Impact of Cerebral Microbleeds in Stroke Patients with Atrial Fibrillation.

OBJECTIVES: Cerebral microbleeds are associated with the risks of ischemic stroke and intracranial hemorrhage, causing clinical dilemmas for antithrombotic treatment decisions. We aimed to evaluate the risks of intracranial hemorrhage and ischemic stroke associated with microbleeds in patients with atrial fibrillation treated with vitamin K antagonists, direct oral anticoagulants, antiplatelets, and combination therapy (i.e. concurrent oral anticoagulant and antiplatelet). METHODS: We included patients with documented atrial fibrillation from the pooled individual patient data analysis by the Microbleeds International Collaborative Network. Risks of subsequent intracranial hemorrhage and ischemic stroke were compared between patients with and without microbleeds, stratified by antithrombotic use. RESULTS: A total of 7,839 patients were included. The presence of microbleeds was associated with an increased relative risk of intracranial hemorrhage (adjusted hazard ratio [aHR] = 2.74, 95% confidence interval = 1.76-4.26) and ischemic stroke (aHR = 1.29, 95% confidence interval = 1.04-1.59). For the entire cohort, the absolute incidence of ischemic stroke was higher than intracranial hemorrhage regardless of microbleed burden. However, for the subgroup of patients taking combination of anticoagulant and antiplatelet therapy, the absolute risk of intracranial hemorrhage exceeded that of ischemic stroke in those with 2 to 4 microbleeds (25 vs 12 per 1,000 patient-years) and ≥ 11 microbleeds (94 vs 48 per 1,000 patient-years). INTERPRETATION: Patients with atrial fibrillation and high burden of microbleeds receiving combination therapy have a tendency of higher rate of intracranial hemorrhage than ischemic stroke, with potential for net harm. Further studies are needed to help optimize stroke preventive strategies in this high-risk group. ANN NEUROL 2023;94:61-74.

Preventing post-stroke dementia. The MARCH Trial. Protocol and statistical analysis plan of a randomized clinical trial testing the safety and efficacy of Maraviroc in post-stroke cognitive impairment.

Background: Current evidence suggest that 25%-33% of stroke-survivors develop post-stroke cognitive impairment (PSCI). The licensed drug Maraviroc, a CCR5-antagonist, is postulated to act via a neuroprotective mechanism that may offer the potential of preventing progression to vascular dementia. Our hypothesis: Maraviroc may have the potential to augment learning skills and cognitive performance by affecting synaptic plasticity, along with neuro-inflammatory modulation in patients with cerebral small vessel disease (SVD) and PSCI. Design: MARCH is a multi-center, double-blind randomized-control Phase-II trial of Maraviroc 150 or 600 mg/day versus placebo for 12-months in five stroke centers in Israel. Included are patients diagnosed with recent (1-24 months) subcortical stroke who experience mild PSCI and have evidence of white matter lesions and SVD on neuroimaging. Outcomes: Primary outcomes: 1. Change in cognitive scores. 2. Drug related adverse events. Secondary outcomes: change in functional and affective scores, MRI-derived measures, inflammatory markers, carotid atherosclerosis, cerebrospinal-fluid biomarkers in a sub-study. A sample size of 60 in each treatment group and 30 in the placebo group (total - 150 participants) provides 80% power between the treatment and the placebo groups. Conclusions: The results of this work could lead to a novel, readily available, therapeutic avenue to reduce PSCI, and possibly other pathologies. This study will test safety and effectiveness of Maraviroc in limiting cognitive deterioration and/or post stroke cognitive impairment in patients with cerebral small vessel disease. Schedule: First-patient first-visit was May 2021. Recruitment to complete in 2023, follow-up to complete in 2024.

Cerebral microbleeds and stroke risk after ischaemic stroke or transient ischaemic attack: a pooled analysis of individual patient data from cohort studies.

