Type 2 diabetes is associated with a worse functional outcome of ischemic stroke

Evaluation of Middle Cerebral Artery Culprit Plaque Inflammation in Ischemic Stroke Using CAIPIRINHA-Dixon-TWIST Dynamic Contrast-Enhanced Magnetic Resonance Imaging

BACKGROUND

Middle cerebral artery (MCA) plaques are a leading cause of ischemic stroke (IS). Plaque inflammation is crucial for plaque stability and urgently needs quantitative detection.

PURPOSE

To explore the utility of Controlled Aliasing in Parallel Imaging Results in Higher Acceleration (CAIPIRINHA)-Dixon-Time-resolved angiography With Interleaved Stochastic Trajectories (TWIST) (CDT) dynamic contrast-enhanced MRI (DCE-MRI) for evaluating MCA culprit plaque inflammation changes over stroke time and with diabetes mellitus (DM).

STUDY TYPE

Prospective.

POPULATION

Ninety-four patients (51.6 ± 12.23 years, 32 females, 23 DM) with acute IS (AIS; N = 43) and non-acute IS (non-AIS; 14 days < stroke time ≤ 3 months; N = 51).

FIELD STRENGTH/SEQUENCE

3-T, CDT DCE-MRI and three-dimensional (3D) Sampling Perfection with Application optimized Contrast using different flip angle Evolution (3D-SPACE) T1-weighted imaging (T1WI).

ASSESSMENT

Stroke time (from initial IS symptoms to MRI) and DM were registered. For 94 MCA culprit plaques, Ktrans from CDT DCE-MRI and enhancement ratio (ER) from 3D-SPACE T1WI were compared between groups with and without AIS and DM.

STATISTICAL TESTS

Shapiro-Wilk test, Bland-Altman analysis, Passing and Bablok test, independent t-test, Mann-Whitney U test, Chi-squared test, Fisher's exact test, receiver operating characteristics (ROC) with the area under the curve (AUC), DeLong's test, and Spearman rank correlation test with the P-value significance level of 0.05.

RESULTS

Ktrans and ER of MCA culprit plaques were significantly higher in AIS than non-AIS patients (Ktrans = 0.098 s-1 vs. 0.037 s-1; ER = 0.86 vs. 0.55). Ktrans showed better AUC for distinguishing AIS from non-AIS patients (0.87 vs. 0.75) and stronger negative correlation with stroke time than ER (r = -0.60 vs. -0.34). DM patients had significantly higher Ktrans and ER than non-DM patients in IS and AIS groups.

DATA CONCLUSION

Imaging by CDT DCE-MRI may allow to quantitatively evaluate MCA culprit plaques over stroke time and DM.

EVIDENCE LEVEL

2 TECHNICAL EFFICACY: Stage 2.

Combined polygenic scores for ischemic stroke risk factors aid risk assessment of ischemic stroke

BACKGROUND

Current risk assessment for ischemic stroke (IS) is limited to clinical variables. We hypothesize that polygenic scores (PGS) of IS (PGSIS) and IS-associated diseases such as atrial fibrillation (AF), venous thromboembolism (VTE), coronary artery disease (CAD), hypertension (HTN), and Type 2 diabetes (T2D) may improve the performance of IS risk assessment.

METHODS

Incident IS was followed for 479,476 participants in the UK Biobank who did not have an IS diagnosis prior to the recruitment. Lifestyle variables (obesity, smoking and alcohol) at the time of study recruitment, clinical diagnoses of IS-associated diseases, PGSIS, and five PGSs for IS-associated diseases were tested using the Cox proportional-hazards model. Predictive performance was assessed using the C-statistic and net reclassification index (NRI).

RESULTS

During a median average 12.5-year follow-up, 8374 subjects were diagnosed with IS. Known clinical variables (age, gender, clinical diagnoses of IS-associated diseases, obesity, and smoking) and PGSIS were all independently associated with IS (P < 0.001). In addition, PGSIS and each PGS for IS-associated diseases was also independently associated with IS (P < 0.001). Compared to the clinical model, a joint clinical/PGS model improved the C-statistic for predicting IS from 0.71 to 0.73 (P < 0.001) and significantly reclassified IS risk (NRI = 0.017, P < 0.001), and 6.48% of subjects were upgraded from low to high risk.

CONCLUSIONS

Adding PGSs of IS and IS-associated diseases to known clinical risk factors statistically improved risk assessment for IS, demonstrating the supplementary value of inherited susceptibility measurement . However, its clinical utility is likely limited due to modest improvements in predictive values.

The SGLT2 inhibitor Empagliflozin promotes post-stroke functional recovery in diabetic mice

Type-2 diabetes (T2D) worsens stroke recovery, amplifying post-stroke disabilities. Currently, there are no therapies targeting this important clinical problem. Sodium-glucose cotransporter 2 inhibitors (SGLT2i) are potent anti-diabetic drugs that also efficiently reduce cardiovascular death and heart failure. In addition, SGLT2i facilitate several processes implicated in stroke recovery. However, the potential efficacy of SGLT2i to improve stroke recovery in T2D has not been investigated. Therefore, we determined whether a post-stroke intervention with the SGLT2i Empagliflozin could improve stroke recovery in T2D mice. T2D was induced in C57BL6J mice by 8 months of high-fat diet feeding. Hereafter, animals were subjected to transient middle cerebral artery occlusion and treated with vehicle or the SGLTi Empagliflozin (10 mg/kg/day) starting from 3 days after stroke. A similar study in non diabetic mice was also conducted. Stroke recovery was assessed using the forepaw grip strength test. To identify potential mechanisms involved in the Empagliflozin-mediated effects, several metabolic parameters were assessed. Additionally, neuronal survival, neuroinflammation, neurogenesis and cerebral vascularization were analyzed using immunohistochemistry/quantitative microscopy. Empagliflozin significantly improved stroke recovery in T2D but not in non-diabetic mice. Improvement of functional recovery was associated with lowered glycemia, increased serum levels of fibroblast growth factor-21 (FGF-21), and the normalization of T2D-induced aberration of parenchymal pericyte density. The global T2D-epidemic and the fact that T2D is a major risk factor for stroke are drastically increasing the number of people in need of efficacious therapies to improve stroke recovery. Our data provide a strong incentive for the potential use of SGLT2i for the treatment of post-stroke sequelae in T2D.

Increased Two-Hour Post-Load Plasma Glucose Fluctuation Corresponds with Worse Clinical Prognoses among Acute Ischemic Stroke Patients without a History of Diabetes Mellitus

INTRODUCTION

This study aimed to evaluate the relationship between 2-h post-load minus fasting plasma glucose (2hPG-FPG) and 1-year clinical outcomes, such as death, stroke recurrence, and modified Rankin Scale (mRS) ≥2-3 among acute ischemic stroke (AIS) patients without diabetes mellitus (DM) history.

