Severity of leukoaraiosis correlates with clinical outcome after ischemic stroke

Are we ready to cure post-stroke cognitive impairment? Many key prerequisites can be achieved quickly and easily

PURPOSE

Post-stroke (PS) cognitive impairment (CI) is frequent and its devastating functional and vital consequences are well known. Despite recent guidelines, they are still largely neglected. A large number of recent studies have re-examined the epidemiology, diagnosis, imaging determinants and management of PSCI. The aim of this update is to determine whether these new data answer the questions that are essential to reducing PSCI, the unmet needs, and steps still to be taken.

METHODS

Literature review of stroke unit-era studies examining key steps in the management of PSCI: epidemiology and risk factors, diagnosis (cognitive profile and assessments), imaging determinants (quantitative measures, voxelwise localization, the disconnectome and associated Alzheimer's disease [AD]) and treatment (secondary prevention, symptomatic drugs, rehabilitation and noninvasive brain stimulation) of PSCI.

FINDINGS

(1) the prevalence of PSCI of approximately 50% is probably underestimated; (2) the sensitivity of screening tests should be improved to detect mild PSCI; (3) comprehensive assessment is now well-defined and should include apathy; (4) easily available factors can identify patients at high risk of PSCI; (5) key imaging determinants are the location and volume of the lesion and the resulting disconnection, associated AD and brain atrophy; WMH, ePVS, microhemorrhages, hemosiderosis, and cortical microinfarcts may contribute to cognitive impairment but are more likely to be markers of brain vulnerability or associated AD that reduce PS recovery; (6) remote and online assessment is a promising approach for selected patients; (7) secondary stroke prevention has not been proven to prevent PSCI; (8) symptomatic drugs are ineffective in treating PSCI and apathy; (9) in addition to cognitive rehabilitation, the benefits of training platforms and computerized training are yet to be documented; (10) the results and the magnitude of improvement of noninvasive brain stimulation, while very promising, need to be substantiated by large, high-quality, sham-controlled RCTs.

DISCUSSION AND CONCLUSION

These major advances pave the way for the reduction of PSCI. They include (1) the development of more sensitive screening tests applicable to all patients and (2) online remote assessment; crossvalidation of (3) clinical and (4) imaging factors to (5) identify patients at risk, as well as (6) factors that prompt a search for associated AD; (7) the inclusion of cognitive outcome as a secondary endpoint in acute and secondary stroke prevention trials; and (8) the validation of the benefit of noninvasive brain stimulation through high-quality, randomized, sham-controlled trials. Many of these objectives can be rapidly and easily attained.

Predictors of Good Functional Outcome in Patients with Tandem Occlusion After Revascularization Treatment: Single-Center Experience with 12-Month Follow-Up

OBJECTIVE

The optimal management and procedural strategy for tandem occlusion (TO) in acute ischemic stroke are still unclear, as is the long-term outcome of these patients. The aim of this study was to evaluate predictors of good functional outcome in patients with TO through the analysis of demographics, clinical, and radiological data with a 1-year follow-up.

METHODS

We collected data on 100 patients with TO who underwent revascularization treatments in our comprehensive stroke center. We divided patients into 2 groups: those with good functional outcome, defined as a modified Rankin Scale 0-2, and those with poor functional outcome, defined as a modified Rankin Scale 3-6 at 3, 6, and 12-month follow-up. Moreover, we investigated which variables were able to influence mortality.

RESULTS

At multivariate analysis, endovascular treatment with mechanical thrombectomy combined with emergent cervical carotid artery stenting was an independent predictor of good functional outcome at 6 and 12 months (adjusted odds ratio [aOR] 4.3, confidence interval [CI] 1.49-12.31, P = 0.007) (aOR 3.5, CI 1.25-9.61, P = 0.017) and was associated with a lower rate of mortality at 3 and 6 months follow-up (aOR 0.14, CI 0.04-0.57, P = 0.006 and aOR 0.296, CI 0.97-0.902, P = 0.032, respectively). Furthermore, smoking habit was associated with a better outcome at 3-month follow-up (aOR 10.7, CI 2.2-51.6, P = 0.003) but not at 6- and 12-month.

CONCLUSIONS

Our research, conducted in a small sample size of patients with acute ischemic stroke due to TO of anterior circulation, found that acute stent placement seems to be safe, improving clinical outcome, and it is associated with low rate of mortality at long-term follow-up.

Aldosterone is Associated With New-onset Cerebrovascular Events in Patients With Hypertension and White Matter Lesions: A Cohort Study

OBJECTIVE

White matter lesions (WMLs) increase the risk of stroke, stroke recurrence, and death. Higher plasma aldosterone concentration (PAC) increases the risk of stroke, acute myocardial infarction, and hypertension. The objective is to evaluate the relationship between PAC and cerebrovascular events in patients with hypertension and WMLs.

METHODS

We conducted a retrospective cohort study that included 1041 participants hospitalized. The outcome was new-onset cerebrovascular events including intracerebral hemorrhage and stroke. A Cox regression model was used to evaluate the relationship between baseline PAC and the risk of cerebrovascular events.

RESULTS

The mean age of participants was 60.9 ± 10.2 years and 565 (53.4%) were males. The median follow-up duration was 42 months (interquartile range: 25-67), and 92 patients experienced new-onset cerebrovascular events. In a multivariate-adjusted model, with PAC as a continuous variable, higher PAC increased the risk of cerebrovascular events; patient risk increased per 1 (hazard ratio [HR: 1.03], 95% confidence interval [CI]: 1.01-1.06, P < .01), per 5 (HR: 1.17, 95% CI: 1.06-1.31, P < .01), and per 10 ng/dL (HR: 1.41, 95%: 1.14-1.75, P < .01) increase in PAC. When PAC was expressed as a categorical variable (quartile: Q1-Q4), patients in Q4 (HR: 2.12, 95% CI: 1.18-3.79, P < .05) exhibited an increased risk of cerebrovascular events compared to Q1. Restrictive spline regression showed a linear association between PAC and the risk of new-onset cerebrovascular events after adjusting for all possible variables.

CONCLUSIONS

Our study identified a linear association between PAC and the risk of new-onset cerebrovascular events in patients with hypertension and WMLs.

Regional brain aging: premature aging of the domain general system predicts aphasia severity

Premature brain aging is associated with poorer cognitive reserve and lower resilience to injury. When there are focal brain lesions, brain regions may age at different rates within the same individual. Therefore, we hypothesize that reduced gray matter volume within specific brain systems commonly associated with language recovery may be important for long-term aphasia severity. Here we show that individuals with stroke aphasia have a premature brain aging in intact regions of the lesioned hemisphere. In left domain-general regions, premature brain aging, gray matter volume, lesion volume and age were all significant predictors of aphasia severity. Increased brain age following a stroke is driven by the lesioned hemisphere. The relationship between brain age in left domain-general regions and aphasia severity suggests that degradation is possible to specific brain regions and isolated aging matters for behavior.

A promising frontier: targeting NETs for stroke treatment breakthroughs

Stroke is a prevalent global acute cerebrovascular condition, with ischaemic stroke being the most frequently occurring type. After a stroke, neutrophils accumulate in the brain and subsequently generate and release neutrophil extracellular traps (NETs). The accumulation of NETs exacerbates the impairment of the blood‒brain barrier (BBB), hampers neovascularization, induces notable neurological deficits, worsens the prognosis of stroke patients, and can facilitate the occurrence of t-PA-induced cerebral haemorrhage subsequent to ischaemic stroke. Alternative approaches to pharmacological thrombolysis or endovascular thrombectomy are being explored, and targeting NETs is a promising treatment that warrants further investigation.

Subtle white matter intensity changes on fluid-attenuated inversion recovery imaging in patients with ischaemic stroke

Leukoaraiosis is a neuroimaging marker of small-vessel disease that is characterized by high signal intensity on fluid-attenuated inversion recovery MRI. There is increasing evidence from pathology and neuroimaging suggesting that the structural abnormalities that characterize leukoaraiosis are actually present within regions of normal-appearing white matter, and that the underlying pathophysiology of white matter damage related to small-vessel disease involves blood-brain barrier damage. In this study, we aim to verify whether leukoaraiosis is associated with elevated signal intensity on fluid-attenuated inversion recovery imaging, a marker of brain tissue free-water accumulation, in normal-appearing white matter. We performed a cross-sectional study of adult patients admitted to our hospital with a diagnosis of acute ischaemic stroke or transient ischaemic attack. Leukoaraiosis was segmented using a semi-automated method involving manual outlining and signal thresholding. White matter regions were segmented based on the probabilistic tissue maps from the International Consortium for Brain Mapping 152 atlas. Also, normal-appearing white matter was further segmented based on voxel distance from leukoaraiosis borders, resulting in five normal-appearing white matter strata at increasing voxel distances from leukoaraiosis. The relationship between mean normalized fluid-attenuated inversion recovery signal intensity on normal-appearing white matter and leukoaraiosis volume was studied in a multivariable statistical analysis using linear mixed modelling, having normal-appearing white matter strata as a clustering variable. One hundred consecutive patients meeting inclusion and exclusion criteria were selected for analysis (53% female, mean age 68 years). Mean normalized fluid-attenuated inversion recovery signal intensity on normal-appearing white matter was higher in the vicinity of leukoaraiosis and progressively lower at increasing distances from leukoaraiosis. In a multivariable analysis, the mean normalized fluid-attenuated inversion recovery signal intensity on normal-appearing white matter was positively associated with leukoaraiosis volume and age (B = 0.025 for each leukoaraiosis quartile increase; 95% confidence interval 0.019-0.030). This association was found similarly across normal-appearing white matter strata. Voxel maps of the mean normalized fluid-attenuated inversion recovery signal intensity on normal-appearing white matter showed an increase in signal intensity that was not adjacent to leukoaraiosis regions. Our results show that normal-appearing white matter exhibits subtle signal intensity changes on fluid-attenuated inversion recovery imaging that are related to leukoaraiosis burden. These results suggest that diffuse free-water accumulation is likely related to the aetiopathogenic processes underlying the development of white matter damage related to small-vessel disease.

