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.

Does Chronic Kidney Disease Have an Impact on the Use of Oral Anticoagulants after Stroke? An Observational Follow-Up Study.

INTRODUCTION: Chronic kidney disease is common in patients with acute ischemic stroke. We investigated whether chronic kidney disease has an impact on anticoagulation treatment recommendations after ischemic stroke or transient ischemic attack (TIA) related with atrial fibrillation (AF). MATERIALS AND METHODS: We extracted treatment-related data concerning stroke/TIA patients with AF and available estimated glomerular filtration rates (eGFR) from a monocentric prospective German stroke registry. Chronic kidney disease was defined as eGFR <60 mL/min/1.73 m2. Using uni- and multivariate logistic regression analyses, we investigated whether chronic kidney disease was associated with a lower probability to be treated with anticoagulation early after stroke. RESULTS: A total of 273 patients entered the analysis. In 242 AF patients (88.6%), oral anticoagulation was recommended after stroke. In multivariate logistic regression analysis, chronic kidney disease was not identified as an independent factor for the decision against anticoagulation (OR 1.63, 95% CI: 0.50-5.31, p = 0.421); only increasing age (OR 1.10, 95% CI: 1.00-1.21, p = 0.061) and a modified Rankin Scale >3 at discharge (OR 3.41, 95% CI: 0.88-13.24, p = 0.077) showed a nonsignificant trend for the decision to omit anticoagulation. A total of 155 of 167 patients (92.8%) were still anticoagulated at follow-up. A total of 44 patients with chronic kidney disease completed follow-up, and of those, 37 were still anticoagulated (84%). In patients without chronic kidney disease, 118/167 (70.7%) had continued anticoagulation (p = 0.310). CONCLUSION: Our results show that chronic kidney disease was not the main factor in the decision to withhold oral anticoagulation in patients with recent stroke/TIA and AF.

[Aquaporin-4 and Myelin Oligodendrocyte Glycoprotein Antibody-Associated Optic Neuritis: Diagnosis and Treatment]. / Aquaporin-4- und Myelin-Oligodendrozyten-Glykoprotein-Antikörper-assoziierte Optikusneuritis: Diagnose und Therapie.

Optic neuritis (ON) is a frequent manifestation of aquaporin-4 (AQP4) antibody-mediated neuromyelitis optica spectrum disorders (NMOSD) and myelin oligodendrocyte glycoprotein antibody-associated encephalomyelitis (MOG-EM; also termed MOG antibody-associated disorders, MOGAD). The past few years have seen major advances in the diagnosis and treatment of these two relatively new entities: international diagnostic criteria for NMOSD and MOG-EM have been proposed, improved antibody assays developed, and consensus recommendations on the indications and methodology of serological testing published. Very recently, the results of four phase III trials assessing new treatment options for NMOSD have been presented. With eculizumab, a monoclonal antibody inhibiting complement factor C5, for the first time a relapse-preventing long-term treatment for NMOSD - which has so far mostly been treated off-label with rituximab, azathioprine, and other immunosuppressants - has been approved. Data from recent retrospective studies evaluating treatment responses in MOG-ON suggest that rituximab and other immunosuppressants are effective also in this entity. By contrast, many drugs approved for the treatment of multiple sclerosis (MS) have been found to be either ineffective or to cause disease exacerbation (e.g., interferon-ß). Recent studies have shown that not only NMOSD-ON but also MOG-ON usually follows a relapsing course. If left untreated, both disorders can result in severe visual deficiency or blindness, though MOG-ON seems to have a better prognosis overall. Acute attacks are treated with high-dose intravenous methylprednisolone and, in many cases, plasma exchange (PEX) or immunoadsorption (IA). Early use of PEX/IA may prevent persisting visual loss and improve the long-term outcome. Especially MOG-ON has been found to be frequently associated with flare-ups, if steroids are not tapered, and to underlie many cases of "chronic relapsing inflammatory optic neuropathy" (CRION). Both NMOSD-ON and MOG-ON are often associated with simultaneous or consecutive attacks of myelitis and brainstem encephalitis; in contrast to earlier assumptions, supratentorial MRI brain lesions are a common finding and do not preclude the diagnosis. In this article, we review the current knowledge on the clinical presentation, epidemiology, diagnosis, and treatment of these two rare yet important differential diagnoses of both MS-associated ON und idiopathic autoimmune ON.