METHODS

1,214 AIS patients without DM history, obtained from ACROSS-China, were divided into 4 quartiles, based on 2hPG-FPG measurements obtained 14 days post-admission. Four models were constructed using multivariate Cox and logistic regression analyses, based on the inclusion of age, gender, trial of ORG 10172 in acute stroke treatment, NIH Stroke Scale scores (model 1), plus 10 other clinical parameters (model 2), plus newly diagnosed DM (NDDM) post-admission (model 3), plus 2hPG and FPG (model 4). Associations found from those 4 models between 2hPG-FPG and 1-year clinical outcomes were confirmed via stratification, multiplicative interaction, sensitivity, and restricted cubic spline analyses.

RESULTS

The highest quartile of 2hPG-FPG, after adjusting for variables, such as stroke severity (model 2), was independently associated with death, stroke recurrence, and mRS ≥2-3 (odds ratio [OR] = 3.95, 2.96, 4.15, and 4.83, respectively, all p < 0.0001). Increased 2hPG-FPG remained independently associated with mRS ≥2-3 in models 3-4, as well as increased mRS ≥2 under stratification analyses among both non-NDDM and NDDM patients.

CONCLUSION

2hPG-FPG is a relatively specific indicator of poorer 1-year clinical prognoses among AIS patients, independent of NDDM, 2hPG, and FPG post-hospital admission. Therefore, the oral glucose tolerance test could be a useful approach for detecting a higher likelihood for developing poorer prognoses among patients without DM history.

Risk of Stroke and Cardiovascular Disease According to Diabetes Mellitus Status

The purpose of this study was to investigate the importance of prevention and management of diabetes by analyzing stroke and cardiovascular disease (CVD) incidence among people with diabetes. This secondary analysis of the Korea National Health and Nutrition Examination Survey Ⅶ (2016-2018) data included 15,039 adults. Diabetes status was significantly associated with sex, age, marital status, household size, education level, employment status, household income, hypertension, dyslipidemia, stroke, CVD, osteoarthritis, osteoporosis, kidney failure, depression, level of stress, smoking, drinking, body mass index, weight control, and the number of days of walking per week; however, it was not associated with rheumatoid arthritis. Stroke and CVD risk significantly increased in the presence of diabetes (by 4.123 times and 3.223 times, respectively). The incidences of stroke and CVD were significantly higher among participants with diabetes than among those without diabetes. Thus, preventing and systematically managing diabetes is crucial to reducing related complications and mortality.

Effects of diabetes mellitus complicated by admission hyperglycemia on clot histological composition and ultrastructure in patients with acute ischemic stroke

Background

Type 2 diabetes mellitus (T2DM) affects the occurrence and prognosis of acute ischemic stroke (AIS). However, the impact of diabetes on thrombus characteristics is unclear. The relationship between the composition and ultrastructure of clots and DM with admission hyperglycemia was investigated.

Methods

Consecutive patients with AIS who underwent endovascular thrombus retrieval between June 2017 and May 2021 were recruited. The thrombus composition and ultrastructure were evaluated using Martius scarlet blue stain and scanning electron microscopy. Clot perviousness was evaluated via thrombus attenuation increase on computed tomography angiography (CTA) versus non-contrast CT. Patients with admission hyperglycemia DM (ahDM) and those without DM (nonDM) were compared in terms of thrombus composition, ultrastructure, and perviousness.

Results

On admission, higher NIHSS scores (17 vs. 12, respectively, p = 0.015) was evident in ahDM patients. After the 90-day follow-up, the rates of excellent outcomes (mRS 0–1) were lower in patients with ahDM (16.6%, p = 0.038), but functional independence (mRS 0–2) and handicapped (mRS 3–5) were comparable between patients with ahDM and nonDM. The outcome of mortality was higher in patients with ahDM (33.3%, p = 0.046) than in nonDM patients. Clots in patients with ahDM had more fibrin (39.4% vs. 25.0%, respectively, p = 0.007), fewer erythrocyte components (21.2% vs. 41.5%, respectively, p = 0.043), equivalent platelet fraction (27.7% vs. 24.6%, respectively, p = 0.587), and higher WBC counts (4.6% vs. 3.3%, respectively, p = 0.004) than in nonDM patients. The percentage of polyhedral erythrocytes in thrombi was significantly higher in ahDM patients than in nonDM patients (68.9% vs. 45.6%, respectively, p = 0.007). The proportion of pervious clots was higher in patients nonDM than in patients with ahDM (82.61% vs. 40%, respectively, p = 0.026).

Conclusion

Patients with ahDM presented with greater stroke severity on admission and poorer functional outcomes after 3 months. Clots in patients with ahDM had more fibrin, leucocytes, and fewer erythrocyte components than in patients nonDM. The content of polyhedral erythrocytes and impervious clots proportion were significantly higher in thrombi of patients with AIS and ahDM. Further research is required to validate these findings.

Elevated Hemoglobin A1c Is Associated With Leaky Plaque Neovasculature as Detected by Dynamic Contrast-Enhanced Magnetic Resonance Imaging

BACKGROUND

Patients with diabetes have accelerated atherosclerosis progression, but the underlying mechanisms are not fully understood. Dynamic contrast-enhanced magnetic resonance imaging has allowed in vivo characterization of plaque neovasculature, which plays a critical role in plaque progression. We aimed to evaluate the impact of diabetes on carotid plaque neovasculature as assessed by dynamic contrast-enhanced magnetic resonance imaging.

METHODS

Patients with recent ischemic stroke and ipsilateral carotid plaque underwent multicontrast magnetic resonance imaging for characterizing plaque morphology and dynamic contrast-enhanced magnetic resonance imaging for pharmacokinetic parameters of plaque neovasculature, including transfer constant (Ktrans, reflecting flow, endothelial surface area, and permeability) and fractional plasma volume (νp).

RESULTS

Sixty-five patients were enrolled, including 30 patients with diabetes (years since diagnosis: median 5.0 [interquartile range, [3.0-12.0]) and 35 patients without diabetes. Subjects with diabetes had a greater plaque burden and a higher prevalence of high-risk characteristics. Additionally, carotid plaques in the subjects with diabetes showed higher Ktrans than those in the subjects without diabetes (0.100±0.048 min-1 versus 0.067±0.042 min-1, P=0.005) but νp was numerically lower in the subjects with diabetes (5.2±3.7% versus 6.2±4.3%, P=0.31). The association of diabetes with high Ktrans (β=0.033, P=0.005) was independent of patient and plaque characteristics and remained largely intact after adjusting for serum lipids, glucose, or hs-CRP (high-sensitivity C-reactive protein). However, it became nonexistent after adjusting for hemoglobin A1c (β=-0.010, P=0.49).

CONCLUSIONS

Dynamic contrast-enhanced magnetic resonance imaging of carotid plaques suggested that plaque neovasculature in patients with diabetes is leaky, indicating enhanced capability of bringing blood constituents and facilitating extravasation of inflammatory cells, erythrocytes, and plasma proteins. Leaky plaque neovasculature correlated with hemoglobin A1c and may play a role in accelerated atherosclerosis progression in diabetes.