Scaling behaviours of deep learning and linear algorithms for the prediction of stroke severity

Deep learning has allowed for remarkable progress in many medical scenarios. Deep learning prediction models often require 105-107 examples. It is currently unknown whether deep learning can also enhance predictions of symptoms post-stroke in real-world samples of stroke patients that are often several magnitudes smaller. Such stroke outcome predictions however could be particularly instrumental in guiding acute clinical and rehabilitation care decisions. We here compared the capacities of classically used linear and novel deep learning algorithms in their prediction of stroke severity. Our analyses relied on a total of 1430 patients assembled from the MRI-Genetics Interface Exploration collaboration and a Massachusetts General Hospital-based study. The outcome of interest was National Institutes of Health Stroke Scale-based stroke severity in the acute phase after ischaemic stroke onset, which we predict by means of MRI-derived lesion location. We automatically derived lesion segmentations from diffusion-weighted clinical MRI scans, performed spatial normalization and included a principal component analysis step, retaining 95% of the variance of the original data. We then repeatedly separated a train, validation and test set to investigate the effects of sample size; we subsampled the train set to 100, 300 and 900 and trained the algorithms to predict the stroke severity score for each sample size with regularized linear regression and an eight-layered neural network. We selected hyperparameters on the validation set. We evaluated model performance based on the explained variance (R2) in the test set. While linear regression performed significantly better for a sample size of 100 patients, deep learning started to significantly outperform linear regression when trained on 900 patients. Average prediction performance improved by ∼20% when increasing the sample size 9× [maximum for 100 patients: 0.279 ± 0.005 (R2, 95% confidence interval), 900 patients: 0.337 ± 0.006]. In summary, for sample sizes of 900 patients, deep learning showed a higher prediction performance than typically employed linear methods. These findings suggest the existence of non-linear relationships between lesion location and stroke severity that can be utilized for an improved prediction performance for larger sample sizes.

Correlation between body composition and white matter hyperintensity in patients with acute ischemic stroke

White matter hyperintensity (WMH) burden is associated with a higher risk of ischemic stroke. The relationship between WMH and obesity is somewhat controversial which might be interfered by different body composition such as skeletal muscle, fat and bone density. However, few researchers have evaluated the relationship between WMH burden and disaggregated body constituents in acute ischemic stroke (AIS) patients systematically. A total of 352 AIS patients were enrolled in this study. The subcutaneous adipose tissue, erector spinae muscle area and bone density were evaluated on the computed tomography scanning. The burden of WMH was evaluated using the Fazekas scale based on the fluid-attenuated inversion recovery sequence. The severity of overall WMH was defined as none-mild WMH (total Fazekas score 0-2) or moderate-severe WMH (total Fazekas score 3-6). Based on the severity of periventricular WMH (P-WMH) and deep WMH, patients were categorized into either a none-mild (Fazekas score 0-1) group or a moderate-severe (Fazekas score 2-3) group. We found that patients with moderate-severe WMH showed lower bone density and smaller erector spinae muscle area and subcutaneous adipose tissue than none-mild. The logistic regression analysis showed that the bone density was independently associated with moderate-severe overall WMH (odds radio = 0.98, 95% confidence interval, 0.972-0.992, P < .001) and similar results were found in the analyses according to P-WMH (odds radio = 0.98, 95% confidence interval, 0.972-0.992, P < .001). These findings suggest that among the AIS body composition, the bone density is independently associated with the severity of overall WMH and P-WMH.

Longitudinal Progression of White Matter Hyperintensity Severity in Chronic Stroke Aphasia

Objective

To determine whether longitudinal progression of small vessel disease in chronic stroke survivors is associated with longitudinal worsening of chronic aphasia severity.

Design

A longitudinal retrospective study. Severity of white matter hyperintensities (WMHs) as a marker for small vessel disease was assessed on fluid-attenuated inversion recovery (FLAIR) scans using the Fazekas scale, with ratings for deep WMHs (DWMHs) and periventricular WMHs (PVHs).

Setting

University research laboratories.

Participants

This study includes data from 49 chronic stroke survivors with aphasia (N=49; 15 women, 34 men, age range=32-81 years, >6 months post-stroke, stroke type: [46 ischemic, 3 hemorrhagic], community dwelling). All participants completed the Western Aphasia Battery-Revised (WAB) and had FLAIR scans at 2 timepoints (average years between timepoints: 1.87 years, SD=3.21 years).

Interventions

Not applicable.

Main Outcome Measures

Change in white matter hyperintensity severity (calculated using the Fazekas scale) and change in aphasia severity (difference in Western Aphasia Battery scores) were calculated between timepoints. Separate stepwise regression models were used to identify predictors of WMH severity change, with lesion volume, age, time between timepoints, body mass index (BMI), and presence of diabetes as independent variables. Additional stepwise regression models investigated predictors of change in aphasia severity, with PVH change, DWMH change, lesion volume, time between timepoints, and age as independent predictors.

Results

22.5% of participants (11/49) had increased WMH severity. Increased BMI was associated with increases in PVH severity (P=.007), whereas the presence of diabetes was associated with increased DWMH severity (P=.002). Twenty-five percent of participants had increased aphasia severity which was significantly associated with increased severity of PVH (P<.001, 16.8% variance explained).

Conclusion

Increased small vessel disease burden is associated with contributing to chronic changes in aphasia severity. These findings support the idea that good cardiovascular risk factor control may play an important role in the prevention of long-term worsening of aphasic symptoms.

Leukoaraiosis Is Not Associated With Recovery From Aphasia in the First Year After Stroke

After a stroke, individuals with aphasia often recover to a certain extent over time. This recovery process may be dependent on the health of surviving brain regions. Leukoaraiosis (white matter hyperintensities on MRI reflecting cerebral small vessel disease) is one indication of compromised brain health and is associated with cognitive and motor impairment. Previous studies have suggested that leukoaraiosis may be a clinically relevant predictor of aphasia outcomes and recovery, although findings have been inconsistent. We investigated the relationship between leukoaraiosis and aphasia in the first year after stroke. We recruited 267 patients with acute left hemispheric stroke and coincident fluid attenuated inversion recovery MRI. Patients were evaluated for aphasia within 5 days of stroke, and 174 patients presented with aphasia acutely. Of these, 84 patients were evaluated at ∼3 months post-stroke or later to assess longer-term speech and language outcomes. Multivariable regression models were fit to the data to identify any relationships between leukoaraiosis and initial aphasia severity, extent of recovery, or longer-term aphasia severity. We found that leukoaraiosis was present to varying degrees in 90% of patients. However, leukoaraiosis did not predict initial aphasia severity, aphasia recovery, or longer-term aphasia severity. The lack of any relationship between leukoaraiosis severity and aphasia recovery may reflect the anatomical distribution of cerebral small vessel disease, which is largely medial to the white matter pathways that are critical for speech and language function.

Small vessel disease is associated with later onset of major adverse cardiovascular events after acute cervicocerebral artery dissection

BACKGROUND

Cerebral small vessel disease (CSVD) is common among the elderly and has been associated with an increased risk of major adverse cardiac events (MACE) and increased risk of long-term disability. Little is known whether CSVD affects outcomes after cervicocerebral artery dissection (CAD), which predominantly affects younger patients. Specifically, there is a paucity as to whether CSVD increases the risk of MACE after CAD and whether this risk is different for early versus late events.

METHODS

We retrospectively analyzed 140 consecutive patients with acute CAD. We determined CSVD on MRI using the STRIVE criteria and calculated the CSVD sum score based on the individual CSVD components. For statistical analysis the CSVD burden was dichotomized to mild (score 0-1) versus severe (score 2-4). The primary outcome of interest was the 6-month MACE risk. Secondary outcomes of interest were early versus late MACE, stroke at presentation, and good 90-day outcome (modified Rankin Scale score 0-2).

RESULTS

There was no difference in overall MACE between subjects when stratified by CSVD burden (10.1% versus 9.8%, Log-rank P = 0.953). We found that patients with severe CSVD had significantly more late MACE as compared to mild CSVD (9.8% versus 1.1%, P = 0.024). There was no significant difference in the prevalence of stroke at the time of CAD diagnosis (50.6% versus 47.1%, P = 0.690) and the 90-day disability-free survival in subjects with mild versus severe CSVD (93.7% versus 91.7%, P = 0.729).

CONCLUSION

Severe CSVD burden was associated with a significantly greater risk of late MACE. CSVD assessment in CAD patients may aid risk stratification and treatment optimization.

MRI-based risk stratification for recurrent ischemic stroke in embolic stroke of undetermined source

OBJECTIVE

Leukoaraiosis and other brain MRI-assessed parameters were shown to be associated with recurrent stroke in this population. We aimed to develop an MRI-based predictive tool for risk stratification of ESUS patients.

METHODS

We retrospectively assessed consecutive patients who were diagnosed with ESUS and underwent brain MRI and performed a multivariable analysis with the outcome of recurrent stroke/TIA. Based on the coefficient of each covariate, we generated an integer-based point scoring system. The discrimination and calibration of the score were assessed using the area under the receiver operator characteristic curve, net reclassification improvement, integrated discrimination improvement, calibration curve, and decision curve analysis. Also, we compared the new score with a previously published score (ALM score).

RESULTS

Among 176 patients followed for an overall period of 902.3 patient-years (median of 74 months), there were 39 recurrent ischemic stroke/TIAs (4.32 per 100 patient-years). Fazekas score (HR: 1.26, 95% CI: 1.03-1.54), enlarged perivascular space (EPVS) (HR: 2.76, 95% CI: 1.12-6.17), NIHSS at admission (HR: 1.11, 95% CI: 1.02-1.18), and infarct subtypes (HR: 2.88, 95% CI: 1.34-6.17) were associated with recurrent stroke/TIA. Accordingly, a score (FENS score) was developed with AUC-ROC values of 0.863, 0.788, and 0.858 for 1, 3, and 5 years, respectively. These were significantly better than the AUC-ROC of ALM score (0.635, 0.695, and 0.705, respectively). The FENS score exhibited better calibration and discrimination ability than the ALM score (Hosmer-Lemeshow test χ2 : 4.402, p = 0.819).

CONCLUSION

The MRI-based FENS score can provide excellent predictive performance for recurrent stroke/TIA and may assist in risk stratification of ESUS patients.

