Identification and characterization of extrachromosomal circular DNA in large-artery atherosclerotic stroke

Extrachromosomal circular DNA (eccDNA) is a new biomarker and regulator of diseases. However, the role of eccDNAs in large-artery atherosclerotic (LAA) stroke remains unclear. Through high-throughput circle-sequencing technique, the length distribution, genomic characteristic and motifs feature of plasma eccDNA from healthy controls (CON) and patients with LAA stroke were analysed. Then, the potential functions of the annotated eccDNAs were investigated using GO and KEGG pathway analyses. EccDNAs mapped to the reference genome showed SHN3 and BCL6 were LAA stroke unique transcription factors. The genes of differentially expressed eccDNAs between LAA stroke patients and CON were mainly involved in axon/dendrite/neuron projection development and maintenance of cellular structure via Wnt, Rap1 and MAPK pathways. Moreover, LAA stroke unique eccDNA genes played a role in regulation of coagulation and fibrinolysis, and there were five LAA stroke unique eccDNAs (Chr2:12724406-12724784, Chr4:1867120-186272046, Chr4:186271494-186271696, Chr7:116560296-116560685 and Chr11:57611780-5761192). Additionally, POLR2C and AURKA carried by ecDNAs (eccDNA size >100 kb) of LAA stroke patients were significantly associated with development of LAA stroke. Our data firstly revealed the characteristics of eccDNA in LAA stroke and the functions of LAA stroke unique eccDNAs and eccDNA genes, suggesting eccDNA is a novel biomarker and mechanism of LAA stroke.

Burden of intracranial artery calcification in white patients with ischemic stroke

INTRODUCTION

The diagnostic workup of stroke doesn't identify an underlying cause in two-fifths of ischemic strokes. Intracranial arteriosclerosis is acknowledged as a cause of stroke in Asian and Black populations, but is underappreciated as such in whites. We explored the burden of Intracranial Artery Calcification (IAC), a marker of intracranial arteriosclerosis, as a potential cause of stroke among white patients with recent ischemic stroke or TIA.

PATIENTS AND METHODS

Between December 2005 and October 2010, 943 patients (mean age 63.8 (SD ± 14.0) years, 47.9% female) were recruited, of whom 561 had ischemic stroke and 382 a TIA. CT-angiography was conducted according to stroke analysis protocols. The burden of IAC was quantified on these images, whereafter we assessed the presence of IAC per TOAST etiology underlying the stroke and assessed associations between IAC burden, symptom severity, and short-term functional outcome.

RESULTS

IAC was present in 62.4% of patients. Furthermore, IAC was seen in 84.8% of atherosclerotic strokes, and also in the majority of strokes with an undetermined etiology (58.5%). Additionally, patients with larger IAC burden presented with heavier symptoms (adjusted OR 1.56 (95% CI [1.06-2.29]), but there was no difference in short-term functional outcome (1.14 [0.80-1.61]).

CONCLUSION

IAC is seen in the majority of white ischemic stroke patients, aligning with findings from patient studies in other ethnicities. Furthermore, over half of patients with a stroke of undetermined etiology presented with IAC. Assessing IAC burden may help identify the cause in ischemic stroke of undetermined etiology, and could offer important prognostic information.

Effect of collateral status on the outcomes of endovascular treatment of acute basilar artery occlusion due to large-artery atherosclerosis

OBJECTIVE

Authors of this study aimed to evaluate the effects of collateral status on the prognostic value of endovascular treatment (EVT) in patients with basilar artery occlusion (BAO) due to large-artery atherosclerosis (LAA).

METHODS

The study included 312 patients from the BASILAR (Endovascular Treatment for Acute Basilar Artery Occlusion Study) registry who had undergone EVT for acute BAO due to LAA and whose composite collateral scores were available. The effects of collateral status on EVT were assessed based on the composite collateral score (0-2 vs 3-5). The primary outcome was a favorable outcome (modified Rankin Scale score of 0-3) at 90 days.

RESULTS

The composite collateral score was 0-2 in 130 patients and 3-5 in 182. A good collateral status (composite collateral score 3-5) was associated with a favorable outcome (66/182 [36.3%] vs 31/130 [23.8%], adjusted odds ratio [aOR] 2.21, 95% CI 1.18-4.14, p = 0.014). A lower baseline National Institutes of Health Stroke Scale (NIHSS) score was an independent predictor of a favorable outcome in the poor collateral status group (aOR 0.91, 95% CI 0.87-0.96, p = 0.001). In the good collateral status group, there was a significant correlation between favorable outcomes and a younger age (aOR 0.96, 95% CI 0.92-0.99, p = 0.016), lower baseline NIHSS score (aOR 0.89, 95% CI 0.85-0.93, p < 0.001), lower proportion of diabetes mellitus (aOR 0.31, 95% CI 0.13-0.75, p = 0.009), and shorter procedure time (aOR 0.99, 95% CI 0.98-1.00, p = 0.003).

CONCLUSIONS

A good collateral status was a strong prognostic factor after EVT in patients with BAO underlying LAA. A shorter procedure time was associated with favorable outcomes in patients with a good collateral status.

Twenty-four-hour ambulatory blood pressure variability and association with ischemic stroke subtypes in the subacute stage

Background and purpose

Blood pressure (BP) variability (BPV) increases the risk of cerebral disease in both hemorrhagic and ischemic strokes. However, whether BPV is associated with different types of ischemic stroke remains unclear. In this study, we explored the relationship between BPV and ischemic stroke subtypes.

