Hemoglobin A1c predicts hemorrhagic transformation and poor outcomes after acute anterior stroke

Effect of INR on Outcomes of Endovascular Treatment for Acute Vertebrobasilar Artery Occlusion

Endovascular treatment (EVT) has been proven to be the standard treatment for acute vertebrobasilar artery occlusion (VBAO). This study aimed to analyze the effects of international normalized ratio (INR) indicators on outcomes in patients with acute VBAO treated with EVT. Dynamic data on INR in patients with VBAO who received endovascular treatment (EVT) at 65 stroke centers in China were retrospectively enrolled. Outcome measures included the modified Rankin Scale (mRS) score at 90 days and 1 year and symptomatic intracranial hemorrhage (sICH). The associations between elevated INR (INR > 1.1), INR variability (time-weighted variance of INR changes), and various clinical outcomes were analyzed in all patients and subgroups stratified by oral anticoagulation (OAC) by mixed logistic regression analysis. A total of 1825 patients met the study criteria, of which 1384 had normal INR and 441 had elevated INR. Multivariate analysis showed that elevated INR was significantly associated with poor functional outcomes (mRS 4-6) at 90 days (odds ratio [OR] 1.36, 95% confidence interval [CI] 1.08-1.72) and 1 year (OR 1.32, 95% CI 1.05-1.66), but was not associated with an increased risk of sICH (OR 1.00, 95% CI 0.83-1.20). Similar associations exist between INR variability and poor functional outcomes at 90 days (OR 2.17, 95% CI 1.09-4.30), 1 year (OR 2.28, 95% CI 1.16-4.46), and sICH (OR 1.11, 95% CI 0.93-1.33). Subgroup analyses further revealed that elevated INR and INR variability remained associated with poor functional outcomes in patients not receiving oral anticoagulation (OAC) therapy, while no significant associations were observed in OAC-treated patients, regardless of whether they were on warfarin or direct oral anticoagulants. Elevated INR and INR variability in VBAO patients treated with EVT were associated with poor functional outcomes. The mechanism underlying the association between elevated INR and poor functional outcomes might be attributed to the fact that elevated INR indirectly reflects the burden of comorbidities, which could independently worsen outcomes. These findings underscore the importance of a comprehensive and dynamic evaluation of INR levels in the management of VBAO patients receiving EVT, providing valuable insights for optimizing patient outcomes.

Higher blood glucose is associated with the severity of hemorrhagic transformation after endovascular therapy for stroke

OBJECTIVES

Hyperglycemia is associated with poor outcome in large vessel occlusion (LVO) stroke, with mechanism for this effect unknown.

MATERIALS AND METHODS

We used our prospective, multicenter, observational study, Blood Pressure After Endovascular Stroke Therapy (BEST), of anterior circulation LVO stroke undergoing endovascular therapy (EVT) from 11/2017-7/2018 to determine association between increasing blood glucose (BG) and intracerebral hemorrhage (ICH). Our primary outcome was degree of ICH, classified as none, asymptomatic ICH, or symptomatic ICH (≥4-point increase in National Institutes of Health Stroke Scale [NIHSS] at 24 h with any hemorrhage on imaging). Secondary outcomes included 24 h NIHSS, early neurologic recovery (ENR, NIHSS 0-1 or NIHSS reduction by ≥8 within 24 h), and 90-day modified Rankin Scale (mRS) using univariate and multivariable regression.

RESULTS

Of 485 enrolled patients, increasing BG was associated with increasing severity of ICH (adjusted OR, aOR 1.06, 95 % CI 1.02-1.1, p < 0.001), higher 24 h NIHSS (aOR 1.22, 95 % CI 1.11-1.34, p < 0.001), ENR (aOR 0.90, 95 % CI 0.82-1.00, p < 0.002), and 90-day mRS (aOR 1.06, 95 % CI 1.03-1.09, p < 0.001) when adjusted for age, presenting NIHSS, ASPECTS, 24-hour peak systolic blood pressure, time from last known well, and successful recanalization.

CONCLUSIONS

In the BEST study, increasing BG was associated with greater odds of increasing ICH severity. Further study is warranted to determine whether treatment of will decrease ICH severity following EVT.

