Admission hyperglycemia and outcome after intravenous thrombolysis: is there a difference among the stroke-subtypes?

The RAGE Axis: A Relevant Inflammatory Hub in Human Diseases

In 1992, a transcendental report suggested that the receptor of advanced glycation end-products (RAGE) functions as a cell surface receptor for a wide and diverse group of compounds, commonly referred to as advanced glycation end-products (AGEs), resulting from the non-enzymatic glycation of lipids and proteins in response to hyperglycemia. The interaction of these compounds with RAGE represents an essential element in triggering the cellular response to proteins or lipids that become glycated. Although initially demonstrated for diabetes complications, a growing body of evidence clearly supports RAGE's role in human diseases. Moreover, the recognizing capacities of this receptor have been extended to a plethora of structurally diverse ligands. As a result, it has been acknowledged as a pattern recognition receptor (PRR) and functionally categorized as the RAGE axis. The ligation to RAGE leads the initiation of a complex signaling cascade and thus triggering crucial cellular events in the pathophysiology of many human diseases. In the present review, we intend to summarize basic features of the RAGE axis biology as well as its contribution to some relevant human diseases such as metabolic diseases, neurodegenerative, cardiovascular, autoimmune, and chronic airways diseases, and cancer as a result of exposure to AGEs, as well as many other ligands.

Association of HbA1c with functional outcome by ischemic stroke subtypes and age

Objectives

To determine whether high HbA1c levels are related to short-and long-term functional outcomes in patients with ischemic stroke (IS) and whether this association differs according to the IS subtype and the patient's age.

Methods

The data of 7,380 IS patients admitted to 16 hospitals or regional stroke centers in South-Korea, between May 2017 and December 2019, were obtained from the Clinical Research Collaboration for Stroke-Korea-National Institute of Health database and retrospectively analyzed. Among these patients, 4,598 were followed-up for one-year. The HbA1c levels were classified into three groups (<5.7, 5.7 to <6.5%, ≥6.5%). Short-and long-term poor functional outcomes were defined using the modified Rankin Scale score of 2 to 6 at three-months and one-year, respectively. IS subtypes were categorized according to the Trial of ORG 10172 in Acute Stroke Treatment (TOAST) classification.

Results

There was an association between higher HbA1c (≥6.5%) and poor functional outcomes at three-months in all patients (three-months; OR, 1.299, 95% CI 1.098, 1.535, one-year; OR, 1.181, 95% CI 0.952, 1.465). When grouped by age, the associations after both 3 months and 1 year observed in younger adult group (<65 years), but not in group aged 65 years and older (three-months; <65 years OR, 1.467, 95% CI 1.112, 1.936, ≥65 years OR, 1.220, 95% CI 0.987, 1.507, p for interaction = 0.038, one-year; <65 years OR, 1.622, 95% CI 1.101, 2.388, ≥65 years OR, 1.010, 95% CI 0.778, 1.312, p for interaction = 0.018). Among younger adult group, the higher HbA1c level was related to short-and long-term functional loss in patients with the small vessel occlusion subtype (three-months; OR, 2.337, 95%CI 1.334, 4.095, one-year; OR, 3.004, 95% CI 1.301, 6.938). However, in patients with other TOAST subtypes, a high HbA1c level did not increase the risk of poor outcomes, regardless of the age of onset.

Conclusion

High HbA1c levels increase the risk of short-and long-term poor functional outcomes after IS onset. However, this association differs according to stroke subtype and age. Thus, pre-stroke hyperglycemia, reflected by HbA1c, may be a significant predictor for a poor prognosis after ischemic stroke, particular in young- and middle-aged adults.

The Prognostic Significance of Early Glycemic Profile in Acute Ischemic Stroke Depends on Stroke Subtype

It is still unclear whether early glycemic profile after admission for acute ischemic stroke (IS) has the same prognostic significance in patients with lacunar and non-lacunar infarction. Data from 4011 IS patients admitted to a Stroke Unit (SU) were retrospectively analyzed. Lacunar IS was diagnosed by clinical criteria. A continuous indicator of early glycemic profile was calculated as the difference of fasting serum glucose (FSG) measured within 48 h after admission and random serum glucose (RSG) measured on admission. Logistic regression was used to estimate the association with a combined poor outcome defined as early neurological deterioration, severe stroke at SU discharge, or 1-month mortality. Among patients without hypoglycemia (RSG and FSG > 3.9 mmol/L), an increasing glycemic profile increased the likelihood of a poor outcome for non-lacunar (OR, 1.38, 95%CI, 1.24-1.52 in those without diabetes; 1.11, 95%CI, 1.05-1.18 in those with diabetes) but not for lacunar IS. Among patients without sustained or delayed hyperglycemia (FSG < 7.8 mmol/L), an increasing glycemic profile was unrelated to outcome for non-lacunar IS but decreased the likelihood of poor outcome for lacunar IS (OR, 0.63, 95%CI, 0.41-0.98). Early glycemic profile after acute IS has a different prognostic significance in non-lacunar and lacunar patients.

