Baseline diabetic status and admission blood glucose were poor prognostic factors in the EPITHET trial

Functional long-term outcome following endovascular thrombectomy in patients with acute ischemic stroke

Endovascular thrombectomy (EVT) is the most effective treatment for acute ischemic stroke caused by large vessel occlusion (LVO). Yet, long-term outcome (LTO) and health-related quality of life (HRQoL) in these patients have rarely been addressed, as opposed to modified Rankin scale (mRS) recordings. We analysed demographic data, treatment and neuroimaging parameters in 694 consecutive stroke patients in a maximum care hospital. In 138 of these patients with respect on receipt of written informed consent, LTO and HRQoL were collected over a period of 48 months after EVT using a standardised telephone survey (median 2.1 years after EVT). Age < 70 years (OR 4.82), lower NIHSS on admission (OR 1.11), NIHSS ≤ 10 after 24 h (OR 11.23) and complete recanalisation (mTICI3) (OR 7.79) were identified as independent predictors of favourable LTO. Occurrence of an infection requiring treatment within the first 72 h was recognised as a negative predictor for good long-term outcome (OR 0.22). Patients with mRS > 2 according to the telephone survey more often had complaints regarding mobility, self-care, and usual activity domains of the HRQoL. Our results underline a sustainable positive effect of effective EVT on the quality of life in LVO stroke. Additionally, predictive parameters of outcome were identified, that may support clinical decision making in LVO stroke.

Treatment with intravenous alteplase in ischaemic stroke patients with onset time between 4.5 and 24 hours (HOPE): protocol for a randomised, controlled, multicentre study

BACKGROUND

While intravenous thrombolysis is recommended for patients who had an acute ischaemic stroke (AIS) within 4.5 hours of symptom onset, there are few randomised trials investigating the benefits of thrombolysis beyond this therapeutic window.

AIM

To determine whether patients who had an AIS selected with the presence of potentially salvageable tissue on CT perfusion at 4.5-24 hours after stroke onset (for stroke with unknown onset time, the midpoint of the time last known to be well and symptom recognition time; for wake-up stroke, the midpoint of the time last known to be well or sleep onset and wake up time) will benefit from intravenous thrombolysis.

DESIGN

HOPE is a prospective, multicentre, randomised, open-label blinded endpoint trial with the stage of phase III. The treatment allocation employs 1:1 randomisation. The treatment arm under investigation is alteplase with standard therapy, the control arm is standard therapy. Eligibility imaging criteria include ischaemic core volume ≤70 mL, penumbra ≥10 mL and mismatch ≥20%.

STUDY OUTCOMES

The primary outcome is non-disabled functional outcome (assessed as modified Rankin Scale score of 0-1 at 90 days).

DISCUSSION

HOPE is the first trial to investigate whether intravenous thrombolysis with alteplase offers benefits in patients who had an AIS presenting within 4.5-24 hours, which has the potential to extend time window and expand eligible population for thrombolysis therapy.

Blood glucose level affects prognosis of patients who received intravenous thrombolysis after acute ischemic stroke? A meta-analysis

Background and objectives

Intravenous recombinant tissue plasminogen activator (rtPA) thrombolysis is an effective treatment for acute ischemic stroke. Hyperglycemia is a major risk factor for the occurrence, development, and prognosis of ischemic stroke. This meta-analysis purposefully estimates the association between hyperglycemia and poor prognosis in acute ischemic stroke patients receiving intravenous rtPA thrombolytic therapy.

Materials and methods

According to the predefined inclusion criteria, we searched PubMed, Web of Science, and Cochrane Library databases. The association of high blood glucose(>140mg/dl) with symptomatic intracranial hemorrhage (sICH), poor clinical outcome and mortality at 90 days post-rtPA thrombolysis was studied using both a common effects model and a random effects model. Odds ratios (ORs) were plotted on forest plots.

Results

Of a total cohort of 2565 patients who received intravenous thrombolytic therapy, 721 had higher blood glucose. High glucose level significantly increased the odds of sICH (OR 1.80; 95% confidence interval(95%CI): 1.30- 2.50) and poor clinical outcome at 90 days (OR 1.82; 95%CI: 1.52-2.19), and all-cause mortality at 90 days (OR 2.51; 95%CI:1.65-3.82).

Conclusions

In our meta-analysis, high blood glucose was significantly associated with sICH, poor clinical outcome and higher mortality at 90 days.

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

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

Prognosis and Predictors of Symptomatic Intracranial Hemorrhage After Endovascular Treatment of Large Vessel Occlusion Stroke

Background

Symptomatic intracranial hemorrhage (sICH) is a devastating complication of endovascular treatment (EVT) in patients with acute ischemic stroke (AIS) and is associated with high risk of disability and mortality. This study intended to evaluate the predictors of sICH after EVT in patients with large vessel occlusion (LVO)-induced AIS.

Methods

We conducted a retrospective review on consecutive AIS patients who underwent EVT in our University hospital between January 2019 and August 2020. The patients were classified into two groups based upon the occurrence of sICH. The main outcomes were the occurrence of sICH using the Heidelberg Bleeding Classification and functional condition at 90 days. Multivariate logistic regression analysis and receiver operating characteristics (ROC) curves were used to identify independent predictors of sICH after EVT.

Results

Three hundred and 69 patients were enrolled in the study, of which 16.8% (n = 62) developed sICH. Favorable neurological outcome was lower in patients with sICH than in patients without sICH (6.5 vs. 43.3%; P < 0.001), with the overall mortality being 112 (30.4%) at 90 days post- EVT. Results from univariate analysis showed significant differences between the two groups in the prevalence of diabetes, initial Alberta Stroke Program Early CT Score (ASPECTS) score, National Institutes of Health Stroke Scale (NIHSS) score after operation, the levels of fasting blood glucose (FBG), neutrophil to lymphocyte ratio (NLR), platelets (PLT), and thrombin time (TT) at admission. Multivariate logistic regression analysis showed that FBG ≥ 7.54 mmol/L (OR: 2.765; 95% confidence interval [CI]: 1.513–5.054), NLR ≥ 5.48 (OR: 2.711; 95% CI: 1.433–5.128), TT at admission ≥ 16.25 s (OR: 2.022; 95% CI: 1.115–3.667), and NIHSS score within 24 h after the operation ≥ 10 (OR: 3.728; 95% CI: 1.516–9.170) were independent predictors of sICH. The combination of NLR ≥ 5.48, FBG ≥ 7.54 mmol/L, TT at admission ≥ 16.25 s, and NIHSS score within 24 h after the operation ≥ 10 generated an optimal prediction model (AUC: 0.723).

Conclusion

Higher levels of FDG, NLR, TT at admission, and NIHSS score after operation were associated with sICH after EVT in patients with LVO-induced AIS.

Fasting Blood-Glucose Level and Clinical Outcome in Anterior Circulation Ischemic Stroke of Different Age Groups After Endovascular Treatment

OBJECTIVE

We aimed to analyze the association between fasting blood-glucose (FBG) level and 3-month functional outcome in anterior circulation ischemic stroke in different age groups after endovascular treatment (EVT).