Association of large core middle cerebral artery stroke and hemorrhagic transformation with hospitalization outcomes

Historically, investigators have not differentiated between patients with and without hemorrhagic transformation (HT) in large core ischemic stroke at risk for life-threatening mass effect (LTME) from cerebral edema. Our objective was to determine whether LTME occurs faster in those with HT compared to those without. We conducted a two-center retrospective study of patients with ≥ 1/2 MCA territory infarct between 2006 and 2021. We tested the association of time-to-LTME and HT subtype (parenchymal, petechial) using Cox regression, controlling for age, mean arterial pressure, glucose, tissue plasminogen activator, mechanical thrombectomy, National Institute of Health Stroke Scale, antiplatelets, anticoagulation, temperature, and stroke side. Secondary and exploratory outcomes included mass effect-related death, all-cause death, disposition, and decompressive hemicraniectomy. Of 840 patients, 358 (42.6%) had no HT, 403 (48.0%) patients had petechial HT, and 79 (9.4%) patients had parenchymal HT. LTME occurred in 317 (37.7%) and 100 (11.9%) had mass effect-related deaths. Parenchymal (HR 8.24, 95% CI 5.46-12.42, p < 0.01) and petechial HT (HR 2.47, 95% CI 1.92-3.17, p < 0.01) were significantly associated with time-to-LTME and mass effect-related death. Understanding different risk factors and sequelae of mass effect with and without HT is critical for informed clinical decisions.

Prediction of Death in Intracerebral Hemorrhage Patients After Minimally Invasive Surgery by Vital Signs and Blood Glucose

OBJECTIVE

This study examined the impact of vital signs and blood glucose levels on the long-term prognosis of intracerebral hemorrhage (ICH) patients treated with minimally invasive surgery (MIS).

METHODS

The patients diagnosed with ICH and treated with MIS within 24 hours of admission at the ∗∗ Hospital between January 2020 and October 2021 were included. The relationship between a range of indicators, including vital signs, blood glucose levels, and patient mortality at discharge and 3 or 12 months postdischarge were analyzed.

RESULTS

A total of 195 consecutive patients were included, of which 16 patients passed away during hospitalization, 29 and 34 within 3 and 12 months postdischarge, respectively. The multivariate analysis revealed that hospital death positively correlated with age ≥66.50 years, fasting blood glucose ≥8.25 mmol/L on the third day after MIS, systolic blood pressure ≥166.00 mmHg on the third day, and heart rate ≥89.50 beats/min at discharge (area under the curve [AUC] = 0.927). Death at 3 months positively correlated with male sex, blood glucose before dinner ≥8.15 mmol/L on the second day after MIS, body temperature ≥36.95°C at discharge, and heart rate ≥89.50 beats/minute at discharge (AUC = 0.810). Death at 12 months positively correlated with age ≥61.50 years, body temperature ≥36.95°C at discharge, and heart rate ≥92.50 beats/min on the third day after MIS (AUC = 0.824).

CONCLUSIONS

The prognosis of ICH patients after MIS is closely related to their vital signs and blood glucose levels at various stages of hospitalization.

Biochemical, biomechanical and imaging biomarkers of ischemic stroke: Time for integrative thinking

Stroke is one of the leading causes of adult disability affecting millions of people worldwide. Post-stroke cognitive and motor impairments diminish quality of life and functional independence. There is an increased risk of having a second stroke and developing secondary conditions with long-term social and economic impacts. With increasing number of stroke incidents, shortage of medical professionals and limited budgets, health services are struggling to provide a care that can break the vicious cycle of stroke. Effective post-stroke recovery hinges on holistic, integrative and personalized care starting from improved diagnosis and treatment in clinics to continuous rehabilitation and support in the community. To improve stroke care pathways, there have been growing efforts in discovering biomarkers that can provide valuable insights into the neural, physiological and biomechanical consequences of stroke and how patients respond to new interventions. In this review paper, we aim to summarize recent biomarker discovery research focusing on three modalities (brain imaging, blood sampling and gait assessments), look at some established and forthcoming biomarkers, and discuss their usefulness and complementarity within the context of comprehensive stroke care. We also emphasize the importance of biomarker guided personalized interventions to enhance stroke treatment and post-stroke recovery.