Effects of Hyperferritinemia on Functional Outcome in Acute Ischemic Stroke Patients with Admission Hyperglycemia

INTRODUCTION

Hyperferritinemia, presented as elevated serum ferritin level, is an indicator of high iron status which plays roles in secondary brain injury after acute ischemic stroke (AIS). However, the effects of hyperferritinemia and poor outcomes remain uncertain. Additionally, admission hyperglycemia quite frequently accompanies AIS patients, which is associated with unfavorable outcome. Thus, we aimed to investigate the effects of hyperferritinemia on 3-month and 1-year functional outcomes in AIS patients and especially those with admission hyperglycemia.

METHODS

AIS patients within 24 h of onset were enrolled at West China Hospital from October 2016 to December 2019. Serum ferritin and blood glucose levels were tested on admission. Poor functional outcome at 3 months and 1 year was defined as modified Rankin Scale score ≥3. Multivariable analysis was used to investigate the associations between hyperferritinemia and 3-month and 1-year outcomes. Subgroup analysis was performed in patients with and without hyperglycemia.

RESULTS

Of 723 patients (mean age 68.11 years, 60.6% males) finally included, 347 (48.0%) had hyperferritinemia. The incidence of poor outcome was 45.2% at 3 months and 41.2% at 1 year. Patients with hyperferritinemia had a higher frequency of poor 3-month outcome (51.8% vs. 39.2%, p = 0.001) and poor 1-year outcome (46.8% vs. 36.1%, p = 0.004). In all AIS patients, hyperferritinemia was not independently associated with poor functional outcome at 3 months or 1 year after adjusting for confounders (all p > 0.05). In AIS patients with hyperglycemia, hyperferritinemia was an independent factor correlated with poor 3-month outcome (OR = 1.711, 95% CI 1.093-2.681, p = 0.019) but not with poor 1-year outcome (p > 0.05).

CONCLUSIONS

High iron status, presented as hyperferritinemia, is associated with poor 3-month functional outcome in AIS patients with hyperglycemia. Evaluating serum ferritin level may be conducive to assess the risk of short-term poor outcome in AIS patients with hyperglycemia. Further studies will be required to confirm our findings.

Systematic Review of Existing Stroke Guidelines: Case for a Change

Methods

We systematically searched for guideline recommendation on the day-to-day use of peripheral inflammatory markers such as NLR published in the English language between January 1, 2005, and October 2020. Any other evidence of system biology-based approach or recommendation was explored within the selected guidelines for this scoping review. Only the latest guideline per writing group was selected. Each guideline was analyzed independently by 2 to 4 authors to determine clinical scenarios explained/given, scientific evidence used, and recommendations presented in the context of system biology.

Results

The scoping review found 2,911 titles at the beginning of the search. Final review included with 15 guidelines. Stroke-related organizations wrote sixty-five percent of the guidelines while national ministries wrote a fewer number of guidelines. We were primarily interested in recommendations for acute management in AIS published in the English language. Fifteen eligible guidelines were identified from 15 different countries/regions. None of the guidelines recommended the routine use of peripheral markers of inflammation, such as NLR, among their acute assessment and management recommendations. None of the existing guidelines explored the system biology approach to one of the most complex diseases affecting the human brain, stroke.

Conclusions

This systematic review has identified a significant evidence-practice gap in all existing national stroke guidelines published in English medium as of October 2020. These guidelines included the only current "living stroke guidelines," stroke guidelines from Australia with a real opportunity to modernize the living stroke guidelines with systems biology approach, and provide 2020 vision towards better stroke care globally. Investigation of complex disease such as stroke is best served through a systems biology approach. One of the easiest places to start is simple blood tests such as total white cell count and NLR. Systems biology approach point us towards simple tools such immune-inflammatory index (SII) and serial systemic immune inflammatory indices (SSIIi) which should pave the way for the stroke physician community address the challenges in systems biology approach in stroke care. These challenges include translating bench research to the bedside, managing big data (continuous pulse, blood pressure, sleep, oxygen saturation, progressive changes in NLR, SII, SSIIi, etc.). Working with an interdisciplinary team also provides a distinct advantage. Recent adoption of historic WHO-IGAP calls for immediate action. The 2022 World Brain Day campaign on Brain Health for All is the perfect opportunity to raise awareness and start the process.