METHODS

We retrospectively analyzed the consecutive patients with acute ischemic stroke (AIS) receiving EVT from our department between July 2015 and March 2021. The patients were categorized into the older (≥60 years) and younger (<60 years) groups, and patients in each age group were dichotomized into favorable versus unfavorable outcomes according to the 3-month modified Rankin Scale (mRS) score.

RESULTS

A total of 504 patients (286 males and 218 females) were included in our study. Three hundred ninety-two patients (77.8%) belonged to the group aged ≥60 years, and 112 (22.2%) belonged to the group aged <60 years. At the end of the study, 222 (56.6%) patients developed unfavorable outcomes in the older group and 31 (27.7%) showed unfavorable outcomes in the younger group. FBG level of the younger patients was significantly lower than that of older patients. In the older group, FBG level independently predicted a 3-month clinical unfavorable outcome with an odds ratio of 1.242 (95% confidence interval, 1.096-1.407; p = 0.001). However, the association was not found in the younger group (p = 0.376).

CONCLUSION

Higher FBG level is an independent risk factor for 3-month unfavorable outcome in the AIS patients aged ≥60 years receiving EVT, but no similar effect was seen in the group aged <60 years.

Adiponectin-Transfected Endothelial Progenitor Cells Have Protective Effects After 2-Hour Middle-Cerebral Artery Occlusion in Rats With Type 2 Diabetes Mellitus

Objectives: This present study aimed to examine the effects of adiponectin-transfected endothelial progenitor cells (LV-APN-EPCs) on cerebral ischemia–reperfusion injury in rats with type 2 diabetes mellitus (T2DM) and to explore the underlying mechanisms.

Methods: Seventy male Sprague–Dawley rats with T2DM were randomly divided into sham, phosphate-buffered saline (PBS), LV-APN-EPCs, LV-EPCs, and EPCs groups. Transient middle cerebral artery occlusion (MCAO) was induced by the intraluminal suture method. After 1 h of reperfusion, the five interventions were performed by tail-vein injections. The modified neurological severity score (mNSS) was used to assess neurological function before and on days 1, 7, and 14 after MCAO. After 14 days, magnetic resonance imaging scanning, hematoxylin and eosin staining, terminal dUTP nick-end labeling staining, Western blotting analysis, cluster of differentiation (CD) 31 immunofluorescence, and enzyme-linked immunosorbent assay were used to evaluate infarct rate, morphological damage, cell apoptosis, and microvessel density.

Results: Compared with PBS, LV-EPCs, and EPCs groups, the LV-APN-EPCs group showed significantly lower mNSS score, lower infarct rate, and less morphological damage (all P < 0.05). In addition, compared with other groups, the LV-APN-EPCs group had significantly increased levels of B cell lymphoma/leukemia-2 (Bcl-2) protein, CD31+ microvessels, endothelial nitric oxide synthase, and vascular endothelial growth factor, and decreased levels of Bcl-2-associated X protein and neuronal apoptosis in the peri-infarct cortex (all P < 0.05).

Conclusion: These results suggest that LV-APN-EPCs exert protective effects against cerebral ischemia–reperfusion injury in T2DM rats by increasing angiogenesis.

HbA1c (Glycated Hemoglobin) Levels and Clinical Outcome Post-Mechanical Thrombectomy in Patients With Large Vessel Occlusion

Background and Purpose- We analyzed the relationship between HbA1c (glycated hemoglobin) levels and clinical outcomes in patients with large vessel occlusion treated with mechanical thrombectomy (MT). Methods- A total of 534 patients with acute ischemic stroke (AIS) treated with MT were enrolled in this prospective cohort study. The primary outcome measured was the modified Rankin Scale score at 3 months, according to HbA1c level. High HbA1c levels were defined as a plasma level of HbA1c >6.5%. Favorable outcomes were defined as functional independence, with modified Rankin Scale scores of 0 to 2. Secondary functional outcomes included mortality, early clinical outcomes, and intracranial hemorrhage. Results- The number of patients with a favorable outcome was significantly lower in patients with HbA1c >6.5% than in those with HbA1c ≤6.5% (28.8% versus 42.1%; P=0.006). In multivariate analysis, high HbA1c levels (especially >7.0% HbA1c) were significantly associated with poor functional outcomes 3 months after AIS in patients with large vessel occlusion treated with MT. High HbA1c was also significantly associated with increased mortality and worse early clinical outcomes after AIS in patients treated with MT. Subgroup analyses showed that HbA1c >6.5% was associated with significantly lower odds of functional independence at 3 months after AIS, when comparing the recanalized group with nonrecanalized patients. Conclusions- These results suggest that high HbA1c level is an independent predictor of a poor outcome at 3 months after AIS in patients with large vessel occlusion treated with MT, particularly in those with recanalization, and may augment the risk of mortality and early clinical worsening after AIS.

The silver effect of admission glucose level on excellent outcome in thrombolysed stroke patients

Higher admission glucose levels (AGL) are associated with less favorable outcome in thrombolysis. But, could AGL’s impact on outcome vary by onset-to-treatment (OTT) time? Is hyperglycemia associated with a shorter therapeutic time window for excellent outcome for thrombolysed stroke patients? We assessed predictive values of AGL, baseline NIHSS, age, and OTT time quartiles on excellent outcome (3-month modified Rankin score of 0–1) in 773 patients treated by rt-Pa. We added the AGL × OTT time quartile interaction in the model and separately analyzed the predictive values of AGL, age, and NIHSS for each OTT time quartile if the interaction was significant. AGL, baseline NIHSS, age, and OTT time quartiles were significant predictors. When added in the model, the AGL × OTT interaction was significant (OR: 0.96, 95% CI: 0.94–0.99, p: 0.0009). AGL was predictive only during the third OTT time quartile (181–224 min). During this period, the predicted rate of excellent outcome was 16% for AGL = 6.5 mmol/L and 8% for AGL = 8 mmol/L. The rate of excellent outcome was not decreased in hyperglycemic patients for OTT time ≤ 180 min (20 vs. 24.5% p: 0.37), but was decreased for OTT time > 180 min (9.6 vs. 26.7% p: 0.00001). Similar results were found in patients with MCA recanalization, but not in patients without recanalization. The therapeutic time window for excellent outcome is shortened in hyperglycemic patients. This would support the design of “freezing penumbra” randomized trials based on ultra-early AGL control.

Impaired fasting glucose is associated with unfavorable outcome in ischemic stroke patients treated with intravenous alteplase

OBJECTIVES

Hyperglycemia on admission and diabetes mellitus type II are associated with unfavorable outcome in stroke patients. We studied whether impaired fasting glucose (IFG) is associated with unfavorable outcome in ischemic stroke patients treated with intravenous alteplase as well and if IFG is a stronger prognostic factor than hyperglycemia on admission.

METHODS

We studied 220 consecutive patients with ischemic stroke treated with intravenous alteplase. In all nondiabetic patients, fasting glucose was determined on day 2-5. IFG was defined as fasting glucose level of ≥ 5.6 mmol/L, hyperglycemia on admission as glucose levels ≥ 7.9 mmol/L. The primary effect measure was the adjusted common odds ratio (acOR) for a shift in the direction of worse outcome on the modified Rankin Scale at 3 months, estimated with ordinal logistic regression, and adjusted for common prognostic factors.