Roles of Bilirubin in Hemorrhagic Transformation of Different Types and Severity

BACKGROUND

Hemorrhagic transformation (HT) is a severe complication in patients with acute ischemic stroke (AIS). This study was performed to explore and validate the relation between bilirubin levels and spontaneous HT (sHT) and HT after mechanical thrombectomy (tHT).

METHODS

The study population consisted of 408 consecutive AIS patients with HT and age- and sex-matched patients without HT. All patients were divided into quartiles according to total bilirubin (TBIL) level. HT was classified as hemorrhagic infarction (HI) and parenchymal hematoma (PH) based on radiographic data.

RESULTS

In this study, the baseline TBIL levels were significantly higher in the HT than non-HT patients in both cohorts (p < 0.001). Furthermore, the severity of HT increased with increasing TBIL levels (p < 0.001) in sHT and tHT cohorts. The highest quartile of TBIL was associated with HT in sHT and tHT cohorts (sHT cohort: OR = 3.924 (2.051-7.505), p < 0.001; tHT cohort: OR = 3.557 (1.662-7.611), p = 0.006).

CONCLUSIONS

Our results suggest that an increased TBIL is associated with a high risk of patients with sHT and tHT, and that TBIL is more suitable as a predictor for sHT than tHT. These findings may help to identify patients susceptible to different types and severity of HT.

Prognostic significance of international normalised ratio and prothrombin time in Chinese acute ischaemic stroke patients

BACKGROUND

We investigated the association between international normalised ratio (INR) and prothrombin time (PT) levels on hospital admission and in-hospital outcomes in acute ischaemic stroke (AIS) patients.

METHODS

A total of 3175 AIS patients enrolled from December 2013 to May 2014 across 22 hospitals in Suzhou city were included. We divided patients into four groups according to their level of admission INR: (<0.92), Q2 (0.92-0.98), Q3 (0.98-1.04) and Q4 (≥1.04) and PT. Logistic regression models were used to estimate the effect of INR and PT on death or major disability (modified Rankin Scale score (mRS)>3), death and major disability (mRS scores 4-5) separately on discharge in AIS patients.

RESULTS

Having an INR level in the highest quartile (Q4) was associated with an increased risk of death or major disability (OR 1.69; 95% CI 1.23 to 2.31; P-trend=0.001), death (OR, 2.64; 95% CI 1.12 to 6.19; P-trend=0.002) and major disability on discharge (OR, 1.56; 95% CI 1.13 to 2.15; P-trend=0.008) in comparison to Q1 after adjusting for potential covariates. Moreover, in multivariable logistic regression models, having a PT level in the highest quartile also significantly increased the risk of death (OR, 2.38; 95% CI 1.06 to 5.32; P-trend=0.006) but not death or major disability (P-trend=0.240), major disability (P-trend=0.606) on discharge.

CONCLUSIONS

High INR at admission was independently associated with death or major disability, death and major disability at hospital discharge in AIS patients and increased PT was also associated with death at hospital discharge.

High glycemic albumin representing prestroke glycemic variability is associated with hemorrhagic transformation in patients receiving intravenous thrombolysis

We evaluated the impact of prestroke glycemic variability estimated by glycated albumin (GA) on symptomatic hemorrhagic transformation (SHT) in patients with intravenous thrombolysis (IVT). Using a multicenter database, we consecutively enrolled acute ischemic stroke patients receiving IVT. A total of 378 patients were included in this study. Higher GA was defined as GA ≥ 16.0%. The primary outcome measure was SHT. Multivariate regression analysis and a receiver operating characteristic curve were used to assess risks and predictive ability for SHT. Among the 378 patients who were enrolled in this study, 27 patients (7.1%) had SHT as defined by the Safe Implementation of Thrombolysis in Stroke-Monitoring Study (SHT_SITS). The rate of SHT_SITS was higher in the higher GA group than in the lower GA group (18.0% vs. 1.6%, p < 0.001). A higher GA level (GA ≥ 16.0%) significantly increased the risk of SHT_SITS (adjusted odds ratio [OR], [95% confidence interval, CI], 12.57 [3.08–41.54]) in the logistic regression analysis. The predictive ability of the GA level for SHT_SITS was good (AUC [95% CI]: 0.83 [0.77–0.90], p < 0.001), and the cutoff value of GA in SHT was 16.3%. GA was a reliable predictor of SHT after IVT in acute ischemic stroke in this study.