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.

Coagulation markers and functional outcome in acute ischemic stroke: Impact of intensive versus standard hyperglycemia control

OBJECTIVE

Alterations in coagulation could mediate functional outcome in patients with hyperglycemia after acute ischemic stroke (AIS). We prospectively studied the effects of intensive versus standard glucose control on coagulation markers and their relationships to functional outcomes in patients with AIS.

APPROACH

The Insights on Selected Procoagulation Markers and Outcomes in Stroke Trial measured the coagulation biomarkers whole blood tissue factor procoagulant activity (TFPCA); plasma factors VII (FVII), VIIa (FVIIa), and VIII (FVIII); thrombin-antithrombin (TAT) complex; D-dimer; tissue factor pathway inhibitor, and plasminogen activator inhibitor-1 (PAI-1) antigen in patients enrolled in the Stroke Hyperglycemia Insulin Network Effort trial of intensive versus standard glucose control on functional outcome at 3 months after AIS. Changes in biomarkers over time (from baseline ≈12 hours after stroke onset) to 48 hours, and changes in biomarkers between treatment groups, functional outcomes, and their interaction were analyzed by two-way analysis of variance.

RESULTS

A total of 125 patients were included (57 in the intensive treatment group and 68 in the standard treatment group). The overall mean age was 66 years; 42% were women. Changes from baseline to 48 hours in coagulation markers were significantly different between treatment groups for TFPCA (P = 0.02) and PAI-1 (P = .04) and FVIIa (P = .04). Increases in FVIIa and decreases in FVIII were associated with favorable functional outcomes (P = .04 and .04, respectively). In the intensive treatment group, reductions in TFPCA and FVIII and increases in FVIIa were greater in patients with favorable than unfavorable outcomes (P = .02, 0.002, 0.03, respectively). In the standard treatment group, changes in FVII were different by functional outcome (P = .006).

CONCLUSIONS

Intensive glucose control induced greater alterations in coagulation biomarkers than standard treatment, and these were associated with a favorable functional outcome at 3 months after AIS.

Efficacy and Safety of Intravenous rtPA in Ischemic Strokes Due to Small-Vessel Occlusion: Systematic Review and Meta-Analysis

Intravenous recombinant tissue plasminogen activator (iv-rtPA) has been routinely used to treat ischemic stroke for 25 years, following large clinical trials. However, there are few prospective studies on the efficacy and safety of this therapy in strokes attributed to cerebral small vessel disease (SVD). We evaluated functional outcome (modified Rankin scale, mRS) and symptomatic intracerebral hemorrhage (sICH) using all available data on the effects of iv-rtPA in SVD-related ischemic stroke (defined either using neuroimaging, clinical features, or both). Using fixed-effect and random-effects models, we calculated the pooled effect estimates with regard to excellent and favorable outcomes (mRS=0-1 and 0-2 respectively, at 3 months), and the rate of sICH. Twenty-three studies fulfilled the eligibility criteria, 11 of which were comparative, and there were only 3 randomized clinical trials. In adjusted analyses, there was an increased odds of excellent outcome (adjusted OR=1.53, 95% CI: 1.29-1.82, I2: 0%) or favorable outcome (adjusted OR=1.68, 95% CI: 1.31-2.15,I2: 0%) in patients who received iv-rtPA compared with placebo. Across the six studies which reported it, the incidence of sICH was higher in the treatment group (M-H RR = 8.83, 95% CI: 2.76-28.27). The pooled rate of sICH in patients with SVD administered iv-rtPA was only 0.72% (95% CI: 0.12%-1.64%). We conclude that when ischemic stroke attributed to SVD is considered separately, available data on the effects of iv-rtPA therapy are insufficient for the highest level of recommendation, but it seems to be safe. Although further therapeutic trials in SVD-related ischemic stroke appear to be justified, our findings should not prevent its continued use for this group of patients in clinical practice.

Thrombolysis Outcomes in Patients with Diabetes and Previous Stroke: A Meta-Analysis

BACKGROUND

Intravenous tissue-type plasminogen activator (IVtPA) is a proven treatment for acute ischemic stroke; however, diabetes mellitus (DM) and previous cerebral infarction (PCI) were considered relative contraindications for thrombolysis within the 3-4.5 h period.

OBJECTIVE

The study aimed to determine the safety and efficacy of IVtPA among diabetic patients with PCI presenting with acute ischemic stroke.