RESULTS

The fasting glucose levels were available in 194 and admission glucose levels in 215 patients. Sixty-three (32.5%) had IFG, 58 (27%) hyperglycemia on admission and 32 (14.6%) pre-existent diabetes. Patients with IFG showed a shift towards worse functional outcome compared with patients with normal fasting glucose levels (acOR 2.77; 95% CI 1.54-4.97), which was stronger than hyperglycemia on admission (acOR 1.75; 95% CI 0.91-3.4).

CONCLUSIONS

IFG is associated with unfavorable outcome after treatment with intravenous alteplase for acute ischemic stroke. IFG predicts unfavorable outcome better than hyperglycemia on admission.

Role of prediabetes in stroke

Stroke is one of the leading causes of death and probably the greatest cause of adult disability worldwide. Diabetes mellitus (DM) is a state of accelerated aging of blood vessels. Patients with diabetes have increased risk of stroke. Hyperglycemia represents a risk factor for poor outcome following stroke, and probably is just a marker of poor outcome rather than a cause. Lowering of blood glucose levels has not been shown to improve prognosis. Also, prevention of stroke risk among patients with DM is not improved with therapy for reduction of glucose levels. On the other hand, prediabetes, a metabolic state between normal glucose metabolism and diabetes, is a risk factor for the development of DM type 2 and subsequently for stroke. Several methods are known to identify prediabetes patients, including fasting plasma glucose levels, 2-hour post load glucose levels, and glycosylated hemoglobin levels. In this text, we tried to summarize known data about diagnosis, epidemiology, risk factors, pathophysiology, and prevention of prediabetes in relation to DM and stroke.

Increased admission and fasting glucose are associated with unfavorable short-term outcome after intra-arterial treatment of ischemic stroke in the MR CLEAN pretrial cohort

BACKGROUND

Limited data are available on the impact of fasting glucose on outcome after intra-arterial treatment (IAT). We studied whether hyperglycemia on admission and impaired fasting glucose (IFG) are associated with unfavorable outcome after IAT in acute ischemic stroke.

METHODS

Patients were derived from the pretrial registry of the MR CLEAN-trial. Hyperglycemia on admission was defined as glucose>7.8mmol/L, IFG as fasting glucose>5.5mmol/L in the first week of admission. Primary effect measure was the adjusted common odds ratio (acOR) for a shift in the direction of worse outcome on the modified Rankin Scale at discharge, estimated with ordinal logistic regression, adjusted for common prognostic factors.

RESULTS

Of the 335 patients in which glucose on admission was available, 86 (26%) were hyperglycemic, 148 of the 240 patients with available fasting glucose levels (62%) had IFG. Median admission glucose was 6.8mmol/L (IQR 6-8). Increased admission glucose (acOR 1.2, 95%CI 1.1-1.3), hyperglycemia on admission (acOR 2.6, 95%CI 1.5-4.6) and IFG (acOR 2.8, 95%CI 1.4-5.6) were associated with worse functional outcome at discharge.

CONCLUSION

Increased glucose on admission and IFG in the first week after stroke onset are associated with unfavorable short-term outcome after IAT of acute ischemic stroke.

Acute ischemic stroke patients with diabetes should not be excluded from intravenous thrombolysis

The benefit of intravenous thrombolysis (IVT) has been questioned for patients with diabetes mellitus (DM) in cases of acute ischemic stroke (IS). Our objective was to analyze the differences in outcome according to prior diagnosis of DM and the use or not of IVT. Observational study with inclusion of consecutive IS patients admitted to an stroke unit. Demographic data, vascular risk factors, comorbidity, stroke severity and 3-month follow-up outcome (modified Rankin Scale) were compared according to prior diagnosis of DM and the use or not of IVT. A total of 1,139 IS patients were admitted; 283 (24.8%) patients had a diagnosis of DM, and 261 were IVT treated (23.2% of the group without DM and 21.9% of the DM group). The IVT-treated patients with DM were older, had more comorbidities and had higher glucose levels on admission than those without DM and than IVT-treated patients. No significant differences in stroke severity, hemorrhagic transformation, in-hospital mortality or outcome at 3 months were found. The logistic regression analysis showed that stroke severity was associated with a higher risk of a poor outcome in IVT-treated patients, with no significant effect from DM after adjustment for confounders. Moreover, IVT was independently associated with a lower risk of poor outcome in DM patients (OR 0.49; 95% CI 0.31-0.76; P = .002). DM patients should not be excluded from IVT, because DM is not associated with a poor outcome after IVT and this treatment is clearly beneficial for DM patients as compared with DM patients not treated with IVT.

Unfavorable neurological outcome in diabetic patients with acute ischemic stroke is associated with incomplete recanalization after intravenous thrombolysis

Objective

To assess the impact of diabetes on neurological outcome and recanalization in acute ischemic stroke (AIS) after intravenous thrombolysis (IVT).

Methods

Clinical data of 419 consecutive patients with AIS who received IVT between June 2009 and April 2014. Based on the medical history and new diagnosis, the patients were divided into groups with and without diabetes. Neurological outcomes at 24 h, 7 days and 3 months after IVT were evaluated. Favorable outcome was defined as National Institutes of Health Stroke Scale (NIHSS) score decrease ≥4 points from baseline or 0 at 24 h, NIHSS decrease ≥8 points or 0 at day 7, or modified Rankin scale ≤1 at 3 months after IVT. Recanalization on non-invasive imaging was evaluated in patients with large vessel occlusion (LVO) according to thrombolysis in myocardial infarction grades.

Results

Among 419 patients, 98 (23.4%) had diabetes. Multivariable analyses showed that comorbidity of diabetes was an independent predictor of unfavorable outcome at 24 h (OR=0.534, 95% CI 0.316 to 0.903, p=0.019), at day 7 (OR=0.382, 95% CI 0.220 to 0.665, p=0.001), and at 3 months (OR=0.464, 95% CI 0.266 to 0.808, p=0.007). In patients with LVO, diabetes was an independent predictor of incomplete recanalization 24 h after IVT (OR=0.268, 95% CI 0.075 to 0.955, p=0.042).

Conclusions

Diabetic patients with AIS had unfavorable neurological outcome, potentially linked to incomplete recanalization after IVT.

NADPH oxidase-2: linking glucose, acidosis, and excitotoxicity in stroke

SIGNIFICANCE

Neuronal superoxide production contributes to cell death in both glutamate excitotoxicity and brain ischemia (stroke). NADPH oxidase-2 (NOX2) is the major source of neuronal superoxide production in these settings, and regulation of NOX2 activity can thereby influence outcome in stroke.

RECENT ADVANCES

Reduced NOX2 activity can rescue cells from oxidative stress and cell death that otherwise occur in excitotoxicity and ischemia. NOX2 activity is regulated by several factors previously shown to affect outcome in stroke, including glucose availability, intracellular pH, protein kinase ζ/δ, casein kinase 2, phosphoinositide-3-kinase, Rac1/2, and phospholipase A2. The newly identified functions of these factors as regulators of NOX2 activity suggest alternative mechanisms for their effects on ischemic brain injury.

CRITICAL ISSUES

Key aspects of these regulatory influences remain unresolved, including the mechanisms by which rac1 and phospholipase activities are coupled to N-methyl-D-aspartate (NMDA) receptors, and whether superoxide production by NOX2 triggers subsequent superoxide production by mitochondria.