Interpretable machine learning for predicting 28-day all-cause in-hospital mortality for hypertensive ischemic or hemorrhagic stroke patients in the ICU: a multi-center retrospective cohort study with internal and external cross-validation

Background

Timely and accurate outcome prediction plays a critical role in guiding clinical decisions for hypertensive ischemic or hemorrhagic stroke patients admitted to the ICU. However, interpreting and translating the predictive models into clinical applications are as important as the prediction itself. This study aimed to develop an interpretable machine learning (IML) model that accurately predicts 28-day all-cause mortality in hypertensive ischemic or hemorrhagic stroke patients.

Methods

A total of 4,274 hypertensive ischemic or hemorrhagic stroke patients admitted to the ICU in the USA from multicenter cohorts were included in this study to develop and validate the IML model. Five machine learning (ML) models were developed, including artificial neural network (ANN), gradient boosting machine (GBM), eXtreme Gradient Boosting (XGBoost), logistic regression (LR), and support vector machine (SVM), to predict mortality using the MIMIC-IV and eICU-CRD database in the USA. Feature selection was performed using the Least Absolute Shrinkage and Selection Operator (LASSO) algorithm. Model performance was evaluated based on the area under the curve (AUC), accuracy, positive predictive value (PPV), and negative predictive value (NPV). The ML model with the best predictive performance was selected for interpretability analysis. Finally, the SHapley Additive exPlanations (SHAP) method was employed to evaluate the risk of all-cause in-hospital mortality among hypertensive ischemic or hemorrhagic stroke patients admitted to the ICU.

Results

The XGBoost model demonstrated the best predictive performance, with the AUC values of 0.822, 0.739, and 0.700 in the training, test, and external cohorts, respectively. The analysis of feature importance revealed that age, ethnicity, white blood cell (WBC), hyperlipidemia, mean corpuscular volume (MCV), glucose, pulse oximeter oxygen saturation (SpO2), serum calcium, red blood cell distribution width (RDW), blood urea nitrogen (BUN), and bicarbonate were the 11 most important features. The SHAP plots were employed to interpret the XGBoost model.

Conclusions

The XGBoost model accurately predicted 28-day all-cause in-hospital mortality among hypertensive ischemic or hemorrhagic stroke patients admitted to the ICU. The SHAP method can provide explicit explanations of personalized risk prediction, which can aid physicians in understanding the model.

Association between National Institutes of Health Stroke Scale and Functional Independence Measure scores in patients with ischemic stroke from convalescent rehabilitation outcomes

We investigated the associations among neurological severity, activities of daily living (ADLs), and clinical factors in patients with ischemic stroke in convalescent rehabilitation outcome. The study sample included 723 patients with ischemic stroke (484 men and 239 women; mean age, 73.2 ± 8.5 years) for inpatient convalescent rehabilitation. National Institutes of Health Stroke Scale (NIHSS) was used to measure the neurological severity, and Functional Independence Measure (FIM) was used to assess ADLs at discharge. Leukoaraiosis was graded based on periventricular hyperintensity (PVH) and deep white matter hyperintensity (DWMH) on magnetic resonance imaging. The correlations between NIHSS scores and total FIM scores were significant but relatively mild (r = -0.684, P < 0.001). Multiple regression analysis revealed that age and PVH grade significantly decreased their total FIM scores and affected the discrepancies between NIHSS scores at discharge (P < 0.001), but DWMH scores did not affect these results. Factors such as positive history of heart disease (P = 0.008) and bilateral infarction (P = 0.038) additionally decreased their total FIM scores and affected the discrepancies between NIHSS scores. These findings suggest that age, PVH, history of heart disease positive, and bilateral infarction in patients with ischemic stroke affected their performance of ADLs and the discrepancies between their neurological severities in convalescent rehabilitation outcomes, probably because the pathophysiological background of leukoaraiosis and these factors strongly decrease their ADL performance in post-phase ischemic stroke.

A Nomogram for Predicting the Recurrence of Acute Non-Cardioembolic Ischemic Stroke: A Retrospective Hospital-Based Cohort Analysis

Non-cardioembolic ischemic stroke (IS) is the predominant subtype of IS. This study aimed to construct a nomogram for recurrence risks in patients with non-cardioembolic IS in order to maximize clinical benefits. From April 2015 to December 2019, data from consecutive patients who were diagnosed with non-cardioembolic IS were collected from Lanzhou University Second Hospital. The least absolute shrinkage and selection operator (LASSO) regression analysis was used to optimize variable selection. Multivariable Cox regression analyses were used to identify the independent risk factors. A nomogram model was constructed using the "rms" package in R software via multifactor Cox regression. The accuracy of the model was evaluated using the receiver operating characteristic (ROC), calibration curve, and decision curve analyses (DCA). A total of 729 non-cardioembolic IS patients were enrolled, including 498 (68.3%) male patients and 231 (31.7%) female patients. Among them, there were 137 patients (18.8%) with recurrence. The patients were randomly divided into training and testing sets. The Kaplan-Meier survival analysis of the training and testing sets consistently revealed that the recurrence rates in the high-risk group were significantly higher than those in the low-risk group (p < 0.01). Moreover, the receiver operating characteristic curve analysis of the risk score demonstrated that the area under the curve was 0.778 and 0.760 in the training and testing sets, respectively. The nomogram comprised independent risk factors, including age, diabetes, platelet-lymphocyte ratio, leukoencephalopathy, neutrophil, monocytes, total protein, platelet, albumin, indirect bilirubin, and high-density lipoprotein. The C-index of the nomogram was 0.752 (95% CI: 0.705~0.799) in the training set and 0.749 (95% CI: 0.663~0.835) in the testing set. The nomogram model can be used as an effective tool for carrying out individualized recurrence predictions for non-cardioembolic IS.

Association between Citrullinated Histone H3 and White Matter Lesions Burden in Patients with Ischemic Stroke

INTRODUCTION

Neutrophil extracellular traps play a role in the pathophysiology of stroke and are associated with severity and mortality. We aimed to investigate whether the citrullinated histone H3 (CitH3), a biomarker for neutrophil extracellular traps formation, is associated with the white matter lesion (WML) burden in ischemic stroke patients.

METHODS

Between September 2021 and April 2022, 322 patients were enrolled in this prospective observational cohort study. Serum CitH3 levels were measured after admission using an enzyme-linked immunosorbent assay. WMLs severity was graded according to the Fazekas scale and conceptually defined as mild (total Fazekas score 0-2) and severe (total Fazekas score 3-6). We used multivariable regression models to determine the relationship between CitH3 concentrations and the severity of WMLs burden.

RESULTS

One-hundred and forty-eight (46.0%) patients were diagnosed with severe WMLs burden after admission. Increased CitH3 levels (first quartile vs. fourth quartile of H3Cit, odds ratio, 3.311, 95% confidence interval, 1.336-8.027; p = 0.011) were independently associated with a greater WML burden in the fully adjusted multivariable model. Similar results were found when the H3Cit was analyzed as a continuous variable. Furthermore, the multiple-adjusted spline regression model showed a linear association between H3Cit levels and severe WMLs (P = 0.001 for linearity).

CONCLUSIONS

In the present study, increased CitH3 levels were positively associated with extensive WMLs in ischemic stroke patients, indicating a role of neutrophil extracellular traps formation in the pathogenesis of WMLs.

High Mean Platelet Volume Is Associated with Cerebral White Matter Hyperintensities in Non-Stroke Individuals

PURPOSE

The mean platelet volume (MPV) is regarded as a marker for thrombosis, atherosclerosis, and inflammation in various vascular diseases. However, it still remains unclear whether plasma MPV is associated with cerebral white matter hyperintensities (WMH) and cerebral microvascular pathology in the elderly population.

MATERIALS AND METHODS

We examined whether MPV level is associated with the presence of cerebral WMH on brain magnetic resonance imaging from 870 non-stroke outpatient subjects. The subjects were divided into three groups according to the consecutive level of MPV (low T1, middle T2, and high T3 MPV tertile groups). To determine the association of MPV levels with the WMH, logistic regression and receiver operating characteristic curve analyses were conducted.

RESULTS

Subjects with higher MPV level were older and more likely to have hypertension, diabetes mellitus, and low renal function. Cerebral WMH were more prevalent in subjects with higher MPV level. After adjusting for confounding factors, moderate to severe cerebral WMH were significantly associated with high MPV tertile level. This association remained significant after adjusting for other cerebral vascular pathologies. T2 [odds ratio (OR): 1.49, 95% confidence interval (CI): 1.03-2.15] and T3 MPV tertile groups (OR: 1.51, 95%CI: 1.04-2.20) had more cerebral WMH lesions compared to T1 MPV tertile group. In addition, the subjects with higher Fazekas scores showed higher MPV level (p=0.020).

CONCLUSION

We found that high MPV level is independently associated with cerebral WMH. This result suggests that platelet activation plays a role in the development of cerebral WMH.

Association of cerebral white matter hyperintensities with coronary artery calcium in a healthy population: a cross-sectional study

In brain magnetic resonance imaging (MRI), white matter hyperintensity (WMH) is a commonly encountered finding and is known to reflect cerebral small vessel disease. The aim of our study was to investigate the association of coronary artery calcium (CAC) with WMH and elucidate the relationship between WMH and atherosclerotic risk factors in a large-scale healthy population. This retrospective study included 1337 individuals who underwent brain MRI and CAC scoring computed tomography at healthcare centers affiliated with a tertiary hospital. Cerebral WMH was defined as Fazekas score greater than 2 on brain MRI. Intracranial artery stenosis (ICAS) was also assessed and determined to be present when stenosis was more than 50% on angiography. The associations of risk factors, CAC score, and ICAS with cerebral WMH were assessed by multivariable regression analysis. In multivariable analysis, categories of higher CAC scores showed increased associations with both periventricular and deep WMHs in a dose-dependent relationship. The presence of ICAS was also significantly related to cerebral WMH, and among the clinical variables, age and hypertension were independent risk factors. In conclusion, CAC showed a significant association with cerebral WMH in a healthy population, which might provide evidence for referring to the CAC score to identify individuals with risk of cerebral WMH.

