Acute Intracerebral Hemorrhage Research Articles

Influence of Time to Achieve Target Systolic Blood Pressure on Outcome After Intracerebral Hemorrhage: The Blood Pressure in Acute Stroke Collaboration.

To investigate whether an earlier time to achieving and maintaining systolic blood pressure (SBP) at 120 to 140 mm Hg is associated with favorable outcomes in a cohort of patients with acute intracerebral hemorrhage. We pooled individual patient data from randomized controlled trials registered in the Blood Pressure in Acute Stroke Collaboration. Time was defined as time form symptom onset plus the time (hour) to first achieve and subsequently maintain SBP at 120 to 140 mm Hg over 24 hours. The primary outcome was functional status measured by the modified Rankin Scale at 90 to 180 days. A generalized linear mixed models was used, with adjustment for covariables and trial as a random effect. A total of 5761 patients (mean age, 64.0 [SD, 13.0], 2120 [36.8%] females) were included in analyses. Earlier SBP control was associated with better functional outcomes (modified Rankin Scale score, 3-6; odds ratio, 0.98 [95% CI, 0.97-0.99]) and a significant lower risk of hematoma expansion (0.98, 0.96-1.00). This association was stronger in patients with bigger baseline hematoma volume (>10 mL) compared with those with baseline hematoma volume ≤10 mL (0.006 for interaction). Earlier SBP control was not associated with cardiac or renal adverse events. Our study confirms a clear time relation between early versus later SBP control (120-140 mm Hg) and outcomes in the one-third of patients with intracerebral hemorrhage who attained sustained SBP levels within this range. These data provide further support for the value of early recognition, rapid transport, and prompt initiation of treatment of patients with intracerebral hemorrhage.

Effects of an Early Intensive Blood Pressure-lowering Strategy Using Remifentanil and Dexmedetomidine in Patients with Spontaneous Intracerebral Hemorrhage: A Multicenter, Prospective, Superiority, Randomized Controlled Trial.

Although it has been established that elevated blood pressure and its variability worsen outcomes in spontaneous intracerebral hemorrhage, antihypertensives use during the acute phase still lacks robust evidence. A blood pressure-lowering regimen using remifentanil and dexmedetomidine might be a reasonable therapeutic option given their analgesic and antisympathetic effects. The objective of this superiority trial was to validate the efficacy and safety of this blood pressure-lowering strategy that uses remifentanil and dexmedetomidine in patients with acute intracerebral hemorrhage. In this multicenter, prospective, single-blinded, superiority randomized controlled trial, patients with intracerebral hemorrhage and systolic blood pressure (SBP) 150 mmHg or greater were randomly allocated to the intervention group (a preset protocol with a standard guideline management using remifentanil and dexmedetomidine) or the control group (standard guideline-based management) to receive blood pressure-lowering treatment. The primary outcome was the SBP control rate (less than 140 mmHg) at 1 h posttreatment initiation. Secondary outcomes included blood pressure variability, neurologic function, and clinical outcomes. A total of 338 patients were allocated to the intervention (n = 167) or control group (n = 171). The SBP control rate at 1 h posttreatment initiation in the intervention group was higher than that in controls (101 of 161, 62.7% vs. 66 of 166, 39.8%; difference, 23.2%; 95% CI, 12.4 to 34.1%; P < 0.001). Analysis of secondary outcomes indicated that patients in the intervention group could effectively reduce agitation while achieving lighter sedation, but no improvement in clinical outcomes was observed. Regarding safety, the incidence of bradycardia and respiratory depression was higher in the intervention group. Among intracerebral hemorrhage patients with a SBP 150 mmHg or greater, a preset protocol using a remifentanil and dexmedetomidine-based standard guideline management significantly increased the SBP control rate at 1 h posttreatment compared with the standard guideline-based management.

Age-Specific Association of Co-Morbidity With Home-Time After Acute Stroke.