New Drug Targets to Prevent Death Due to Stroke: A Review Based on Results of Protein-Protein Interaction Network, Enrichment, and Annotation Analyses

This study used established biomarkers of death from ischemic stroke (IS) versus stroke survival to perform network, enrichment, and annotation analyses. Protein-protein interaction (PPI) network analysis revealed that the backbone of the highly connective network of IS death consisted of IL6, ALB, TNF, SERPINE1, VWF, VCAM1, TGFB1, and SELE. Cluster analysis revealed immune and hemostasis subnetworks, which were strongly interconnected through the major switches ALB and VWF. Enrichment analysis revealed that the PPI immune subnetwork of death due to IS was highly associated with TLR2/4, TNF, JAK-STAT, NOD, IL10, IL13, IL4, and TGF-β1/SMAD pathways. The top biological and molecular functions and pathways enriched in the hemostasis network of death due to IS were platelet degranulation and activation, the intrinsic pathway of fibrin clot formation, the urokinase-type plasminogen activator pathway, post-translational protein phosphorylation, integrin cell-surface interactions, and the proteoglycan-integrin extracellular matrix complex (ECM). Regulation Explorer analysis of transcriptional factors shows: (a) that NFKB1, RELA and SP1 were the major regulating actors of the PPI network; and (b) hsa-mir-26-5p and hsa-16-5p were the major regulating microRNA actors. In conclusion, prevention of death due to IS should consider that current IS treatments may be improved by targeting VWF, the proteoglycan-integrin-ECM complex, TGF-β1/SMAD, NF-κB/RELA and SP1.

Carotid intima media thickness measurements coupled with stroke severity strongly predict short-term outcome in patients with acute ischemic stroke: a machine learning study

Acute ischemic stroke (IS) is one of the leading causes of morbidity, functional disability and mortality worldwide. The objective was to evaluate IS risk factors and imaging variables as predictors of short-term disability and mortality in IS. Consecutive 106 IS patients were enrolled. We examined the accuracy of IS severity using the National Institutes of Health Stroke Scale (NIHSS), carotid intima-media thickness (cIMT) and carotid stenosis (both assessed using ultrasonography with doppler) predicting IS outcome assessed with the modified Rankin scale (mRS) three months after hospital admission. Poor prognosis (mRS ≥ 3) at three months was predicted by carotid stenosis (≥ 50%), type 2 diabetes mellitus and NIHSS with an accuracy of 85.2% (sensitivity: 90.2%; specificity: 81.8%). The mRS score at three months was strongly predicted by NIHSS (β = 0.709, p < 0.001). Short-term mortality was strongly predicted using a neural network model with cIMT (≥ 1.0 mm versus < 1.0 mm), NIHSS and age, yielding an area under the receiving operator characteristic curve of 0.977 and an accuracy of 94.7% (sensitivity: 100.0%; specificity: 90.9%). High NIHSS (≥ 15) and cIMT (≥ 1.0 mm) increased the probability of dying with hazard ratios of 7.62 and 3.23, respectively. Baseline NIHSS was significantly predicted by the combined effects of age, large artery atherosclerosis stroke, sex, cIMT, body mass index, and smoking. In conclusion, high values of cIMT and NIHSS at admission strongly predict short-term functional impairment as well as mortality three months after IS, underscoring the importance of those measurements to predict clinical IS outcome.

Acute ischemic stroke with cervical internal carotid artery steno-occlusive lesion: multicenter analysis of endovascular approaches

BACKGROUND

Occlusion of the internal carotid artery (ICA), whether isolated or in the setting of a tandem lesion (TL) have a poor response to treatment with intravenous thrombolysis. Previous studies ​​have demonstrated the superiority of mechanical thrombectomy in the treatment of acute ischemic stroke (AIS) following large vessel occlusion, compared to standard intravenous fibrinolysis. The aim of our study was to describe endovascular treatment (EVT) in AIS due to isolated ICA occlusion or TL.

METHODS

We assessed the association between 90-day outcome and clinical, demographic, imaging, and procedure data in 51 consecutive patients with acute isolated ICA occlusion or TL who underwent EVT. We evaluated baseline NIHSS and mRS, ASPECTS, type of occlusion, stent placement, use of stent retrievers and/or thromboaspiration, duration of the procedure, mTICI, postprocedural therapy and complications.

RESULTS

A favorable 90-day outcome (mRS 0-2) was achieved in 34 patients (67 %) and was significantly associated with the use of dual antiplatelet therapy after the procedure (p = 0.008), shorter procedure duration (p = 0.031), TICI 2b-3 (p < 0.001) and lack of post-procedural hemorrhagic transformation (p = 0.001). Four patients did not survive, resulting in a mortality rate of 8 %.

CONCLUSIONS

Our study has shown that EVT in the treatment of AIS due to ICA occlusion is safe, and effective in determining a good functional outcome. ICA stenting led to good angiographic results and therapy with a glycoprotein IIb / IIIa inhibitor immediately after stent release did not result in a greater risk of hemorrhage. The use of post-procedural dual antiplatelet therapy was associated with favorable outcome, without a significant increase in hemorrhagic transformation.

Predictors of Functional Outcome in a Cohort of Hispanic Patients Using Exoskeleton Rehabilitation for Cerebrovascular Accidents and Traumatic Brain Injury

Traumatic brain injury (TBI) and cerebrovascular accidents (CVA) are two of the leading causes of disability in the United States. Robotic exoskeletons (RE) have been approved for rehabilitation by the Federal Drug Administration (FDA) for use after a CVA, and recently received approval for use in patients with TBI. The aim of the study was to determine which factors predict the improvement in functional independence measure (FIM) score after using RE rehabilitation in a population of patients with CVA or TBI. We carried out a retrospective chart-review analysis of the use of the RE (Ekso® GT) in the rehabilitation of patients with TBI and CVA using data from a single, private rehabilitation hospital for patients admitted and discharged between 01/01/2017 and 04/30/2020. From the medical records, we collected presentation date, Glasgow Coma Scale score (GCS) on the date of injury, rehabilitation start date, age, diabetes status on presentation (Yes or No), injury category (TBI or CVA), and both admission and discharge FIM scores. Matching algorithms resulted in one TBI patient matched to three CVA patients resulting in a sample size of 36. The diabetic and non-diabetic populations showed significant differences between age and days from injury to the start of rehabilitation. A multivariate linear regression assessed predictors for discharge motor FIM and found admission motor FIM score and total RE steps to be statistically significant predictors. For each point scored higher on the admission motor FIM the discharge FIM was increased by 1.19 FIM points, and for each 1,000 steps taken in the RE, the discharge motor FIM increased by three points. The type of acquired brain injury (CVA or TBI) was not found to affect functional outcome. The presented results show that key clinic-biologic factors including diabetic status, together with start to rehabilitation play key roles in discharge FIM scores for patients using RE. Clinical Trial Registration: ClinicalTrials.gov, NCT04465019.