The contribution of white matter pathology, hypoperfusion, lesion load, and stroke recurrence to language deficits following acute subcortical left hemisphere stroke

Aphasia, the loss of language ability following damage to the brain, is among the most disabling and common consequences of stroke. Subcortical stroke, occurring in the basal ganglia, thalamus, and/or deep white matter can result in aphasia, often characterized by word fluency, motor speech output, or sentence generation impairments. The link between greater lesion volume and acute aphasia is well documented, but the independent contributions of lesion location, cortical hypoperfusion, prior stroke, and white matter degeneration (leukoaraiosis) remain unclear, particularly in subcortical aphasia. Thus, we aimed to disentangle the contributions of each factor on language impairments in left hemisphere acute subcortical stroke survivors. Eighty patients with acute ischemic left hemisphere subcortical stroke (less than 10 days post-onset) participated. We manually traced acute lesions on diffusion-weighted scans and prior lesions on T2-weighted scans. Leukoaraiosis was rated on T2-weighted scans using the Fazekas et al. (1987) scale. Fluid-attenuated inversion recovery (FLAIR) scans were evaluated for hyperintense vessels in each vascular territory, providing an indirect measure of hypoperfusion in lieu of perfusion-weighted imaging. We found that language performance was negatively correlated with acute/total lesion volumes and greater damage to substructures of the deep white matter and basal ganglia. We conducted a LASSO regression that included all variables for which we found significant univariate relationships to language performance, plus nuisance regressors. Only total lesion volume was a significant predictor of global language impairment severity. Further examination of three participants with severe language impairments suggests that their deficits result from impairment in domain-general, rather than linguistic, processes. Given the variability in language deficits and imaging markers associated with such deficits, it seems likely that subcortical aphasia is a heterogeneous clinical syndrome with distinct causes across individuals.

Association of Stroke Lesion Pattern and White Matter Hyperintensity Burden With Stroke Severity and Outcome

BACKGROUND AND OBJECTIVES

To examine whether high white matter hyperintensity (WMH) burden is associated with greater stroke severity and worse functional outcomes in lesion pattern-specific ways.

METHODS

MR neuroimaging and NIH Stroke Scale data at index stroke and the modified Rankin Scale (mRS) score at 3-6 months after stroke were obtained from the MRI-Genetics Interface Exploration study of patients with acute ischemic stroke (AIS). Individual WMH volume was automatically derived from fluid-attenuated inversion recovery images. Stroke lesions were automatically segmented from diffusion-weighted imaging (DWI) images, parcellated into atlas-defined brain regions and further condensed to 10 lesion patterns via machine learning-based dimensionality reduction. Stroke lesion effects on AIS severity and unfavorable outcomes (mRS score >2) were modeled within purpose-built Bayesian linear and logistic regression frameworks. Interaction effects between stroke lesions and a high vs low WMH burden were integrated via hierarchical model structures. Models were adjusted for age, age2, sex, total DWI lesion and WMH volumes, and comorbidities. Data were split into derivation and validation cohorts.

RESULTS

A total of 928 patients with AIS contributed to acute stroke severity analyses (age: 64.8 [14.5] years, 40% women) and 698 patients to long-term functional outcome analyses (age: 65.9 [14.7] years, 41% women). Stroke severity was mainly explained by lesions focused on bilateral subcortical and left hemispherically pronounced cortical regions across patients with both a high and low WMH burden. Lesions centered on left-hemispheric insular, opercular, and inferior frontal regions and lesions affecting right-hemispheric temporoparietal regions had more pronounced effects on stroke severity in case of high compared with low WMH burden. Unfavorable outcomes were predominantly explained by lesions in bilateral subcortical regions. In difference to the lesion location-specific WMH effects on stroke severity, higher WMH burden increased the odds of unfavorable outcomes independent of lesion location.

DISCUSSION

Higher WMH burden may be associated with an increased stroke severity in case of stroke lesions involving left-hemispheric insular, opercular, and inferior frontal regions (potentially linked to language functions) and right-hemispheric temporoparietal regions (potentially linked to attention). Our findings suggest that patients with specific constellations of WMH burden and lesion locations may have greater benefits from acute recanalization treatments. Future clinical studies are warranted to systematically assess this assumption and guide more tailored treatment decisions.

Diagnostic performance of deep learning-based automatic white matter hyperintensity segmentation for classification of the Fazekas scale and differentiation of subcortical vascular dementia

Purpose

To validate the diagnostic performance of commercially available, deep learning-based automatic white matter hyperintensity (WMH) segmentation algorithm for classifying the grades of the Fazekas scale and differentiating subcortical vascular dementia.

Methods

This retrospective, observational, single-institution study investigated the diagnostic performance of a deep learning-based automatic WMH volume segmentation to classify the grades of the Fazekas scale and differentiate subcortical vascular dementia. The VUNO Med-DeepBrain was used for the WMH segmentation system. The system for segmentation of WMH was designed with convolutional neural networks, in which the input image was comprised of a pre-processed axial FLAIR image, and the output was a segmented WMH mask and its volume. Patients presented with memory complaint between March 2017 and June 2018 were included and were split into training (March 2017–March 2018, n = 596) and internal validation test set (April 2018–June 2018, n = 204).

Results

Optimal cut-off values to categorize WMH volume as normal vs. mild/moderate/severe, normal/mild vs. moderate/severe, and normal/mild/moderate vs. severe were 3.4 mL, 9.6 mL, and 17.1 mL, respectively, and the AUC were 0.921, 0.956 and 0.960, respectively. When differentiating normal/mild vs. moderate/severe using WMH volume in the test set, sensitivity, specificity, and accuracy were 96.4%, 89.9%, and 91.7%, respectively. For distinguishing subcortical vascular dementia from others using WMH volume, sensitivity, specificity, and accuracy were 83.3%, 84.3%, and 84.3%, respectively.

Conclusion

Deep learning-based automatic WMH segmentation may be an accurate and promising method for classifying the grades of the Fazekas scale and differentiating subcortical vascular dementia.

Exploring biomarkers of processing speed and executive function: The role of the anterior thalamic radiations

INTRODUCTION

Processing speed and executive function are often impaired after stroke and in typical aging. However, there are no reliable neurological markers of these cognitive impairments. The trail making test (TMT) is a common index of processing speed and executive function. Here, we tested candidate MRI markers of TMT performance in a cohort of older adults and individuals with chronic stroke.

METHODS

In 61 older adults and 32 individuals with chronic stroke, we indexed white matter structure with region-specific lesion load (of white matter hyperintensities (WMHs) and stroke lesions) and diffusion tensor imaging (DTI) from four regions related to TMT performance: the anterior thalamic radiations (ATR), superior longitudinal fasciculus (SLF), forceps minor, and cholinergic pathways. Regression modelling was used to identify the marker(s) that explained the most variance in TMT performance.

RESULTS

DTI metrics of the ATR related to processing speed in both the older adult (TMT A: β = -3.431, p < 0.001) and chronic stroke (TMT A: β = 11.282, p < 0.001) groups. In the chronic stroke group executive function was best predicted by a combination of ATR and forceps minor DTI metrics (TMT B: _adjustedR² = 0.438, p < 0.001); no significant predictors of executive function (TMT B) emerged in the older adult group. No imaging metrics related to set shifting (TMT B-A). Regional DTI metrics predicted TMT performance above and beyond whole-brain stroke and WMH volumes and removing whole-brain lesion volumes improved model fits.

CONCLUSIONS

In this comprehensive assessment of candidate imaging markers, we demonstrate an association between ATR microstructure and processing speed and executive function performance. Regional DTI metrics provided better predictors of cognitive performance than whole-brain lesion volumes or regional lesion load, emphasizing the importance of lesion location in understanding cognition. We propose ATR DTI metrics as novel candidate imaging biomarker of post-stroke cognitive impairment.

Ischemic stroke demographics, clinical features and scales and their correlations: an exploratory study from Jordan

Aims:

The authors aimed to assess the ischemic stroke risk factors and scales.

Materials & methods:

A retrospective cohort study was conducted on patients with acute ischemic stroke (from January 2017 to December 2018). The scores of the National Institutes of Health Stroke Scale (NIHSS) at admission and discharge and of the modified Rankin Scale (mRS) and Barthel Index (BI) scale post-month of the stroke were collected.

Results:

Out of 376 patients, 359 were included, with a mean (standard deviation) age of 67.8 (12.2) years and male predominance (56.2%). Hyperlipidemia and hypertension were the most prevalent comorbidities (91.1% and 80.5%, respectively). The NIHSS, BI and mRS scores were worse among women, with no significant effects for comorbidities. The NIHSS scores at admission and discharge were significantly correlated with the post-month BI and mRS scores.

Conclusion:

The study findings suggest a complex interplay of gender, strict control and prevention of the modifiable stroke risk factors, as well as the association of neurological deficits' intensity with the functional outcomes.

This study aimed to explore the demographics, the clinical risk factors and the scores of the National Institutes of Health Stroke Scale (NIHSS), modified Rankin Scale (mRS) and Barthel Index (BI) scale at different points of time among the survivors of acute ischemic stroke at a tertiary hospital in Jordan. Also, the study aimed to investigate the differences in the scales' scores by the patients' characteristics and the correlations between these scales. Out of 376 screened patients, 359 were included. Their mean (standard deviation) age was 67.8 (12.2) years, and 56.2% were men. Compared with male participants, women scored significantly worse on the NIHSS at admission (7.61 [5.51] vs 9.47 [6.64]; p = 0.048), NIHSS at discharge (5.57 [4.72] vs 7.40 [5.88]; p = 0.028) and BI scale 1 month post-event (78.68 [28.33] vs 66.03 [35.86]; p = 0.011). The mean (standard deviation) mRS score post-month of stroke was lower in men (2.4 [1.7]) than in women (2.9 [1.9]), with a lack of statistical significance (p = 0.097). Thus, despite the male predominance in the cohort, women tended to have a more severe stroke, worse neurological impairment and poorer functional outcomes. Hyperlipidemia had the highest prevalence, sensitivity, positive predictive value and negative predictive value rates, followed by hypertension. No statistically significant differences existed in the comorbidities' NIHSS, BI scale and mRS scores. Strong and significant correlations were observed between the scores of NIHSS at admission and discharge and the BI scale and mRS scores at 1 month post-event. Thus, the authors concluded that neurological deficit severity has a potential role in predicting functioning outcomes and vice versa.