To examine the association of co-morbidity with home-time after acute stroke and whether the association is influenced by age. We conducted a province-wide study using linked administrative databases to identify all admissions for first acute ischemic stroke or intracerebral hemorrhage between 2007 and 2018 in Alberta, Canada. We used ischemic stroke-weighted Charlson Co-morbidity Index of 3 or more to identify those with severe co-morbidity. We used zero-inflated negative binomial models to determine the association of severe co-morbidity with 90-day and 1-year home-time, and logistic models for achieving ≥ 80 out of 90 days of home-time, assessing for effect modification by age and adjusting for sex, stroke type, comprehensive stroke center care, hypertension, atrial fibrillation, year of study, and separately adjusting for estimated stroke severity. We also evaluated individual co-morbidities. Among 28,672 patients in our final cohort, severe co-morbidity was present in 27.7% and was associated with lower home-time, with a greater number of days lost at younger age (-13 days at age < 60 compared to -7 days at age 80+ years for 90-day home-time; -69 days at age < 60 compared to -51 days at age 80+ years for 1-year home-time). The reduction in probability of achieving ≥ 80 days of home-time was also greater at younger age (-22.7% at age < 60 years compared to -9.0% at age 80+ years). Results were attenuated but remained significant after adjusting for estimated stroke severity and excluding those who died. Myocardial infarction, diabetes, and cancer/metastases had a greater association with lower home-time at younger age, and those with dementia had the greatest reduction in home time. Severe co-morbidity in acute stroke is associated with lower home-time, more strongly at younger age.

Peripheral T cell immune repertoire is associated with the outcomes of acute spontaneous intracerebral hemorrhage.

Systematic immune responses have been identified in patients with acute spontaneous intracerebral hemorrhage (ICH). T cells have been established to participate in central nervous system damage and repair following brain injury. However, their contribution to the prognosis of patients with ICH remains to be elucidated. In this study, peripheral blood mononuclear cells (PBMCs) were collected from 45 patients with acute spontaneous ICH (<24 h from symptom onset). Our results exposed significant negative correlations between hematoma volume/white blood cell (WBC) density and Glasgow Coma Scale (GCS) score. Contrastingly, lymphocyte density was negatively correlated with hematoma volume and positively correlated with GCS score. Moreover, flow cytometry determined that ICH activated T cells despite their proportion being lower in blood. Afterward, immune repertoire sequencing (IR-seq) revealed a significant decrease in VJ, VDJ usage, and TCR clonotypes in ICH patients. Finally, variations in the complementarity-determining region 3 (CDR3) amino acid (aa) were also detected in ICH patients. This study reveals the occurrence of peripheral T-cell diminishment and activation in response to acute hematoma. ICH lesion also alters the T cell receptor (TCR) immune repertoire, which is associated with patient prognosis.

Biological characteristics of Muse cells derived from MenSCs and their application in acute liver injury and intracerebral hemorrhage diseases

The increasing interest in multilineage differentiating stress-enduring (Muse) cells within the field of regenerative medicine is attributed to their exceptional homing capabilities, prolonged viability in adverse conditions, and enhanced three-germ-layer differentiate ability, surpassing their parent mesenchymal stem cells. Given their abundant sources, non-invasive collection procedure, and periodic availability, human menstrual blood-derived endometrium stem cells (MenSCs) have been extensively investigated as a potential resource for stem cell-based therapies. However, there is no established modality to isolate Muse cells from MenSCs and disparity in gene expression profiles between Muse cells and MenSCs remain unknown. In this study, Muse cells were isolated from MenSCs by long-time trypsin incubation method. Muse cells expressed pluripotency markers and could realize multilineage differentiation in vitro. Compared with MenSCs, Muse cells showed enhanced homing ability and superior therapeutic efficacy in animal models of acute liver injury (ALI) and intracerebral hemorrhage (ICH). Furthermore, the RNA-seq analysis offers insights into the mechanism underlying the disparity in trypsin resistance and migration ability between Muse and MenSCs cells. This research offers a significant foundation for further exploration of cell-based therapies using MenSCs-derived Muse cells in the context of various human diseases, highlighting their promising application in the field of regenerative medicine.

A Prospective Cohort Study of Elevated Serum NLRP1 Levels to Prognosticate Neurological Outcome After Acute Intracerebral Hemorrhage at a Single Academic Institution.

Nucleotide-binding oligomerization domain-like receptor family pyrin domain-containing 1 (NLRP1) participates in neuroinflammation. This study aimed to identify serum NLRP as a potential prognostic biomarker of acute intracerebral hemorrhage (ICH). This prospective cohort study enrolled 145 patients with supratentorial ICH and 51 healthy controls. Serum NLRP1 levels were quantified on admission of all 145 patients, on days 1, 3, 5, 7, and 10 after stroke in 51 of 145 patients and at entry into the study of controls. Poststroke 6-month modified Rankin Scale (mRS) scores of 3-6 signified a poor prognosis. Compared to controls, patients had prominently increased serum NLRP1 levels until day 10 after ICH, with the highest levels at days 1 and 3. Serum NLRP1 levels were independently correlated with National Institutes of Health Stroke Scale (NIHSS) scores, hematoma volume and six-month mRS scores, and independently predicted six-month bad prognosis. A linear relationship was observed between serum NLRP1 levels and the risk of poor prognosis in a restricted cubic spline. Under the receiver operating characteristic (ROC) curve, serum NLRP levels efficiently discriminated poor prognosis. Serum NLRP1, NIHSS, and hematoma volume were merged into a prognosis prediction model, which was portrayed using a nomogram. Good performance of the model was verified using calibration curve, decision curve, and ROC curve. Serum NLRP1 levels are elevated during the early period following ICH and are independently related to hemorrhagic severity and poor prognosis, suggesting that serum NLRP1 may represent a promising prognostic biomarker of ICH.