Cerebral Autoregulation in Ischemic Stroke: From Pathophysiology to Clinical Concepts

Ischemic stroke (IS) is one of the most impacting diseases in the world. In the last decades, new therapies have been introduced to improve outcomes after IS, most of them aiming for recanalization of the occluded vessel. However, despite this advance, there are still a large number of patients that remain disabled. One interesting possible therapeutic approach would be interventions guided by cerebral hemodynamic parameters such as dynamic cerebral autoregulation (dCA). Supportive hemodynamic therapies aiming to optimize perfusion in the ischemic area could protect the brain and may even extend the therapeutic window for reperfusion therapies. However, the knowledge of how to implement these therapies in the complex pathophysiology of brain ischemia is challenging and still not fully understood. This comprehensive review will focus on the state of the art in this promising area with emphasis on the following aspects: (1) pathophysiology of CA in the ischemic process; (2) methodology used to evaluate CA in IS; (3) CA studies in IS patients; (4) potential non-reperfusion therapies for IS patients based on the CA concept; and (5) the impact of common IS-associated comorbidities and phenotype on CA status. The review also points to the gaps existing in the current research to be further explored in future trials.

A double-blind placebo-controlled clinical trial testing the effect of hyperbaric oxygen therapy on brain and cognitive outcomes of mildly cognitively impaired elderly with type 2 diabetes: Study design

INTRODUCTION

Type 2 diabetes (T2D) is a risk factor for dementia. Ischemia due to vascular pathology is hypothesized to be an underlying mechanism for this association. Hyperbaric oxygen therapy (HBOT) is a treatment in which oxygen-enriched air (up to 100%) is administered to patients in a chamber at a pressure above one atmosphere absolute. HBOT is approved for the treatment of T2D ischemic non-healing wounds. Evidence from animal studies and small clinical trials suggests that HBOT improves hypoxic/ischemic brain injuries, consequently inducing brain angiogensis, leading to cognitive improvement.

METHODS

We present the design of the first double-blind, placebo-controlled, clinical trial on brain and cognitive outcomes in elderly (n = 154) with T2D and mild cognitive impairment to compare the effects of HBOT versus sham (normal air with 1.1 ATA pressure in the first and last 5 minutes of the session). Eligible candidates are randomized with equal probability to HBOT and sham. Outcomes are assessed before and after treatment, and at 6- and 12-month follow-up. The primary cognitive outcome is global cognitive change, indexed by a composite sum of z-scores of four executive functions and four episodic memory tests. The primary neurobiological outcome is cerebral blood flow (CBF; via arterial spin labeling magnetic resonance imaging [ASL-MRI]) and cerebral glucose utilization via fluorodeoxyglucose positron emission tomography (FDG-PET). Secondary outcome measures are specific cognitive domains (executive function and episodic memory) and functional measures (Clinical Dementia Rating sum of boxes, activities of daily living). Efficacy analyses will be performed for the intent-to-treat sample.

DISCUSSION

Recent studies suggest that HBOT induces neuroplasticity and improves cognition in post-stroke and traumatic brain injury patients. However, its effect on cognition, cerebral blood flow, and brain glucose utilization in T2D patients at high dementia risk is yet to be determined. If effective, this study may provide strong evidence for the brain and cognitive benefits of HBOT in this population.

CD133+Exosome Treatment Improves Cardiac Function after Stroke in Type 2 Diabetic Mice

Cardiac complications post-stroke are common, and diabetes exacerbates post-stroke cardiac injury. In this study, we tested whether treatment with exosomes harvested from human umbilical cord blood derived CD133+ cells (CD133+Exo) improves cardiac function in type 2 diabetes mellitus (T2DM) stroke mice. Adult (3-4 m), male, BKS.Cg-m+/+Lepr^db/J (db/db, T2DM) and non-DM (db+) mice were randomized to sham or photothrombotic stroke groups. T2DM-stroke mice were treated with phosphate-buffered saline (PBS) or CD133+Exo (20 μg, i.v.) at 3 days after stroke. T2DM sham and T2DM+CD133+Exo treatment groups were included as controls. Echocardiography was performed, and mice were sacrificed at 28 days after stroke. Cardiomyocyte hypertrophy, myocardial capillary density, interstitial fibrosis, and inflammatory factor expression were measured in the heart. MicroRNA-126 expression and its target gene expression were measured in the heart. T2DM mice exhibit significant cardiac deficits such as decreased left ventricular ejection fraction (LVEF) and shortening fraction (LVSF), increased left ventricular diastolic dimension (LVDD), and reduced heart rate compared to non-DM mice. Stroke in non-DM and T2DM mice significantly decreases LVEF compared to non-DM and T2DM-sham, respectively. Cardiac dysfunction is worse in T2DM-stroke mice compared to non-DM-stroke mice. CD133+Exo treatment of T2DM-stroke mice significantly improves cardiac function identified by increased LVEF and decreased LVDD compared to PBS treated T2DM-stroke mice. In addition, CD133+Exo treatment significantly decreases body weight and blood glucose but does not decrease lesion volume in T2DM-stroke mice. CD133+Exo treatment of T2DM mice significantly decreases body weight and blood glucose but does not improve cardiac function. CD133+Exo treatment in T2DM-stroke mice significantly decreases myocardial cross-sectional area, interstitial fibrosis, transforming growth factor beta (TGF-β), numbers of M1 macrophages, and oxidative stress markers 4-HNE (4-hydroxynonenal) and NADPH oxidase 2 (NOX2) in heart tissue. CD133+Exo treatment increases myocardial capillary density in T2DM-stroke mice as well as upregulates endothelial cell capillary tube formation in vitro. MiR-126 is highly expressed in CD133+Exo compared to exosomes derived from endothelial cells. Compared to PBS treatment, CD133+Exo treatment significantly increases miR-126 expression in the heart and decreases its target gene expression such as Sprouty-related, EVH1 domain-containing protein 1 (Spred-1), vascular cell adhesion protein (VCAM), and monocyte chemoattractant protein 1 (MCP1) in the heart of T2DM-stroke mice. CD133+Exo treatment significantly improves cardiac function in T2DM-stroke mice. The cardio-protective effects of CD133+Exo in T2DM-stroke mice may be attributed at least in part to increasing miR-126 expression and decreasing its target protein expression in the heart, increased myocardial capillary density and decreased cardiac inflammatory factor expression.

Obesity and diabetes are jointly associated with functional disability in stroke survivors

BACKGROUND

Stroke is the most common cause of complex disability. Obesity and diabetes increase risk for functional disability in the general population, but their contribution to functional disability in stroke survivors is unknown.

OBJECTIVE

To investigate the joint association of obesity and diabetes with functional disability in stroke survivors.

METHODS

Cross-sectional data from 34,376 stroke survivors from the 2015 and 2017 Behavioral Risk Factor Surveillance System (BRFSS) surveys were examined. Weighted and age-adjusted prevalence estimates and adjusted odds ratios (AOR, adjusted for sociodemographic characteristics) with 95% confidence intervals (CIs) were calculated to compare prevalence and odds for self-reported functional disability, stratified by obesity-diabetes status (i.e., neither condition, obesity only, diabetes only, both conditions).

