses of endarterectomy trials for symptomatic carotid stenosis, several subgroups experienced no net benefit from revascularization. The validated symptomatic carotid atheroma inflammation lumen-stenosis (SCAIL) score includes stenosis severity and inflammation measured by PET and improves the identification of patients with recurrent stroke compared with lumen-stenosis alone. We investigated whether the SCAIL score improves the identification of recurrent stroke in subgroups with uncertain benefit from revascularization in endarterectomy trials. METHODS: We did an individual-participant data pooled analysis of 3 prospective cohort studies (Dublin Carotid Atherosclerosis Study [DUCASS], 2008-2011; Biomarkers and Imaging of Vulnerable Atherosclerosis in Symptomatic Carotid Artery Disease [BIOVASC], 2014-2018; Barcelona Plaque Study, 2015-2018). Eligible patients had a recent nonsevere (modified Rankin Scale score ≤3) anterior circulation ischemic stroke/TIA and ipsilateral mild carotid stenosis (<50%); ipsilateral moderate carotid stenosis (50%-69%) plus at least 1 of female sex, age <65 years, diabetes mellitus, TIA, or delay >14 days to revascularization; or monocular loss of vision. Patients underwent coregistered carotid 18F-fluorodeoxyglucosePET/CT angiography (≤7 days from inclusion). The primary outcome was 90-day ipsilateral ischemic stroke. Multivariable Cox regression modeling was performed. RESULTS: We included 135 patients. All patients started optimal modern-era medical treatment at admission, and 62 (45.9%) underwent carotid revascularization (36 within the first 14 days and 26 beyond). At 90 days, 18 (13.3%) patients had experienced at least 1 stroke recurrence. The risk of recurrence increased progressively according to the SCAIL score (0.0% in patients scoring 0-1, 15.1% scoring 2-3, and 26.7% scoring 4-5; p = 0.04). The adjusted (age, smoking, hypertension, diabetes, carotid revascularization, antiplatelets and statins) hazard ratio for ipsilateral recurrent stroke per 1-point SCAIL increase was 2.16 (95% CI 1.32-3.53; p = 0.002). A score ≥2 had a sensitivity of 100% for recurrence. DISCUSSION: The SCAIL score improved the identification of early recurrent stroke in subgroups who did not experience benefit in endarterectomy trials. Randomized trials are needed to test whether a combined stenosis-inflammation strategy will improve selection for carotid revascularization when benefit is currently uncertain. CLASSIFICATION OF EVIDENCE: This study provides Class II evidence that, in patients with recent anterior circulation ischemic stroke who do not benefit from carotid revascularization, the SCAIL score accurately distinguishes those at risk for recurrent ipsilateral ischemic stroke.

Biological Age Acceleration Is Lower in Women With Ischemic Stroke Compared to Men.

BACKGROUND: Stroke onset in women occurs later in life compared with men. The underlying mechanisms of these differences have not been established. Epigenetic clocks, based on DNA methylation (DNAm) profiles, are the most accurate biological age estimate. Epigenetic age acceleration (EAA) measures indicate whether an individual is biologically younger or older than expected. Our aim was to analyze whether sexual dichotomy at age of stroke onset is conditioned by EAA. METHODS: We used 2 DNAm datasets from whole blood samples of case-control genetic studies of ischemic stroke (IS), a discovery cohort of 374 IS patients (N women=163, N men=211), from GRECOS (Genotyping Recurrence Risk of Stroke) and SEDMAN (Dabigatran Study in the Early Phase of Stroke, New Neuroimaging Markers and Biomarkers) studies and a replication cohort of 981 IS patients (N women=411, N men=570) from BASICMAR register. We compared chronological age, 2 DNAm-based biomarkers of aging and intrinsic and extrinsic epigenetic age acceleration EAA (IEAA and extrinsic EAA, respectively), in IS as well as in individual IS etiologic subtypes. Horvath and Hannum epigenetic clocks were used to assess the aging rate. A proteomic study using the SOMAScan multiplex assay was performed on 26 samples analyzing 1305 proteins. RESULTS: Women present lower Hannum-extrinsic EAA values, whereas men have higher Hannum-extrinsic EAA values (women=-0.64, men=1.24, P=1.34×10-2); the same tendency was observed in the second cohort (women=-0.57, men=0.79, P=0.02). These differences seemed to be specific to cardioembolic and undetermined stroke subtypes. Additionally, 42 blood protein levels were associated with Hannum-extrinsic EAA (P<0.05), belonging to the immune effector process (P=1.54×10-6) and platelet degranulation (P<8.74×10-6) pathways. CONCLUSIONS: This study shows that sex-specific underlying biological mechanisms associated with stroke onset could be due to differences in biological age acceleration between men and women.