Preexisting Heart Disease Underlies Newly Diagnosed Atrial Fibrillation After Acute Ischemic Stroke.

BACKGROUND AND PURPOSE: Whether newly diagnosed atrial fibrillation (nAF) after stroke reflects underlying heart disease and represents an increased risk of cardioembolic stroke, or whether it is triggered by neurogenic mechanisms remains uncertain. We investigated, whether cardiovascular risk factors and echocardiographic parameters in patients with nAF are similar to patients with known AF (kAF) and differ from patients without AF. METHODS: Consecutive acute ischemic stroke patients were enrolled into a prospective stroke database. All patients with echocardiography were included and univariable and multivariable testing was applied to compare clinical characteristics and echocardiographic findings among patients with nAF, kAF, and no AF. RESULTS: A total of 1397 patients were included (male, 62.3%; median age, 71 years). AF was present in 320 (22.9%) patients. Of those, nAF was present in 36.2% (116/320) and kAF in 63.8% (204/320). No clinical or echocardiographic factor was independently associated with detection of nAF compared with kAF but a trend toward larger left atrial diameters in patients with kAF was observed (P=0.070). In contrast, patients with nAF were more often female (P<0.001), older (P<0.001) and had a larger left atrial diameters (P<0.001) compared with patients without AF. While stroke severity in patients with nAF and kAF was similar, patients without AF had less severe strokes. CONCLUSIONS: Stroke patients with nAF and with kAF share common cardiovascular risk factors, have similar echocardiographic findings and suffer equally severe strokes. We conclude that preexisting heart disease is the major cause of AF that is first diagnosed after stroke.

Reversal strategies for vitamin K antagonists in acute intracerebral hemorrhage.

OBJECTIVE: There is little evidence to guide treatment strategies for intracerebral hemorrhage on vitamin K antagonists (VKA-ICH). Treatments utilized in clinical practice include fresh frozen plasma (FFP) and prothrombin complex concentrate (PCC). Our aim was to compare case fatality with different reversal strategies. METHODS: We pooled individual ICH patient data from 16 stroke registries in 9 countries (n = 10 282), of whom 1,797 (17%) were on VKA. After excluding 250 patients with international normalized ratio < 1.3 and/or missing data required for analysis, we compared all-cause 30-day case fatality using Cox regression. RESULTS: We included 1,547 patients treated with FFP (n = 377, 24%), PCC (n = 585, 38%), both (n = 131, 9%), or neither (n = 454, 29%). The crude case fatality and adjusted hazard ratio (HR) were highest with no reversal (61.7%, HR = 2.540, 95% confidence interval [CI] = 1.784-3.616, p < 0.001), followed by FFP alone (45.6%, HR = 1.344, 95% CI = 0.934-1.934, p = 0.112), then PCC alone (37.3%, HR = 1.445, 95% CI = 1.014-2.058, p = 0.041), compared to reversal with both FFP and PCC (27.8%, reference). Outcomes with PCC versus FFP were similar (HR = 1.075, 95% CI = 0.874-1.323, p = 0.492); 4-factor PCC (n = 441) was associated with higher case fatality compared to 3-factor PCC (n = 144, HR = 1.441, 95% CI = 1.041-1.995, p = 0.027). INTERPRETATION: The combination of FFP and PCC might be associated with the lowest case fatality in reversal of VKA-ICH, and FFP may be equivalent to PCC. Randomized controlled trials with functional outcomes are needed to establish the most effective treatment.

Cognitive impairment is not a predictor of failure to adhere to anticoagulation of stroke patients with atrial fibrillation.