Enhancing blood pressure management protocol implementation in patients with acute intracerebral haemorrhage through a nursing-led approach: A retrospective cohort study.

To evaluate the impact of nurse care changes in implementing a blood pressure management protocol on achieving rapid, intensive and sustained blood pressure reduction in acute intracerebral haemorrhage patients. Retrospective cohort study of prospectively collected data over 6 years. Intracerebral haemorrhage patients within 6 h and systolic blood pressure ≥ 150 mmHg followed a rapid (starting treatment at computed tomography suite with a target achievement goal of ≤60 min), intensive (target systolic blood pressure < 140 mmHg) and sustained (maintaining target stability for 24 h) blood pressure management plan. We differentiated six periods: P1, stroke nurse at computed tomography suite (baseline period); P2, antihypertensive titration by stroke nurse; P3, retraining by neurologists; P4, integration of a stroke advanced practice nurse; P5, after COVID-19 impact; and P6, retraining by stroke advanced practice nurse. Outcomes included first-hour target achievement (primary outcome), tomography-to-treatment and treatment-to-target times, first-hour maximum dose of antihypertensive treatment and 6-h and 24-h systolic blood pressure variability. Compared to P1, antihypertensive titration by stroke nurses (P2) reduced treatment-to-target time and increased the rate of first-hour target achievement, retraining of stroke nurses by neurologists (P3) maintained a higher rate of first-hour target achievement and the integration of a stroke advanced practice nurse (P4) reduced both 6-h and 24-h systolic blood pressure variability. However, 6-h systolic blood pressure variability increased from P4 to P5 following the impact of the COVID-19 pandemic. Finally, compared to P1, retraining of stroke nurses by stroke advanced practice nurse (P6) reduced tomography-to-treatment time and increased the first-hour maximum dose of antihypertensive treatment. Changes in nursing care and continuous education can significantly enhance the time metrics and blood pressure outcomes in acute intracerebral haemorrhage patients. STROBE guidelines. No Patient or Public Contribution.

Accuracy of automated segmentation and volumetry of acute intracerebral hemorrhage following minimally invasive surgery using a patch-based convolutional neural network in a small dataset

PurposeIn cases of acute intracerebral hemorrhage (ICH) volume estimation is of prognostic and therapeutic value following minimally invasive surgery (MIS). The ABC/2 method is widely used, but suffers from inaccuracies and is time consuming. Supervised machine learning using convolutional neural networks (CNN), trained on large datasets, is suitable for segmentation tasks in medical imaging. Our objective was to develop a CNN based machine learning model for the segmentation of ICH and of the drain and volumetry of ICH following MIS of acute supratentorial ICH on a relatively small dataset.MethodsNinety two scans were assigned to training (n = 29 scans), validation (n = 4 scans) and testing (n = 59 scans) datasets. The mean age (SD) was 70 (± 13.56) years. Male patients were 36. A hierarchical, patch-based CNN for segmentation of ICH and drain was trained. Volume of ICH was calculated from the segmentation mask.ResultsThe best performing model achieved a Dice similarity coefficient of 0.86 and 0.91 for the ICH and drain respectively. Automated ICH volumetry yielded high agreement with ground truth (Intraclass correlation coefficient = 0.94 [95% CI: 0.91, 0.97]). Average difference in the ICH volume was 1.33 mL.ConclusionUsing a relatively small dataset, originating from different CT-scanners and with heterogeneous voxel dimensions, we applied a patch-based CNN framework and successfully developed a machine learning model, which accurately segments the intracerebral hemorrhage (ICH) and the drains. This provides automated and accurate volumetry of the bleeding in acute ICH treated with minimally invasive surgery.