FUTURE DIRECTIONS

It will be important to establish whether interventions targeting the signaling pathways linking NMDA receptors to NOX2 in brain ischemia can provide a greater neuroprotective efficacy or a longer time window to treatment than provided by NMDA receptor blockade alone. It will likewise be important to determine whether dissociating superoxide production from the other signaling events initiated by NMDA receptors can mitigate the deleterious effects of NMDA receptor blockade.

Combination approaches to attenuate hemorrhagic transformation after tPA thrombolytic therapy in patients with poststroke hyperglycemia/diabetes

To date, tissue type plasminogen activator (tPA)-based thrombolytic stroke therapy is the only FDA-approved treatment for achieving vascular reperfusion and clinical benefit, but this agent is given to only about 5% of stroke patients in the USA. This may be related, in part, to the elevated risk of symptomatic intracranial hemorrhage, and consequently limited therapeutic time window. Clinical investigations demonstrate that poststroke hyperglycemia is one of the most important risk factors that cause intracerebral hemorrhage and worsen neurological outcomes. There is a knowledge gap in understanding the underlying molecular mechanisms, and lack of effective therapeutics targeting the severe complication. This short review summarizes clinical observations and experimental investigations in preclinical stroke models of the field. The data strongly suggest that interactions of multiple pathogenic factors including hyperglycemia-mediated vascular oxidative stress and inflammation, ischemic insult, and tPA neurovascular toxicity in concert contribute to the BBB damage-intracerebral hemorrhagic transformation process. Development of combination approaches targeting the multiple pathological cascades may help to attenuate the hemorrhagic complication.

Thrombolysis for acute ischaemic stroke

BACKGROUND

Most strokes are due to blockage of an artery in the brain by a blood clot. Prompt treatment with thrombolytic drugs can restore blood flow before major brain damage has occurred and improve recovery after stroke in some people. Thrombolytic drugs, however, can also cause serious bleeding in the brain, which can be fatal. One drug, recombinant tissue plasminogen activator (rt-PA), is licensed for use in selected patients within 4.5 hours of stroke in Europe and within three hours in the USA. There is an upper age limit of 80 years in some countries, and a limitation to mainly non-severe stroke in others. Forty per cent more data are available since this review was last updated in 2009.

OBJECTIVES

To determine whether, and in what circumstances, thrombolytic therapy might be an effective and safe treatment for acute ischaemic stroke.

SEARCH METHODS

We searched the Cochrane Stroke Group Trials Register (last searched November 2013), MEDLINE (1966 to November 2013) and EMBASE (1980 to November 2013). We also handsearched conference proceedings and journals, searched reference lists and contacted pharmaceutical companies and trialists.

SELECTION CRITERIA

Randomised trials of any thrombolytic agent compared with control in people with definite ischaemic stroke.

DATA COLLECTION AND ANALYSIS

Two review authors applied the inclusion criteria, extracted data and assessed trial quality. We verified the extracted data with investigators of all major trials, obtaining additional unpublished data if available.

MAIN RESULTS

We included 27 trials, involving 10,187 participants, testing urokinase, streptokinase, rt-PA, recombinant pro-urokinase or desmoteplase. Four trials used intra-arterial administration, while the rest used the intravenous route. Most data come from trials that started treatment up to six hours after stroke. About 44% of the trials (about 70% of the participants) were testing intravenous rt-PA. In earlier studies very few of the participants (0.5%) were aged over 80 years; in this update, 16% of participants are over 80 years of age due to the inclusion of IST-3 (53% of participants in this trial were aged over 80 years). Trials published more recently utilised computerised randomisation, so there are less likely to be baseline imbalances than in previous versions of the review. More than 50% of trials fulfilled criteria for high-grade concealment; there were few losses to follow-up for the main outcomes.Thrombolytic therapy, mostly administered up to six hours after ischaemic stroke, significantly reduced the proportion of participants who were dead or dependent (modified Rankin 3 to 6) at three to six months after stroke (odds ratio (OR) 0.85, 95% confidence interval (CI) 0.78 to 0.93). Thrombolytic therapy increased the risk of symptomatic intracranial haemorrhage (OR 3.75, 95% CI 3.11 to 4.51), early death (OR 1.69, 95% CI 1.44 to 1.98; 13 trials, 7458 participants) and death by three to six months after stroke (OR 1.18, 95% CI 1.06 to 1.30). Early death after thrombolysis was mostly attributable to intracranial haemorrhage. Treatment within three hours of stroke was more effective in reducing death or dependency (OR 0.66, 95% CI 0.56 to 0.79) without any increase in death (OR 0.99, 95% CI 0.82 to 1.21; 11 trials, 2187 participants). There was heterogeneity between the trials. Contemporaneous antithrombotic drugs increased the risk of death. Trials testing rt-PA showed a significant reduction in death or dependency with treatment up to six hours (OR 0.84, 95% CI 0.77 to 0.93, P = 0.0006; 8 trials, 6729 participants) with significant heterogeneity; treatment within three hours was more beneficial (OR 0.65, 95% CI 0.54 to 0.80, P < 0.0001; 6 trials, 1779 participants) without heterogeneity. Participants aged over 80 years benefited equally to those aged under 80 years, particularly if treated within three hours of stroke.

AUTHORS' CONCLUSIONS

Thrombolytic therapy given up to six hours after stroke reduces the proportion of dead or dependent people. Those treated within the first three hours derive substantially more benefit than with later treatment. This overall benefit was apparent despite an increase in symptomatic intracranial haemorrhage, deaths at seven to 10 days, and deaths at final follow-up (except for trials testing rt-PA, which had no effect on death at final follow-up). Further trials are needed to identify the latest time window, whether people with mild stroke benefit from thrombolysis, to find ways of reducing symptomatic intracranial haemorrhage and deaths, and to identify the environment in which thrombolysis may best be given in routine practice.

Prediabetes in patients with stroke or transient ischemic attack: prevalence, risk and clinical management

BACKGROUND

The prevalence of diabetes is emerging worldwide and is an important modifiable risk factor for stroke. People with prediabetes, an intermediate metabolic state between normal glucose metabolism and diabetes, have a tenfold increased risk of developing diabetes compared to those with a normal glucose metabolism. Prediabetes is comprised of impaired fasting glucose and/or impaired glucose tolerance and/or disturbed glycosylated hemoglobin levels. Prediabetes is highly prevalent in nondiabetic patients with transient ischemic attack (TIA) or ischemic stroke and nearly doubles their risk of stroke. This offers new options for secondary stroke prevention.

SUMMARY

Several detection methods exist for identifying (pre)diabetes, including fasting plasma glucose, 2-hour postload glucose and glycosylated hemoglobin levels. The concordance between these tests is not 100%, and they seem to be complementary. Screening for (pre)diabetes after stroke with fasting plasma glucose levels alone is insufficient, and 2-hour postload glucose and/or glycosylated hemoglobin levels should be determined as well. The prevalence of prediabetes in previously nondiabetic patients with a recent TIA or stroke ranges from 23 to 53%. This high prevalence in the acute phase after stroke can be transient or persistent, representing undiagnosed abnormal glucose metabolism. Impaired fasting glucose and impaired glucose tolerance have different pathophysiological mechanisms, including hepatic insulin resistance and muscle insulin resistance, respectively. Prediabetes seems to be a modest predictor for stroke, but doubles the risk for recurrent stroke. The relation between prediabetes after stroke and functional outcome is still unknown. However, it is most likely that prediabetes is a risk factor for a poor clinical outcome after stroke. There is a growing recognition that patients with prediabetes should be treated more aggressively. Both lifestyle and pharmacological interventions are possible treatment strategies. They are at least equally effective in preventing progression to diabetes. Lifestyle changes are difficult to maintain over a long period. The evidence of pharmacological interventions on stroke or other cardiovascular diseases is limited though and is still subject of several clinical trials.