BACKGROUND: Cerebral microbleeds are a neuroimaging biomarker of stroke risk. A crucial clinical question is whether cerebral microbleeds indicate patients with recent ischaemic stroke or transient ischaemic attack in whom the rate of future intracranial haemorrhage is likely to exceed that of recurrent ischaemic stroke when treated with antithrombotic drugs. We therefore aimed to establish whether a large burden of cerebral microbleeds or particular anatomical patterns of cerebral microbleeds can identify ischaemic stroke or transient ischaemic attack patients at higher absolute risk of intracranial haemorrhage than ischaemic stroke. METHODS: We did a pooled analysis of individual patient data from cohort studies in adults with recent ischaemic stroke or transient ischaemic attack. Cohorts were eligible for inclusion if they prospectively recruited adult participants with ischaemic stroke or transient ischaemic attack; included at least 50 participants; collected data on stroke events over at least 3 months follow-up; used an appropriate MRI sequence that is sensitive to magnetic susceptibility; and documented the number and anatomical distribution of cerebral microbleeds reliably using consensus criteria and validated scales. Our prespecified primary outcomes were a composite of any symptomatic intracranial haemorrhage or ischaemic stroke, symptomatic intracranial haemorrhage, and symptomatic ischaemic stroke. We registered this study with the PROSPERO international prospective register of systematic reviews, number CRD42016036602. FINDINGS: Between Jan 1, 1996, and Dec 1, 2018, we identified 344 studies. After exclusions for ineligibility or declined requests for inclusion, 20 322 patients from 38 cohorts (over 35 225 patient-years of follow-up; median 1·34 years [IQR 0·19-2·44]) were included in our analyses. The adjusted hazard ratio [aHR] comparing patients with cerebral microbleeds to those without was 1·35 (95% CI 1·20-1·50) for the composite outcome of intracranial haemorrhage and ischaemic stroke; 2·45 (1·82-3·29) for intracranial haemorrhage and 1·23 (1·08-1·40) for ischaemic stroke. The aHR increased with increasing cerebral microbleed burden for intracranial haemorrhage but this effect was less marked for ischaemic stroke (for five or more cerebral microbleeds, aHR 4·55 [95% CI 3·08-6·72] for intracranial haemorrhage vs 1·47 [1·19-1·80] for ischaemic stroke; for ten or more cerebral microbleeds, aHR 5·52 [3·36-9·05] vs 1·43 [1·07-1·91]; and for ≥20 cerebral microbleeds, aHR 8·61 [4·69-15·81] vs 1·86 [1·23-1·82]). However, irrespective of cerebral microbleed anatomical distribution or burden, the rate of ischaemic stroke exceeded that of intracranial haemorrhage (for ten or more cerebral microbleeds, 64 ischaemic strokes [95% CI 48-84] per 1000 patient-years vs 27 intracranial haemorrhages [17-41] per 1000 patient-years; and for ≥20 cerebral microbleeds, 73 ischaemic strokes [46-108] per 1000 patient-years vs 39 intracranial haemorrhages [21-67] per 1000 patient-years). INTERPRETATION: In patients with recent ischaemic stroke or transient ischaemic attack, cerebral microbleeds are associated with a greater relative hazard (aHR) for subsequent intracranial haemorrhage than for ischaemic stroke, but the absolute risk of ischaemic stroke is higher than that of intracranial haemorrhage, regardless of cerebral microbleed presence, antomical distribution, or burden. FUNDING: British Heart Foundation and UK Stroke Association.

The Implication of Combat Stress and PTSD Trajectories in Metabolic Syndrome and Elevated C-Reactive Protein Levels: A Longitudinal Study.