Association Between Raised HbA1c Levels and Hemorrhagic Transformation in Patients With Ischemic Stroke

Background Glycated hemoglobin (HbA1c) is a commonly used indicator of glycemic control in diabetes mellitus. Uncontrolled diabetes can lead to cardiovascular complications. Ischemic strokes are often complicated by hemorrhagic transformation, which is the conversion of an infarcted area into an area of hemorrhage. The purpose of this study is to determine the association of raised HbA1c levels with the occurrence of hemorrhagic transformation in ischemic stroke. Methods This is a prospective, single-center cohort study of patients admitted to the Neurology and Medicine wards between June 1 and November 30, 2019. Inclusion criteria included adult patients who were admitted with acute ischemic stroke and had been tested for HbA1c on presentation. There were 110 ischemic stroke patients enrolled in our database. An HbA1c level >53 mmol/mol was considered raised. A comparison was done between the group with raised HbA1c levels and the group with target levels of HbA1c for the occurrence of hemorrhagic transformation. Brain imaging was used to diagnose hemorrhagic transformation. Results Out of 110 study participants with ischemic stroke, 70 (63.6%) patients had a history of prior known diabetes. The mean HbA1c levels were 7.44 ± 1.79%. A total of 77% of diabetic patients had raised HbA1c levels (>7%). Hemorrhagic transformation was seen in 21 (19.1%) patients, of whom only 38% (n=8) had raised HbA1c levels. The association between raised HbA1c and hemorrhagic transformation was not found to be statistically significant (p = 0.225). Conclusion In this study of patients with ischemic stroke, raised HbA1c levels were not found to be associated with hemorrhagic transformation. There is a need for larger scale studies to find out the cause and mechanism of hemorrhagic transformation in ischemic stroke.

Hemorrhagic Transformation in Ischemic Stroke and the Role of Inflammation

Hemorrhagic transformation (HT) is a common complication in patients with acute ischemic stroke. It occurs when peripheral blood extravasates across a disrupted blood brain barrier (BBB) into the brain following ischemic stroke. Preventing HT is important as it worsens stroke outcome and increases mortality. Factors associated with increased risk of HT include stroke severity, reperfusion therapy (thrombolysis and thrombectomy), hypertension, hyperglycemia, and age. Inflammation and the immune system are important contributors to BBB disruption and HT and are associated with many of the risk factors for HT. In this review, we present the relationship of inflammation and immune activation to HT in the context of reperfusion therapy, hypertension, hyperglycemia, and age. Differences in inflammatory pathways relating to HT are discussed. The role of inflammation to stratify the risk of HT and therapies targeting the immune system to reduce the risk of HT are presented.

Glycated Hemoglobin as a Marker for Predicting Outcomes of Patients With Stroke (Ischemic and Hemorrhagic): A Systematic Review and Meta-Analysis

Background: Glycated hemoglobin (HbA1c) has emerged as a useful biochemical marker reflecting the average glycemic control over the last 3 months, and the values are not affected by short-term transient changes in blood glucose levels. However, its prognostic value in the acute neurological conditions such as stroke is still not well-established. The present meta-analysis was conducted to assess the relationship of HbA1c with outcomes such as mortality, early neurological complications, and functional dependence in stroke patients.

Methods: A systematic search was conducted for the PubMed, Scopus, and Google Scholar databases. Studies, either retrospective or prospective in design that examined the relationship between HbA1c with outcomes of interest and presented the strength of association in the form of adjusted odds ratio/hazard ratios were included in the review. Statistical analysis was done using STATA version 13.0.

Results: A total of 22 studies (15 studies on acute ischemic stroke and seven studies on hemorrhagic stroke) were included in the meta-analysis. For patients with acute ischemic stroke, each unit increase in HbA1c was found to be associated with an increased risk of mortality within 1 year, increased risk of poor functional outcome at 3 months, and an increased risk of symptomatic intracranial hemorrhage (sICH) within 24 h of admission. In those with HbA1c ≥ 6.5%, there was an increased risk of mortality within 1 year of admission, increased risk of poor functional outcomes at 3 and 12 months as well as an increased risk of symptomatic intracranial hemorrhage (sICH) within 24 h of admission. In patients with hemorrhagic stroke, each unit increase in HbA1c was found to be associated with increased risk of poor functional outcome within the first 3 months from the time of admission for stroke. In those with HbA1c ≥ 6.5%, there was an increased risk of poor functional outcome at 12 months.