CONCLUSIONS

As the prevalence of prediabetes is growing rapidly, prediabetes might become one of the most important modifiable therapeutic targets in both primary and secondary prevention.

Proteomic Protease Substrate Profiling of tPA Treatment in Acute Ischemic Stroke Patients: A Step Toward Individualizing Thrombolytic Therapy at the Bedside

Tissue plasminogen activator (tPA) is the only FDA-approved medical therapy for acute ischemic stroke. But as a serine peptidase, intravenous tPA can affect the expression of other proteases that may be implicated in blood-brain barrier breakdown. Such parallel cascades of cell signaling may be involved in intracranial hemorrhage, the major side effect of tPA. Here, we describe an initial attempt in proteomic substrate profiling, i.e., degradomics in human plasma within the context of acute stroke. Plasma from acute stroke patients were analyzed pre- and post-intravenous tPA using tandem mass spectrometry and protein array profiling to identify substrates and proteases of interest. In non-tPA-treated stroke plasma, degradomic patterns indicated a rapid induction of protease activity within 3 h of stroke onset that mostly stabilized by 24 h. But in tPA-treated patients, pre- and post-tPA samples from the same patient demonstrated distinct degradomic patterns that persisted even up to 3-5 days after stroke onset. Matching control patients without strokes had little change in degradomic profiles over time. Our findings demonstrate that tPA treatment changes the plasma degradomic profiles in acute stroke patients. These composite proteolytic profiles may provide a glimpse of the pleiotropic effects of tPA on cellular signaling cascades at the bedside. This study supports the feasibility of performing pharmaco-proteomics at the bedside, which may ultimately allow us to dissect mechanisms of thrombolysis-related therapeutic efficacy in stroke.

Evaluation of IScore validity in a Greek cohort of patients with type 2 diabetes

Background

Diabetes constitutes a risk factor for stroke that also aggravates stroke prognosis. Several prognostic models have been developed for the evaluation of neurologic status, severity, short-term functional outcome and mortality of stroke patients. IScore is a novel tool recently developed in order to predict mortality rates within 30 days and 1 year after ischemic stroke and diabetes is not included in the scoring scale of IScore. The aim of the present study was to evaluate and compare IScore validity in ischemic stroke patients with and without diabetes.

Methods

This prospective study included 312 consecutive Caucasian patients with type 2 diabetes and 222 Caucasian patients without diabetes admitted for ischemic stroke in a tertiary Greek hospital. Thirty-day and 1-year IScores were individually calculated for each patient and actual mortality was monitored at the same time intervals. IScore’s predictive ability and calibration was evaluated and compared for ischemic stroke patients with and without diabetes. The performance of IScore for predicting 30 and 1-year mortality between patients with and without diabetes was assessed by determining the calibration and discrimination of the score. The area under the receiver operating characteristic curve was used to evaluate the discriminative ability of IScore for patients with and without diabetes, whereas the calibration of IScore was assessed by the Hosmer–Lemeshow goodness-of fit statistic.

Results

Baseline population characteristics and mortality rates did not differ significantly for both cohorts. IScore values were significantly higher for patients with diabetes at 30 days and 1 year after ischemic stroke and patients with diabetes presented more frequently with lacunar strokes. Based on ROC curves analysis IScore’s predictive ability for 30 day mortality was excellent, without statistically significant difference, for both cohorts. Predictive ability for 1 year mortality was also excellent for both groups with significantly better ability for patients with diabetes especially at high score values. Calibration of the model was good for both groups of patients.

Conclusions

IScore accurately predicts mortality in acute ischemic stroke Caucasian patients with and without diabetes with higher efficacy in predicting 1 year mortality in patients with diabetes especially with high scores.

The taxonomy statistic uncovers novel clinical patterns in a population of ischemic stroke patients

In this paper, we describe a simple taxonomic approach for clinical data mining elaborated by Marczewski and Steinhaus (M-S), whose performance equals the advanced statistical methodology known as the expectation-maximization (E-M) algorithm. We tested these two methods on a cohort of ischemic stroke patients. The comparison of both methods revealed strong agreement. Direct agreement between M-S and E-M classifications reached 83%, while Cohen's coefficient of agreement was κ = 0.766(P < 0.0001). The statistical analysis conducted and the outcomes obtained in this paper revealed novel clinical patterns in ischemic stroke patients. The aim of the study was to evaluate the clinical usefulness of Marczewski-Steinhaus' taxonomic approach as a tool for the detection of novel patterns of data in ischemic stroke patients and the prediction of disease outcome. In terms of the identification of fairly frequent types of stroke patients using their age, National Institutes of Health Stroke Scale (NIHSS), and diabetes mellitus (DM) status, when dealing with rough characteristics of patients, four particular types of patients are recognized, which cannot be identified by means of routine clinical methods. Following the obtained taxonomical outcomes, the strong correlation between the health status at moment of admission to emergency department (ED) and the subsequent recovery of patients is established. Moreover, popularization and simplification of the ideas of advanced mathematicians may provide an unconventional explorative platform for clinical problems.

Pharmaco-proteomics opportunities for individualizing neurovascular treatment

Neurovascular disease often involves multi-organ system injury. For example, patent foramen ovale (PFO) related ischemic strokes involve not just the brain, but also the heart, the lung, and the peripheral vascular circulation. For higher-risk but high-reward systemic therapy (e.g., thrombolytics, therapeutic hypothermia (TH), PFO closure) to be implemented safely, very careful patient selection and close monitoring of disease progression and therapeutic efficacy are imperative. For example, more than a decade after the approval of therapeutic hypothermic and intravenous thrombolysis treatments, they both remain extremely under-utilized, in part due to lack of clinical tools for patient selection or to follow therapeutic efficacy. Therefore, in understanding the complexity of the global effects of clinical neurovascular diseases and their therapies, a systemic approach may offer a unique perspective and provide tools with clinical utility. Clinical proteomic approaches may be promising to monitor systemic changes in complex multi-organ diseases - especially where the disease process can be 'sampled' in clinically accessible fluids such as blood, urine, and CSF. Here, we describe a 'pharmaco-proteomic' approach to three major challenges in translational neurovascular research directly at bedside - in order to better stratify risk, widen therapeutic windows, and explore novel targets to be validated at the bench - (i) thrombolytic treatment for ischemic stroke, (ii) therapeutic hypothermia for post-cardiac arrest syndrome, and (iii) treatment for PFO related paradoxical embolic stroke. In the future, this clinical proteomics approach may help to improve patient selection, ensure more precise clinical phenotyping for clinical trials, and individualize patient treatment.