Role of diabetes in stroke: Recent advances in pathophysiology and clinical management

The increasing prevalence of diabetes and stroke is a major global public health concern. Specifically, acute stroke patients, with pre-existing diabetes, pose a clinical challenge. It is established that diabetes is associated with a worse prognosis after acute stroke and the various biological factors that mediate poor recovery profiles in diabetic patients is unknown. The level of association and impact of diabetes, in the setting of reperfusion therapy, is yet to be determined. This article presents a comprehensive overview of the current knowledge of the role of diabetes in stroke, therapeutic strategies for primary and secondary prevention of cardiovascular disease and/or stroke in diabetes, and various therapeutic considerations that may apply during pre-stroke, acute, sub-acute and post-stroke stages. The early diagnosis of diabetes as a comorbidity for stroke, as well as tailored post-stroke management of diabetes, is pivotal to our efforts to limit the burden. Increasing awareness and involvement of neurologists in the management of diabetes and other cardiovascular risk factors is desirable towards improving stroke prevention and efficacy of reperfusion therapy in acute stroke patients with diabetes.

sTWEAK is a leukoaraiosis biomarker associated with neurovascular angiopathy

Objective

Leukoaraiosis (LA) refers to white matter lesions of undetermined etiology associated with the appearance and worsening of vascular pathologies. The aim is to confirm an increased frequency and intensity of LA in symptomatic patients with neurovascular pathology compared with asymptomatic subjects, and its association with circulating serum levels of soluble tumor necrosis factor‐like weak inducer of apoptosis (sTWEAK).

Methods

An observational study was conducted in which two groups of patients were compared. Group I (N = 242) comprised of asymptomatic subjects with arterial hypertension and/or diabetes or with a history of transient ischemic attacks, and Group II (N = 382) comprised patients with lacunar stroke or deep hemispheric intracerebral hemorrhage (ICH) of hypertensive origin. Serum levels of sTWEAK were analyzed and correlated with prevalence and intensity of LA according to the Fazekas scale.

Results

The prevalence of LA was higher in symptomatic (85.1%) versus asymptomatic patients (62.0%). Logistic regression model showed a significant relation of LA with neurovascular pathologies (OR: 2.69, IC 95%: 1.10–6.59, p = 0.003). When stratified according to the Fazekas scale, LA of grade II (OR: 3.53, IC 95%: 1.10–6.59, p = 0.003) and specially grade III (OR: 4.66, 95% CI: 1.09–19.84, p = 0.037) showed correlation with neurovascular pathologies. Increased sTWEAK levels were found in the symptomatic group in all LA grades (p < 0.0001), and associated with 5.06 times more risk of presenting clinical symptoms (OR: 5.06, 95% CI: 2.66–9.75, p < 0.0001).

Interpretation

LA showed a higher prevalence in patients with symptomatic lacunar stroke or deep hemispheric ICH. There is an association between sTWEAK levels and LA degree.

The ENIGMA Stroke Recovery Working Group: Big data neuroimaging to study brain-behavior relationships after stroke

The goal of the Enhancing Neuroimaging Genetics through Meta-Analysis (ENIGMA) Stroke Recovery working group is to understand brain and behavior relationships using well-powered meta- and mega-analytic approaches. ENIGMA Stroke Recovery has data from over 2,100 stroke patients collected across 39 research studies and 10 countries around the world, comprising the largest multisite retrospective stroke data collaboration to date. This article outlines the efforts taken by the ENIGMA Stroke Recovery working group to develop neuroinformatics protocols and methods to manage multisite stroke brain magnetic resonance imaging, behavioral and demographics data. Specifically, the processes for scalable data intake and preprocessing, multisite data harmonization, and large-scale stroke lesion analysis are described, and challenges unique to this type of big data collaboration in stroke research are discussed. Finally, future directions and limitations, as well as recommendations for improved data harmonization through prospective data collection and data management, are provided.

Global white matter structural integrity mediates the effect of age on ischemic stroke outcomes

BACKGROUND

The relationship of global white matter microstructural integrity and ischemic stroke outcomes is not well understood.

AIMS

To investigate the relationship of global white matter microstructural integrity with clinical variables and functional outcomes after acute ischemic stroke.

METHODS

A retrospective analysis of neuroimaging data from 300 acute ischemic stroke patients with magnetic resonance imaging brain obtained within 48 hours of stroke onset and long-term functional outcomes (modified Rankin, mRS) was performed. Peak width of skeletonized mean diffusivity (PSMD), as a measure of global white matter microstructural injury, was calculated in the hemisphere contralateral to the acute infarct. Multivariable linear and logistic regression analyses were performed to identify variables associated with PSMD and excellent functional outcome (mRS < 2) at 90 days, respectively. Mediation analysis was then pursued to characterize how PSMD mediates the effect of age on acute ischemic stroke functional outcomes.

RESULTS

White matter hyperintensity volume, age, pre-stroke disability, and normal-appearing white matter mean diffusivity were independently associated with increased PSMD. In logistic regression analysis, increased infarct volume and PSMD were independent predictors of excellent functional outcome. Additionally, the effect of age on functional outcomes was indirectly mediated by PSMD (P < 0.001).

CONCLUSIONS

As a marker of global white matter microstructural injury, increased PSMD mediates the effect of increased age to contribute to poor acute ischemic stroke functional outcomes. PSMD could serve as a putative radiographic marker of brain age for stroke outcomes prognostication.

Acute Recanalization of Large Vessel Occlusion in the Anterior Circulation Stroke: Is Mechanical Thrombectomy Alone Better in Patients over 80 Years of Age? Findings from a Retrospective Observational Study

Real-world data report worse 3-month clinical outcomes in elderly patients with acute ischemic stroke (AIS) treated with mechanical thrombectomy (MT). The aim was to identify factors influencing clinical outcome in elderly patients with anterior circulation AIS treated with MT (±intravenous thrombolysis (IVT)). In a retrospective, monocentric study, analysis of prospectively collected data of 138 patients (≥80 years) was performed. IVT was an independent negative predictor (OR 0.356; 95% CI: 0.134–0.942) and female sex an independent positive predictor (OR 4.179, 95% CI: 1.300–13.438) of 3-month good clinical outcome (modified Rankin scale 0–2). Female sex was also an independent negative predictor of 3-month mortality (OR 0.244, 95% CI: 0.100–0.599). Other independent negative predictors of 3-month good clinical outcome were older age, lower pre-stroke self-sufficiency, more severe neurological deficit and longer procedural intervals. Mortality was also independently predicted by longer procedural interval and by the occurrence of symptomatic intracerebral hemorrhage (p < 0.05 in all cases). Our results demonstrated, that in patients aged ≥80 years with anterior circulation AIS undergoing MT (±IVT), IVT reduced the chance of 3-month good clinical outcome and female sex was associated with a greater likelihood of 3-month good clinical outcome and lower probability of 3-month mortality.

Carotid Atheroinflammation Is Associated With Cerebral Small Vessel Disease Severity

Background: Atherosclerosis is a systemic inflammatory disease, with common inflammatory processes implicated in both atheroma vulnerability and blood-brain barrier disruption. This prospective multimodal imaging study aimed to measure directly the association between systemic atheroma inflammation (“atheroinflammation”) and downstream chronic cerebral small vessel disease severity.

Methods: Twenty-six individuals with ischemic stroke with ipsilateral carotid artery stenosis of >50% underwent ¹⁸fluoride-fluorodeoxyglucose-positron emission tomography within 2 weeks of stroke. Small vessel disease severity and white matter hyperintensity volume were assessed using 3-tesla magnetic resonance imaging also within 2 weeks of stroke.

Results: Fluorodeoxyglucose uptake was independently associated with more severe small vessel disease (odds ratio 6.18, 95% confidence interval 2.1–18.2, P < 0.01 for the non-culprit carotid artery) and larger white matter hyperintensity volumes (coefficient = 14.33 mL, P < 0.01 for the non-culprit carotid artery).

Conclusion: These proof-of-concept results have important implications for our understanding of the neurovascular interface and potential therapeutic exploitation in the management of systemic atherosclerosis, particularly non-stenotic disease previously considered asymptomatic, in order to reduce the burden of chronic cerebrovascular disease.

Vascular health and diffusion properties of normal appearing white matter in midlife

In this study, we perform a region of interest diffusion tensor imaging and advanced diffusion complexity analysis of normal appearing white matter to determine the impact of vascular health on these diffusivity metrics in midlife adults. 77 participants (26 black, 35 female) at year 30 visit in the Coronary Artery Risk Development in Young Adults longitudinal study were scanned with an advanced diffusion-weighted imaging and fluid-attenuated inversion recovery protocol. Fractional anisotropy and non-linear diffusion complexity measures were estimated. Cumulative measures across 30 years (9 study visits) of systolic blood pressure, body mass index, glucose, smoking and cholesterol were calculated as the area under the curve from baseline up to year 30 examination. Partial correlation analyses assessed the association between cumulative vascular health measures and normal appearing white matter diffusion metrics in these participants. Midlife normal appearing white matter diffusion properties were significantly associated (P < 0.05) with cumulative exposure to vascular risk factors from young adulthood over the 30-year time period. Higher cumulative systolic blood pressure exposure was associated with increased complexity and decreased fractional anisotropy. Higher cumulative body mass index exposure was associated with decreased fractional anisotropy. Additionally, in the normal appearing white matter of black participants (P < 0.05), who exhibited a higher cumulative vascular risk exposure, fractional anisotropy was lower and complexity was higher in comparison to normal appearing white matter in white participants. Higher burden of vascular risk factor exposure from young adulthood to midlife is associated with changes in the diffusion properties of normal appearing white matter in midlife. These changes which may reflect axonal disruption, increased inflammation and/or increased glial proliferation, were primarily observed in both anterior and posterior normal appearing white matter regions of the corpus callosum. These results suggest that microstructural changes in normal appearing white matter are sensitive to vascular health during young adulthood and are possibly therapeutic targets in interventions focused on preserving white matter health across life.

Gut-Derived Metabolite Phenylacetylglutamine and White Matter Hyperintensities in Patients With Acute Ischemic Stroke

Background: White matter hyperintensity (WMH) burden is associated with a higher risk of ischemic stroke. Phenylacetylglutamine (PAGln) is a gut microbiota-derived metabolite that may induce cardiovascular events by activating platelets and increasing the risk of thrombosis. The relationship between plasma PAGln and WMH burden in patients with ischemic stroke is unknown. This study was designed to investigate the association between plasma PAGln and WMH burden in patients with acute ischemic stroke.