Multi-ancestry GWAS reveals excitotoxicity associated with outcome after ischaemic stroke.

During the first hours after stroke onset, neurological deficits can be highly unstable: some patients rapidly improve, while others deteriorate. This early neurological instability has a major impact on long-term outcome. Here, we aimed to determine the genetic architecture of early neurological instability measured by the difference between the National Institutes of Health Stroke Scale (NIHSS) within 6 h of stroke onset and NIHSS at 24 h. A total of 5876 individuals from seven countries (Spain, Finland, Poland, USA, Costa Rica, Mexico and Korea) were studied using a multi-ancestry meta-analyses. We found that 8.7% of NIHSS at 24 h of variance was explained by common genetic variations, and also that early neurological instability has a different genetic architecture from that of stroke risk. Eight loci (1p21.1, 1q42.2, 2p25.1, 2q31.2, 2q33.3, 5q33.2, 7p21.2 and 13q31.1) were genome-wide significant and explained 1.8% of the variability suggesting that additional variants influence early change in neurological deficits. We used functional genomics and bioinformatic annotation to identify the genes driving the association from each locus. Expression quantitative trait loci mapping and summary data-based Mendelian randomization indicate that ADAM23 (log Bayes factor = 5.41) was driving the association for 2q33.3. Gene-based analyses suggested that GRIA1 (log Bayes factor = 5.19), which is predominantly expressed in the brain, is the gene driving the association for the 5q33.2 locus. These analyses also nominated GNPAT (log Bayes factor = 7.64) ABCB5 (log Bayes factor = 5.97) for the 1p21.1 and 7p21.1 loci. Human brain single-nuclei RNA-sequencing indicates that the gene expression of ADAM23 and GRIA1 is enriched in neurons. ADAM23, a presynaptic protein and GRIA1, a protein subunit of the AMPA receptor, are part of a synaptic protein complex that modulates neuronal excitability. These data provide the first genetic evidence in humans that excitotoxicity may contribute to early neurological instability after acute ischaemic stroke.

Frequency, Predictors, Etiology, and Outcomes for Deep Intracerebral Hemorrhage without Hypertension.

OBJECTIVES: Some patients with deep intracerebral hemorrhage (ICH) have a transient hypertensive response and they may be erroneously classified as secondary to hypertension. We investigated frequency, risk factors, and outcomes for patients with deep ICH without hypertension. MATERIALS AND METHODS: We consecutively recruited patients with spontaneous ICH attending two Spanish stroke centers (January 2015-June 2019). Excluded were patients with lobar/infratentorial ICH and patients who died during hospitalization. We defined deep ICH without hypertension when the bleeding was in a deep structure, no requirement for antihypertensive agents during follow-up and no evident chronic hypertension markers evaluated by transthoracic echocardiography, 24 h ambulatory blood pressure monitoring and/or electrocardiography. We compared clinical, radiological, and 3-month functional outcome data for deep-ICH patients with hypertension versus those without hypertension. RESULTS: Of 759 patients with ICH, 219 (mean age 69.6 ± 15.4 years, 54.8% men) met the inclusion criteria and 36 (16.4%) did not have hypertension. Of these 36 patients, 19 (52.7%) had a transient hypertensive response. Independent predictors of deep ICH without hypertension were age (adjusted OR:0.94;95%CI:0.91-0.96) and dyslipidemia (adjusted OR:0.27;95% CI:0.08-0.85). One third of deep ICH without hypertension were secondary to vascular malformations. Favorable outcomes (modified Rankin Scale 0-2) were more frequent in patients with deep ICH without hypertension compared to those with hypertension (70.9% vs 33.8%; p < 0.001). CONCLUSION: Of patients with deep ICH, 16.4% were unrelated with hypertension, around half showed hypertensive response, and around a third had vascular malformations. We suggest studying hypertension markers and performing a follow-up brain MRI in those patients with deep ICH without prior hypertension.