Early blood pressure lowering therapy is associated with good functional outcome in patients with intracerebral hemorrhage

BackgroundThe implementation of a care bundle might improve functional outcome for patients with intracerebral hemorrhage (ICH). However, the impact of anti-hypertensive treatment on ICH outcomes remains uncertain. Our objective is to examine whether early blood pressure (BP) lowering therapy within first 12 h is associated with good outcome in ICH patients.MethodsWe included acute ICH patients who had baseline computed tomography (CT) scans within 6 h after onset of symptoms between October 2013 and December 2021. Early BP reduction was defined as use of anti-hypertensive agents within 12 h after onset of symptom. The clinical characteristics were compared between patients who received early BP lowering therapy and those without. The associations between early BP lowering and good outcome and functional independence at 3 months were assessed by using multivariable logistic regression analyses.ResultsA total of 377 patients were finally included in this study for outcome analysis. Of those, 212 patients received early BP reduction within 12 h after ICH. A total of 251 (66.6%) patients had good outcome. After adjustment for age, admission systolic BP, admission GCS score, baseline hematoma volume, hematoma expansion, and presence of intraventricular hemorrhage, early BP lowering therapy was associated with functional independence (adjusted odd ratio:1.72, 95% confidence interval:1.03–2.87; P = 0.039) and good outcome (adjusted odd ratio: 2.02, 95% confidence interval:1.08–3.76; P = 0.027).ConclusionsIn ICH patients presenting within 6 h after symptom onset, early BP reduction within first 12 h is associated with good outcome and functional independence when compared to those who do not undergo such early intervention. Implementation of quality measures to ensure early BP reduction is crucial for management of ICH.

Independent Factors Associated with 30-Day In-Hospital Mortality from Acute Spontaneous Intracerebral Hemorrhage

ObjectiveThis study aims to investigate independent factors associated with 30-day mortality in patients with acute spontaneous intracerebral hemorrhage before treatment. MethodsA retrospective analysis was performed on medical records of patients hospitalized with acute spontaneous intracerebral hemorrhage between 2019 and 2021. Data included personal history, hospital stay duration, symptom onset, chief complaint, underlying diseases, medication, and alcohol/smoking habits. Physical examination records comprised baseline blood pressure, Glasgow Coma Scale assessment, and pupil reaction evaluation. Diagnostic imaging, specifically CT brain scans, was examined for hemorrhage details. Multivariable logistic analysis was utilized for data analysis. ResultsAmong 663 cases, 185 (27.9%) experienced mortality. Risk factors for mortality included chronic kidney disease, ischemic heart disease, loss of follow-up in hypertension clinic, and pontine hemorrhage. Conversely, motor response, reactive pupils, and basal cistern persistence significantly decreased the risk of mortality in multivariable analysis. ROC analysis identified a motor response score of 5 as the cutoff for predicting survival. ConclusionChronic kidney disease, ischemic heart disease, loss of hypertension follow-up, motor response, reactive pupils, pontine hemorrhage, and basal cistern persistence were independent variables associated with the 30-day mortality rate in spontaneous intracerebral hemorrhage patients before treatment initiation. A motor response, pupil reaction, and basal cistern persistence serve as predictive tools for assessing mortality in SICH before treatment.

Predicting hematoma expansion in acute spontaneous intracerebral hemorrhage: integrating clinical factors with a multitask deep learning model for non-contrast head CT

PurposeTo predict hematoma growth in intracerebral hemorrhage patients by combining clinical findings with non-contrast CT imaging features analyzed through deep learning.MethodsThree models were developed to predict hematoma expansion (HE) in 572 patients. We utilized multi-task learning for both hematoma segmentation and prediction of expansion: the Image-to-HE model processed hematoma slices, extracting features and computing a normalized DL score for HE prediction. The Clinical-to-HE model utilized multivariate logistic regression on clinical variables. The Integrated-to-HE model combined image-derived and clinical data. Significant clinical variables were selected using forward selection in logistic regression. The two models incorporating clinical variables were statistically validated.ResultsFor hematoma detection, the diagnostic performance of the developed multi-task model was excellent (AUC, 0.99). For expansion prediction, three models were evaluated for predicting HE. The Image-to-HE model achieved an accuracy of 67.3%, sensitivity of 81.0%, specificity of 64.0%, and an AUC of 0.76. The Clinical-to-HE model registered an accuracy of 74.8%, sensitivity of 81.0%, specificity of 73.3%, and an AUC of 0.81. The Integrated-to-HE model, merging both image and clinical data, excelled with an accuracy of 81.3%, sensitivity of 76.2%, specificity of 82.6%, and an AUC of 0.83. The Integrated-to-HE model, aligning closest to the diagonal line and indicating the highest level of calibration, showcases superior performance in predicting HE outcomes among the three models.ConclusionThe integration of clinical findings with non-contrast CT imaging features analyzed through deep learning showed the potential for improving the prediction of HE in acute spontaneous intracerebral hemorrhage patients.