Methods

We enrolled consecutive patients aged 47-95 years with ischemic stroke in the subacute stage. We categorized them into four groups based on their artery atherosclerosis severity, brain magnetic resonance imaging markers, and disease history: large-artery atherosclerosis, branch atheromatous disease, small-vessel disease, and cardioembolic stroke. Twenty-four-hour ambulatory blood pressure monitoring was performed, and the mean systolic blood pressure/diastolic blood pressure, standard deviation, and coefficient of variation were calculated. A multiple logistic regression model and random forest were used to test the relationship between BP and BPV in the different types of ischemic stroke.

Results

A total of 286 patients, including 150 men (73.0 ± 12.3 years) and 136 women (77.8 ± 9.6 years) were included in the study. Of these, 86 (30.1%) patients had large-artery atherosclerosis, 76 (26.6%) had branch atheromatous disease, 82 (28.7%) had small-vessel disease, and 42 (14.7%) had cardioembolic stroke. There were statistically significant differences in BPV between subtypes of ischemic stroke in 24-h ambulatory blood pressure monitoring. The random forest model showed that BP and BPV were important features associated with ischemic stroke. Multinomial logistic regression analysis demonstrated that systolic blood pressure levels; systolic blood pressure variability at 24 h, daytime and nighttime; and nighttime diastolic blood pressure were independent risk factors for large-artery atherosclerosis after adjustment for confounders. When compared to branch atheromatous disease and small-vessel disease, nighttime diastolic blood pressure and standard deviation of diastolic blood pressure were significantly associated with patients in the cardioembolic stroke group. However, a similar statistical difference was not seen in patients with large-artery atherosclerosis.

Conclusion

The results of this study indicate a discrepancy in blood pressure variability among different ischemic stroke subtypes during the subacute stage. Higher systolic blood pressure and systolic blood pressure variability during the 24 h, daytime, and nighttime, and nighttime diastolic blood pressure were independent predictors for large-artery atherosclerosis stroke. Increased nighttime diastolic BPV was an independent risk factor for cardioembolic stroke.

Causative Classification of Ischemic Stroke by the Machine Learning Algorithm Random Forests

Background

Prognosis, recurrence rate, and secondary prevention strategies differ by different etiologies in acute ischemic stroke. However, identifying its cause is challenging.

Objective

This study aimed to develop a model to identify the cause of stroke using machine learning (ML) methods and test its accuracy.

Methods

We retrospectively reviewed the data of patients who had determined etiology defined by the Trial of ORG 10172 in Acute Stroke Treatment (TOAST) from CASE-II (NCT04487340) to train and evaluate six ML models, namely, Random Forests (RF), Logistic Regression (LR), Extreme Gradient Boosting (XGBoost), K-Nearest Neighbor (KNN), Ada Boosting, Gradient Boosting Machine (GBM), for the detection of cardioembolism (CE), large-artery atherosclerosis (LAA), and small-artery occlusion (SAO). Between October 2016 and April 2020, patients were enrolled consecutively for algorithm development (phase one). Between June 2020 and December 2020, patients were enrolled consecutively in a test set for algorithm test (phase two). Area under the curve (AUC), precision, recall, accuracy, and F1 score were calculated for the prediction model.

Results

Finally, a total of 18,209 patients were enrolled in phase one, including 13,590 patients (i.e., 6,089 CE, 4,539 LAA, and 2,962 SAO) in the model, and a total of 3,688 patients were enrolled in phase two, including 3,070 patients (i.e., 1,103 CE, 1,269 LAA, and 698 SAO) in the model. Among the six models, the best models were RF, XGBoost, and GBM, and we chose the RF model as our final model. Based on the test set, the AUC values of the RF model to predict CE, LAA, and SAO were 0.981 (95%CI, 0.978-0.986), 0.919 (95%CI, 0.911-0.928), and 0.918 (95%CI, 0.908-0.927), respectively. The most important items to identify CE, LAA, and SAO were atrial fibrillation and degree of stenosis of intracranial arteries.

Conclusion

The proposed RF model could be a useful diagnostic tool to help neurologists categorize etiologies of stroke.

Clinical Trial Registration

[www.ClinicalTrials.gov], identifier [NCT01274117].

Correlation between Plasma Levels of RIP3 and Acute Ischemic Stroke with Large-Artery Atherosclerosis

BACKGROUND

Receptor-interacting serine-threonine protein kinase 3 (RIP3) was previously discovered to be an important medium in the occurrence and development of major atherosclerotic cerebral infarction. However, the role of RIP3 in acute ischemic stroke remains unclear.

OBJECTIVE

This study aimed to explore the correlation between plasma levels of RIP3 and acute ischemic stroke with large-artery atherosclerosis (LAA).

METHODS

This prospective study enrolled 116 patients with LAA, 40 healthy controls and 30 acute ischemic stroke patients with small-artery occlusion. The patients with LAA were divided according to the quartile of plasma levels of RIP3. Logistic regression model was used for comparison. The ROC curve was performed to evaluate the predictive value.

RESULTS

In patients with LAA, the RIP3 levels in patients with poor outcomes as well as neurological deterioration were significantly higher than those with good outcomes (P < 0.001) and without neurological deterioration (P = 0.014) respectively. Patients in the highest levels of plasma RIP3 quartile were more likely to have neurological deterioration (OR, 11.07; 95% CI, 1.990-61.582) and poor outcomes (OR, 35.970; 95% CI, 5.392-239.980) compared with the lowest. The optimal cut-off value for neurological deterioration was 1127.75 pg/mL (specificity, 66.7%; sensitivity, 69.2%), that for poor prognosis was 1181.82 pg/mL (specificity, 89.7%; sensitivity, 62.1%).

CONCLUSION

Elevated levels of plasma RIP3 were significantly associated with neurological deterioration and poor prognosis in patients with LAA. Significant increase in plasma RIP3 levels can predict neurological deterioration and poor prognosis of these patients.