Endothelial Progenitor Cells Count after Acute Ischemic Stroke Predicts Functional Outcome in Patients with Carotid Atherosclerosis.

OBJECTIVES: Circulating Endothelial Progenitor Cells (EPCs) predict cardiovascular outcomes in patients with coronary disease. However, the predictive value of EPCs after ischemic stroke is not well established. We aimed to study the prognostic role of EPCs in patients with acute ischemic stroke and carotid atherosclerosis, focusing on post-stroke functional outcome and stroke recurrences. MATERIALS AND METHODS: We studied consecutive adult patients with an acute (<7 days) anterior circulation ischemic stroke and carotid atherosclerosis. Cardioembolic strokes were excluded. We measured circulating EPCs by flow cytometry (CD34+/CD133+/KDR+) at inclusion (7±1 days after stroke) and at one year of follow-up. At three months and at one year we registered the modified Rankin Scale score, stroke recurrences and coronary syndromes during the follow-up. RESULTS: We studied 80 patients with a mean age of 74.3±10.4 years. We divided the population in tertiles according to the EPCs count. At three months we observed a favorable outcome in 25/36 (69.4%) patients in the lowest, 19/22 (86.4%) in the medium and 21/22 (95.5%) in the highest tercile (p=0.037). In the multivariable analysis a higher EPCs count was associated with favorable functional outcome after adjusting for age and baseline NIHSS score (OR=3.61, 95%CI 1.34-9.76; p=0.011). This association persisted at one year of follow-up. We did not find association between counts of EPCs and stroke recurrence. CONCLUSIONS: In patients with acute ischemic stroke and carotid atherosclerosis, a higher count of EPCs was associated with favorable functional outcome in the mid and long-term follow-up. Counts of EPCs did not predict stroke recurrences.

Cerebral and systemic physiological effects of wearing face masks in young adults.

The COVID-19 pandemic led to widespread mandates requiring the wearing of face masks, which led to debates on their benefits and possible adverse effects. To that end, the physiological effects at the systemic and at the brain level are of interest. We have investigated the effect of commonly available face masks (FFP2 and surgical) on cerebral hemodynamics and oxygenation, particularly microvascular cerebral blood flow (CBF) and blood/tissue oxygen saturation (StO2), measured by transcranial hybrid near-infrared spectroscopies and on systemic physiology in 13 healthy adults (ages: 23 to 33 y). The results indicate small but significant changes in cerebral hemodynamics while wearing a mask. However, these changes are comparable to those of daily life activities. This platform and the protocol provides the basis for large or targeted studies of the effects of mask wearing in different populations and while performing critical tasks.

Carotid Plaque Inflammation Imaged by PET and Prediction of Recurrent Stroke at 5 Years.

BACKGROUND AND OBJECTIVES: To determine whether carotid plaque inflammation identified by 18F-fluorodeoxyglucose (18FDG)-PET is associated with late (5-year) recurrent stroke. METHODS: We did an individual-participant data pooled analysis of 3 prospective studies with near-identical study methods. Eligible patients had recent nonsevere (modified Rankin Scale score ≤3) ischemic stroke/TIA and ipsilateral carotid stenosis (50%-99%). Participants underwent carotid 18FDG-PET/CT angiography ≤14 days after recruitment. 18FDG uptake was expressed as maximum standardized uptake value (SUVmax) in the axial single hottest slice of symptomatic plaque. We calculated the previously validated Symptomatic Carotid Atheroma Inflammation Lumen-Stenosis (SCAIL) score, which incorporates a measure of stenosis severity and 18FDG uptake. The primary outcome was 5-year recurrent ipsilateral ischemic stroke after PET imaging. RESULTS: Of 183 eligible patients, 181 patients completed follow-up (98.9%). The median duration of follow-up was 4.9 years (interquartile range 3.3-6.4 years, cumulative follow-up period 901.8 patient-years). After PET imaging, 17 patients had a recurrent ipsilateral ischemic strokes at 5 years (recurrence rate 9.4%, 95% confidence interval [CI] 5.6%-14.6%). Baseline plaque SUVmax independently predicted 5-year ipsilateral recurrent stroke after adjustment for age, sex, carotid revascularization, stenosis severity, NIH Stroke Scale score, and diabetes mellitus (adjusted hazard ratio [HR] 1.98, 95% CI 1.10-3.56, p = 0.02 per 1-g/mL increase in SUVmax). On multivariable Cox regression, SCAIL score predicted 5-year ipsilateral stroke (adjusted HR 2.73 per 1-point increase, 95% CI 1.52-4.90, p = 0.001). DISCUSSION: Plaque inflammation-related 18FDG uptake improved identification of 5-year recurrent ipsilateral ischemic stroke. Addition of plaque inflammation to current selection strategies may target patients most likely to have late and early benefit from carotid revascularization. CLASSIFICATION OF EVIDENCE: This study provides Class I evidence that in individuals with recent ischemic stroke/TIA and ipsilateral carotid stenosis, carotid plaque inflammation-related 18FDG uptake on PET/CT angiography was associated with 5-year recurrent ipsilateral stroke.