OBJECTIVE: This study sheds light on the importance of long-term follow-up of trauma survivors, posttraumatic stress disorder (PTSD) trajectories, and early detection of health risk factors in trauma survivors. The present study prospectively assessed the following over 23 years: (1) the association of psychological and physiologic stress during captivity with elevated C-reactive protein (CRP) levels and metabolic syndrome (MetS), which includes hypertension; elevated levels of insulin, triglycerides, and fasting glucose; decreased levels of high-density lipoprotein cholesterol; and obesity and (2) the implication of PTSD trajectories in elevated CRP levels and MetS. METHODS: Measurements were taken in 1991, 2003, 2008, and 2015. Participants were 116 Israeli combat veterans of the 1973 Yom Kippur War (of these, 101 were former prisoners of war [ex-POWs] and 15 were comparable controls). The medical assessments relevant for this study were body mass index, fasting blood glucose levels, and diabetes, blood pressure or a diagnosis of hypertension, high-density lipoprotein cholesterol and triglyceride levels, and medication intake. In addition, the PTSD Inventory was used to assess PTSD symptoms and trajectories over time according to DSM-IV-TR PTSD criteria. RESULTS: Captivity-in particular, the captivity stressors of weight loss, physical suffering, psychological suffering, and humiliation-was implicated in both elevated CRP levels and MetS, significantly so with elevated CRP levels (P = .01, R² = 0.33). Captivity-induced PTSD, in particular chronic and delayed PTSD trajectories, was associated with elevated CRP levels and MetS, significantly so for MetS (P = .05). CONCLUSIONS: Monitoring inflammation using markers like CRP level in trauma survivors can be beneficial, particularly if PTSD is chronic or delayed. Clinicians treating trauma survivors should raise awareness of the importance of such measures in light of long-term health vulnerabilities.

Post-stroke dementia - a comprehensive review.

Post-stroke dementia (PSD) or post-stroke cognitive impairment (PSCI) may affect up to one third of stroke survivors. Various definitions of PSCI and PSD have been described. We propose PSD as a label for any dementia following stroke in temporal relation. Various tools are available to screen and assess cognition, with few PSD-specific instruments. Choice will depend on purpose of assessment, with differing instruments needed for brief screening (e.g., Montreal Cognitive Assessment) or diagnostic formulation (e.g., NINDS VCI battery). A comprehensive evaluation should include assessment of pre-stroke cognition (e.g., using Informant Questionnaire for Cognitive Decline in the Elderly), mood (e.g., using Hospital Anxiety and Depression Scale), and functional consequences of cognitive impairments (e.g., using modified Rankin Scale). A large number of biomarkers for PSD, including indicators for genetic polymorphisms, biomarkers in the cerebrospinal fluid and in the serum, inflammatory mediators, and peripheral microRNA profiles have been proposed. Currently, no specific biomarkers have been proven to robustly discriminate vulnerable patients ('at risk brains') from those with better prognosis or to discriminate Alzheimer's disease dementia from PSD. Further, neuroimaging is an important diagnostic tool in PSD. The role of computerized tomography is limited to demonstrating type and location of the underlying primary lesion and indicating atrophy and severe white matter changes. Magnetic resonance imaging is the key neuroimaging modality and has high sensitivity and specificity for detecting pathological changes, including small vessel disease. Advanced multi-modal imaging includes diffusion tensor imaging for fiber tracking, by which changes in networks can be detected. Quantitative imaging of cerebral blood flow and metabolism by positron emission tomography can differentiate between vascular dementia and degenerative dementia and show the interaction between vascular and metabolic changes. Additionally, inflammatory changes after ischemia in the brain can be detected, which may play a role together with amyloid deposition in the development of PSD. Prevention of PSD can be achieved by prevention of stroke. As treatment strategies to inhibit the development and mitigate the course of PSD, lowering of blood pressure, statins, neuroprotective drugs, and anti-inflammatory agents have all been studied without convincing evidence of efficacy. Lifestyle interventions, physical activity, and cognitive training have been recently tested, but large controlled trials are still missing.

Depressive symptoms following stroke and transient ischemic attack: is it time for a more intensive treatment approach? results from the TABASCO cohort study.