Increased Platelet-to-Lymphocyte Ratio is an Independent Predictor of Hemorrhagic Transformation and In-Hospital Mortality Among Acute Ischemic Stroke with Large-Artery Atherosclerosis Patients

Background

The platelet-to-lymphocyte ratio (PLR) is an inflammation marker of acute ischemic stroke, but its significance in patients with hemorrhage transformation (HT) after acute ischemic stroke with large-artery atherosclerosis (AIS-LAA) is unclear, and we also identified the relationship between PLR and in-hospital mortality of HT after AIS-LAA.

Methods

This was a retrospective analysis of patients with AIS-LAA. The PLR was calculated according to platelet and lymphocyte counts on admission. HT was defined on follow-up magnetic resonance imaging or computed tomography when neurologic deterioration worsened during hospitalization. The univariate analysis and multivariate logistic regression were performed to assess the association of PLR, HT and in-hospital mortality of HT after AIS-LAA.

Results

We included 328 Chinese AIS-LAA patients (mean age 67.2±11.1 years; 70.4% male). HT occurred in 38 patients (11.6%). After multivariate regression analyses, NRL (odds ratio [OR] 1.354, 95% confidence interval [CI] 1.176–1.559, P<0.001) and PLR (odds ratio [OR] 3.869, 95% confidence interval [CI] 2.233–5.702, P<0.001) were independently associated with HT after AIS-LAA. The area under the ROC curve (AUC) value of PLR (0.72, 95% CI (0.64–0.80), P<0.001) tested a greater discriminatory ability compared with neutrophil-lymphocyte ratio (NLR) (0.67, 95% CI (0.58–0.76), P<0.001). Meanwhile, PLR was found to be significantly related to HT after AIS-LAA, including in subtypes of artery-to-artery embolization (aOR 1.699, 95% CI 1.298–3.215, P<0.001), in-situ thrombosis (aOR4.499, 95% CI 1.344–9.054, P<0.001) and branch atheromatous disease (aOR3.239, 95% CI 1.098–8.354, P<0.001). Increased PLR predicts high in-hospital mortality of HT after AIS-LAA (OR 1.041, 95% CI (1.006–1.077), P=0.020; aOR 1.053, 95% CI (1.004–1.104), P=0.034).

Conclusion

High PLR is associated with greater risk of HT in AIS-LAA patients, including in artery-to-artery embolization, in-situ thrombosis and branch atheromatous disease. Meanwhile, increased PLR predicts high in-hospital mortality of HT after AIS-LAA.

Differential value of intima thickness in ischaemic stroke due to large-artery atherosclerosis and small-vessel occlusion

No study has examined the differential value of arterial intima thickness in the subtypes of acute ischaemic stroke. This study aimed to assess whether intima thickness of carotid artery (CIT), radial artery (RIT) and dorsalis pedis artery (PIT) have an independent and additive value in differentiating ischaemic stroke subtypes due to large‐artery atherosclerosis (LAA) or small‐vessel occlusion (SVO). One hundred and sixty‐one patients with LAA and 79 patients with SVO were recruited. CIT, RIT and PIT were measured with a 24‐MHz ultrasound transducer. Binary logistic regression analysis was used to evaluate the differential values of the different parameters in the two subtypes. ROC curve analyses were plotted to compare the differential performance of different parameters and the combination model. Both RIT and PIT were substantially thicker in LAA than in SVO stroke patients. RIT and carotid intima‐media thickness had similar performances in differentiating stroke subtypes. Introduction of RIT to traditional atherosclerotic associated risk factors had a marginal satisfactory differential performance for LAA and SVO stroke patients (AUC 0.775). RIT is a promising parameter for LAA and SVO subgroup classification. The combination of RIT and traditional risk factors might be a promising tool for differentiating ischaemic stroke subgroups.

Increased systemic immune-inflammation index predicts hemorrhagic transformation in anterior circulation acute ischemic stroke due to large-artery atherosclerotic

BACKGROUND AND PURPOSE

Inflammation and immune response play an important role in hemorrhage transformation after acute ischemic stroke. According to previous studies, systemic immune-inflammation index is associated with severity of stroke. We aimed to evaluate the association between systemic immune-inflammation index and hemorrhage transformation in anterior circulation acute ischemic stroke due to large-artery atherosclerosis.

METHODS

This was a retrospective analysis of patients with anterior circulation acute ischemic stroke due to large-artery atherosclerosis. The laboratory data were collected within 24 h after admission. Hemorrhage transformation was defined on follow-up magnetic resonance imaging or Computed Tomography. The univariate analysis and multivariate logistic regression were performed to assess the association of systemic immune-inflammation index with hemorrhage transformation. Then the relationship between systemic immune-inflammation index and hemorrhage transformation in different stroke subtypes was further studied.

RESULTS

We included 310 Chinese anterior circulation acute ischemic stroke patients due to large-artery atherosclerosis (mean age 65 ± 11.4 years; 72.6% male). Hemorrhage transformation occurred in 41 patients (13.2%). After multivariate regression analyses, systemic immune-inflammation index (odds ratio [OR] 1.109, 95% Confidence Interval [CI] 1.054-1.167, p＜0.001) was independently associated with hemorrhage transformation. Systemic immune-inflammation index was found to be significantly related to hemorrhagic transformation in artery-to-artery embolization (OR 1.111, 95% CI 1.029-1.210, p＜0.001) and in-situ thrombosis (OR 1.059, 95% CI 1.011-1.194, p = 0.045).

CONCLUSIONS

Higher systemic immune-inflammation index is associated with greater risk of hemorrhagic transformation in patients with anterior circulation acute ischemic stroke due to large-artery atherosclerosis, especially in artery-to-artery embolization and in-situ thrombosis.