Impact of COVID-19 Infection on the Outcome of Patients With Ischemic Stroke.

BACKGROUND AND PURPOSE: We evaluated whether stroke severity, functional outcome, and mortality are different in patients with ischemic stroke with or without coronavirus disease 2019 (COVID-19) infection. METHODS: A prospective, observational, multicentre cohort study in Catalonia, Spain. Recruitment was consecutive from mid-March to mid-May 2020. Patients had an acute ischemic stroke within 48 hours and a previous modified Rankin Scale (mRS) score of 0 to 3. We collected demographic data, vascular risk factors, prior mRS score, National Institutes of Health Stroke Scale score, rate of reperfusion therapies, logistics, and metrics. Primary end point was functional outcome at 3 months. Favourable outcome was defined depending on the previous mRS score. Secondary outcome was mortality at 3 months. We performed mRS shift and multivariable analyses. RESULTS: We evaluated 701 patients (mean age 72.3±13.3 years, 60.5% men) and 91 (13%) had COVID-19 infection. Median baseline National Institutes of Health Stroke Scale score was higher in patients with COVID-19 compared with patients without COVID-19 (8 [3-18] versus 6 [2-14], P=0.049). Proportion of patients with a favourable functional outcome was 33.7% in the COVID-19 and 47% in the non-COVID-19 group. However, after a multivariable logistic regression analysis, COVID-19 infection did not increase the probability of unfavourable functional outcome. Mortality rate was 39.3% among patients with COVID-19 and 16.1% in the non-COVID-19 group. In the multivariable logistic regression analysis, COVID-19 infection was a risk factor for mortality (hazard ratio, 3.14 [95% CI, 2.10-4.71]; P<0.001). CONCLUSIONS: Patients with ischemic stroke and COVID-19 infection have more severe strokes and a higher mortality than patients with stroke without COVID-19 infection. However, functional outcome is comparable in both groups.

RP11-362K2.2:RP11-767I20.1 Genetic Variation Is Associated with Post-Reperfusion Therapy Parenchymal Hematoma. A GWAS Meta-Analysis.

Stroke is one of the most common causes of death and disability. Reperfusion therapies are the only treatment available during the acute phase of stroke. Due to recent clinical trials, these therapies may increase their frequency of use by extending the time-window administration, which may lead to an increase in complications such as hemorrhagic transformation, with parenchymal hematoma (PH) being the more severe subtype, associated with higher mortality and disability rates. Our aim was to find genetic risk factors associated with PH, as that could provide molecular targets/pathways for their prevention/treatment and study its genetic correlations to find traits sharing genetic background. We performed a GWAS and meta-analysis, following standard quality controls and association analysis (fastGWAS), adjusting age, NIHSS, and principal components. FUMA was used to annotate, prioritize, visualize, and interpret the meta-analysis results. The total number of patients in the meta-analysis was 2034 (216 cases and 1818 controls). We found rs79770152 having a genome-wide significant association (beta 0.09, p-value 3.90 × 10-8) located in the RP11-362K2.2:RP11-767I20.1 gene and a suggestive variant (rs13297983: beta 0.07, p-value 6.10 × 10-8) located in PCSK5 associated with PH occurrence. The genetic correlation showed a shared genetic background of PH with Alzheimer's disease and white matter hyperintensities. In addition, genes containing the ten most significant associations have been related to aggregated amyloid-ß, tau protein, white matter microstructure, inflammation, and matrix metalloproteinases.

Reasons for Not Performing Mechanical Thrombectomy: A Population-Based Study of Stroke Codes.