Methods: A total of 595 patients with acute ischemic stroke were enrolled in this study within 14 days of symptom onset. The burden of WMH was evaluated using the Fazekas scale based on the fluid-attenuated inversion recovery sequence. The severity of overall WMH was defined as none–mild WMH (total Fazekas score 0–2) or moderate–severe WMH (total Fazekas score 3–6). Based on the severity of periventricular WMH (P-WMH) and deep WMH (D-WMH), patients were categorized into either a none–mild (Fazekas score 0–1) group or a moderate–severe (Fazekas score 2–3) group. Plasma PAGln levels were quantified using liquid chromatography–mass spectrometry.

Results: We found that patients with moderate–severe overall WMH showed higher plasma PAGln levels than patients with none–mild overall WMH, and similar results were found in the analyses according to P-WMH and D-WMH. The logistic regression analysis showed that the fourth PAGln quartile was independently associated with moderate–severe overall WMH (adjusted 95% CI 1.134–4.018) and P-WMH (adjusted 95% CI 1.174–4.226).

Conclusion: These findings suggest that higher plasma PAGln levels are associated with moderate–severe overall WMH and P-WMH in patients with acute ischemic stroke.

MRI Radiomic Signature of White Matter Hyperintensities Is Associated With Clinical Phenotypes

OBJECTIVE

Neuroimaging measurements of brain structural integrity are thought to be surrogates for brain health, but precise assessments require dedicated advanced image acquisitions. By means of quantitatively describing conventional images, radiomic analyses hold potential for evaluating brain health. We sought to: (1) evaluate radiomics to assess brain structural integrity by predicting white matter hyperintensities burdens (WMH) and (2) uncover associations between predictive radiomic features and clinical phenotypes.

METHODS

We analyzed a multi-site cohort of 4,163 acute ischemic strokes (AIS) patients with T2-FLAIR MR images with total brain and WMH segmentations. Radiomic features were extracted from normal-appearing brain tissue (brain mask-WMH mask). Radiomics-based prediction of personalized WMH burden was done using ElasticNet linear regression. We built a radiomic signature of WMH with stable selected features predictive of WMH burden and then related this signature to clinical variables using canonical correlation analysis (CCA).

RESULTS

Radiomic features were predictive of WMH burden (R 2 = 0.855 ± 0.011). Seven pairs of canonical variates (CV) significantly correlated the radiomics signature of WMH and clinical traits with respective canonical correlations of 0.81, 0.65, 0.42, 0.24, 0.20, 0.15, and 0.15 (FDR-corrected p-values CV 1 - 6 < 0.001, p-value CV 7 = 0.012). The clinical CV1 was mainly influenced by age, CV2 by sex, CV3 by history of smoking and diabetes, CV4 by hypertension, CV5 by atrial fibrillation (AF) and diabetes, CV6 by coronary artery disease (CAD), and CV7 by CAD and diabetes.

CONCLUSION

Radiomics extracted from T2-FLAIR images of AIS patients capture microstructural damage of the cerebral parenchyma and correlate with clinical phenotypes, suggesting different radiographical textural abnormalities per cardiovascular risk profile. Further research could evaluate radiomics to predict the progression of WMH and for the follow-up of stroke patients' brain health.

The association between telomere length and ischemic stroke risk and phenotype

The chronological age of a person is a key determinant of etiology and prognosis in the setting of ischemic stroke. Telomere length, an indicator of biological aging, progressively shortens with every cell cycle. Herein, we determined telomere length from peripheral blood leukocytes by Southern blot analyses in a prospective cohort of ischemic stroke patients (n = 163) and equal number of non-stroke controls and evaluated its association with various ischemic stroke features including etiology, severity, and outcome. A shorter telomere length (i.e. lowest quartile; ≤ 5.5 kb) was significantly associated with ischemic stroke (OR 2.95, 95% CI 1.70–5.13). This significant relationship persisted for all stroke etiologies, except for other rare causes of stroke. No significant association was present between admission lesion volume and telomere length; however, patients with shorter telomeres had higher admission National Institutes of Health Stroke Scale scores when adjusted for chronological age, risk factors, etiology, and infarct volume (p = 0.046). On the other hand, chronological age, but not telomere length, was associated with unfavorable outcome (modified Rankin scale > 2) and mortality at 90 days follow-up. The association between shorter telomere length and more severe clinical phenotype at the time of admission, might reflect reduced resilience of cerebral tissue to ischemia as part of biological aging.

Brain Atlas Guided Attention U-Net for White Matter Hyperintensity Segmentation

White Matter Hyperintensities (WMH) are the most common manifestation of cerebral small vessel disease (cSVD) on the brain MRI. Accurate WMH segmentation algorithms are important to determine cSVD burden and its clinical con-sequences. Most of existing WMH segmentation algorithms require both fluid attenuated inversion recovery (FLAIR) images and T1-weighted images as inputs. However, T1-weighted images are typically not part of standard clinical scans which are acquired for patients with acute stroke. In this paper, we propose a novel brain atlas guided attention U-Net (BAGAU-Net) that leverages only FLAIR images with a spatially-registered white matter (WM) brain atlas to yield competitive WMH segmentation performance. Specifically, we designed a dual-path segmentation model with two novel connecting mechanisms, namely multi-input attention module (MAM) and attention fusion module (AFM) to fuse the information from two paths for accurate results. Experiments on two publicly available datasets show the effectiveness of the proposed BAGAU-Net. With only FLAIR images and WM brain atlas, BAGAU-Net outperforms the state-of-the-art method with T1-weighted images, paving the way for effective development of WMH segmentation. Availability: https://github.com/Ericzhang1/BAGAU-Net.

Severe Cerebral Small Vessel Disease Burden Is Associated With Poor Outcomes After Endovascular Thrombectomy in Acute Ischemic Stroke With Large Vessel Occlusion

Background

Despite recent advancements in the treatment of acute ischemic stroke (AIS) with large vessel occlusion (LVO), infarct progression over time and functional outcomes remain variable. This variation in outcomes may be partially attributed to an underlying state of chronic cerebral hypoperfusion and ischemia affecting small cerebral perforating arterioles, venules, and capillaries of the brain; broadly termed cerebral small vessel disease (CSVD). We investigated the association between CSVD burden and the degree of disability following successful recanalization with endovascular thrombectomy (EVT) in patients with AIS presenting with LVO.

Methodology

We conducted a single center retrospective analysis of all patients presenting with AIS LVO between May 2016 and May 2019. Patients who were premorbidly independent and presented within six hours from the last known well (LKW) with a proximal anterior circulation occlusion confirmed on computed tomography (CT) angiography of the head or neck were treated with EVT. Patients presenting after six hours and up to 24 hours from LKW with a target ischemic core to perfusion mismatch profile on CT or magnetic resonance (MR) perfusion, or a clinical imaging mismatch on MR diffusion-weighted imaging, were also treated. Patients with successful revascularization, defined as a thrombolysis in cerebral infarction score 2b or 3, were included and evaluated for CSVD burden. The presence of CSVD was quantified using the Fazekas scale (0-3). All patients were further evaluated for disability at 90 days using the modified Rankin Scale (mRS, range 0-6). An mRS score of ≤2 was defined as a good functional outcome.

Results

Of the 190 patients evaluated, absent (Fazekas grade 0), mild (Fazekas grade 1), moderate (Fazekas grade 2), and severe (Fazekas grade 3) CSVD was present in 33 (17.4%), 84 (44.2%), 35 (18.4%), and 38 (20.0%) patients, respectively. Patients with severe CSVD (Fazekas grade 3) were found to be older, had a higher presenting National Institute of Health Stroke Scale (NIHSS), and had greater proportions of preexisting atrial fibrillation and dementia compared to patients with no CSVD (Fazekas grade 0). Using a multivariate ordinal logistic regression model to adjust for age, presenting NIHSS, thrombus location, LKW to groin puncture time, use of tissue plasminogen activator, ischemic infarct volume, development of a symptomatic intracerebral hemorrhage, and treatment with hemicraniectomy, patients with Fazekas grade 3 were significantly more likely to have poor 90-day functional outcomes compared to patients with Fazekas grade 0 (odds ratio 10.25, 95% confidence interval [3.3-31.84]).

Conclusions

Based on our analytical cohort of AIS LVO patients treated with EVT, we found that patients with severe CSVD burden had worse functional outcomes at 90 days and increased mortality. These results provide evidence that the burden of CSVD may be considered an independent risk factor of poor clinical outcome and a predictor of mortality in patients with AIS presenting with LVO, despite successful radiographic recanalization with EVT.

CNS and peripheral immunity in cerebral ischemia: partition and interaction

Stroke elicits excessive immune activation in the injured brain tissue. This well-recognized neural inflammation in the brain is not just an intrinsic organ response but also a result of additional intricate interactions between infiltrating peripheral immune cells and the resident immune cells in the affected areas. Given that there is a finite number of immune cells in the organism at the time of stroke, the partitioned immune systems of the central nervous system (CNS) and periphery must appropriately distribute the limited pool of immune cells between the two domains, mounting a necessary post-stroke inflammatory response by supplying a sufficient number of immune cells into the brain while maintaining peripheral immunity. Stroke pathophysiology has mainly been neurocentric in focus, but understanding the distinct roles of the CNS and peripheral immunity in their concerted action against ischemic insults is crucial. This review will discuss stroke-induced influences of the peripheral immune system on CNS injury/repair and of neural inflammation on peripheral immunity, and how comorbidity influences each.

National Trends in Utilization and Outcome of Endovascular Thrombectomy for Acute Ischemic Stroke in Elderly

OBJECTIVE

Octogenarians were excluded and/or underrepresented in the major endovascular thrombectomy (EVT) randomized controlled trials, but continue to make up a growing proportion of stroke patients. To evaluate real-world trends in utilization and outcome of EVT in patients ≥80 years in a large nationally representative database.

METHODS

Using the Nationwide Inpatient Sample (2014-2016), we identified patients admitted to United States hospitals with acute ischemic stroke (AIS) who also underwent EVT. The primary endpoint was good outcome (discharge to home/acute rehabilitation center). Poor outcome (discharge to skilled nursing facility or hospice and in-hospital mortality), intracerebral hemorrhage and in-hospital mortality were secondary outcome measures.