BACKGROUND: Oral anticoagulation (OAC) with vitamin K antagonists (VKA) or direct oral anticoagulants (DOAC) is an effective strategy that is used for stroke prevention in patients with atrial fibrillation (AF). However, OAC is underused particularly in elderly patients, who are often physically disabled or cognitively impaired. We aimed at evaluating the effect of cognitive status and disability on OAC adherence 1 year after stroke or TIA. METHODS: In this prospective, single-center, observational study patients with ischemic stroke or TIA were consecutively included between 3/2011 and 9/2012. The detailed medical history, basic demographic variables, cardiovascular risk factors, stroke severity according to the National Institutes of Health Stroke Scale (NIHSS), medication including OAC were all recorded. Cognitive performance was measured using the Montreal Cognitive Assessment (MoCA) score at baseline. The functional status was assessed by recording activities and instrumental activities of daily living, respectively (ADL, IADL). After 12 months, patients had a follow-up visit to reassess the cognitive and functional status (MoCA, ADL and IADL) and to document the current use of OAC. RESULTS: In total, 12 months after the ischemic stroke or TIA AF had been diagnosed in 160/586 (27.3%). Of these, 151 patients (94.4%) were treated with OAC. OAC was performed using VKA in 79/151 (52.3%) and DOACs in 72/151 (47.7%). Cognitive impairment at 12 months follow-up was not associated with the absence of OAC treatment. However, regression analysis revealed that patients with AF with physical (ADL) and functional disability (IADL) were less likely to be treated with OAC (p = 0.08 and p = 0.04, respectively) 12 months after a stroke. None of these two factors, however, was independently associated with nonadherence to OAC 12 months after stroke. Although cognitive performance was similar in patients receiving VKA and direct anticoagulants (DOAC), adherence to VKA tended to be lower (82.6 vs. 94.6%, p = 0.12). CONCLUSIONS: In stroke and TIA patients with AF, the multifactorial medical and functional constellation rather than cognitive impairment specifically can be an obstacle for long-term OAC.

Reasons underlying non-adherence to and discontinuation of anticoagulation in secondary stroke prevention among patients with atrial fibrillation.

BACKGROUND: Although long-term oral anticoagulation (OAC) with vitamin K antagonists for secondary stroke prevention in atrial fibrillation (AF) is highly effective, it is frequently not started or discontinued in clinical practice. We analyzed the reasons for stroke patients' and physician's nonadherence. METHODS: In this prospective, observational, single-center cohort study, consecutive patients diagnosed with acute ischemic stroke or transient ischemic attack (TIA) and AF presenting during a nine-month period were included. Adherence to OAC was evaluated at 15 ± 1 months after the event using a semi-structured telephone interview. In patients without anticoagulation, the primary care physician (PCP) was contacted to explore the reason. Associations between nonadherence to OAC therapy at follow-up and potential predictors were assessed by logistic regression analysis. RESULTS: Of the 1,049 presenting stroke/TIA patients, 139 with a first (n = 101) or a continued recommendation (n = 38) of OAC were analyzed. After 15 months, 54 patients (39% of 85 patients with OAC at follow-up) were nonadherent. The main reasons for patients' nonadherence were fear of side effects (e.g., bleeding) and inconvenience of regular international normalized ratio measurements. In two-thirds (36/54) of cases, OAC was not prescribed by the PCP; the most important reasons were a putative high risk of falling and dementia. Risk factors for nonadherence were dementia, living in a nursing home, and the noninitiation of OAC during in-hospital stay. Treatment was temporarily discontinued in 21 (25%) of patients on OAC at follow-up. CONCLUSION: Nonadherence to OAC in stroke patients results from fear of potential complications or inconvenience and physicians' concerns regarding functional status. OAC should be initiated wherever possible during the in-hospital stay.

Intracerebral bleeding in patients on antithrombotic agents.