Conclusions: The findings indicate that glycated hemoglobin (HbA1c) could serve as a useful marker to predict the outcomes in patients with stroke and aid in the implementation of adequate preventive management strategies at the earliest.

Hemostasis functions are associated with hemorrhagic transformation in non-atrial fibrillation patients: a case-control study

Background

Hemorrhagic transformation (HT) is a serious neurological complication of acute ischemic stroke (AIS) after revascularization. The majority of AIS patients do not have atrial fibrillation (AF) which could also develop into HT. In this study, we aimed to explore whether hemostasis parameters are risk factors of HT in non-AF patients.

Methods

We consecutively enrolled 285 AIS patients with HT. Meanwhile, age- and sex-matched 285 AIS patients without HT were included. The diagnosis of HT was determined by brain CT or MRI during hospitalization. All patients were divided into two subgroups based on the presence of AF and explore the differences between the two subgroups. Blood samples were obtained within 24 h of admission, and all patients were evenly classified into three tertiles according to platelet counts (PLT) levels.

Results

In this study, we found the first PLT tertile (OR = 3.509, 95%CI = 1.268–9.711, P = 0.016) was independently associated with HT in non-AF patients, taking the third tertile as a reference. Meanwhile, we also found mean platelet volume (MPV) (OR = 0.605, 95%CI = 0.455–0.805, P = 0.001) and fibrinogen (FIB) (OR = 1.928, 95%CI = 1.346–2.760, P < 0.001) were significantly associated with HT in non-AF patients. But in AF patients, hemostasis parameters showed no significant difference. Meanwhile, we found the MPV (OR = 1.314, 95%CI = 1.032–1.675, P = 0.027) and FIB (OR = 1.298, 95%CI = 1.047–1.610, P = 0.018) were significantly associated with long-term outcomes in non-AF HT patients.

Conclusions

Low PLT, low MPV, and high FIB levels were independently associated with HT in non-AF patients. Additionally, MPV and FIB levels were significantly associated with unfavorable long-term outcomes in non-AF HT patients. Our study showed that hemostasis functions at admission may be beneficial for clinicians to recognize patients with a high risk of HT at an early stage and improve unfavorable long-term outcomes in non-AF patients.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12883-021-02065-3.

AST to ALT ratio and risk of hemorrhagic transformation in patients with acute ischemic stroke

BACKGROUND

Hemorrhagic transformation (HT) is a common complication of ischemic stroke. We performed this study to determine whether aspartate aminotransferase (AST) to alanine aminotransferase (ALT) ratio (AAR) was related to HT, as well as compare the predictive values of AAR, ALT and AST for HT in patients with ischemic stroke.

METHODS

We included ischemic stroke patients within 7 days of onset. HT was identified by a follow-up imaging examination. Univariate and multivariate logistic regression models were performed to assess the association between AAR and HT. Net reclassification index (NRI) was calculated to assess the ability of AAR, AST and ALT to reclassify risks of HT.

RESULTS

A total of 2042 (median age: 69 years; 63.2% males) patients were included in this study, of whom 232 (11.4%) were identified as HT. The receiver-operating characteristic curve analysis showed that the optimal cut-off value for AAR to predict HT was 1.22. Higher AAR (≥1.22) was an independent predictor associated with HT (OR 1.44, 95%CI 1.06-1.97, P = 0.02) after adjusting for covariates. A U-shaped dose-effect relationship was found between AAR level and HT in logistic regression model with restricted cubic splines. In addition, adding AAR to a model containing conventional risk factors significantly improved predictive power for HT (NRI: 15.4%, P = 0.027), but not for ALT (NRI: 10.3%, P = 0.141) or AST (NRI: 8.3%, P = 0.237).

CONCLUSIONS

Higher AAR was associated with an increased risk of HT after ischemic stroke. In addition, AAR might be a better biomarker for predicting HT than ALT or AST.