Background and Purpose: Mechanical thrombectomy (MT) is effective for acute ischemic stroke (AIS) in selected patients with large intracranial vessel occlusion. A minority of patients with AIS receive MT. We aimed to describe the reasons for excluding patients with AIS for MT. Methods: We evaluated patients with AIS in a prospective population-based multicenter registry (Codi Ictus Catalunya registry) that includes all stroke code activations from January to June 2018 in Catalonia, Spain. We analyzed the major reasons for not treating with MT. Results: Stroke code was activated in 3060 patients. Excluding 355 intracranial hemorrhages and 502 stroke mimics, resulted in 2203 patients with AIS (mean age 72.8±13.8 years; 44.6% were women). Of the patients with AIS, 405 (18.4%) were treated with MT. We analyzed the reasons for not treating with MT. The following reasons were considered not modifiable: absence of large intracranial vessel occlusion (922, 41.9%), transient ischemic attack (206, 9.4%), and more than one cause (124, 5.6%). The potentially modifiable reasons for not performing MT by changing selection criteria were as follows: an intracranial artery occlusion that was considered inaccessible or not indicated (48, 2.2%); clinical presentation that was considered too mild to be treated (222, 10.1%); neuroimaging criteria (129, 5.9%), age/prior modified Rankin Scale score/medical comorbidities (129, 5.9%), and therapeutic time window >8 hours (16, 0.7%). Conclusions: In our area, considering all potentially modifiable causes for not performing MT, the percentage of patients with AIS eligible for MT could increase from 18.4% to a maximum of 43.1%. The clinical benefit of this increase is still uncertain and should be confirmed in future trials. Criteria for stroke code activation must be considered for the generalizability of these results.

Blood flow response to orthostatic challenge identifies signatures of the failure of static cerebral autoregulation in patients with cerebrovascular disease.

BACKGROUND: The cortical microvascular cerebral blood flow response (CBF) to different changes in head-of-bed (HOB) position has been shown to be altered in acute ischemic stroke (AIS) by diffuse correlation spectroscopy (DCS) technique. However, the relationship between these relative ΔCBF changes and associated systemic blood pressure changes has not been studied, even though blood pressure is a major driver of cerebral blood flow. METHODS: Transcranial DCS data from four studies measuring bilateral frontal microvascular cerebral blood flow in healthy controls (n = 15), patients with asymptomatic severe internal carotid artery stenosis (ICA, n = 27), and patients with acute ischemic stroke (AIS, n = 72) were aggregated. DCS-measured CBF was measured in response to a short head-of-bed (HOB) position manipulation protocol (supine/elevated/supine, 5 min at each position). In a sub-group (AIS, n = 26; ICA, n = 14; control, n = 15), mean arterial pressure (MAP) was measured dynamically during the protocol. RESULTS: After elevated positioning, DCS CBF returned to baseline supine values in controls (p = 0.890) but not in patients with AIS (9.6% [6.0,13.3], mean 95% CI, p < 0.001) or ICA stenosis (8.6% [3.1,14.0], p = 0.003)). MAP in AIS patients did not return to baseline values (2.6 mmHg [0.5, 4.7], p = 0.018), but in ICA stenosis patients and controls did. Instead ipsilesional but not contralesional CBF was correlated with MAP (AIS 6.0%/mmHg [- 2.4,14.3], p = 0.038; ICA stenosis 11.0%/mmHg [2.4,19.5], p < 0.001). CONCLUSIONS: The observed associations between ipsilateral CBF and MAP suggest that short HOB position changes may elicit deficits in cerebral autoregulation in cerebrovascular disorders. Additional research is required to further characterize this phenomenon.

Defining Minor Intracerebral Hemorrhage.