Patients treated with oral anticoagulants (OAC) carry a 7- to 10-fold higher risk of intracerebral hemorrhage (ICH) than patients without OAC. ICH related to oral anticoagulation (OAC-ICH) is a particularly severe form of stroke. The overall incidence of OAC-ICH ranges between 2 and 9 per 100,000 population/year and is expected to increase as the number of patients treated with OAC rises. Besides common risk factors of ICH such as age and hypertension, the intensity of anticoagulation, previous ischemic stroke, and the presence of cerebral vasculopathies (e.g., amyloid angiopathy, subcortical hypertensive arteriopathy) are associated with a greater risk of OAC-ICH. Mortality rates in OAC-ICH of 52 to 67% considerably exceed those of ICH in nonanticoagulated patients. Factors that mediate worse outcome in OAC-ICH are more frequent and prolonged secondary hematoma enlargement and intraventricular hemorrhage, The current concept of emergency treatment in OAC-ICH is rapid restoration of effective coagulation using hemostatic factors such as prothrombin complex concentrate, fresh frozen plasma, factor IX concentrates, and recombinant factor VIIa in addition to vitamin K. Emergency management of ICH under treatment with the new direct OAC is a major challenge. In the absence of specific antidotes, prothrombin concentrates are recommended mainly on the basis of preclinical data.

Spot signs in intracerebral hemorrhage: useful for identifying patients at risk for hematoma enlargement?

BACKGROUND: Prognostic signs for the identification of patients with acute spontaneous intracerebral hemorrhage (SICH) prone to hematoma expansion are limited. Contrast extravasation (spot signs, SpS) on computed tomographic angiography (CTA) may be a promising method to predict hematoma expansion in acute SICH. However, prospective data on the predictive value of the SpS on hematoma expansion and clinical outcome are still limited. We aimed to investigate associations between the presence of SpS, hematoma expansion, and clinical outcome in acute SICH. METHODS: A prospective observational study was performed between 08/2008 and 08/2011. Patients with SICH presenting within 6 h of symptom onset were included. Patients with secondary hematomas, purely intraventricular hematomas, incomplete CT evaluation, hematoma evacuation prior to follow-up brain imaging, and incomplete follow-up data and those who refused to give consent for data analysis were excluded. CT and CTA brain imaging were carried out in all patients at baseline. After 24 h, follow-up brain imaging was performed. Hematoma location, hematoma volume, and substantial hematoma expansion were documented. CTA images were evaluated by two investigators for the presence of SpS. In all positive SpS cases, images were additionally reviewed by a third rater to achieve consensus for interpretating contrast extravasation. Clinical outcome was measured by the modified Rankin Scale (mRS) at discharge and at 3 months. RESULTS: In total, 101 patients [median age 73 years (interquartile range 60-79); male 61.4%] were included in the analysis. Median time from onset to CTA was 128 min (interquartile range 90-209 min); median initial National Institute of Health Stroke Scale score was 16 (8-21). SpS were detected in 27 patients (26.7%). Cohen's kappa for the presence of SpS was 0.606, indicating moderate agreement. SpS patients had significantly higher initial hematoma volumes than patients without SpS (36.0 vs. 14.39 ml, p = 0.005). Hematoma expansion was significantly more frequent in SpS patients (59.3 vs. 21.6%, p < 0.001) and associated with the presence of SpS in the univariate analysis (OR 5.273; 95% CI 2.047-13.584, p = 0.001) and in multivariable analysis adjusted for the initial hematoma volume (OR 4.678, 95% CI 1.781-12.288, p = 0.002). Sensitivity of SpS to predict hematoma expansion was 0.5, specificity was 0.84. The positive likelihood ratio for SpS to predict hematoma expansion was 3.136 (95% CI 1.649-5.967), the negative likelihood ratio was 0.595 (95% CI 0.414-0.854). No difference in 3-month clinical outcome was observed between patients with and without SpS (median mRS score 4 and 4, p = 0.457). CONCLUSIONS: The clinical value of SpS needs to be further explored. Future studies should particularly focus on structured training procedures to identify SpS and measure the time needed to precisely assess the presence of SpS and on the prevalence of SpS in consecutive intracerebral hemorrhage populations.

Oral anticoagulants--a frequent challenge for the emergency management of acute ischemic stroke.