RESULTS

Prevalence of functional disability increased across obesity-diabetes categories in the total sample: neither condition (45.4%, 95% CI: 43.4%-47.4%), obesity only (55.3%, 95% CI: 52.7%-58.0%), diabetes only (60.8%, 95% CI: 57.5%-64.1%), and both conditions (70.3%, 95% CI: 67.7%-72.9%). Compared to respondents with neither condition, those with both obesity and diabetes had 2.62 (95% CI: 2.23-3.08) higher odds for functional disability; odds were also increased for respondents with obesity only (1.52, 95% CI: 1.32-1.76) and diabetes only (1.71, CI: 1.45-2.01).

CONCLUSIONS

Our findings indicated a joint effect of obesity and diabetes on functional disability that exceeded either condition alone, placing stroke survivors with both health conditions at greatest risk for diminished functional capacity. Recognizing obesity and diabetes as modifiable risk factors may be useful for identifying stroke sub-populations that could benefit from lifestyle intervention.

Diabetes Mellitus Impairs White Matter Repair and Long-Term Functional Deficits After Cerebral Ischemia

Background and Purpose- Type 2 diabetes mellitus (T2DM) is a major comorbidity that exacerbates ischemic brain injury and worsens functional outcome after stroke. T2DM is known to aggravate white matter (WM) impairment, but the underlying mechanism is not completely understood. This study was designed to test the hypothesis that T2DM impedes poststroke WM recovery by suppressing both oligodendrogenesis and beneficial microglia/macrophage responses. Methods- Permanent distal middle cerebral artery occlusion was performed in wild-type, homozygous diabetic db/db, and heterozygous db/+ mice. The adhesive removal, open field, and Morris water maze tests were used to assess neurobehavioral outcomes. Neuronal tissue loss, WM damage, oligodendrogenesis, and microglia/macrophage responses were evaluated up to 35 days after stroke. The functional integrity of WM was measured by electrophysiology. Primary microglia-oligodendrocyte cocultures were used for additional mechanistic studies. Results- T2DM exacerbated structural damage and impaired conduction of compound action potentials in WM 35 days after stroke. The deterioration in WM integrity correlated with poor sensorimotor performance. Furthermore, T2DM impaired the proliferation of oligodendrocyte precursor cells and the generation of new myelinating oligodendrocytes. T2DM also promoted a shift of microglia/macrophage phenotype toward the proinflammatory modality. Coculture studies confirmed that microglia/macrophage polarization toward the proinflammatory phenotype under high glucose conditions suppressed oligodendrocyte precursor cell differentiation. Conclusions- Deterioration of WM integrity and impairments in oligodendrogenesis after stroke are associated with poor long-term functional outcomes in experimental diabetes mellitus. High glucose concentrations may shift microglia/macrophage polarization toward a proinflammatory phenotype, significantly impairing oligodendrocyte precursor cell differentiation and WM repair.

Factors Associated With In-Hospital Mortality in Very Elderly Patients With Ischemic Stroke: A Cohort Study

INTRODUCTION

The highest mortality rates associated with ischemic stroke occur in patients of advanced age. However, studies of factors that establish the increase in hospital mortality are scanty in this population.

MATERIAL AND METHODS

Epidemiologic, clinical and laboratory data, etiology and ischemic stroke subtype and complications during hospitalization were analyzed in 195 patients aged 80 years or older. In attempt to associate prognostic factor with the in-hospital mortality during first 28 days from admission, the death and survivor groups were compared.

RESULTS

Among the 195 patients evaluated, the age was 85.3 ± 4.6 years with a mortality of 26.1%. Following the multivariate model, the factors associated with in-hospital mortality were: age (OR = 1.07, 95% CI = 1.00-1.20), the score less than or equal to 8 on Glasgow coma scale (OR = 22.87, 95% CI = 3.55-148.76), diabetes mellitus (OR = 3.40, 95% CI = 1.30-8.87), total anterior clinical subtype (OR = 5.15, 95% CI = 1.82-14.52) and infectious complications (OR = 8.38, 95% CI = 3.28-21.43).

CONCLUSIONS

The following risk factors were associated with a higher in-hospital mortality rate in patients over 79 years of age with ischemic stroke: older age, Glasgow coma score less than or equal to 8, total anterior circulation infarction, infection, and diabetes mellitus.

Incretin-Based Antihyperglycemic Agents for the Management of Acute Ischemic Stroke in Patients with Diabetes Mellitus: A Review

Diabetes mellitus (DM) is a major risk factor for ischemic stroke. Moreover, patients with DM suffer more severe strokes and have worse functional outcome following an acute stroke than patients without DM. In this context, data from animal studies and emerging evidence from clinical studies suggest that incretin-based antihyperglycemic agents might exert beneficial effects in patients with DM who suffer ischemic stroke. It appears that these agents exert neuroprotective actions that might both reduce infarct size and promote recovery. The present review summarizes the evidence on the potential role of incretin-based antihyperglycemic agents in the management of acute ischemic stroke.

Association of PAI-1 4G/5G Polymorphism with Ischemic Stroke in Chinese Patients with Type 2 Diabetes Mellitus

BACKGROUND/AIM

To investigate the association of the genetic polymorphisms of the plasminogen activator inhibitor type 1 (PAI-1) gene with the risk of ischemic stroke (IS) in subjects with type 2 diabetes mellitus (T2DM).

MATERIALS AND METHODS

Using a case-control study design, 175 individuals with T2D and IS were enrolled in the case group and 125 patients with T2D without IS were enrolled as controls. The clinical characteristics of the groups were compared, and genotypes were determined by direct DNA sequencing.

RESULTS

Male and hypertensive subjects were higher in the IS group (p = 0.002 and 0.014, respectively). High-density lipoprotein (HDL) and apolipoprotein A1 (APOA1) were lower in the IS group (p = 0.011 and 0.025, respectively); hemoglobin A1c (HbA1c), total homocysteine (tHcy), and FT4 levels were higher in the IS group (p = 0.022, 0.003, and 0.008, respectively). The 4G/4G, 4G/5G, and 5G/5G genotype frequencies were 40.0%, 46.4%, and 13.6% in the control group versus 31.4%, 52.0% and 16.6% in the IS group, respectively. Hypertension (odds ratio [OR] = 1.953, p = 0.020), tHcy (OR = 1.059, p = 0.029), thyroid-stimulating hormone (OR = 0.876, p = 0.039), and the PAI-1 genotype dominant allele model (OR = 1.748, p = 0.047) were associated with IS by multivariate analysis.

CONCLUSION

The PAI-1 genotype dominant allele model was a risk factor for IS in patients with T2DM of Jinan, China.

Determining the joint effect of obesity and diabetes on functional disability at 3-months and on all-cause mortality at 1-year following an ischemic stroke

BACKGROUND

Obesity and diabetes mellitus, or diabetes, are independently associated with post-ischemic stroke outcomes (e.g., functional disability and all-cause mortality). Although obesity and diabetes are also associated with post-ischemic stroke outcomes, the joint effect of obesity and diabetes on these post-ischemic stroke outcomes has not been explored previously. The purpose of the current study was to explore whether the effect of obesity on post-ischemic stroke outcomes differed by diabetes status in a cohort of acute ischemic stroke subjects with at least a moderate stroke severity.