Outcomes of Ischemic Stroke and Associated Factors Among Elderly Patients With Large-Artery Atherosclerosis: A Hospital-Based Follow-Up Study in China

Large-artery atherosclerotic (LAA) stroke is the most common subtype of ischemic stroke. However, risk factors for long-term outcomes of LAA stroke in the elderly Chinese population have not been well-described. Therefore, we aimed to assess outcomes and risk factors at 3, 12, and 36 months after LAA stroke onset among stroke patients aged 60 years and older. All consecutive LAA patients aged ≥ 60 years were prospectively recruited from Dongying People's Hospital between January 2016 and December 2018. The clinical features and outcome data at 3, 12, and 36 months after stroke were collected. Differences in outcomes and relationship between outcomes and risk factors were assessed. A total of 1,772 patients were included in our study (61.7% male, 38.3% female). The rates of mortality, recurrence, and dependency were 6.6, 12.6, and 12.6%, respectively, at 3 months after stroke onset. The corresponding rate rose rapidly at 36 months (23.2, 78.7, and 79.7%, respectively). We found the positive predictors associated outcomes at 3, 12, and 36 months after stroke onset. The relative risk (RR) with 95% confidential interval (CI) is 1.06 (1.02–1.10, P = 0.006) at 3 months, 1.06 (1.02–1.10, P = 0.003) at12 months, and 1.10 (1.05–1.15, P < 0.001) at 36 months after stroke onset for age; 1.09 (1.01–1.19, P = 0.029) at 12 months for fasting plasma glucose (FPG) level; 4.25 (2.14–8.43, P < 0.001) at 3 months, 4.95 (2.70–9.10, P < 0.001) at 12 months, and 4.82 (2.25–10.32, P < 0.001) at 36 months for moderate stroke; 7.56 (3.42–16.72, P < 0.001) at 3 months, 11.08 (5.26–23.34, P < 0.001) at 12 months, and 14.30 (4.85–42.11, P < 0.001) at 36 months for severe stroke, compared to mild stroke. Hypersensitive C-reactive protein (hs-CRP) level was an independent risk factor for mortality at different follow-up times, with the RR (95%) of 1.02 (1.01–1.02, P < 0.001) at 3 months, 1.01 (1.00–1.02, P = 0.002) at 12 months. White blood cell count (WBC) level was associated with both stroke recurrence (RR = 1.09, 95%CI: 1.01–1.18, P = 0.023) and dependency (RR = 1.10, 95%CI: 1.02–1.19, P = 0.018) at 3 months. In contrast, a higher level of low-density lipoprotein cholesterol (LDL-C) within the normal range was a protective factor for recurrence and dependency at shorter follow-up times, with the RR (95%) of 0.67 (0.51–0.89, P = 0.005) and 0.67 (0.50–0.88, P = 0.005), respectively. These findings suggest that it is necessary to control the risk factors of LAA to reduce the burden of LAA stroke. Especially, this study provides a new challenge to explore the possibility of lowering LDL-C level for improved stroke prognosis.

Identification of Circular RNA hsa_circ_0001599 as a Novel Biomarker for Large-Artery Atherosclerotic Stroke

Circular RNAs (circRNAs) are a recently discovered noncoding RNA isoform capable of regulating neurological disease incidence. The present study was designed to characterize the circRNA expression profiles present in large-artery atherosclerosis (LAA)-type acute ischemic stroke patients and to detect biomarkers suitable for LAA-stroke detection. Using a RNA-seq-based approach, we characterized circRNA expression profiles in five LAA-stroke patients and four controls. We confirmed the differential expression of target circRNAs through quantitative real-time polymerase chain reaction (qRT-PCR), and used Gene Ontology and Kyoto Encyclopedia of Genes and Genomes pathway enrichment analyses to explore their functional roles. The diagnostic value of specific circRNAs was evaluated through a receiver operating characteristic (ROC) curve analysis. We identified 182 upregulated and 176 downregulated circRNAs in LAA-stroke patients and confirmed the differential expression of six circRNAs through qRT-PCR. These differentially expressed circRNAs are primarily associated with chromatin modification, autophagy, platelet activation, and neural precursor cell proliferation. The hsa_circRNA_0001599 expression levels were positively correlated with the National Institutes of Health Stroke Scale scores and infarct volumes, with an ROC analysis of hsa_circRNA_0001599 in LAA-stroke, yielding an area under the curve of 0.805 (95% confidence interval: 0.748-0.862; p < 0.001), consistent with sensitivity and specificity values of 64.41% and 89.93%, respectively, for the diagnosis of LAA-stroke. A transcriptome-wide survey of differential circRNA expression in LAA-stroke patients revealed hsa_circRNA_0001599 as a putative circRNA biomarker of LAA-stroke diagnosis.

Blood Neutrophil/Lymphocyte Ratio Is Associated With Cerebral Large-Artery Atherosclerosis but Not With Cerebral Small-Vessel Disease

Background and Objective: The blood neutrophil/lymphocyte ratio (NLR) is a marker of peripheral inflammation, with a high NLR associated with an increased risk of cardiovascular events and poor prognosis in ischemic stroke. However, few data are available on the differential impact of the blood NLR on different silent cerebral vascular pathologies, including cerebral large-artery atherosclerosis (LAA) and cerebral small-vessel disease (CSVD), in neurologically healthy individuals.

Methods: We evaluated cardiovascular risk factors, brain magnetic resonance imaging (MRI), and MR angiography of 950 individuals without any neurological diseases. The study participants were divided into three groups according to NLR tertile (low, middle, and high). The presences of extracranial (EC) and intracranial (IC) atherosclerosis were considered to indicate LAA on brain MR angiography. The presences of silent lacunar infarction (SLI) and cerebral white matter hyperintensities (WMHs) were analyzed as indices of CSVD on brain MRI.