Predictors of hemorrhagic transformation after acute ischemic stroke based on the experts' opinion

BACKGROUND

Hemorrhagic transformation (HT) is a common complication after ischemic stroke. It may be associated to poor outcomes. Some predictors of HT have been previously identified, but there remain controversies.

OBJECTIVE

To describe the risk factors for HT more frequently reported by a panel of experts surveyed for this project.

METHODS

We sent a standard questionnaire by e-mail to specialists in Vascular Neurology from 2014 to 2018. Forty-five specialists were contacted and 20 of them responded to the invitation. Predictors cited by three or more specialists were included in a table and ranked by the frequency in which they appeared. A review of the literature looking for published predictive scores of HT was performed, comparing to the answers received.

RESULTS

The 20 responding specialists cited 23 different risk factors for HT. The most frequent factors in the order of citation were the volume of ischemia, previous use of antithrombotic medication, neurological severity, age, hyperglycemia at presentation, hypertension on admission, and cardioembolism. Most variables were also found in previously published predictive scores, but they were reported by the authors with divergences of frequency.

CONCLUSION

Although many studies have evaluated HT in patients with acute ischemic stroke, the published risk factors were neither uniform nor in agreement with those cited by the stroke specialists. These findings may be helpful to build a score that can be tested with the goal of improving the prediction of HT.

Diabetic Stroke Promotes a Sexually Dimorphic Expansion of T Cells

We recently reported that diabetes negates the cerebrovascular protection typically seen in adult female rats resulting in cognitive impairment, which is worsened by increased parenchymal bleeding and edema after ischemic stroke. Although women experience more severe diabetes and suffer from a higher rate of diabetic complications, including stroke and cognitive impairment, underlying mechanisms contributing to sex differences are limited. Emerging evidence suggests interleukin (IL)-17 contributes to cerebrovascular pathologies: (1) high salt diet-mediated expansion of IL-17-producing T cells (Th17) in the gut microbiome promotes cerebrovascular dysfunction and cognitive impairment in male mice, (2) increased IL-17-producing γδTCR cells exacerbates stroke injury in male mice, and (3) IL-17 promotes rupture of cerebral aneurysms in female mice. Based on these premises, we investigated the potential involvement of IL-17-producing inflammatory cells in cerebrovascular dysfunction and post-stroke vascular injury in diabetes by measuring intestinal, circulating, or cerebral T cell profiles as well as in plasma IL-17 in both sexes. Cell suspensions prepared from naive or stroked (3 days after stroke) diabetic and control rats were analyzed by flow cytometry, and IL-17 levels were measured in plasma using ELISA. Diabetes deferentially promoted the expansion of cerebral Th17 cells in females. In response to stroke, diabetes had a sexually dimorphic effect on the expansion of numerous T cell profiles. These results suggest that a better understanding of the role of IL-17-producing cells in diabetes may identify potential avenues in which the molecular mechanisms contributing to these sex differences can be further elucidated.

Low triiodothyronine syndrome is associated with hemorrhagic transformation in patients with acute ischaemic stroke

Hemorrhagic transformation (HT) is a severe complication occurring in acute ischemic stroke (AIS) patients. We explored the association between low triiodothyronine (T3) syndrome and HT in AIS patients. A total of 208 consecutive participants with HT and 208 age- and sex-matched stroke patients without HT were enrolled in this study. HT was diagnosed by follow-up imaging assessment, and was radiologically classified as hemorrhagic infarction (HI) type 1 or 2 or parenchymal hematoma (PH) type 1 or 2. HT was also classified into asymptomatic or symptomatic. The incidence of low T3 syndrome was significantly higher among patients who developed HT than among those without HT. Moreover, the more severe the HT, the lower the detected T3 levels. Multivariate-adjusted binary logistic regression showed that low T3 syndrome was an independent risk factor for HT and symptomatic HT in AIS patients. Low T3 syndrome was also significantly associated with a higher risk of PH, but not with the risk of HI. Thus, low T3 syndrome was independently associated with the risk of HT, symptomatic HT, and severe HT (PH) in AIS patients, which suggests monitoring T3 could be a useful means of preventing HT in patients with ischemic stroke.