METHODS

Data from the Interventional Management of Stroke (IMS) III clinical trial was analyzed for this post-hoc analysis. A total of 656 subjects were enrolled in IMS III and were followed for one year. The joint effects of obesity and diabetes on functional disability at 3-months and all-cause mortality at 1-year were examined.

RESULTS

Of 645 subjects with complete obesity and diabetes information, few were obese (25.74%) or had diabetes (22.64%). Obese subjects with diabetes and non-obese subjects without diabetes had similar odds of functional disability at 3-months following an ischemic stroke (adjusted common odds ratio, 1.038, 95% CI: 0.631, 1.706). For all-cause mortality at 1-year following an ischemic stroke, obese subjects with diabetes had a similar hazard compared with non-obese subjects without diabetes (adjusted hazard ratio, 1.005, 95% CI: 0.559, 1.808). There was insufficient evidence to declare a joint effect between obesity and diabetes on either the multiplicative scale or the additive scale for both outcomes.

CONCLUSIONS

In this post-hoc analysis of data from the IMS III clinical trial of acute ischemic stroke patients with at least a moderate stroke severity, there was not sufficient evidence to determine that the effect of obesity differed by diabetes status on post-ischemic stroke outcomes. Additionally, there was not sufficient evidence to determine that either factor was independently associated with all-cause mortality. Future studies could differentiate between metabolically healthy and metabolically unhealthy patients within BMI categories to determine if the effect of obesity on post-stroke outcomes differs by diabetes status.

Vitamin D deficiency in relation to the poor functional outcomes in nondiabetic patients with ischemic stroke

To assess the hypothesis that vitamin D, reflected by 25-hydroxyvitamin D (25(OH) D) would be associated with higher risk of poor functional outcomes amongst nondiabetic stroke patients. The present study was conducted in Nanchang, China. Serum concentration of 25(OH) D and National Institutes of Health Stroke Scale (NIHSS) were measured at the time of admission. Functional outcome was measured by modified Rankin scale (mRS) at 1 year after admission. Multivariate analyses were performed using logistic regression models. The cut point of 25(OH) D level for vitamin D deficiency was 20 ng/ml. In the present study, 266 nondiabetic subjects with stroke were included; 149 out of the 266 patients were defined as vitamin D deficiency (56%). The poor outcome distribution across the 25(OH) D quartiles ranged between 64% (first quartile) and 13% (fourth quartile). In those 149 patients with vitamin D deficiency, 75 patients were defined as poor functional outcomes, giving a prevalence rate of 50% (95% confidence interval (CI): 42–58%). In multivariate analysis models, for vitamin D deficiency, the adjusted risk of poor functional outcomes and mortality increased by 220% (odds ratio (OR): 3.2; 95% CI: 1.7–4.2, P<0.001) and 290% (OR: 3.9; 95% CI: 2.1–5.8, P<0.001), respectively. Vitamin D deficiency is associated with an increased risk of poor functional outcome events in Chinese nondiabetic stroke individuals.

Association of dialysis with in-hospital disability progression and mortality in community-onset stroke

AIM

End-stage renal disease is associated with increased risk of cerebrovascular disease, but the effect on post-stroke clinical outcomes has not been thoroughly investigated.

METHODS

Using the Japanese Diagnosis Procedure Combination database, which includes administrative claims and discharge abstract data, we examined the association between risk factors including dialysis therapy and in-hospital disability progression or mortality in patients with community-onset stroke. We extracted data of patients aged ≥ 20 years old who were admitted to the hospital within 3 days after onset of stroke between July 2010 and March 2013. The disability level was divided into modified Rankin Scale (mRS) 0-1, 2-3, 4-5, and 6 (death). Disability progression was defined as an increase in disability level. Odds ratios for in-hospital disability progression and mortality were calculated using logistic regression models.

RESULTS

Of 435 403 patients, 7562 (1.7%) received dialysis therapy. The median length of stay was 21 and 20 days for patients with and without dialysis, respectively. During the hospital stay, disability progressed in 100 402 (23.1%) patients and 45 919 (10.5%) died. Patients on dialysis had a higher prevalence of disability progression (26.8%) and mortality (13.1%) compared to those without dialysis (23.0% and 10.5%, respectively). Dialysis was associated with an increased risk of in-hospital disability progression (odds ratio, 1.56; 95% confidence interval, 1.47-1.66) and mortality (odds ratio 1.70; 95% confidence interval, 1.57-1.84). These risks were comparable among subtypes of stroke.

CONCLUSIONS

Dialysis was associated with an increased risk of in-hospital disability progression and mortality among patients with community-onset stroke, regardless of stroke subtype.

Serum lipoprotein and RBC rigidity index to predict cerebral infarction in patients with carotid artery stenosis

OBJECTIVE

This study aims to determine the risk factors and to predict the occurrence of cerebral infarction in patients with carotid artery stenosis.

METHODS

Two hundred and one subjects with carotid artery stenosis were retrospectively selected from Jinshan Branch of Shanghai Sixth People's Hospital, 115 cases of which with cerebral infarction and 86 without it. Clinical tests were performed including coagulation indices, fasting glucose, serum lipid, and blood rheology. Logistic regression analyses were used to identify the risk factors. Regression model was established, and receiver operating characteristic (ROC) curve was applied to analyze its diagnostic value.

RESULTS

Our data indicated that apolipoprotein AI (OR = 0.051, 95% CI: 0.009-0.295), lipoprotein (a) (OR = 1.003, 95% CI: 1.001-1.005), and RBC rigidity index (OR = 0.383, 95% CI: 0.209-0.702) were independent risk factors. Area under the curve (AUC) of the regression model = 0.78, with the sensitivity of 73.9% (95% CI: 64.9%-81.7%) and specificity of 69.2% (95% CI: 52.4%-83.0%). Prediction probability was determined while logistic regression score >0.748 defaulted as high-risk status. High-risk ratios were 80% in progressive cerebral infarction and 72% in nonprogressive cerebral infarction (P > .05), respectively, while significant differences were found when both compared with controls (P < .001).

CONCLUSIONS

We show herein that the regression model based on apolipoprotein AI, lipoprotein (a), and RBC IR is a promising tool to predict the occurrence of cerebral infarction in patients with carotid artery stenosis. However, identification of novel diagnostic markers for progressive cerebral infarction is still necessary.

Association between carotid plaque characteristics and acute cerebral infarction determined by MRI in patients with type 2 diabetes mellitus

BACKGROUND

Type 2 diabetes mellitus (T2DM) might aggravate the carotid plaque vulnerability, and increase the risk for ischemic stroke. Few studies reported the acute stroke subtype with carotid plaque characteristics in T2DM patients. This study aimed to investigate the association between carotid plaque characteristics and acute cerebral infarct (ACI) lesion features determined by MRI in T2DM patients.