Results: In univariate analysis, the high NLR tertile group showed a high prevalence of old age, hyperlipidemia, and renal dysfunction and higher fasting glucose. Multivariable logistic regression analysis revealed that indices of LAA (EC atherosclerosis [odds ratio: 1.88; 95% confidence interval: 1.14–3.09; p = 0.01] and IC atherosclerosis [odds ratio: 1.87; 95% confidence interval: 1.15–3.06; p = 0.01]) were more prevalent in the highest NLR tertile group than in the lowest NLR tertile group after adjustment for cardiovascular risk factors. However, no significant differences were found in the prevalence of CSVD indices (SLI and WMHs) among the three NLR tertile groups.

Conclusions: A high NLR is associated with the development of cerebral LAA but not CSVD.

Clinical Features of Embolic Stroke of Undetermined Source

Background and Objective: One-third of ischemic strokes have no identifiable cause following standard evaluation. In 2014, researchers have proposed the concept of Embolic Stroke of Undetermined Source (ESUS). The purpose of this study was to report the clinical characteristics of ESUS and its difference from cardiogenic embolism (CE), large-artery atherosclerosis (LA), and small-artery occlusion lacunar (SA).

Methods: Acute ischemic stroke (AIS) patients admitted to the department of Beijing Haidian Hospital from January 2017 to December 2017 were prospectively and consecutively enrolled. Base-line characteristics were collected. Stroke etiologies were presented and compared. We compared the clinical features and infarct sites of patients with acute cerebral infarction of different etiologies.

Results: A total of 119 AIS patients were analyzed in the study. There were 33 (27.73%) cases in ESUS group, 11 (9.24%) cases in CE group, 45 (37.82%) cases in LAA group and 30 (25.21%) cases in SA group. There were significant differences between the ESUS group and the CE group in the NIHSS score [3 (1.5–5) vs. 6 (2–20), p = 0.007], Modified Rankin Score [19, (57.58) vs. 9, (81.82), p = 0.008], hemorrhagic transformation [0, (0) vs. 5, (45.45), p < 0.001], and left atrial diameter [37.09 ± 3.16 vs. 41.73 ± 5.00, p = 0.001]. ESUS group and LA group have different mRS scores [19, (57.58) vs. 42, (93.33), p < 0.001]. ESUS group and SA group have different mRS scores [19, (57.58) vs. 28, (93.33), p = 0.001]. During 1 year follow-up, there were 5 cases (15.15%) in ESUS group, 3 cases (27.27%) in CE group, 3 cases (6.67%) in LA group, and 1 case (3.33%) in SA group with ischemic stroke (cerebral infarction or transient ischemic attack).

Conclusion: ESUS is more similar to atherosclerotic cerebral infarction in clinical features, but the distribution of lesions is more similar to cardiogenic embolism, suggesting that the pathogenesis of ESUS needs to be further explored.

Study of the Inflammatory Mechanisms in Hyperhomocysteinemia on Large-Artery Atherosclerosis Based on Hypersensitive C-Reactive Protein-A Study from Southern China

OBJECTIVE

To study the inflammatory mechanism of hyperhomocysteinemia on large-artery atherosclerosis based on hypersensitive C-reactive protein in patients.

METHODS

In all, 153 inpatients and 1357 physical examinees were selected. The levels of homocysteine were compared between the carotid/intracranial artery stenosis group and the nonstenosis group, between the carotid artery unstable plaque group and the nonplaque group, and between the intima-media thickness (IMT) greater than or equal to 1 group and the normal IMT group. The hypersensitive C-reactive protein levels were compared between the lacunar infarction (LI) group and the nonstroke control group and between the unstable plaque group and the nonplaque group.

RESULTS

Homocysteine level was significantly higher in the carotid/intracranial artery stenosis group than in the nonstenosis group, in the LI group than in the inpatient nonstroke group, and in the IMT greater than or equal to 1 group than in the normal IMT group. The hypersensitive C-reactive protein level was significantly higher in the LI group than in the nonstroke group and in the unstable plaque group than in the nonplaque group.

CONCLUSIONS

Hyperhomocysteinemia may aggravate the development of IMT, carotid atherosclerotic plaque instability, and carotid/intracranial artery stenosis by increasing inflammation, ultimately leading to the occurrence of LI. Hyperhomocysteinemia-induced inflammation mechanism warrants further study.

Bridging Therapy Versus Direct Mechanical Thrombectomy in Patients with Acute Ischemic Stroke due to Middle Cerebral Artery Occlusion: A Clinical- Histological Analysis of Retrieved Thrombi

Mechanical thrombectomy (MT) is effective in managing patients with acute ischemic stroke (AIS) caused by large-vessel occlusions and allows for valuable histological analysis of thrombi. However, whether bridging therapy (pretreatment with intravenous thrombolysis before MT) provides additional benefits in patients with middle cerebral artery (MCA) occlusion remains unclear. Therefore, this study aimed to compare the effects of direct MT and bridging therapy, and to elucidate the correlation between thrombus composition and stroke subtypes. Seventy-three patients with acute ischemic stroke who received MT, were eligible for intravenous thrombolysis, and had MCA occlusion were included. We matched 21 direct MT patients with 21 bridging therapy patients using propensity score matching and compared their 3rd-month clinical outcomes. All MCA thrombi (n = 45) were histologically analyzed, and the red blood cell (RBC) and fibrin percentages were quantified. We compared the clot composition according to stroke etiology (large-artery atherosclerosis and cardioembolism) and intravenous thrombolysis application. The baseline characteristics showed no difference between groups except for a higher atrial fibrillation rate and NIHSS score on admission in the direct MT group. We performed a supportive analysis using propensity score matching but could not find any differences in the functional outcome, mortality, and intracerebral hemorrhage. In the histological clot analysis, the cardioembolic clots without intravenous thrombolysis pretreatment had higher RBC (P = 0.042) and lower fibrin (P = 0.042) percentages than the large-artery atherosclerosis thrombi. Similar findings were observed in the thrombi treated with recombinant tissue plasminogen activator (P = 0.012). In conclusion, there was no difference in the functional outcomes between the direct MT and bridging therapy groups. However, randomized trials are needed to elucidate the high ratio of cardioembolism subtype in our group of patients. The histological MCA thrombus composition differed between cardioembolism and large-artery atherosclerosis, and this finding provides valuable information on the underlying pathogenesis and thrombus origin.