OBJECTIVE: To examine whether depressive symptoms after a stroke or a transient ischemic attack (TIA) increase the risk of cognitive impairment and functional deterioration at 2-year follow-up. METHODS: Participants were survivors of first-ever, mild-to-moderate ischemic stroke or TIA from the TABASCO prospective cohort study who underwent 3T magnetic resonance imaging and were examined by a multiprofessional team 6, 12, and 24 months after the event using direct interviews, depression scales, and neurologic, neuropsychological, and functional evaluations. The main outcome was the development of cognitive impairment, either mild cognitive impairment (MCI) or dementia. MCI was diagnosed by a decline on at least 1 cognitive domain (≥ 1.5 SD) of the Montreal Cognitive Assessment score and/or on the computerized neuropsychological battery, as compared with age- and education-matched published norms. Dementia was diagnosed by a consensus forum that included senior neurologists specializing in memory disorders and a neuropsychologist. RESULTS: Data were obtained from 306 consecutive eligible patients (mean age: 67.1 ± 10.0 years) who were admitted to the department of emergency medicine at the Tel Aviv Medical Center from April 1, 2008, to December 1, 2011, within 72 hours from onset of symptoms of TIA or stroke. Of these patients, 51 (16.7%) developed cognitive impairment during a 2-year follow-up. Multivariate regression analysis showed that a Geriatric Depression Scale (GDS) score ≥ 6 at admission and at 6 months after the event was a significant independent marker of cognitive impairment 2 years after the stroke/TIA (OR = 3.62, 95% CI, 1.01-13.00; OR = 3.68, 95% CI, 1.03-13.21, respectively). A higher GDS score at 6 months was also related to a worse functional outcome (P < .001). CONCLUSIONS: Our results support depression screening among stroke and TIA survivors as a tool to identify patients who are prone to have a worse cognitive and functional outcome. These patients may benefit from closer medical surveillance and a more intensive treatment approach. TRIAL REGISTRATION: ClinicalTrials.gov identifier: NCT01926691.

Cognitive decline after stroke: relation to inflammatory biomarkers and hippocampal volume.

BACKGROUND AND PURPOSE: Inflammation may contribute to cognitive impairment after stroke. Inflammatory markers are associated with hippocampal atrophy. We tested whether markers of inflammation, erythrocyte sedimentation rate (ESR), and serum levels of C-reactive protein are associated with reduced hippocampal volume and poor cognitive performance among stroke survivors. METHODS: We analyzed 368 consecutive cases from our prospective study of first-ever mild-moderate stroke patients. MRI, cognitive tests, and inflammatory markers were determined. Patients were reevaluated 6 and 12 months after the event. RESULTS: ESR remained unchanged in follow-up examinations, suggesting a chronic inflammation background in some patients. Higher levels of C-reactive protein and ESR were associated with worse performance in cognitive tests, particularly memory scores. This association was maintained for ESR (but not C-reactive protein) after adjustment for confounders (P=0.002). Patients with smaller hippocampi had inferior cognitive results. Moreover, in a multivariate regression model, higher ESR values (but not C-reactive protein) were related to reduced hippocampal volume (P=0.049). CONCLUSIONS: This report shows a strong relationship between ESR and hippocampal volume, as well as with cognitive performance among poststroke patients. This could plausibly relate to incipient cognitive decline via hippocampal pathways.

Thrombophilic factors in idiopathic intracranial hypertension: a report of 51 patients and a meta-analysis.