Abstract WP176: Hemoglobin Decrement is Associated With Ischemic Lesions on Brain MRI of Patients With Acute Intracerebral Hemorrhage

Background: We have previously identified that hemoglobin decrements and new-onset anemia during an intracerebral hemorrhage (ICH) hospitalization is frequent, rapid, and associates with poor outcome. Though this association may be related to impaired cerebral oxygen delivery, it is unclear whether these changes relate to cerebral ischemia. We investigated the relationship of hemoglobin decrements over time and ischemic lesions on brain MRI during an ICH hospitalization. Methods: Consecutive patients with acute spontaneous ICH enrolled into a single-center, prospective cohort study between 2009 and 2019 were assessed. Patients who had a brain MRI and serial hemoglobin measurements were included. Change in hemoglobin from admission to date of brain MRI (delta Hgb) was defined as the exposure. The outcome was the presence of remote ischemic lesions, defined as foci of diffusion restriction &gt;10 mm away from the hematoma on brain MRI. A regression model assessed relationships between delta Hgb and DWI brain lesions, adjusting for baseline demographics, ICH severity, and time to MRI. Separate sensitivity models were adjusted for admission systolic blood pressure and hemoglobin. Results: We identified 189 ICH patients with brain MRI and serial hemoglobin measurements during their hospitalization. The mean age was 66.5 (SD 14.8) and 49.2% were female. Mean admission hemoglobin was 13.5 g/dL (SD 2.0), mean change in hemoglobin from admission to day of MRI was -1.6 (SD 1.6), median time from ICH onset to MRI was 2 (IQR 1-4) days, and 31.7% of patients had ischemic lesions on MRI. We identified an association of greater decrements in hemoglobin with ischemic lesions in our primary model (adjusted OR 0.79, 95%CI 0.64-0.99, p=0.04). Sensitivity analyses adjusting for admission systolic blood pressure and hemoglobin did not change this association. Conclusions: Greater hemoglobin decrements associate with remote ischemic lesions on brain MRI of patients with acute ICH. Further work is needed to assess drivers of anemia after ICH and possible causal mechanisms for ischemic brain injury to assess whether anemia is a modifiable treatment target to improve ICH outcomes.

Abstract TMP84: Multi-Institutional Validation of an Automated Segmentation Tool for Intracerebral Hemorrhage (ICH) and Peri-Hematomal Edema (PHE) on Head CT

Objective: In patients with acute intracerebral hemorrhage (ICH), the volume of hemorrhage, and perihematomal edema (PHE) are representative of primary, and secondary brain injury, respectively. Automated quantification of ICH and PHE volumes from admission non-contrast head CT can facilitate evaluation of large stroke datasets, and expedite treatment triage when volume cutoffs are applied. We aimed to train and externally validate an automated model for segmentation and quantification of ICH and PHE volumes on non-contrast head CT scans. Methods: For training of the model, we used the data from multicentric ATACH-2 clinical trial with head CTs from eleven medical institutes in six countries. The model was then exported and tested on two external datasets from Yale and University of Berlin. We designed an automated pipeline for extracting brain window from 3D non-contrast head CT, skull stripping, resampling to homogenous voxel size, and segmentation. For segmentation we applied a deep learning model based on 3D full resolution nnUNet. We used the Dice Similarity Coefficient (DSC), Hausdorff Distance (HD), and Volume Similarity (VS) between automated segmentation and ground truth manual segmentation volumes to evaluate the models’ performance. Results: A total of 854 patients from the ATACH-2 trial (854 х2, baseline and follow-up CT scans) were used for training of the model in 5-fold cross-validation. In validation folds, the model achieved a mean DSC=0.90±0.10, HD =1.42±16.0mm, and VS=0.95±0.10 for ICH; and DSC=0.74±0.12, HD =3.0±16.5 mm, and VS=0.91±0.12 for PHE. In the externaltesting cohort from Yale (200 patients х2, baseline and follow-up CT scans), the model archieved median DSC=0.93, HD=0.98 mm, and VS=0.97 for ICH; and median DSC=0.69, HD=4.52 mm, and VS=0.84 for PHE. In the externaltesting cohort from Charité Hospital, University of Berlin (915 baseline CT scans), the model archived median DSC=0.87, HD=4 mm, and VS=0.90 for ICH; and median DSC=0.65, HD=5 mm, VS=0.85 for PHE. Conclusion: We trained, validated, and externally tested an end-to-end automated tool for segmentation of both ICH and PHE on non-contrast head CT. Such tool can facilitate treatment triage for trials when volume cutoffs are applied for enrollment.