BACKGROUND AND PURPOSE: The minor stroke concept has not been analyzed in intracerebral hemorrhage (ICH) patients. Our purpose was to determine the optimal cut point on the NIH Stroke Scale (NIHSS) for defining a minor ICH (mICH) in patients with primary ICH. METHODS: An ICH was considered minor if associated with a favorable 3-month outcome (modified Rankin Scale score ≤2). For supratentorial ICH, the discovery cohort consisted of 478 patients prospectively admitted at University Hospital del Mar. Association between NIHSS at admission and 3-month outcome was evaluated with area under the curve-receiver operating characteristics (AUC-ROC) and Youden's index to identify the optimal NIHSS cutoff point to define mICH. External validation was performed in a cohort of 242 supratentorial ICH patients from University Hospital Sant Pau. For infratentorial location, patients from both hospitals (n = 85) were analyzed together. RESULTS: The best -NIHSS cutoff point defining supratentorial-mICH was 6 (AUC-ROC = 0.815 [0.774-0.857] in the discovery cohort and AUC-ROC = 0.819 [0.756-0.882] in the external validation cohort). For infratentorial ICH, the best cutoff point was 4 (AUC-ROC = 0.771 [0.664-0.877]). Using these cutoff points, 40.5% of all primary ICH cases were mICH. Of these, 70.2% were living independently at 3-month follow-up (72% for supratentorial ICH and 56.1% for infratentorial ICH) and 6.5% had died (5.3% for supratentorial ICH, and 14.6% for infratentorial ICH). For patients identified as non-mICH, good 3-month outcome was observed in 11.3% of cases; mortality was 51%. CONCLUSIONS: The definition of mICH using the NIHSS cutoff point of 6 for supratentorial ICH and 4 for infratentorial ICH is useful to identify good outcome in ICH patients.

Single nucleotide variations in ZBTB46 are associated with post-thrombolytic parenchymal haematoma.

Haemorrhagic transformation is a complication of recombinant tissue-plasminogen activator treatment. The most severe form, parenchymal haematoma, can result in neurological deterioration, disability, and death. Our objective was to identify single nucleotide variations associated with a risk of parenchymal haematoma following thrombolytic therapy in patients with acute ischaemic stroke. A fixed-effect genome-wide meta-analysis was performed combining two-stage genome-wide association studies (n = 1904). The discovery stage (three cohorts) comprised 1324 ischaemic stroke individuals, 5.4% of whom had a parenchymal haematoma. Genetic variants yielding a P-value < 0.05 1 × 10-5 were analysed in the validation stage (six cohorts), formed by 580 ischaemic stroke patients with 12.1% haemorrhagic events. All participants received recombinant tissue-plasminogen activator; cases were parenchymal haematoma type 1 or 2 as defined by the European Cooperative Acute Stroke Study (ECASS) criteria. Genome-wide significant findings (P < 5 × 10-8) were characterized by in silico functional annotation, gene expression, and DNA regulatory elements. We analysed 7 989 272 single nucleotide polymorphisms and identified a genome-wide association locus on chromosome 20 in the discovery cohort; functional annotation indicated that the ZBTB46 gene was driving the association for chromosome 20. The top single nucleotide polymorphism was rs76484331 in the ZBTB46 gene [P = 2.49 × 10-8; odds ratio (OR): 11.21; 95% confidence interval (CI): 4.82-26.55]. In the replication cohort (n = 580), the rs76484331 polymorphism was associated with parenchymal haematoma (P = 0.01), and the overall association after meta-analysis increased (P = 1.61 × 10-8; OR: 5.84; 95% CI: 3.16-10.76). ZBTB46 codes the zinc finger and BTB domain-containing protein 46 that acts as a transcription factor. In silico studies indicated that ZBTB46 is expressed in brain tissue by neurons and endothelial cells. Moreover, rs76484331 interacts with the promoter sites located at 20q13. In conclusion, we identified single nucleotide variants in the ZBTB46 gene associated with a higher risk of parenchymal haematoma following recombinant tissue-plasminogen activator treatment.

Patterns of Admission and Outcomes for Patients with Intracranial Hemorrhage in Catalonia, Spain.

BACKGROUND: Limited information is available about the hospital types to which patients with intracerebral hemorrhage (ICH) are admitted and treated. This could be important because some effective therapeutic measures can only be administered at comprehensive stroke centers (CSCs). METHODS: Using the Acute Hospitals Discharge database, which provides population-based information, we identified ICH patients admitted to 7 CSCs and 53 non-CSCs (from January 2015 to December 2016) in Catalonia. CSCs were defined as centers with an emergency department ready to assess and treat code stroke patients around the clock, 24-hour availability of neurology, neurosurgery, and neuroradiology services, and admission to the stroke unit and/or intensive care unit. The database provided the demographics, admitting hospital, and interhospital transfers. Vital status was retrieved from the Central Registry of the Catalan Public Health Insurance. RESULTS: A total of 3339 ICH patients were identified (mean age, 72.2 ± 14.6 years; 56.8% men). Of the 3339 patients, 45.7% were admitted to a CSC and 54.3% to a non-CSC. Transfer from a non-CSC to a CSC occurred for 1.97% of the patients. In-hospital mortality was similar between the CSCs and non-CSCs (30.2% vs. 27.5%; P = 0.09). The long-term mortality was also comparable between the CSC and non-CSC groups (45.4% vs. 47%; P = 0.34). CONCLUSIONS: Despite a considerable proportion of ICH patients remaining at a non-CSC for their entire hospitalization, the short- and long-term mortality were comparable between the 2 hospital types. More studies are required to determine whether outcomes other than mortality might be related to the admitting hospital type and whether the routing protocols for ICH patients should be modified.