Effects of minocycline plus tissue plasminogen activator combination therapy after focal embolic stroke in type 1 diabetic rats

BACKGROUND AND PURPOSE

Poststroke hyperglycemia is associated with resistance to tissue plasminogen activator (tPA) reperfusion, higher risk of intracerebral hemorrhage, and worse neurological outcomes. In this study, we asked whether minocycline combined with intravenous tPA may ameliorate inflammation and brain injury after focal embolic stroke in type 1 diabetic rats.

METHODS

Type 1 diabetic rats were subjected to a focal embolic stroke. Three treatment groups were used: (1) saline at 1.5 hours after stroke; (2) tPA alone at 1.5 hours after stroke; (3) combined minocycline (intravenously) at 1 hour plus tPA at 1.5 hours, and second treatment of minocycline (intraperitoneally) at 12 hours after stroke. Acute brain tissue damages were assessed at 24 hours after stroke. Inflammatory biomarkers interleukin-1β and matrix metalloproteinases 2 and 9 were examined in plasma. Neutrophil infiltration, microglia activation, matrix metalloproteinase activation, and degradation of the tight junction protein claudin-5 were examined in the brain.

RESULTS

Compared with saline or tPA alone treatments, minocycline plus tPA combination therapy significantly reduced brain infarction, intracerebral hemorrhage, and hemispheric swelling at 24 hours after stroke. The combination also significantly suppressed the elevated plasma levels of matrix metalloproteinase-9 and interleukin-1β up to 24 hours after stroke. At 16 hours after stroke, neutrophil infiltration, microglia activation, matrix metalloproteinase-9, and tight junction protein claudin-5 degradation in the peri-infarct brain tissues were also significantly attenuated by the combination therapy.

CONCLUSIONS

Combination therapy with minocycline plus tPA may be beneficial in ameliorating inflammation and reducing infarction, brain swelling, and hemorrhage after ischemic stroke with diabetes mellitus/hyperglycemia.

Considering hyperglycemia and thrombolysis in the Stroke Hyperglycemia Insulin Network Effort (SHINE) trial

Hyperglycemia is associated with enhanced cortical toxicity and larger infarct volumes following focal cerebral ischemia. Initial blood glucose in acute ischemic stroke patients may also contribute to a differential response to thrombolysis (i.e., administration of tissue plasminogen activator (t-PA)) and affect risk of symptomatic intracerebral hemorrhage (sICH). The Stroke Hyperglycemia Insulin Network Effort (SHINE) study is a phase III single-blinded, randomized control trial comparing an intensive level of glucose control with standard of care glucose control in hyperglycemic stroke patients. In stratifying randomization by treatment with intravenous t-PA, the SHINE trial offers a unique opportunity to evaluate an association between euglycemic control and outcomes from stroke thrombolysis in a prospective, comparative study. We hypothesize that normalization of blood glucose in the acute stroke setting may reduce risk of thrombolysis-induced sICH. With enrollment recently underway, the stratified results from the SHINE trial could substantially influence future treatment decisions for hyperglycemic stroke patients.

Ischemic vagus nuclei lesions and hyperglycemia: a study in 26 patients with lateral medullary infarction and matched controls

BACKGROUND

Hyperglycemia is common after stroke in diabetic and nondiabetic patients. Furthermore, it has been associated with infarct expansion, worse functional outcomes and higher mortality. In a previous study, infarction of the insular region was related to higher poststroke glucose levels than infarcts in other cortical areas. Experimental studies in animal models suggested that the lower brainstem nuclei of the vagus nerve modulate insulin secretion. These nuclei are usually affected in lateral medullary infarction (LMI). We evaluated whether patients with lateral medullary stroke have worse poststroke glycemic control than other stroke patients.

METHODS

A hospital-based stroke registry was used to identify 26 patients from the years 2000 to 2010 who fulfilled the following inclusion criteria: (1) a first-ever stroke; (2) neurological deficits compatible with LMI; (3) MRI confirmation of an ischemic lesion of the lateral medulla involving the vagus nerve nuclei, and (4) no simultaneous infarcts. Patients were excluded if they were admitted to the hospital more than 24 h after stroke onset or died in the first 24 h after hospital admission. A control group of other stroke patients was randomly selected from the same stroke registry and over the same time period, matching for the age and gender of the LMI group. The average glycemia was compared between the two groups using a linear regression model adjusted for confounders. Glycated hemoglobin at admission was used to estimate prestroke glycemic control. Prestroke glycemic averages were then compared with poststroke glycemia for the two groups using the Wilcoxon signed test for related samples.

RESULTS

The average glycemia of the LMI patients in the first 24 h after stroke was 9.4 mmol/l (SD 3.2), and from 24 to 72 h it was 7.6 mmol/l (SD 2.8). In the comparison group, these values were 7.7 (SD 2.8) and 7.1 mmol/l (SD 2.7), respectively. As expected, diabetic patients had a significantly higher glycemia than nondiabetic patients (p < 0.0001). The adjusted linear regression model showed the average glycemia differences to be significant for the first 24 h (p = 0.001; R(2) = 55.6%) but not for the 24- 72 h period. The frequency of previous diabetes mellitus was similar in both groups. As compared to prestroke glycemic estimates, glycemia in lateral medullary stroke patients increased significantly more than in controls during the first 24 h after stroke (p = 0.01), but again there were no significant differences for the 24-72 h period.

CONCLUSIONS

This study suggests that ischemic lesions of the vagus nerve nuclei are associated with worse early poststroke glycemic control than stroke in other locations. Confirmation of this hypothesis and the long-term implications of glucose control impairment warrant further prospective studies.

Impact of Admission Glucose and Diabetes on Recanalization and Outcome after Intra-Arterial Thrombolysis for Ischaemic Stroke

Background

Stroke patients with diabetes and admission hyperglycaemia have worse outcomes than non-diabetics, with or without intravenous thrombolysis. Poor vessel recanalization was reported in diabetics treated with intravenous thrombolysis.

Aims

This study aimed to determine the impact of admission glucose and diabetes on recanalization and outcome after intra-arterial thrombolysis.

Methods

We analysed 389 patients (213 men, 176 women) treated with intra-arterial thrombolysis. The association of diabetes and admission glucose value with recanalization, outcome, mortality, and symptomatic intracranial haemorrhage was determined. Recanalization was classified according to thrombolysis in myocardial infarction grades. Outcome was measured using the modified Rankin Scale at three-months and categorized as favourable (modified Rankin Scale 0–2) or poor (modified Rankin Scale 3–6).