Abstract WMP78: Mobile Stroke Units Enable Hyperacute Interventions for Intracerebral Hemorrhage

Introduction: Mobile stroke units (MSUs) are an evolving means to expedited acute stroke management. Recent landmark trials BEST-MSU and B_PROUD have proven that MSUs facilitate quicker thrombolysis times and improved functional outcomes at 90 days when compared to conventional emergency medical services (EMS) for acute ischemic stroke patients. Despite the growing body of literature surrounding MSUs and acute ischemic stroke, literature describing the intracerebral hemorrhage experience in MSUs has been lacking. Methods: Retrospective analysis of consecutive patients with acute intracerebral hemorrhage triaged by MSU or EMS from January 2018 to December 2022 was performed at two tertiary institutions. In the EMS cohort, only patients seen between 8 am to 8 pm, corresponding to the operating hours of the MSU, were included. Goal blood pressure was defined as systolic blood pressure &lt;160. Chi-squared test for categorical variables and t-test for continuous variables were used for statistical analysis. Results: A total of 146 MSU patients were compared to 221 EMS patients. Both cohorts had similar baseline demographics. Median initial blood pressure in the MSU was 190/99, which dropped to a median blood pressure of 157/80 upon arrival to the hospital. Initial systolic blood pressure in the hospital was significantly higher for EMS compared to MSU patients (166 vs 157, p=0.011). The majority (77%) of MSU patients received anti-hypertensive medications while in the MSU. Times from door to CT completion (14 vs 33 min, p=0.000), anticoagulation reversal (99 vs 139 min, p=0.013), anti-hypertensive medication administration (21 vs 45 min, p=0.020), and goal blood pressure (35 vs 51 min, p=0.000) were significantly faster in the MSU cohort. Conclusions: MSUs provide faster medical treatment for patients with acute intracerebral hemorrhage. The target blood pressure goal was met much quicker in the MSU. Faster time metrics convey a hypothetical benefit towards improved patient outcomes.

Abstract 57: Rapid Prehospital Diagnosis of Intracerebral Hemorrhage by Measuring GFAP on a Point-of-Care Platform

Background: The rapid differentiation between intracerebral hemorrhage (ICH) and ischemic stroke (IS) in patients with symptoms of acute stroke is decisive for triage and initiation of targeted therapies. Glial fibrillary acidic protein (GFAP) is a highly promising blood biomarker indicating acute ICH. In this study we investigated the potential of a new GFAP plasma test on a point-of-care (POC) platform for rapidly distinguishing ICH from IS in the prehospital phase. Methods: Patients with symptoms of acute stroke admitted within 6 hours of symptom onset were enrolled. Blood samples were collected already in the prehospital phase in most patients. Plasma GFAP measurements were performed on the i-STAT Alinity® (Abbott) device (duration of analysis 15 min). The primary endpoint was the final diagnosis at hospital discharge categorized as ICH, IS or stroke mimics. Results: 155 patients were enrolled (mean age 75±13, 49% females; final diagnosis 33 ICH, 115 IS, 7 stroke mimics). Prehospital GFAP serum concentrations were strongly elevated in ICH patients compared to IS patients (mean 2283±3821 pg/mL, median 144 [IQR 52.5-2562] vs. mean 45±25 pg/mL, median 29 [IQR 29-53]; p&lt;0.001). In patients with a moderate to severe neurological deficit (NIHSS &gt; 7), GFAP values below 30 pg/mL were associated with a negative predictive value of 100% (i.e. ruling out ICH). The probability of ICH increased in parallel with higher GFAP levels. GFAP concentrations above 120 pg/mL indicated ICH with a positive predictive value of 94%. Conclusion: Rapid prehospital GFAP measurements on a point-of-care platform allow a reliable differentiation between patients with IS and ICH. This opens the potential for optimized triage and for the administration of antidots in severely affected patients with suspected anticoagulation-associated ICH.