Early Neurological Change After Ischemic Stroke Is Associated With 90-Day Outcome.

BACKGROUND AND PURPOSE: Large-scale observational studies of acute ischemic stroke (AIS) promise to reveal mechanisms underlying cerebral ischemia. However, meaningful quantitative phenotypes attainable in large patient populations are needed. We characterize a dynamic metric of AIS instability, defined by change in National Institutes of Health Stroke Scale score (NIHSS) from baseline to 24 hours baseline to 24 hours (NIHSSbaseline - NIHSS24hours = ΔNIHSS6-24h), to examine its relevance to AIS mechanisms and long-term outcomes. METHODS: Patients with NIHSS prospectively recorded within 6 hours after onset and then 24 hours later were enrolled in the GENISIS study (Genetics of Early Neurological Instability After Ischemic Stroke). Stepwise linear regression determined variables that independently influenced ΔNIHSS6-24h. In a subcohort of tPA (alteplase)-treated patients with large vessel occlusion, the influence of early sustained recanalization and hemorrhagic transformation on ΔNIHSS6-24h was examined. Finally, the association of ΔNIHSS6-24h with 90-day favorable outcomes (modified Rankin Scale score 0-2) was assessed. Independent analysis was performed using data from the 2 NINDS-tPA stroke trials (National Institute of Neurological Disorders and Stroke rt-PA). RESULTS: For 2555 patients with AIS, median baseline NIHSS was 9 (interquartile range, 4-16), and median ΔNIHSS6-24h was 2 (interquartile range, 0-5). In a multivariable model, baseline NIHSS, tPA-treatment, age, glucose, site, and systolic blood pressure independently predicted ΔNIHSS6-24h (R2=0.15). In the large vessel occlusion subcohort, early sustained recanalization and hemorrhagic transformation increased the explained variance (R2=0.27), but much of the variance remained unexplained. ΔNIHSS6-24h had a significant and independent association with 90-day favorable outcome. For the subjects in the 2 NINDS-tPA trials, ΔNIHSS3-24h was similarly associated with 90-day outcomes. CONCLUSIONS: The dynamic phenotype, ΔNIHSS6-24h, captures both explained and unexplained mechanisms involved in AIS and is significantly and independently associated with long-term outcomes. Thus, ΔNIHSS6-24h promises to be an easily obtainable and meaningful quantitative phenotype for large-scale genomic studies of AIS.

Multi-ancestry genetic study in 5,876 patients identifies an association between excitotoxic genes and early outcomes after acute ischemic stroke.