Several studies have suggested that thrombophilic risk factors are more prevalent in individuals with idiopathic intracranial hypertension (IIH), and that a prothrombic state may be involved in the etiopathogenesis of this disease. We examine thrombophilic factors in a group of patients with IIH in relation to obesity. In addition, we reviewed the relevant literature and performed a meta-analysis. Thrombophilia work-up was performed on 51 patients with IIH at least 1 month following their first episode. Samples for the analysis of factor V Leiden (FVL), prothrombin gene variant (PGV) G20210A and methylenetetrahydrofolate reductase (MTHFR) were available in an additional 30 patients, that is 81 patients in all. Meta-analysis was performed. Of the 51 patients 40 were obese. Increased concentrations of fibrinogen, D-Dimer, factor VIII, factor IX and factor XI were found in 15, 7, 7, 6 and 2 patients, respectively, all obese. The circulating anticoagulant, measured by dilute Russell's viper venom time (dRVVT assay), found mainly in obese. All 51 patients were negative for the anticardiolipin antibody (IgG immunoglobulin G) and IgG anti-beta2 glycoprotein I. In the meta-analysis antiphospholipid antibodies were significantly associated with IIH [odds ratio (OR) of 4.25 (1.68-12.60)], similar to the association with high factor VIII [OR = 16.17 (2.87-91.01)], higher plasminogen activator inhibitor-1 (PAI-1) levels [OR = 6.91 (2.28-20.91)], and high lipoprotein (a) [LP(a)] [OR = 3.54 (1.54-8.70)]. Obesity often observed in IIH patients is frequently linked with thrombophilic factors. Thus, we believe that dysmetabolism could be the thrombophilic target for treatment in patients with IIH.

Erythrocyte aggregation as an early biomarker in patients with asymptomatic carotid stenosis.

BACKGROUND: Atherosclerosis is a chronic inflammatory disease. DESIGN: We have evaluated the degree of erythrocyte aggregation (EA) as a microinflammatory biomarker in a cohort of hospital-based, neurologically asymptomatic outpatients. METHODS: The degree of EA and carotid artery stenosis was evaluated in 510 individuals by using a simple slide test and image analysis. RESULTS: Four hundred and sixteen individuals had minimal carotid stenosis (< 30%); 47 had mild to moderate stenosis (30-69%) and 47 had severe stenosis (> 70%). A significant correlation was noted between the degree of carotid stenosis and the erythrocyte sedimentation rate (ESR), white blood cell count (WBCC) and fibrinogen (r=0.160, p=0.005; r=0.191, p=0.001 and r=0.126, p=0.026, respectively). The significant correlation was noted between the degree of carotid stenosis and EA (r=0.209, p< 0.001). The subjects with severe stenosis differed significantly from the other groups in their ESR, WBCC and EA. High sensitivity C-reactive protein (hs-CRP) concentrations did not discriminate between the presence and absence of significant carotid atherosclerotic disease. CONCLUSIONS: Inflammatory biomarkers such as ESR and the EA test are more sensitive than hs-CRP to the presence of a significant atherosclerotic carotid burden. These biomarkers might aid in the detection and quantification of microinflammation in individuals with carotid atherosclerosis.

Early signaling of inflammation in acute ischemic stroke: clinical and rheological implications.

INTRODUCTION: Several studies have highlighted the role of interleukin-6 (IL-6) as an early signal of the inflammatory response following acute ischemic stroke. This study examines the potential advantage of employing high-sensitivity (hs)-IL-6 as a possible biomarker at the early stages of acute stroke for identifying an acute phase response and its potential rheological and clinical implications. METHODS: Venous blood was obtained from 186 stroke patients within 24 h of hospital admission and 3-5 days thereafter in order to characterize an inflammatory and hemorheological profile (including erythrocyte aggregation). Neurological state was assessed by the National Institutes of Health Stroke Scale (NIHSS) and the modified Rankin scale (mRs). RESULTS: While most biomarkers displayed elevated concentrations with time, serum concentrations of hs-IL-6 declined 3-5 days following acute stroke. Initially elevated levels of hs-IL-6 at presentation further correlated with unfavorable clinical outcomes (by NIHSS and mRs) at both time points. Analysis of variance in the different quartiles identified an hs-IL-6 gradient-dependent correlation at both time points, such that the higher the initial hs-IL-6 concentration, the higher the elevation in inflammatory biomarkers and the poorer the neurological state at both time points (p<0.001 for NIHSS and p=0.001 for mRs, for trend across quartiles). CONCLUSIONS: This study demonstrates the potential of employing hs-IL-6 as an early stage biomarker for the prognosis of acute ischemic stroke. Such an advance would provide the means to identify at an early stage the patients who would require closer clinical surveillance and/or administration of therapeutic interventions.