METHODS

Patients with acute cerebrovascular syndrome in internal carotid artery territory were recruited. All patients were stratified into T2DM and non-T2DM groups and underwent both carotid and brain MRI scans. Ipsilateral carotid plaque morphological and compositional characteristics, intracranial and extracranial carotid artery stenosis were also determined. Stroke subtype based on the Trial of ORG 10172 in Acute Stroke Treatment classification and ACI lesion patterns were evaluated.

RESULTS

Of the recruited 140 patients, 68 (48.6%) patients had T2DM (mean age 64.16 ± 11.38 years, 40 males). T2DM patients exhibited higher prevalence of carotid type IV-VI lesions, larger plaque burden as well as larger lipid-rich necrotic core (LRNC) compared with non-T2DM patients. Among the patients with carotid LRNC on symptomatic side, more concomitant large perforating artery infarct patterns and larger ACI size in the internal carotid artery territory were found in T2DM group than those in non-T2DM group. Carotid plaque with LRNC% > 22.0% was identified as an independent risk factor for the presence of ACI lesions confined to the carotid territory in T2DM patients, regardless of other risk factors.

CONCLUSIONS

This study shows that more concomitant large perforating artery infarct patterns and larger ACI size in the internal carotid artery territory were found in the T2DM patients with ipsilateral carotid LRNC plaque than those in non-T2DM patients. Quantification of the carotid plaque characteristics, particularly the LRNC% by MRI has the potential usefulness for stroke risk stratification.

Effects of glucose-lowering agents on ischemic stroke

Diabetes mellitus (DM) is a major risk factor for cardiovascular events, including ischemic stroke. Moreover, ischemic stroke appears to be more severe in these patients and to be associated with less favorable outcomes. However, strict glycemic control does not appear to reduce the risk of ischemic stroke. On the other hand, newer glucose-lowering agents (glucagon-like peptide 1 receptor agonists and sodium-glucose cotransporter 2 inhibitors) reduced the risk of cardiovascular events in recent randomized, placebo-controlled trials. Semaglutide also reduced the risk of ischemic stroke. These benefits are independent of glucose lowering and might be due to the favorable effects of these agents on body weight and blood pressure. Pioglitazone also reduced the risk of recurrent stroke in patients with insulin resistance or type 2 DM but the unfavorable safety profile limits its use. In contrast, sulfonylureas and dipeptidyl peptidase 4 inhibitors have a neutral effect on cardiovascular morbidity and might be less attractive options in this high-risk population.

Vascular Complications of Diabetes

Over the last several decades, the global incidence and prevalence of diabetes mellitus has increased significantly. The raised incidence rate is projected to continue as greater numbers of persons adopt a Western lifestyle and diet. Patients with diabetes mellitus are at heightened risk of both adverse microvascular and cardiovascular events. Moreover, once cardiovascular disease develops, diabetes mellitus exacerbates progression and worsens outcomes. The medical management of patients with diabetes mellitus mandates comprehensive risk factor modification and antiplatelet therapy. Recent clinical trials of new medical therapies continue to inform the care of patients with diabetes mellitus to reduce both cardiovascular morbidity and mortality.

Hyperglycemia and diabetes have different impacts on outcome of ischemic and hemorrhagic stroke

INTRODUCTION

Stroke is the second leading cause of long-term disability and death worldwide. Diabetes and hyperglycemia may impact the outcome of stroke. We examined the impact of hyperglycemia and diabetes on in-hospital death among ischemic and hemorrhagic stroke patients.

MATERIAL AND METHODS

Data from 766 consecutive patients with ischemic (83.15%) and hemorrhagic stroke were analyzed. Patients were classified into four groups: ischemic and diabetic; ischemic and non-diabetic; hemorrhagic and diabetic; and hemorrhagic and non-diabetic. Serum glucose was measured on admission at the emergency department together with biochemical and clinical parameters.

RESULTS

Mean admission glucose in ischemic stroke patients with diabetes was higher than in non-diabetic ones (p < 0.001) and in hemorrhagic stroke patients with diabetes than in those without diabetes (p < 0.05). Mean admission glucose in all patients who died was significantly higher than in patients who survived. In multivariate analysis, the risk factors for outcome in patients with ischemic stroke and without diabetes were age, admission glucose level and estimated glomerular filtration rate (eGFR), while in diabetics they were female gender, admission glucose level, and eGFR; in patients with hemorrhagic stroke and without diabetes they were age and admission glucose levels. The cut-off value in predicting death in patients with ischemic stroke and without diabetes was above 113.5 mg/dl, while in diabetics it was above 210.5 mg/dl.

CONCLUSIONS

Hyperglycemia on admission is associated with worsened clinical outcome and increased risk of in-hospital death in ischemic and hemorrhagic stroke patients. Diabetes increased the risk of in-hospital death in hemorrhagic stroke patients, but not in ischemic ones.

Stress hyperglycemia and acute ischemic stroke in-hospital outcome

BACKGROUND AND AIMS

Stress hyperglycemia is frequent in patients with acute ischemic stroke. However, it is unclear whether stress hyperglycemia only reflects stroke severity or if it is directly associated with adverse outcome. We aimed to evaluate the prognostic significance of stress hyperglycemia in acute ischemic stroke.

METHODS

We prospectively studied 790 consecutive patients who were admitted with acute ischemic stroke (41.0% males, age 79.4±6.8years). The severity of stroke was assessed at admission with the National Institutes of Health Stroke Scale (NIHSS). Stress hyperglycemia was defined as fasting serum glucose levels at the second day after admission ≥126mg/dl in patients without type 2 diabetes mellitus (T2DM). The outcome was assessed with adverse outcome rates at discharge (modified Rankin scale between 2 and 6) and with in-hospital mortality.

RESULTS

In the total study population, 8.6% had stress hyperglycemia. Patients with stress hyperglycemia had more severe stroke. Independent predictors of adverse outcome at discharge were age, prior ischemic stroke and NIHSS at admission whereas treatment with statins prior to stroke was associated with favorable outcome. When the NIHSS was removed from the multivariate model, independent predictors of adverse outcome were age, heart rate at admission, prior ischemic stroke, log-triglyceride (TG) levels and stress hyperglycemia, whereas treatment with statins prior to stroke was associated with favorable outcome. Independent predictors of in-hospital mortality were atrial fibrillation (AF), diastolic blood pressure (DBP), serum log-TG levels and NIHSS at admission. When the NIHSS was removed from the multivariate model, independent predictors of in-hospital mortality were age, AF, DBP, log-TG levels and stress hyperglycemia.

CONCLUSION

Stress hyperglycemia does not appear to be directly associated with the outcome of acute ischemic stroke. However, given that patients with stress hyperglycemia had higher prevalence of cardiovascular risk factors than patients with normoglycemia and that glucose tolerance was not evaluated, more studies are needed to validate our findings.