Abstract WMP82: Peri-Hematomal Edema (PHE) Shape Features as Independent Predictors of the 3-month Outcome in Acute Supratentorial Intracerebral Hemorrhage (ICH)

Background: Perihematomal edema (PHE) is a marker of post-ICH secondary brain injury and a potential treatment target. However, different studies have reported equivocal results regarding the optimal metrics of PHE volume in relation to clinical outcomes - such as absolute, and relative baseline PHE volume, or the rate of PHE volume growth over the first 24- and 72-hours post-ICH. In this study, we examined the association of different PHE shape features at baseline and 24-hour with outcome at 3-month follow-up. Methods: We used the data from ATACH-2 trial. We manually segmented ICH and PHE on baseline and follow-up CTs, and extracted 14 shape features. We explored the association of baseline, follow-up, difference (baseline subtracted from follow-up) and temporal rate (difference divided by time gap) of PHE shape changes with 3-month mRS. We applied Spearman correlation to assess univariate associations, and multivariate stepwise regression to evaluate if PHE shape features independently predict outcome adjusting for age, sex, NIHSS, GCS, baseline ICH volume, and treatment. Results: 796 patients were included. Baseline PHE maximum diameters across various planes, main axes, volume, surface and sphericity correlated with 3-month mRS after adjusting for multiple comparisons. The 24-hour difference and temporal change rates of these features also had significant association with outcome - but not the 24-hour absolute values. In multivariate regression, baseline PHE shape sphericity (p=0.029) and voxel volume (p=0.026), alongside admission NIHSS (p&lt; 0.001), ICH volume (p=0.002), and age (p&lt;0.001) were independent predictors of favorable outcomes. Conclusion: Aside from metrics of volume, PHE sphericity at baseline is an independent prognostic factor, with less spheric (more irregular) shape associated with worse outcome. In addition, baseline PHE shape features - compared to changes over the first 24 hours post-ICH - had stronger prognostic associations.

Abstract 67: Risk and Time-Course of Post-Stroke Dementia: A Population-Wide Cohort Study, 2002-2022

Background: People with acute stroke are at high risk of dementia. Population-wide data on the risk and time-course of dementia after stroke are lacking. Methods: We conducted a population-wide analysis of over 15 million people in Ontario, Canada between 2002-2022. Using linked administrative databases, we compared all 90-day survivors of first acute ischemic stroke or intracerebral hemorrhage (ICH) to controls in the general population and with acute myocardial infarction (AMI) by matching 1:1 on age, sex, rural residence, neighborhood marginalization, and vascular comorbidities, and excluded people with prior dementia. We evaluated the rate of dementia per 100 person-years using a validated definition which included hospitalization, physician claims, and medications, and calculated cause-specific hazard ratios overall and across follow-up time. Results: We identified 180,940 people with acute stroke, of which 33,765 (18.7%) developed dementia over mean follow-up of 5.5 years (max 20y). The rate of dementia per 100 person-years was highest after acute stroke compared to the general population (3.40 vs. 1.88) and compared to AMI (3.23 vs. 1.81). The overall risk of dementia was higher in those with acute stroke compared to the general population (HR 1.79, 95% CI 1.76-1.82; Figure 1A), and particularly after ICH (HR 2.43, 2.31-2.57). The results were similar when compared to AMI (HR 1.77, 1.74-1.80; Figure 1C). There was an almost 3-fold elevation of dementia risk in the first year after stroke, decreasing to 1.5-fold by 5 years and remaining elevated even 20 years after (Figure 1B/1D). Conclusion: In this large, population-wide study almost one fifth of people developed dementia after stroke, with an 80% higher risk of developing dementia compared to matched controls. The risk was highest early after stroke but remained elevated 20 years after, raising the urgency of developing interventions for dementia prevention in acute and chronic survivors of stroke.