Association of G-protein coupled purinergic receptor P2Y2 with ischemic stroke in a Han Chinese population of North China

The G-protein-coupled purinergic receptor P2Y2 (P2RY2) plays an important role in the mechanism of atherosclerosis, which is relevant to ischemic stroke. This retrospective case-control study aimed to assess the relationship between P2RY2 gene polymorphisms and ischemic stroke risk in the northern Han Chinese population. In this study, clinical data and peripheral blood specimens were collected from 378 ischemic stroke patients and 344 controls. The ischemic stroke participants were recruited from the First Affiliated Hospital of China Medical University and the First Affiliated Hospital of Liaoning Medical University. The controls were recruited from the Health Check Center at the First Affiliated Hospital of China Medical University. Ischemic stroke patients were divided into two subgroups according to the Trial of ORG 10172 in Acute Stroke Treatment (TOAST) classification: large-artery atherosclerosis (n = 178) and small-artery occlusion (n = 200) strokes. All subjects were genotyped for three single nucleotide polymorphisms (rs4944831, rs1783596, and rs4944832) in the P2RY2 gene using peripheral venous blood samples. The distribution of the dominant rs4944832 phenotype (GG vs. GA+AA) differed significantly between small-artery occlusion patients and control subjects (odds ratio (OR) = 1.720, 95% confidence interval (CI): 1.203–2.458, P < 0.01). Multivariable logistic regression analysis revealed that the GG genotype of rs4944832 was significantly more prevalent in small-artery occlusion patients than in control subjects (OR = 1.807, 95% CI: 1.215–2.687, P < 0.01). The overall distribution of the haplotype established by rs4944831-rs1783596-rs4944832 was significantly different between ischemic stroke patients and controls (P < 0.01). In ischemic stroke patients, the frequency of the G-C-G haplotype was significantly higher than in control subjects (P = 0.028), whereas the frequency of the T-C-A haplotype was lower than in control subjects (P = 0.047). These results indicate that the G-C-G haplotype of P2RY2 is a susceptibility haplotype for ischemic stroke. In addition, the GG genotype of rs4944832 may be associated with the development of small-artery occlusion in the northern Han Chinese population. The study protocol was approved by the Ethics Committee of the First Affiliated Hospital of China Medical University on February 20, 2012 (No. 2012-38-1) and the First Affiliated Hospital of Liaoning Medical University, China, on March 1, 2013 (No. 2013-03-1). All participants gave their informed consent. This trial was registered with the ISRCTN Registry (ISRCTN11439124) on October 24, 2018. Protocol version (1.0).

Can high uric acid levels be an independent risk factor for acute ischemic stroke due to large-artery atherosclerosis?

Background and purpose

Uric acid is a molecule that is known to act as a natural antioxidant in acute oxidative stress conditions such as acute ischemic stroke (AIS). Although there are several studies on the prognostic value of serum uric acid (UA) level, especially the AIS, its importance in ischemic stroke is still controversial. Our aim in this study is to investigate whether the serum UA level is an indicative biomarker in the large-artery atherosclerosis in the AIS etiology.

Methods

Of the patients admitted to Sakarya University Training and Research Hospital Department of Neurology between January 2017 and November 2017, 91 hospitalized patients, who had AIS diagnosis and had their uric acid levels measured, were analyzed retrospectively. Patients with diabetes mellitus (DM), hypertension (HT), smoking habit, obesity, gout, hyperlipidemia (HL) and renal failure were excluded from the study. Patients were classified as anterior system and posterior system infarct. Then, patients were divided into two groups, one with internal carotid artery (ICA) > 50% stenosis and the other with ICA < 50% stenosis according to carotid-vertebral artery doppler USG examination performed for etiology. Serum UA, total bilirubin, direct bilirubin and indirect bilirubin levels of both groups were statistically compared.

Results

In the comparison of serum UA values of ICA>50% stenosis and ICA<50% stenosis group of AIS patients, a statistically significant difference was found between the UA levels (p<0.000), but there was no difference between total bilirubin, direct bilirubin and indirect bilirubin values (p>0.05).

Conclusion

High uric acid levels can be considered an independent, indicative risk factor for large-artery disease in AIS.

Gender Gap and Risk Factors for Poor Stroke Outcomes: A Single Hospital-Based Prospective Cohort Study

BACKGROUND

This study intended to investigate whether etiological stroke subtypes and their corresponding major risk factors have differential effects on outcomes between genders.

PATIENTS AND METHODS

We enrolled 403 consecutive patients with first-ever acute ischemic stroke (170 women, 233 men), from a referral hospital in Taiwan over a 2-year period. Gender differences in demographics, vascular risk factors, access to health care, etiological stroke subtypes, stroke severity, and outcomes were examined. The primary outcome variable of the study was any unfavorable outcome due to acute ischemic stroke, defined as a modified Rankin Scale score of 3 or higher at 90 days after stroke. Multivariable logistic regression models were used to identify predictors of poor outcomes.