RESULTS

In 376,956 patients with AIS, 6,230(1.54%) underwent EVT. 1,547(24.83%) were ≥80. The rate of EVT in AIS patients ≥80 more than doubled from 0.83%(n = 317) in 2014 to 1.83%(n = 695) in 2016. The rate of good outcome in patients ≥80 was 9%, significantly lower than younger patients (26%, p<0.001). In-hospital mortality was 19% in patients ≥80 compared to 13% in the younger cohort (p < 0.001). There was no difference in the rate of hemorrhagic transformation between octogenarians and younger patients (18.52% vs 17.01%, p=0.19). In patients ≥80 years of age, decreasing baseline comorbidity burden independently predicted good outcome (OR 0.258, 95% CI [0.674- 0.935]).

CONCLUSIONS

A two-fold increase in the utilization of EVT in patients ≥80 years of age was seen from 2014 to 2016. While the comparative rate of good outcome is significantly lower in this age group, elderly patients with fewer comorbidities demonstrated better outcomes after EVT.

White Matter Hyperintensity Burden Is Associated With Hippocampal Subfield Volume in Stroke

White matter hyperintensities of presumed vascular origin (WMH) are a prevalent form of cerebral small-vessel disease and an important risk factor for post-stroke cognitive dysfunction. Despite this prevalence, it is not well understood how WMH contributes to post-stroke cognitive dysfunction. Preliminary findings suggest that increasing WMH volume is associated with total hippocampal volume in chronic stroke patients. The hippocampus, however, is a complex structure with distinct subfields that have varying roles in the function of the hippocampal circuitry and unique anatomical projections to different brain regions. For these reasons, an investigation into the relationship between WMH and hippocampal subfield volume may further delineate how WMH predispose to post-stroke cognitive dysfunction. In a prospective study of acute ischemic stroke patients with moderate/severe WMH burden, we assessed the relationship between quantitative WMH burden and hippocampal subfield volumes. Patients underwent a 3T MRI brain within 2–5 days of stroke onset. Total WMH volume was calculated in a semi-automated manner. Mean cortical thickness and hippocampal volumes were measured in the contralesional hemisphere. Total and subfield hippocampal volumes were measured using an automated, high-resolution, ex vivo computational atlas. Linear regression analyses were performed for predictors of total and subfield hippocampal volumes. Forty patients with acute ischemic stroke and moderate/severe white matter hyperintensity burden were included in this analysis. Median WMH volume was 9.0 cm³. Adjusting for intracranial volume and stroke laterality, age (β = −3.7, P < 0.001), hypertension (β = −44.7, P = 0.04), WMH volume (β = −0.89, P = 0.049), and mean cortical thickness (β = 286.2, P = 0.006) were associated with total hippocampal volume. In multivariable analysis, age (β = −3.3, P < 0.001) and cortical thickness (β = 205.2, P = 0.028) remained independently associated with total hippocampal volume. In linear regression for predictors of hippocampal subfield volume, increasing WMH volume was associated with decreased hippocampal-amygdala transition area volume (β = −0.04, P = 0.001). These finding suggest that in ischemic stroke patients, increased WMH burden is associated with selective hippocampal subfield degeneration in the hippocampal-amygdala transition area.

White Matter Hyperintensities Predict Response to Language Treatment in Poststroke Aphasia

BACKGROUND

White matter hyperintensities (WMH) are a radiological marker of brain health that has been associated with language status in poststroke aphasia; however, its association with language treatment outcomes remains unknown.

OBJECTIVE

To determine whether WMH in the right hemisphere (RH) predict response to language therapy independently from demographics and stroke lesion-related factors in poststroke aphasia.

METHODS

We used the Fazekas scale to rate WMH in the RH in 30 patients with poststroke aphasia who received language treatment. We developed ordinal regression models to examine language treatment effects as a function of WMH severity after controlling for aphasia severity, stroke lesion volume, time post onset, age, and education level. We also evaluated associations between WMH severity and both pre-treatment naming ability and executive function.

RESULTS

The severity of WMH in the RH predicted treatment response independently from demographic and stroke-related factors such that patients with less severe WMH exhibited better treatment outcome. WMH scores were not significantly correlated with pretreatment language scores, but they were significantly correlated with pretreatment scores of executive function.

CONCLUSION

We suggest that the severity of WMH in the RH is a clinically relevant predictor of treatment response in this population.

Long-range fibre damage in small vessel brain disease affects aphasia severity

We sought to determine the underlying pathophysiology relating white matter hyperintensities to chronic aphasia severity. We hypothesized that: (i) white matter hyperintensities are associated with damage to fibres of any length, but to a higher percentage of long-range compared to mid- and short-range intracerebral white matter fibres; and (ii) the number of long-range fibres mediates the relationship between white matter hyperintensities and chronic post-stroke aphasia severity. We measured the severity of periventricular and deep white matter hyperintensities and calculated the number and percentages of short-, mid- and long-range white matter fibres in 48 individuals with chronic post-stroke aphasia. Correlation and mediation analyses were performed to assess the relationship between white matter hyperintensities, connectome fibre-length measures and aphasia severity as measured with the aphasia quotient of the Western Aphasia Battery-Revised (WAB-AQ). We found that more severe periventricular and deep white matter hyperintensities correlated with a lower proportion of long-range fibres (r = -0.423, P = 0.003 and r = -0.315, P = 0.029, respectively), counterbalanced by a higher proportion of short-range fibres (r = 0.427, P = 0.002 and r = 0.285, P = 0.050, respectively). More severe periventricular white matter hyperintensities also correlated with a lower proportion of mid-range fibres (r = -0.334, P = 0.020), while deep white matter hyperintensities did not correlate with mid-range fibres (r = -0.169, P = 0.250). Mediation analyses revealed: (i) a significant total effect of periventricular white matter hyperintensities on WAB-AQ (standardized beta = -0.348, P = 0.008); (ii) a non-significant direct effect of periventricular white matter hyperintensities on WAB-AQ (P > 0.05); (iii) significant indirect effects of more severe periventricular white matter hyperintensities on worse aphasia severity mediated in parallel by fewer long-range fibres (effect = -6.23, bootstrapping: standard error = 2.64, 95%CI: -11.82 to -1.56) and more short-range fibres (effect = 4.50, bootstrapping: standard error = 2.59, 95%CI: 0.16 to 10.29). We conclude that small vessel brain disease seems to affect chronic aphasia severity through a change of the proportions of long- and short-range fibres. This observation provides insight into the pathophysiology of small vessel brain disease, and its relationship with brain health and chronic aphasia severity.

Cerebral small vessel disease or intracranial large vessel atherosclerosis may carry different risk for future strokes

Background

The effect of cerebral small vessel disease (CSVD) and intracranial arterial stenosis (ICAS) on stroke outcomes remains unclear.

Methods

Data of 1045 patients with minor stroke or transient ischaemic attack (TIA) were obtained from 45 sites of the Clopidogrel in High-Risk Patients with Acute Non-disabling Cerebrovascular Events (CHANCE) trial. We assessed the associations of burdens of CSVD and ICAS with new strokes and bleeding events using multivariate Cox regression models and those with modified Rankin Scale (mRS) scores using ordinal logistic regression models.

Results

Among the 1045 patients, CSVD was present in 830 cases (79.4%) and ICAS in 460 (44.0%). Patients with >1 ICAS segment showed the highest risk of new strokes (HR 2.03, 95% CI 1.15 to 3.56, p=0.01). No association between CSVD and the occurrence of new strokes was found. The presence of severe CSVD (common OR (cOR) 2.01, 95% CI 1.40 to 2.89, p<0.001) and >1 ICAS segment (cOR 2.15, 95% CI 1.57 to 2.93, p<0.001) was associated with higher mRS scores. Severe CSVD (HR 10.70, 95% CI 1.16 to 99.04, p=0.04), but not ICAS, was associated with a higher risk of bleeding events. Six-point modified CSVD score improved the predictive power for bleeding events and disability.

Interpretation

CSVD is associated with more disability and bleeding events, and ICAS is associated with an increased risk of stroke and disability in patients with minor stroke and TIA at 3 months. CSVD and ICAS may represent different vascular pathologies and play distinct roles in stroke outcomes.

Trial registration number

NCT00979589

Association between white matter hyperintensities and stroke in a West African patient population: Evidence from the Stroke Investigative Research and Educational Network study

BACKGROUND

This study is part of the Stroke Investigative Research and Educational Network (SIREN), the largest study of stroke patients in Africa to date, with computed tomography (CT) or magnetic resonance (MR) imaging data for each patient to confirm stroke. Prior imaging studies performed using high-field MR (≥1.5T) have shown that white matter hyperintensities (WMH), signs of microangiopathy in the subcortical brain, are correlated with many stroke risk factors as well as poor stroke outcomes. The aim of this study was the evaluation of MR images (0.3T-1.5T) from the SIREN study to determine associations between WMH volumes in West African patients and both stroke outcomes and stroke risk factors identified in the SIREN study.

MATERIALS AND METHODS

Brain MR images of 130 Western African stroke patients (age ​= ​57.87 ​± ​14.22) were processed through Lesion Segmentation Toolbox of the Statistical Parametric Mapping software to extract all areas of hyperintensity in the brain. WMH was separated from stroke lesion hyperintensity and WMH volume was computed and summed. A stepwise linear regression and multivariate analysis was performed between patients' WMH volume and sociodemographic and clinical indices.

RESULTS

Multivariate analysis showed that high WMH volume was statistically significantly positively correlated with age (β ​= ​0.44, p ​= ​0.001), waist/hip ratio (β ​= ​0.22, p ​= ​0.03), and platelet count (β ​= ​0.19, p ​= ​0.04) after controlling for head size in a Western African stroke population.

CONCLUSION

Associations between WMH and age and waist/hip ratio previously identified in Western countries were demonstrated for the first time in a resource-limited, homogeneous black African community using low-field MR scanners.

The association of white matter hyperintensities with stroke outcomes and antiplatelet therapy in minor stroke patients

Background

To characterize the severity and distribution of white matter hyperintensities (WMHs) and to assess the relationship of WMHs with initial stroke severity, 3-month functional outcome, stroke recurrence and response to antiplatelet therapies.