Results

The rate of partial or complete recanalization (thrombolysis in myocardial infarction 2–3) did not differ between patients with and without diabetes (67% vs. 66%; P = 1·000). Mean admission glucose values were similar in patients with poor recanalization (thrombolysis in myocardial infarction 0–1) and patients with partial or complete recanalization (thrombolysis in myocardial infarction 2–3; 7·3 vs. 7·3 mmol/l; P = 0·746). Follow-up at three-months was obtained in 388 of 389 patients. Clinical outcome was favourable (modified Rankin Scale 0–2) in 189 patients (49%) and poor (modified Rankin Scale 3–6) in 199 patients (51%). Mortality at three-months was 20%. Diabetics were more likely to have poor outcome (72% vs. 48%; P = 0·001) and to be dead (30% vs. 19%; P = 0·044) at three-months. After multivariable analysis, there remained an independent relationship between diabetes and outcome ( P = 0·003; odds ratio 3·033, 95% confidence interval 1·452–6·336), but not with mortality ( P = 0·310; odds ratio 1·436; 95% confidence interval 0·714–2·888). Moreover, higher age ( P = 0·001; odds ratio 1·039; 95% confidence interval 1·017–1·061), higher baseline National Institutes of Health Stroke Scale score ( P < 0·0001; odds ratio 1·130; 95% confidence interval 1·079–1·182), location of vessel occlusion as categorical variable ( P < 0·0001), poor collaterals ( P = 0·02; odds ratio 1·587; 95% confidence interval 1·076–2·341), poor vessel recanalization ( P < 0·0001; odds ratio 4·713; 95% confidence interval 2·627–8·454), and higher leucocyte count ( P = 0·032; odds ratio 1·094; 95% confidence interval 1·008–1·188) were independent baseline predictors of poor outcome. Higher admission glucose was associated with poor outcome ( P = 0·006) and mortality ( P < 0·0001). After multivariate analyses, glucose remained independently associated with poor outcome ( P = 0·019; odds ratio 1·150; 95% confidence interval 1·023-1-292) and mortality ( P = 0·005; odds ratio 1·183; 95% confidence interval 1052–1·331). The rate of symptomatic intracranial haemorrhage was similar in diabetics and non-diabetics (6·7% vs. 4·6%; P = 0·512). Mean admission glucose was higher in patients with symptomatic intracranial haemorrhage than without (8·58 vs. 7·26 mmol/l; P = 0·010). Multivariable analysis confirmed an independent association between admission glucose and symptomatic intracranial haemorrhage ( P = 0·027; odds ratio 1·187; 95% confidence interval 1·020–1·381).

Conclusions

Diabetes and glucose value on admission did not influence recanalization after intra-arterial thrombolysis; nevertheless, they were independent predictors of poor outcome after intra-arterial thrombolysis and a higher admission glucose value was an independent predictor of symptomatic intracranial haemorrhage. This indicates that factors on the capillary, cellular, or metabolic level may account for the worse outcome in patients with elevated glucose value and diabetes.

Higher Blood Glucose within the Normal Range Is Associated with More Severe Strokes

Background. Higher fasting blood glucose (FBG) concentrations in the hyperglycemic range are associated with more severe strokes. Whether this association also extends into patients with FBG in the normoglycemic range is unclear. We studied the association of stroke severity and FBG in normoglycemic patients with ischemic stroke in a median of 7 days after stroke when the initial glycemic stress response has resolved. Method and Material. Included were 361 nondiabetic ischemic stroke patients with admission fasting blood glucose within 70–130 mg/dL admitted into an acute stroke rehabilitation unit in a median of 7 days after stroke. Data including neuroimaging, vital signs, cardiovascular risk factors, and admission functional independence measure (AFIM) were recorded prospectively. Results. FBG correlated with stroke severity in the normoglycemic 70–130 mg/dL range (FBG-AFIM correlation coefficient −0.17; P = 0.003). Odds ratio for more severe injury (below average AFIM score) was 2.02 for patients with FBG 110–130 mg/dL compared to FBG 70–90 mg/dL (95% confidence interval 1.10–3.73, P = 0.022). Each mg/dL increase in FBG was associated with an average decrease of 0.25 FIM points. In a multiple linear regression model, FBG was associated with more severe stroke (P = 0.002). Conclusion. One week after ischemic stroke, FBG within the normoglycemic range was associated with stroke severity.

A simple clinical and MRI scale to predict good outcome in t-PA patients

BACKGROUND AND PURPOSE

The frequency of good outcome at 3 months after tissue plasminogen activator (t-PA) therapy is ∼35%. The present study aimed to devise a simple scale to predict good outcome using clinical factors and magnetic resonance imaging (MRI) findings before and immediately after t-PA infusion.

METHODS

Consecutive patients with acute ischemic stroke treated with t-PA within 3 hours of stroke onset were studied prospectively. We assessed clinical factors independently associated with good outcome [modified Rankin scale (mRS): 0-1] at 3 months after t-PA therapy. We created a simple scale to predict good outcome in t-PA patients using factors selected by multivariate logistic regression analysis.

RESULTS

Subjects comprised 105 patients (69 men; median age, 74 years). Multivariate logistic regression analysis revealed the following independent factors associated with good outcome: baseline National Institutes of Health Stroke Scale (NIHSS) <11 [odds ratio (OR), 13·64; 95% confidence interval (CI), 3·588-51·822; P = 0·0001], glucose <150 mg/dl (OR, 3·76; 95%CI, 1·014-13·963; P = 0·0475), and early recanalization within 1 hour after t-PA infusion (OR, 5·28; 95%CI, 1·179-23·656; P = 0·0296). Those three variables were selected for use in the good outcome scale, with NIHSS <11 as 2 points, glucose <150 mg/dl as 1 point, and early recanalization as 1 point. Frequencies of patients with good outcome for each score were as follows: score 0, 0·0%; score 1, 7·1%; score 2, 43·5%; score 3, 65·4%; and score 4, 71·4%. The C statistic for the score was 0·849 (95%CI, 0·776-0·922).

CONCLUSION

A simple clinical and MRI scale can predict good outcome in t-PA patients.

An intravenous insulin protocol for strict glycemic control in acute ischaemic stroke

BACKGROUND AND PURPOSE

There is a J-shaped association between admission glycemia and outcome. We designed an intravenous insulin protocol aiming at rapid and strict glucose control in hyperglycemic ischaemic stroke patients. Here, we describe the initial experience, safety, and efficacy of this protocol to achieve and maintain euglycemia in the first 48h.

METHODS

The protocol is based on parallel scales for adjustment of insulin infusion rate according to current glycemia and the rate of change of glycemia, which was recommended in our stroke unit in 4/2007 in acute ischaemic stroke patients with glycemia >6mM. Data were registered in the Acute Stroke Registry and Analysis of Lausanne (ASTRAL). Capillary blood glycemia was measured hourly with fingerprick test at onset of treatment and after each scale change. Target glycemia was 4.0-6.0mM pre-prandially (5.5-8.0mM post-prandially). Hypokalemia was defined as serum potassium <3.5mM and measured every 12h. Specific algorithms were employed during meals and for patients leaving temporarily the stroke unit for diagnostic or therapeutic workup.

RESULTS

In the 90 protocol patients, the first normoglycemia was achieved within 8h of treatment in 91.1% of patients (median interval 4h (interquartile range (IQR): 3-6). During the median treatment duration of 25.5h (IQR: 19.7-37.7), median glucose reduction was 2.5mM (IQR: 1.3-4.3mM). The overall rate of hypoglycemias was 4.5% and hypokalemias 18.5%. There was a significant increase in the proportion of hypokalemias on the first on-treatment measurement compared to admission (24.4% vs. 8.9%, P=0.002).

CONCLUSIONS

The proposed intravenous insulin protocol controls acute post-stroke hyperglycemia but frequently leads to hypokalemia. This issue needs to be addressed for the protocol to be suitable for use in larger, randomized controlled trial to explore its clinical effect.