RESULTS

There were no gender disparities in baseline severity, stroke subtypes, access to health care, and medical comorbidities. Although women had poorer outcomes, female gender was not a predictor of unfavorable outcomes. Important predictors included age of 75years or older (odds ratio [OR] = 2.67; 95% confidence interval [CI], 1.46-4.90), National Institutes of Health Stroke Scale greater than or equal to 8 (OR = 8.38; 95% CI, 4.61-15.2), lack of cohabitation (OR = 2.13; 95% CI, 1.26-3.61), subtypes of cardioembolism (OR = 2.76; 95% CI, 1.29-5.93), and large-artery atherosclerosis (OR = 2.93; 95% CI, 1.47-5.85). In subgroup analyses, the gender-specific independent predictors were cardioembolism (OR = 7.42; 95% CI, 2.21-24.9) or atrial fibrillation (OR = 3.57; 95% CI, 1.31-9.74) in women, and large-artery atherosclerosis (OR = 3.35; 95% CI, 1.30-8.64) or symptomatic large-artery stenosis (OR = 3.42; 95% CI, 1.69-6.96) in men. The differential effects of these predictors according to gender were revealed by interaction tests.

CONCLUSION

Atrial fibrillation and symptomatic large-artery stenosis are predictors of poor stroke outcomes in women and men, respectively.

High serum uric acid levels are a protective factor against unfavourable neurological functional outcome in patients with ischaemic stroke

Objective

We aimed to evaluate the association between serum uric acid levels at the onset and prognostic outcome in patients with acute ischaemic stroke.

Methods

We retrospectively analysed the outcomes of 1166 patients with ischaemic stroke who were hospitalized in our centre during August 2008 to November 2012. Correlations of serum uric acid levels and prognostic outcomes were analysed.

Results

Men had higher serum uric acid levels and better neurological functional outcomes compared with women. There was a strong negative correlation between serum uric acid levels and unfavourable neurological functional outcomes. Generalized estimated equation analysis showed that a higher serum uric acid level (>237 µmol/L) was a protective factor for neurological functional outcome in male, but not female, patients. Among five trial of ORG 10172 in acute stroke treatment classification subtypes, only patients with the large-artery atherosclerosis subtype had a significant protective effect of serum uric acid levels on neurological outcome.

Conclusions

Our study shows that high serum uric acid levels are a significant protective factor in men and in the large-artery atherosclerosis subtype in patients with ischaemic stroke. This is helpful for determining the prognostic value of serum uric acid levels for neurological outcome of acute ischaemic stroke.

Associations between thromboxane A synthase 1 gene polymorphisms and the risk of ischemic stroke in a Chinese Han population

Thromboxane A synthase 1 (TBXAS1) catalyses the synthesis of thromboxane A2 (TXA2), which plays an important role in the pathogenesis of ischemic stroke. Thus, the TBXAS1 gene was investigated as a candidate gene involved in the formation of atherosclerosis. This case-control study collected peripheral blood specimens and clinical data of 370 ischemic stroke patients and 340 healthy controls in the Northern Chinese Han population from October 2010 to May 2011. Two TBXAS1 single-nucleotide polymorphisms, rs2267682 and rs10487667, were analyzed using a SNaPshot Multiplex sequencing assay to explore the relationships between the single-nucleotide polymorphisms in TBXAS1 and ischemic stroke. The TT genotype frequency and T allele frequency of rs2267682 in the patients with ischemic stroke were significantly higher than those in the controls (P < 0.01 and P = 0.02). Furthermore, compared with the GG + GT genotype, the TT rs2267682 genotype was associated with increased risk of ischemic stroke (odds ratio (OR) = 1.80, 95% confidence interval (CI): 1.16–2.79, P < 0.01). Multivariate logistic analysis with adjustments for confounding factors revealed that rs2267682 was still associated with ischemic stroke (OR = 1.94, 95% CI : 1.13–3.33, P = 0.02). The frequency of the T-G haplotype in the patients was significantly higher than that in the controls according haplotype analysis (OR = 1.49, 95% CI: 1.10–2.00, P < 0.01). These data reveal that the rs2267682 TBXAS1 polymorphism is associated with ischemic stroke. The TT genotype of TBXAS1 and T allele of rs2267682 increase susceptibility to ischemic stroke in this Northern Chinese Han population. The protocol has been registered with the Chinese Clinical Trial Registry (registration number: ChiCTR-COC-17013559).

Clinical Study of 27 Patients with Medial Medullary Infarction

BACKGROUND

Medial medullary infarction (MMI) is a rare ischemic stroke. Frequency of each neurological finding in MMI was different in each study.

METHODS

We retrospectively evaluated the medical records of patients with cerebral infarction who were admitted between March 1998 and October 2015. Patients in our study were diagnosed as having MMI by magnetic resonance image examination.

RESULTS

Of 2727 patients with ischemic stroke, 27 patients (20 males and 7 females) had MMI. The MMI was complicated by infarcts located in the pons (n = 6), cerebellum (n = 2), and lateral medulla (n = 1). One patient had bilateral MMI. Large-artery atherosclerosis was the most common etiology. Motor weakness of the extremities was the most common neurological finding. Diminished contralateral superficial sensation was more common than diminished contralateral vibratory sensation, and these 2 types of sensory disturbance were often complicated. The patients with large MMI significantly more often accompanied diminished touch (P = .003), pain (P = .017), and vibratory (P = .019) sensation. Facial weakness was shown more common contralateral to the infarcts than ipsilateral (n = 8 contralateral, n = 1 ipsilateral). Lingual palsy was also more common contralateral to the lesions (n = 3 contralateral, n = 1 ipsilateral). One patient alone fulfilled the classical Dejerine triad.