METHODS

Studies which evaluated the outcome of IVtPA in terms of symptomatic intracerebral hemorrhage (sICH), functional outcome in modified Rankin scale, and death among diabetic patients with PCI presenting with acute ischemic stroke within the 3-4.5 h period were systematically searched until July 2019. Screening and eligibility criteria were applied. Risk of bias was evaluated using the Newcastle-Ottawa Scale. Odds ratios (ORs) with 95% confidence interval (CI) were used to compare measures of treatment effect. Mantel-Haenszel method and random-effects model were also employed.

RESULTS

Four registry-based studies with a total of 44,572 patients were included for quantitative synthesis. Giving IVtPA among DM+/PCI+ patients did not result in significantly increased rate of sICH (OR, 1.09; 95% CI, 0.88, 1.36) compared to No DM+/PCI+ patients. However, there was significantly higher mortality (OR, 1.81; 95% CI, 1.60, 2.06) in the DM+/PCI+ group. Conversely, among those who survived, the DM+/PCI+ patients were more functionally independent at 3 months (OR, 0.76; 95% CI, 0.61, 0.94).

CONCLUSION

Limited evidence suggests that thrombolysis in DM+/PCI+ patients does not result in significantly higher incidence of sICH and may improve functional independence. However, the significantly higher mortality in this group warrants an assessment of the individualized risk-benefit ratio in the use of IVtPA.

Recurrent thrombolysis of a stuttering lacunar infarction captured on serial MRIs

Lacunar strokes account for about a fourth of all ischemic strokes. Pontine infarcts often present with stuttering symptoms, referred to as pontine warning syndrome (PWS). Patients presenting with fluctuating symptoms can appear to have rapidly improving symptoms and thus often go untreated despite the risk of recurrent deficits. MRI carries a higher sensitivity in detecting posterior circulation strokes compared to computed topagraphy, but does not always indicate irreversible injury. Here we present the first description of a stuttering lacune, captured radiographically on serial magnetic resonance imaging (MRI), that was initially averted with the administration of intravenous (IV) tissue plasminogen activator (tPA), only to return a month later and progress on imaging despite re-administration of tPA. During the first admission, our patient had spontaneous resolution of symptoms with complete reversal on restricted diffusion soon after IV tPA administration. On the second admission, the stuttering symptoms returned as did the same pontine lesion. Although his stuttering lesions lasted for several days, and the pontine lesion did ultimately progress to partial infarction on MRI, he was discharged home without neurologic deficits. Our case suggests that tPA may be of benefit in patients with lacunar pontine strokes even if symptoms rapidly improve or resolve.

Factors Associated with Early Recovery after Intravenous Thrombolytic Therapy in Acute Ischemic Stroke

Introduction

In this study, we aimed to identify the factors associated with early neurological improvement (ENI) in acute stroke patients treated with intravenous recombinant tissue plasminogen activator (IV rt-PA), and to determine the association between ENI and outcomes at 3 months after stroke.

Methods

Patients with acute ischemic stroke who were treated with IV rt-PA within 4.5 hours of symptom onset from February 2009 to December 2016 were included in the study at the stroke center of Eskişehir Osmangazi University Medical Faculty. ENI was defined as an improvement in National Institutes of Health Stroke Scale (NIHSS) score of ≥8 points compared to the pretreatment score or an NIHSS score of 0 or 1 at 24 hours after stroke. We assessed the outcomes at 3 months after treatment using the modified Rankin Scale (mRS) score, and mRS scores of 0-1 were defined as 'very good' outcomes.

Results

ENI was observed in 43.9% of 355 patients included in the study. Very good outcome at the 3rd month was detected in 80.1% of the patients with ENI, and in 15.6% of the patients without ENI (p<0.001). Patients with ENI were younger (p=0.025), and had lower NIHSS scores (p=0.027) and higher ASPECT scores (p=0.008) than those without. The ENI group had lower serum glucose levels at the time of admission (p< 0.001). Additionally, the presence of diabetes mellitus, hypertension, and hyperdense artery sign were more frequent in the ENI group (p=0.001, p=0.024, and p<0.001, respectively). Finally, multiple regression analysis showed a significant relationship between serum glucose level, hyperdense artery sign, and ENI.

Conclusion

There is a significant relationship between ENI and very good outcome at 3 months in acute stroke patients who received IV rt-PA. Therefore, the management of factors such as serum glucose level, NIHSS score, ASPECT score and presence of hyperdense artery sign which are related to ENI, and the determination of treatment strategies according to them are important issues for achieving a better outcome in acute ischemic stroke.