During the first hours after stroke onset neurological deficits can be highly unstable: some patients rapidly improve, while others deteriorate. This early neurological instability has a major impact on long-term outcome. Here, we aimed to determine the genetic architecture of early neurological instability measured by the difference between NIH stroke scale (NIHSS) within six hours of stroke onset and NIHSS at 24h (ΔNIHSS). A total of 5,876 individuals from seven countries (Spain, Finland, Poland, United States, Costa Rica, Mexico and Korea) were studied using a multi-ancestry meta-analyses. We found that 8.7% of ΔNIHSS variance was explained by common genetic variations, and also that early neurological instability has a different genetic architecture than that of stroke risk. Seven loci (2p25.1, 2q31.2, 2q33.3, 4q34.3, 5q33.2, 6q26 and 7p21.1) were genome-wide significant and explained 2.1% of the variability suggesting that additional variants influence early change in neurological deficits. We used functional genomics and bioinformatic annotation to identify the genes driving the association from each loci. eQTL mapping and SMR indicate that ADAM23 (log Bayes Factor (LBF)=6.34) was driving the association for 2q33.3. Gene based analyses suggested that GRIA1 (LBF=5.26), which is predominantly expressed in brain, is the gene driving the association for the 5q33.2 locus. These analyses also nominated PARK2 (LBF=5.30) and ABCB5 (LBF=5.70) for the 6q26 and 7p21.1 loci. Human brain single nuclei RNA-seq indicates that the gene expression of ADAM23 and GRIA1 is enriched in neurons. ADAM23 , a pre-synaptic protein, and GRIA1 , a protein subunit of the AMPA receptor, are part of a synaptic protein complex that modulates neuronal excitability. These data provides the first evidence in humans that excitotoxicity may contribute to early neurological instability after acute ischemic stroke. RESEARCH INTO CONTEXT: Evidence before this study: No previous genome-wide association studies have investigated the genetic architecture of early outcomes after ischemic stroke.Added Value of this study: This is the first study that investigated genetic influences on early outcomes after ischemic stroke using a genome-wide approach, revealing seven genome-wide significant loci. A unique aspect of this genetic study is the inclusion of all of the major ethnicities by recruiting from participants throughout the world. Most genetic studies to date have been limited to populations of European ancestry.Implications of all available evidence: The findings provide the first evidence that genes implicating excitotoxicity contribute to human acute ischemic stroke, and demonstrates proof of principle that GWAS of acute ischemic stroke patients can reveal mechanisms involved in ischemic brain injury.

Glycemic variability: prognostic impact on acute ischemic stroke and the impact of corrective treatment for hyperglycemia. The GLIAS-III translational study.

INTRODUCTION: Glycemic variability (GV) represents the amplitude of oscillations in glucose levels over time and is associated with higher mortality in critically ill patients. Our aim is to evaluate the impact of GV on acute ischemic stroke (IS) outcomes in humans and explore the impact of two different insulin administration routes on GV in an animal model. METHODS: This translational study consists of two studies conducted in parallel: The first study is an observational, multicenter, prospective clinical study in which 340 patients with acute IS will be subcutaneously implanted a sensor to continuously monitor blood glucose levels for 96 h. The second study is a basic experimental study using an animal model (rats) with permanent occlusion of the middle cerebral artery and induced hyperglycemia (through an intraperitoneal injection of nicotinamide and streptozotocin). The animal study will include the following 6 groups (10 animals per group): sham; hyperglycemia without IS; IS without hyperglycemia; IS and hyperglycemia without treatment; IS and hyperglycemia and intravenous insulin; and IS and hyperglycemia and subcutaneous insulin. The endpoint for the first study is mortality at 3 months, while the endpoints for the animal model study are GV, functional recovery and biomarkers. DISCUSSION: The GLIAS-III study will be the first translational approach analyzing the prognostic influence of GV, evaluated by the use of subcutaneous glucose monitors, in acute stroke. Trial registration https://www.clinicaltrials.gov (NCT04001049).

Clinical and radiological characteristics and outcome of wake-up intracerebral hemorrhage.

There is little information on the characteristics of patients with wake-up intracerebral hemorrhage (WU-ICH). We aimed to evaluate frequency and relevant differences between WU-ICH and while-awake (WA) ICH patients. This is a retrospective study of a prospective database of consecutive patients with spontaneous ICH, who were classified as WU-ICH, WA-ICH or UO-ICH (unclear onset). We collected demographic, clinical and radiological data, prognostic and therapeutic variables, and outcome [(neurological deterioration, mortality, functional outcome (favorable when modified Rankin scale score 0-2)]. From a total of 466 patients, 98 (25.8%) were classified as UO-ICH according to the type of onset and therefore excluded. We studied 368 patients (mean age 73.9 ± 13.8, 51.4% men), and compared 95 (25.8%) WU-ICH with 273 (74.2%) WA-ICH. Patients from the WU-ICH group were significantly older than WA-ICH (76.9 ± 14.3 vs 72.8 ± 13.6, p = 0.01) but the vascular risk factors were similar. Compared to the WA-ICH group, patients from the WU-ICH group had a lower GCS score or a higher NIHSS score and a higher ICH score, and were less often admitted to a stroke unit or intensive care unit. There were no differences between groups in location, volume, rate of hematoma growth, frequency of intraventricular hemorrhage and outcome. One in five patients with spontaneous ICH are WU-ICH patients. Other than age, there are no relevant differences between WU and WA groups. Although WU-ICH is associated with worse prognostic markers vital and functional outcome is similar to WA-ICH patients.