Increased red blood cell aggregation in patients with idiopathic intracranial hypertension. A hitherto unexplored pathophysiological pathway.

It was the objective of this study to explore the possibility that the aggregation of red blood cells is enhanced in individuals with increased intracranial hypertension (IIH). This is a prospective cross sectional examination in a cohort of patients with IIH and matched controls. The aggregation of red blood cells in the peripheral venous blood was determined by using a slide test and image analysis. We have presently included a group of 33 women with IIH and the same number of women matched for age, body mass index, vascular risk factors and medications. A significant (p = 0.038) increment in fibrinogen concentrations was noted in the patients (341 +/- 60.8 mg/dl) as opposed to the controls 307.9 +/- 64.8). The same stands for the aggregation of red blood cells (aggregation parameter of 8.7 +/- 4.9 in patients vs.5.9 +/- 3.2 in the controls, p = 0.001). We noted an increment in the aggregation of red blood cells in the peripheral blood of 33 women with IIH as opposed to matched controls. Being associated with capillary slow flow, these findings might be relevant to the ethiopathogenesis of this disease.

Inflammation-sensitive proteins and erythrocyte aggregation in atherothrombosis.

OBJECTIVE: To find the relative contribution of various inflammation-sensitive proteins including fibrinogen, immunoglobulins (IgG, IgM and IgA), ceruloplasmin and high sensitivity C-reactive protein (hs-CRP) to the induction and/or maintenance of enhanced erythrocyte adhesiveness/aggregation in the peripheral blood of individuals with atherothrombotic risk factors. METHODS: The degree of erythrocyte adhesiveness/aggregation was determined by a simple slide test and image analysis. In addition, we measured various inflammation-sensitive protein levels including fibrinogen, ceruloplasmin, immunoglobulins and hs-CRP in a group of 234 individuals with atherothrombotic risk factors and healthy ones. Pearson partial correlations and multiple linear regression analysis were performed. RESULTS: Fibrinogen was found to be the major protein contributing to the enhanced erythrocyte adhesiveness/aggregation, explaining 30% of the model. Fibrinogen and IgG together explained 32.4% of the model. Other inflammation-sensitive proteins did not reach statistical significance and were excluded from the model. CONCLUSIONS: Among inflammation-sensitive proteins measured in our cohort, fibrinogen is the dominant contributor to erythrocyte adhesiveness/aggregation in the peripheral blood of individuals with atherothrombotic risk factors and healthy ones. These findings may pave the way for the development of therapeutic strategies directed at the attenuation of erythrocyte aggregability in individuals with atherothrombosis.

A simple biomarker to exclude the presence of low grade inflammation in apparently healthy individuals.

BACKGROUND: Atherosclerosis is accompanied by a low grade inflammatory response. HYPOTHESIS: To use erythrocyte aggregability as a biomarker to exclude the presence of low grade inflammatory response in apparently healthy individuals. METHODS: The adhesiveness/aggregation of red blood cells was quantitated by using a simple slide test and image analysis. RESULTS: We included 121 apparently healthy individuals and found a significant correlation between the degree of erythrocyte adhesiveness/aggregation and either the concentration of high sensitive CRP (r = 0.6, P < 0.001), erythrocyte sedimentation rate (r = 0.5, P < 0.0001) or fibrinogen (r = 0.5, P < 0.0001). By using certain cutoff points for the erythrocyte adhesiveness/aggregation test we could define individuals with a very low grade inflammatory response. CONCLUSIONS: By using this inexpensive and rapid assessment, we could clearly discriminate between individuals with a very low inflammatory response and those with a more intense one. This biomarker should be further evaluated as a possible screening test for use in large populations of apparently healthy individuals in whom the detection of low grade inflammation might contribute to guiding appropriate lifestyle modifications and therapeutic interventions.