Methods

In Clopidogrel High-risk Patients with Acute Nondisabling Cerebrovascular Events (CHANCE) trial, 787 minor stroke patients with baseline magnetic resonance imaging (MRI) information were included in this analysis. Deep and periventricular WMHs (DWMHs and PVWMHs) were rated using the Fazekas scale and categorized into mild (grades 0–2), moderate (grades 3–4) and severe (grades 5–6). Multivariable logistic regression was used to examine the associations between WMHs severities and outcomes, including initial stroke severity by the National Institutes of Health Stroke Scale (NIHSS) scores, 3-month functional outcome by modified Rankin Scale (mRS), and stroke recurrence. Cox proportional hazards model was used to assess the treatment-by-subgroup interaction effect.

Results

Among the 787 patients in this analysis, 432 (54.9%) had moderate or severe WMHs (3-6). Compared with mild WMHs, the adjusted odds ratio (OR) of severe WMHs for risk of higher NIHSS was 2.10, 95% confidence interval (CI), 1.26–3.48 (P=0.004). Both severities of SDWMHs (OR 1.66; 95% CI, 1.15–2.40; P=0.007) and PVWMHs (OR 1.47; 95% CI, 1.02–2.10; P=0.04) were associated with higher NIHSS scores. There were no statistically significant associations of WMHs with 3-month functional outcome and stroke recurrence. There were no significant interactions between WMHs and antiplatelet therapy.

Conclusions

In patients with minor stroke, both SDWMHs and PVWMHs might related with initial stroke severity. No interaction was detected between the severity of WMHs and antiplatelet treatment.

Prospectively Collected Cardiovascular Biomarkers and White Matter Hyperintensity Volume in Ischemic Stroke Patients

BACKGROUND

Few prospective cohort studies collect detailed information on stroke characteristics among individuals who experience ischemic stroke, including white matter hyperintensity volume, and thus cannot explore how prospectively collected biomarkers prior to the stroke influence white matter hyperintensity volume. We explored the association between a large panel of prospectively collected lipid and inflammatory biomarkers and white matter hyperintensity volume among participants in the Women's Health Study with incident ischemic stroke.

METHODS

Among Women's Health Study participants with first ischemic stroke who had baseline serum biomarkers and available magnetic resonance imaging, we measured white matter hyperintensity volume using a validated semi-automated method. Linear regression was used to explore the associations between biomarkers and log-transformed white matter hyperintensity volume.

RESULTS

After multivariate adjustment, a 1% increment in HbA1c% was associated with an increase in white matter hyperintensity volume (P value = .05). Evidence of a nonlinear association between high density lipoprotein cholesterol levels and ApoA1 levels with white matter hyperintensity volume was noted (P values for nonlinearity = .01 and .001, respectively). No other biomarkers were significantly associated with white matter hyperintensity volume.

CONCLUSIONS

Chronic hyperglycemia as evidenced by HbA1c levels measured years prior to stroke is associated with white matter hyperintensity volume at the time of stroke. Additional research is needed to explain why low levels of high density lipoprotein cholesterol levels and ApoA1 may be associated with similar white matter hyperintensity volume as high levels.

Cerebral Small Vessel Diseases and Sleep Related Strokes

BACKGROUND AND PURPOSE

Sleep related Stroke (SRS) is common and has been associated with cerebral small vessel diseases (SVD) in ischemic strokes (ISs). We tested the hypothesis that SRS is associated with SVD in both ischemic and hemorrhagic stroke.

METHODS

Prospectively collected data from patients consecutively enrolled after intracerebral hemorrhage (ICH) related to SVD or after IS were analyzed. Symptom onset was recorded as SRS versus awake. Each ICH was grouped according to lobar and deep locations. The IS cohort was etiologically characterized based on the Causative Classification of Stroke system. Frequencies of SRS within and between ICH and IS cohorts as well as its associations (etiology, risk factors) were analyzed.

RESULTS

We analyzed 1812 IS (mean age 67.9 years ± 15.9 years, 46.4% female) and 1038 ICH patients (mean age 72.5 years ± 13.0 years, 45.4% female). SRS was significantly more common among SVD-related ICH patients (n = 276, 26.6%) when compared to all IS (n = 363, 20.0%, P < .001) and in both, small artery occlusion (SAO) related IS and lobar ICH within the respective IS and ICH cohorts (16.3% SRS versus 9.1% awake for SAO within all IS, P < .001; and 57.1% SRS versus 47.7% awake for lobar bleeds within all ICH, P = .008). These associations remained significant after controlling for age, sex and risk factors.

CONCLUSIONS

SRS was associated with SVD. The SAO etiology and cerebral amyloid angiopathy related lobar ICH suggest that the presence of SVD can interact with sleep or arousal related hemodynamic changes to cause ischemic and hemorrhagic stroke.

Comparative Effectiveness of Endovascular Thrombectomy in Elderly Stroke Patients

Background and Purpose- Strokes in patients aged ≥80 years are common, and advanced age is associated with relatively poor poststroke functional outcome. The current guidelines do not recommend an upper age limit for endovascular thrombectomy (EVT). The purpose of this study is to evaluate the effectiveness of EVT in acute stroke because of large vessel occlusion for elderly patients >age 80 years. Methods- A Markov decision analytic model was constructed from a societal perspective to evaluate health outcomes in terms of quality-adjusted life years (QALYs) after EVT for acute ischemic stroke because of large vessel occlusion in patients above age 80 years. Age-specific input parameters were obtained from the most recent/comprehensive literature. Good outcome was defined as a modified Rankin Scale score ≤2. Probabilistic, 1-way, and 2-way sensitivity analyses were performed for both healthy patients and patients with disability at baseline. Results- Base case calculation showed in functionally independent patients at baseline, intravenous thrombolysis (IVT) with tPA (tissue-type plasminogen activator) only to be the better strategy with 3.76 QALYs compared to 2.93 QALYs for patients undergoing EVT. The difference in outcome is 0.83 QALY (equivalent to 303 days of life in perfect health). For patients with baseline disability, IVT only yields a utility of 1.92 QALYs and EVT yields a utility of 1.65 QALYs. The difference is 0.27 QALYs (equivalent to 99 days of life in perfect health). Multiple sensitivity analyses showed that the effectiveness of EVT is significantly determined by the morbidity and mortality after both IVT and EVT strategies, respectively. Conclusions- Our study demonstrates the impact of relevant factors on the effectiveness of EVT in patients above 80 years of age. Morbidity and mortality after both IVT and EVT strategies significantly influence the outcomes in both healthy and disabled patients at baseline. Better identification of patients not benefiting from IVT would optimize the selective use of EVT thereby improving its effectiveness.

Normal-appearing white matter microstructural injury is associated with white matter hyperintensity burden in acute ischemic stroke

BACKGROUND

White matter hyperintensity of presumed vascular origin is a risk factor for poor stroke outcomes. In patients with acute ischemic stroke, however, the in vivo mechanisms of white matter microstructural injury are less clear.

AIMS

To characterize the directional diffusivity components in normal-appearing white matter and white matter hyperintensity in acute ischemic stroke patients.

METHODS

A retrospective analysis was performed on a cohort of patients with acute ischemic stroke and brain magnetic resonance imaging with diffusion tensor imaging sequences acquired within 48 h of admission. White matter hyperintensity volume was measured in a semi-automated manner. Median fractional anisotropy, mean diffusivity, radial diffusivity, and axial diffusivity values were calculated within normal-appearing white matter and white matter hyperintensity in the hemisphere contralateral to the acute infarct. Linear regression analysis was performed to evaluate predictors of white matter hyperintensity volume and normal-appearing white matter diffusivity metrics.

RESULTS

In 319 patients, mean age was 64.9 ± 15.9 years. White matter hyperintensity volume was 6.33 cm³ (interquartile range 3.0-12.6 cm³). Axial and radial diffusivity were significantly increased in white matter hyperintensity compared to normal-appearing white matter. In multivariable linear regression, age (β = 0.20, P = 0.003) and normal-appearing white matter axial diffusivity (β = 37.9, P < 0.001) were independently associated with white matter hyperintensity volume. Subsequent analysis demonstrated that increasing age (β = 0.004, P < 0.001) and admission diastolic blood pressure (β = 0.001, P = 0.02) were independent predictors of normal-appearing white matter axial diffusivity in multivariable linear regression.

CONCLUSIONS

Normal-appearing white matter axial diffusivity increases with age and is an independent predictor of white matter hyperintensity volume in acute ischemic stroke.

Deiodinases, organic anion transporter polypeptide polymorphisms and ischemic stroke outcomes

BACKGROUND

Ischemic stroke is a major cause of premature death and chronic disability worldwide, and individual variation in functional outcome is strongly influenced by genetic factors. Neuroendocrine signaling by the hypothalamic-hypophyseal-thyroid axis is a critical regulator of post-stroke pathogenesis, suggesting that allelic variants in thyroid hormone (TH) signaling can influence stroke outcome.

AIM

To examine associations between acute ischemic stroke (AIS) outcome and allelic variants of the TH metabolizing enzymes deiodinase type 1-3 (DIO1-3) and membrane transporting organic anion polypeptide C1 (OATP1C1).

METHODS

Eligible AIS patients from Lithuania (n = 248) were genotyped for ten DIO1-3 and OATP1C1 single nucleotide polymorphisms (SNPs): DIO1 rs12095080-A/G, rs11206244-C/T, and rs2235544-A/C; DIO2 rs225014-T/C and rs225015-G/A; DIO3 rs945006-T/G; OATP1C1 rs974453-G/A, rs10444412-T/C, rs10770704-C/T, and rs1515777-A/G. Functional outcome was evaluated one year after index AIS using the modified Rankin Scale. Analyses were adjusted for important confounders, including serum free triiodothyronine.

RESULTS

After adjustment for potential confounders, the major allelic (wild-type) DIO3 genotype rs945006-TT was associated with better 1-year AIS functional outcome (odds ratio [OR] = 0.25; 95% confidence interval [CI]: 0.08-0.74; p = .013), while the wild-type OATP1C1 genotype rs10770704-CC was associated with poorer outcome (OR = 2.00, 95%CI: 1.04-3.86; p = .038).

CONCLUSION

Allelic variants in thyroid axis genes may prove useful for prognosis and treatment guidance.