Hyperglycemia promotes tissue plasminogen activator-induced hemorrhage by Increasing superoxide production

OBJECTIVE

Risk of intracerebral hemorrhage is the primary factor limiting use of tissue plasminogen activator (tPA) for stroke. Clinical studies have established an association between admission hyperglycemia and the risk of hemorrhage with tPA use, independent of prior diabetes. Here we used an animal model of tPA-induced reperfusion hemorrhage to determine if this clinical association reflects a true causal relationship.

METHODS

Rats underwent 90 minutes of focal ischemia, and tPA infusion was begun 10 minutes prior to vessel reperfusion. Glucose was administered during ischemia to generate blood levels ranging from 5.9 ± 1.8mM (normoglycemia) to 21 ± 2.3mM. In some studies, apocynin was administered to block superoxide production by nicotinamide adenine dinucleotide phosphate (NADPH). Brains were harvested 1 hour or 3 days after reperfusion to evaluate the effects of hyperglycemia and apocynin on oxidative stress, blood-brain barrier breakdown, infarct volume, and hemorrhage volume.

RESULTS

Rats that were hyperglycemic during tPA infusion had diffusely increased blood-brain barrier permeability in the postischemic territory, and a 3- to 5-fold increase in intracerebral hemorrhage volumes. The hyperglycemic rats also showed increased superoxide formation in the brain parenchyma and vasculature during reperfusion. The effects of hyperglycemia on superoxide production, blood-brain barrier disruption, infarct size, and hemorrhage were all attenuated by apocynin.

INTERPRETATION

These findings demonstrate a causal relationship between hyperglycemia and hemorrhage in an animal model of tPA stroke treatment, and suggest that this effect of hyperglycemia is mediated through an increase in superoxide production by NADPH oxidase.

Adverse effects of bone marrow stromal cell treatment of stroke in diabetic rats

BACKGROUND AND PURPOSE

Cell therapy with bone marrow stromal cells (BMSCs) improves functional recovery after stroke in nondiabetic rats. However, its effect on diabetics with stroke is unknown. This study investigated the effect of BMSCs on stroke outcome in Type 1 diabetic (T1DM) rats.

METHODS

T1DM was induced in adult male Wistar rats by injecting streptozotocin. Nondiabetic and T1DM rats were subjected to 2 hours of middle cerebral artery occlusion (MCAO), treated with or without BMSCs (3×10(6)) at 24 hours after MCAO, and monitored for 14 days.

RESULTS

Functional benefit was not detected in T1DM-MCAO treated with BMSC rats compared with corresponding T1DM-MCAO controls. BMSC treatment in T1DM-MCAO rats had increased mortality, blood-brain barrier leakage, brain hemorrhage, and angiogenesis. Internal carotid artery neointimal formation and cerebral arteriole narrowing/occlusion were also observed in T1DM-MCAO+BMSCs rats compared with T1DM-MCAO controls (P<0.05), but not in nondiabetic stroke rats. We further studied the underlying mechanisms responsible for BMSC-induced blood-brain barrier leakage and accelerated vascular damage in T1DM-MCAO rats. We found that the expression of angiogenin (an angiogenic factor) and ED1 (a marker for macrophages) was significantly increased in the T1DM-MCAO+BMSC rats in the ischemic brain and internal carotid artery compared with nontreated T1DM-MCAO rats, but not in nondiabetic stroke rats.

CONCLUSIONS

BMSC therapy in T1DM-MCAO rats does not improve functional outcome. On the contrary, it increases blood-brain barrier leakage and cerebral artery neointimal formation, and arteriosclerosis, which possibly is due to increased expression of angiogenin. Thus, BMSC treatment starting 24 hours after MCAO may not be beneficial for diabetic subjects with stroke.

[Difficult decisions in stroke therapy]

In numerous situations stroke physicians face a lack of evidence during their daily practice. In this report the authors address some of the difficult treatment decisions encountered in acute therapy and secondary prevention. Examples include off-label thrombolysis and prevention in high-risk situations. The available data from trials and registries are discussed, and personal views and recommendations are expressed.

Management of blood glucose in patients with stroke

Stroke is a leading cause of death worldwide and the most common cause of long-term disability amongst adults, more particularly in patients with diabetes mellitus and arterial hypertension. Increasing evidence suggests that disordered physiological variables following acute ischaemic stroke, especially hyperglycaemia, adversely affect outcomes. Post-stroke hyperglycaemia is common (up to 50% of patients) and may be rather prolonged, regardless of diabetes status. A substantial body of evidence has demonstrated that hyperglycaemia has a deleterious effect upon clinical and morphological stroke outcomes. Therefore, hyperglycaemia represents an attractive physiological target for acute stroke therapies. However, whether intensive glycaemic manipulation positively influences the fate of ischaemic tissue remains unknown. One major adverse event of management of hyperglycaemia with insulin (either glucose-potassium-insulin infusions or intensive insulin therapy) is the occurrence of hypoglycaemia, which can also induce cerebral damage. Novel insights into post-stroke hyperglycaemia management have been derived from continuous glucose monitoring systems (CGMS). This article aims: 1) to describe the adverse effects of hyperglycaemia following acute ischaemic stroke and the risk associated with iatrogenic hypoglycaemia; 2) to summarise the evidence from current glucose-lowering treatment trials; and 3) to show the usefulness of CGMS in both non-diabetic and diabetic patients with acute stroke.

Prevalence, Predictors and Prognosis of Post-Stroke Hyperglycaemia in Acute Stroke Trials: Individual Patient Data Pooled Analysis from the Virtual International Stroke Trials Archive (VISTA)

Background

Post-stroke hyperglycaemia (PSH) is associated with higher mortality and dependence, but further data on predictors of PSH and its evolution over time are required. We examined the prevalence, predictors, and prognosis of acute PSH using data from well-characterised clinical trials in the VISTA database.

Methods

Data were extracted for individual participants enrolled <24 h after stroke with ≥1 blood glucose readings documented. PSH was defined as glucose >7.0 mmol/l. Outcome measures were: (1) prevalence of PSH; (2) predictors of PSH by binary logistic regression; (3) mortality, and (4) favourable functional outcome [modified Rankin Scale (mRS) score <2] at day 90.

Results

For 2,649 subjects treated at a median 5.5 h after admission, PSH was present in 1,126 (42.6%, 95% CI 40.7–44.5) on admission and within the first 48 h in 1,421 (53.7%, 95% CI 51.8–55.6). PSH developed between 24 and 48 h in 19.4% (95% CI 17.5–21.4) of initially normoglycaemic subjects. Admission and 48-hour PSH were predicted predominantly by a history of diabetes (for admission PSH: OR 7.40, 95% CI 5.60–9.79) and less clearly by stroke severity. Favourable outcome (mRS <2) at day 90 was less likely with PSH within the first 48 h, advanced age, and higher NIHSS score, and more likely with recombinant tissue plasminogen activator treatment.

Conclusions

Over 40% of ischaemic stroke patients are hyperglycaemic on admission, and 20% of those who are initially normoglycaemic develop hyperglycaemia within 48 h. Diabetes is the strongest predictor of acute hyperglycaemia. Hyperglycaemia within the first 48 h is independently associated with higher mortality and poorer functional outcome, with an absolute increase of 12.9%.