CONCLUSIONS

In MMI, motor weakness of extremities was commonly shown, and complication of diminished sensations indicated the large infarcts. As for facial weakness and lingual palsy, the supranuclear type was more prominent than the infranuclear type.

Risk Factors of Neurological Deterioration in Patients with Cerebral Infarction due to Large-Artery Atherosclerosis

BACKGROUND

In some patients with acute ischemic stroke, neurological deterioration (ND) is observed, and it is difficult to predict at the time of admission. Especially in some patients with large-artery atherosclerosis (LAA), aggressive medical treatments and surgical interventions might be helpful to prevent ND. Therefore, we investigated factors associated with ND in patients with LAA.

METHODS

We studied patients with LAA who were admitted to our hospital. We divided them into 2 groups with (group 1) and without deterioration (group 2), and evaluated their medical records, risk factors, and radiological findings, such as number of diffusion-positive lesion and degree of stenosis.

RESULTS

Our study population consisted of 171 patients; 71 (41.5%) did and 100 (58.5%) did not suffer deterioration. By univariate analysis, blood pressure (BP), heart rate, National Institutes of Health Stroke Scale (NIHSS) score, number of diffusion-positive lesion, count of red blood cell, high-density lipoprotein, and degree of stenosis differed significantly between the 2 groups. By multivariate analysis, systolic BP (≥170 mm Hg, odds ratio: 7.20, P <.001) was associated with ND. Furthermore, number of diffusion-weighted image (DWI)-positive lesion (≥8), degree of stenosis (>80.0%), and NIHSS score (≥4) were also independent factors associated with ND.

CONCLUSIONS

High BP, severity of neurological deficit at the time of admission, and radiological findings, such as degree of stenosis and number of DWI-positive lesion, are independently associated with ND in patients with LAA.

Anti-inflammatory and anti-thrombogenic effects of atorvastatin in acute ischemic stroke

Atorvastatin decreases inflammation and thrombogenesis in patients with carotid artery plaque. Atorvastatin is administered to lower lipid levels, but its anti-inflammatory and anti-thrombogenic effects remain unclear. Eighty-nine patients from northeastern China with acute ischemic stroke caused by large-artery atherosclerosis were randomly divided into the study and control groups. All patients received routine treatment, including antiplatelet therapy, circulatory support, and symptomatic treatment. The study group (n = 43) also received daily atorvastatin 20 mg/d, and the control group (n = 46) received daily placebo pills containing glucose. After 4 weeks, the levels of C-reactive protein, fibrinogen, and D-dimer were significantly lower in the study group than in the control group. Decreases in the levels of C-reactive protein, fibrinogen, and D-dimer were not associated with decreases in the levels of triacylglycerol and low-density lipoprotein cholesterol. These results suggest that atorvastatin reduces inflammation and thrombogenesis independent of its lipid-lowering effects in patients with acute ischemic stroke caused by large-artery atherosclerosis.

The arachidonate 5-lipoxygenase-activating protein (ALOX5AP) gene SG13S114 polymorphism and ischemic stroke in Chinese population: a meta-analysis

Previous studies have indicated that the arachidonate 5-lipoxygenase-activating protein (ALOX5AP) gene SG13S114 polymorphism is associated with risk of ischemic stroke (IS), but the results remain inconclusive even in Chinese population. A meta-analysis of 10 case-control studies was conducted on the relationship between ALOX5AP SG13S114 polymorphism and susceptibility to IS in Chinese population published domestically and abroad from September 2007 to December 2012. Data were extracted by two authors and pooled odds ratios (ORs) and 95% confidence intervals (CIs) were calculated. Meta-analysis results showed that the significant association between SG13S114 variant and IS was found under the allelic (OR=0.87, 95% CI: 0.80-0.96, P=0.004), dominant (OR=0.75, 95% CI: 0.62-0.92, P=0.005), and recessive (OR=0.89, 95% CI: 0.82-0.97, P=0.005) genetic models in Chinese population. In subgroup meta-analysis, SG13S114 variant and atherothrombotic stroke, rather than lacunar stroke, showed the significant association under the allelic (OR=0.86, 95% CI: 0.80-0.92, P<0.0001), dominant (OR=0.72, 95% CI: 0.57-0.91, P=0.006), and recessive (OR=0.86, 95% CI: 0.78-0.95, P=0.002) models. ALOX5AP SG13S114 polymorphism is associated with susceptibility to IS in Chinese population.

Treatment of acute ischemic stroke: beyond thrombolysis and supportive care

The initial therapeutic approach to acute ischemic stroke consists of thrombolytic therapy and early initiation of supportive care, usually commenced prior to the determination of the underlying stroke etiology. Varying stroke mechanisms may call for specific, etiology-based treatment. The majority of strokes result from cardioembolism, large-vessel atherothromboembolism, and small-vessel occlusive disease. There are scant data to support the use of acute anticoagulation therapy over anti-platelet therapy in cardioembolic stroke and large-vessel atherosclerosis, although it may be reasonable in a certain subset of patients. However, augmentation of blood flow with early surgery, stenting, or induced hypertension, may play a role in patients with large artery stenosis. The less commonly identified stroke mechanisms may warrant special consideration in treatment. Controversy remains regarding the optimal anti-thrombotic treatment of arterial dissection. Reversible cerebral vasoconstriction syndrome may benefit from therapy with calcium channel blockers, high-dose steroids, or magnesium, although spontaneous recovery may occur. Inflammatory vasculopathies, such as isolated angiitis of the central nervous system and temporal arteritis, require prompt diagnosis as the mainstay of therapy is immunosuppression. Cerebral venous thrombosis is a rare cause of stroke, but one that needs early identification and treatment with anticoagulation. Rapid determination of stroke mechanism is essential for making these critical early treatment decisions.