Higher Serum Uric Acid May Contribute to Cerebral Infarction in Patients with Type 2 Diabetes Mellitus: a Meta-Analysis

Higher levels of serum uric acid tend to increase the diabetes-related complications. We performed a meta-analysis to investigate whether the higher serum uric acid levels were associated with cerebral infarction in type 2 diabetes patients. We searched for relevant studies in the PubMed, Embase, China National Knowledge Infrastructure, China BioMedicine, and VIP database until August 2015. All observational studies comparing serum uric acid levels in type 2 diabetic patients with and without cerebral infarction were included. We calculated the ratio of means (RoM) of serum uric acid by mean _{cerebral infarction}/mean _{diabetic control} from the individual studies and then pooled RoM and its 95 % confidence intervals (CI). A total of 23 eligible studies were identified. Pooled estimates indicated that type 2 diabetes patients with cerebral infarction were associated with 29 % (RoM 1.29; 95 % CI 1.26-1.31) higher serum uric acid levels than those without cerebral infarction in a random effect model. Subgroup analyses based on gender indicated that RoM was 1.23 (95 % CI 1.09-1.38) for men and 1.12 (95 % CI 0.98-1.27) for women. This meta-analysis suggests that higher serum uric acid levels may contribute to cerebral infarction in patients with type 2 diabetes.

Chromium supplementation improved post-stroke brain infarction and hyperglycemia

Hyperglycemia is common after acute stroke and is associated with a worse outcome of stroke. Thus, a better understanding of stress hyperglycemia is helpful to the prevention and therapeutic treatment of stroke. Chromium is an essential nutrient required for optimal insulin activity and normal carbohydrate and lipid metabolism. Beyond its nutritional effects, dietary supplement of chromium causes beneficial outcomes against several diseases, in particular diabetes-associated complications. In this study, we investigated whether post-stroke hyperglycemia involved chromium dynamic mobilization in a rat model of permanent focal cerebral ischemia and whether dietary supplement of chromium improved post-stroke injury and alterations. Stroke rats developed brain infarction, hyperglycemia, hyperinsulinemia, glucose intolerance, and insulin resistance. Post-stroke hyperglycemia was accompanied by elevated secretion of counter-regulatory hormones including glucagon, corticosterone, and norepinephrine, decreased insulin signaling in skeletal muscles, and increased hepatic gluconeogenesis. Correlation studies revealed that counter-regulatory hormone secretion showed a positive correlation with chromium loss and blood glucose increased together with chromium loss. Daily chromium supplementation increased tissue chromium levels, attenuated brain infarction, improved hyperglycemia, and decreased plasma levels of glucagon and corticosterone in stroke rats. Our findings suggest that stroke rats show disturbance of tissue chromium homeostasis with a net loss through urinary excretion and chromium mobilization and loss might be an alternative mechanism responsible for post-stroke hyperglycemia.

The Influence of Acute Hyperglycemia in an Animal Model of Lacunar Stroke That Is Induced by Artificial Particle Embolization

Animal and clinical studies have revealed that hyperglycemia during ischemic stroke increases the stroke's severity and the infarct size in clinical and animal studies. However, no conclusive evidence demonstrates that acute hyperglycemia worsens post-stroke outcomes and increases infarct size in lacunar stroke. In this study, we developed a rat model of lacunar stroke that was induced via the injection of artificial embolic particles during full consciousness. We then used this model to compare the acute influence of hyperglycemia in lacunar stroke and diffuse infarction, by evaluating neurologic behavior and the rate, size, and location of the infarction. The time course of the neurologic deficits was clearly recorded from immediately after induction to 24 h post-stroke in both types of stroke. We found that acute hyperglycemia aggravated the neurologic deficit in diffuse infarction at 24 h after stroke, and also aggravated the cerebral infarct. Furthermore, the infarct volumes of the basal ganglion, thalamus, hippocampus, and cerebellum but not the cortex were positively correlated with serum glucose levels. In contrast, acute hyperglycemia reduced the infarct volume and neurologic symptoms in lacunar stroke within 4 min after stroke induction, and this effect persisted for up to 24 h post-stroke. In conclusion, acute hyperglycemia aggravated the neurologic outcomes in diffuse infarction, although it significantly reduced the size of the cerebral infarct and improved the neurologic deficits in lacunar stroke.

Long-Term Mortality and Its Risk Factors in Stroke Survivors

BACKGROUND

Stroke is one of the leading causes of mortality worldwide. Understanding the risk factors associated with stroke mortality is important to improve patient management. Few studies have examined long-term mortality and its associated predictive risk factors.

METHODS

We examined long-term mortality in 1137 patients with acute stroke and compared it to a geographically age- and sex-matched, stroke-free control group. We followed the stroke patients for as long as 16.4 years. In 1018 of these patients we assessed the effect of demographic, clinical, and hematological factors on mortality.

RESULTS

At the end of the study period, 51.7% of the patients and 32.7% of the stroke-free control individuals had died (hazard ratio 2.2, confidence interval 1.9-2.5, P < .001). A total of 72.5% of the patients and 53% of the controls with 12 years' follow-up (n = 570) had died (P < .001). Regression analyses indicate that, in addition to known risk factors such as age, diabetes, and stroke severity, both low cholesterol (P < .001) and hemoglobin (P < .002), hyperhomocysteinemia (P = .005), and elevated serum creatinine (P < .001) at index stroke are associated with increased long-term mortality.

CONCLUSIONS

Stroke patients surviving the first year after stroke have a markedly increased mortality rate as seen in long-term follow-up. Furthermore, the results from this study indicate that changes in creatinine, homocysteine, and hemoglobin should be followed more carefully as standard practice after acute stroke.

Vascular Risk Factors in Patients with Different Subtypes of Ischemic Stroke May Affect Their Outcome after Intravenous tPA

Intravenous (IV) tissue-type plasminogen activator (tPA) is the only approved noninvasive therapy for acute ischemic stroke (AIS). However, after tPA treatment, the outcome of patients with different subtypes of stroke according to their vascular risk factors remains to be elucidated. We aim to explore the relationship between the outcome and different risk factors in patients with different subtype of acute strokes treated with IV tPA. Records of patients in this cohort were reviewed. Data collected and analysed included the demographics, vascular risk factors, baseline National Institutes of Health Stroke Scale (NIHSS) scores, 90-day modified Rankin Scores (mRS), and subtypes of stroke. By using the 90-day mRS, patients were dichotomized into favorable versus unfavorable outcome in each subtype of stroke. We identified the vascular risk factors that are likely associated with the poor outcome in each subtype. Among 570 AIS patients received IV tPA, 217 were in the large artery atherosclerosis (LAA) group, 146 in the small vessel occlusion(SVO) group, and 140 in the cardioaortic embolism(CE) group. Lower NIHSS score on admission was related to favorable outcome in patients in all subtypes. Patients with history of dyslipidemia were likely on statin treatment before their admission and hence less likely to have elevated cholesterol level on admission. Therefore, there was a possible paradoxical effect on the outcome in patients with LAA and SVO subtypes of strokes. SVO patients with history of diabetes had higher risk of unfavorable outcome. SVO patients had favorable outcome if their time from onset to treatment was short. In conclusion, the outcome of patients treated with IV tPA may be related to different vascular risk factors associated with different subtypes of stroke.