Abstract 134: Thrombotic Complications of Ovarian Hyperstimulation Syndrome

Introduction: Ovarian hyperstimulation syndrome (OHSS) is a well-known complication of ovarian stimulation used during assisted reproductive technology cycles. In severe OHSS, increases in capillary permeability can result in hemoconcentration and hypercoagulability leading to thrombotic events, including stroke and cerebral venous thrombosis. Herein we sought to determine the prevalence of hospitalization for thrombotic events shortly after OHSS using population-level data. Methods: We conducted two separate retrospective cohort studies of patients with OHSS using publicly available datasets: (1) administrative claims data from the Healthcare Cost and Utilization Project (HCUP) across 11 states from 2016 to 2020 and (2) National Inpatient Sample (NIS) registry data from the end of 2015 to 2020. HCUP contains both emergency department and inpatient encounters whereas NIS contains a nationally representative sample of inpatient encounters. For our study, all female patients with an encounter for OHSS, defined using International Classification of Diseases, Tenth Revision, Clinical Modification (ICD-10-CM) code N98.1 were included from each dataset. Our primary study outcome was any stroke or major thrombotic event identified within 60 days of OHSS diagnosis in HCUP or during the index admission for OHSS in NIS. We used previously validated ICD-10-CM codes for acute ischemic stroke, intracerebral and subarachnoid hemorrhage, cerebral venous thrombosis, acute myocardial infarction, pulmonary embolism, and acute deep venous thrombosis to define our study outcome. Results: We identified a total of 747 patients with OHSS in HCUP. Within the HCUP cohort, fewer than 10 patients (&lt;1%) were hospitalized with a stroke or thrombotic event within 60 days of OHSS diagnosis. There were 1,955 hospitalizations for OHSS in NIS. There were 20 (1%) pulmonary embolisms and 35 (1.8%) acute deep venous thromboses, but no other stroke/thrombotic complications in NIS. Conclusions: We found very few thrombotic events shortly after OHSS diagnosis using two large datasets. The low rate of outcome events after OHSS seen in each of our population-level analyses increases the reliability of these study results.

Abstract TP258: Social Network Features Involved in Stroke Decision Making During Acute Stroke

Introduction: 80% of strokes occur in the company of others and 70% take place at home. However, research on prehospital delay has overlooked the social nature of stroke detection and triage. In the Time is Brain study, we aim to understand how a patient’s social network affects the decision to seek medical care during stroke symptom onset. Methods: We conducted in-depth interview in 78 patients (ages 30 to 90 years) in the longitudinal, multicenter Time is Brain study. During the interview, we mapped and examined relationships and interactions between patients and individuals involved in the decision-making process during the stroke. We enrolled during their initial stroke hospitalization at Mass General Brigham or Yale New Haven Hospital. Eligibility criteria include having an acute stroke syndrome presentation that may include diagnoses of acute ischemic stroke, intracerebral hemorrhage (ICH), or transient ischemic attack (TIA). Trauma-related syndromes, such as subdural hemorrhage, were excluded. Results: 82.5% (n=66) of patients were accompanied by at least one other person during symptom onset. 60% (n=48) contacted at least one other person. 82.5% (n=66) of strokes occurred in a home-setting and 17.5% (n=14) occurred at work or another public space. 36.25% (n=29) of patients identified their spouse as the first person made aware of symptoms. Men were more likely than women to be accompanied by a spouse (X 2 = 6.8211, p-value = 0.03302). Conclusions: Building on prior studies that have highlighted the important role of the social environment in stroke detection and triage, this is a high-resolution study of the social agents and behaviors driving stroke decision-making. These findings highlight the active and often lengthy communication, and unspoken observations that shape layperson decisions during stroke crises. These data are important to identify mechanisms of prehospital delay and build social network-based interventions to improve time-to-treatment.

Abstract NS3: Nurse Led Interventions Improve the Timeliness of Blood Pressure Reduction in Patients Presenting With Acute Nontraumatic Intracerebral Hemorrhage

Introduction: The 2022 AHA/ASA Guidelines for Intracerebral Hemorrhage (ICH) recommend initiating treatment and lowering blood pressure (BP) within 2 hours of ICH onset and reaching the target systolic BP of 130-150mmHg within one hour of treatment initiation. This study evaluates the effectiveness of nursing education at a Comprehensive Stroke Center (CSC) on improving the timeliness of BP medication administration and BP reduction in ICH patients. Methods: Emergency Department (ED) code stroke patients with a diagnosis of ICH were included in the analysis from 6/2022-12/2022 (pre-intervention) and 1/2023-6/2023 (post-intervention). Guideline based education regarding the importance of timely medication administration was provided in nursing huddles. Nurse to patient ratios were changed to 1:1 until goal BP achieved. BP medications were also placed in the CT scanner pyxis for immediate access. Baseline demographics, NIHSS, ICH score, and door to blood pressure reduction related time metrics were collected. Data were analyzed using R package. Results: 34 patients were analyzed, 12 (35%) pre and 22 (65%) post-intervention. Patient demographics and characteristics were not different between both groups (Table 1). Time from first BP medication order to BP in range improved: 62(46.7-80) vs 43(33-52.3) mins p=0.02. In addition, the time from door to Systolic BP 130-150mmHg improved 81 (68.5-91.3) vs 56 (37.38-73.5) mins p=0.02 (Table 2). Conclusion: Guideline based education is effective in promoting nursing-led interventions to achieve timely BP reduction of ICH patients to the target goal of 130-150 mmHg.