BACKGROUND: The emergency management of patients with acute ischemic stroke (IS) using oral anticoagulants (OAC) represents a great challenge. Effective anticoagulation predisposes to bleeding and represents a contraindication for systemic thrombolysis. However, patients on OAC can receive intravenous thrombolysis with recombinant tissue-type plasminogen activator if the international normalized ratio (INR) does not exceed 1.7, but data regarding the risk of hemorrhagic complications are highly controversial. Neurointerventional recanalization of intracranial artery occlusion represents an alternative option in OAC patients with acute IS. The proportion of OAC users among consecutive patients who suffer from acute IS or transient ichemic attacks (TIA) is unknown. METHODS: A prospective observational study, consecutively enrolling all patients with IS or TIA admitted to our neurological emergency room (ER), was performed between August 2009 and February 2011. Basic demographic variables, present use of OAC, severity of stroke, cardiovascular risk factors, INR values and the symptom onset to presentation time were recorded. In IS patients on OAC presenting within 4.5 h after symptom onset, management was analyzed. In thrombolysed IS patients, bleeding events were documented. Outcome was assessed after 3 months. RESULTS: During the study period, 12,237 patients were admitted to our neurological ER. IS or TIA were diagnosed in 2,074 (16.9%). Complete data were available for 1,914 of these subjects (92.3%); 53.8% were male (median age: 72 years). 69.7% suffered IS, 30.3% TIA. OAC were being used by 8.7% of all patients. OAC patients were older than non-OAC patients (78 vs. 72 years, p < 0.001). Subtherapeutic INR values (<2.0) were found in 67.3% of OAC patients with IS. 54.8% of all OAC IS patients presented at the ER within ≤4.5 h after the event (57/104). An INR ≤1.7 - compatible with systemic thrombolysis - was present in 33/57 patients (57.9%). Recanalization therapy was performed in 21/57 patients (36.8%). No difference in symptomatic or fatal intracerebral bleedings between thrombolysed patients with and without prior OAC use was observed (p = 0.720 and 0.135, respectively). Multivariable analysis of predictors of the 3-month outcome in IS patients revealed that prior medication with OAC was neither associated with an unfavorable clinical outcome after 3 months in the whole population of stroke patients (p = 0.235) nor in patients in whom recanalization approaches were used (n = 306; p = 0.271). CONCLUSIONS: Oral anticoagulation represents a frequent challenge for the emergency manangement of IS. A considerable proportion of anticoagulated IS patients appears to be eligible for thrombolysis. Establishing standardized treatment procedures in these patients is warranted.

Development of imaging-based risk scores for prediction of intracranial haemorrhage and ischaemic stroke in patients taking antithrombotic therapy after ischaemic stroke or transient ischaemic attack: a pooled analysis of individual patient data from cohort studies.

BACKGROUND: Balancing the risks of recurrent ischaemic stroke and intracranial haemorrhage is important for patients treated with antithrombotic therapy after ischaemic stroke or transient ischaemic attack. However, existing predictive models offer insufficient performance, particularly for assessing the risk of intracranial haemorrhage. We aimed to develop new risk scores incorporating clinical variables and cerebral microbleeds, an MRI biomarker of intracranial haemorrhage and ischaemic stroke risk. METHODS: We did a pooled analysis of individual-patient data from the Microbleeds International Collaborative Network (MICON), which includes 38 hospital-based prospective cohort studies from 18 countries. All studies recruited participants with previous ischaemic stroke or transient ischaemic attack, acquired baseline MRI allowing quantification of cerebral microbleeds, and followed-up participants for ischaemic stroke and intracranial haemorrhage. Participants not taking antithrombotic drugs were excluded. We developed Cox regression models to predict the 5-year risks of intracranial haemorrhage and ischaemic stroke, selecting candidate predictors on biological relevance and simplifying models using backward elimination. We derived integer risk scores for clinical use. We assessed model performance in internal validation, adjusted for optimism using bootstrapping. The study is registered on PROSPERO, CRD42016036602. FINDINGS: The included studies recruited participants between Aug 28, 2001, and Feb 4, 2018. 15 766 participants had follow-up for intracranial haemorrhage, and 15 784 for ischaemic stroke. Over a median follow-up of 2 years, 184 intracranial haemorrhages and 1048 ischaemic strokes were reported. The risk models we developed included cerebral microbleed burden and simple clinical variables. Optimism-adjusted c indices were 0·73 (95% CI 0·69-0·77) with a calibration slope of 0·94 (0·81-1·06) for the intracranial haemorrhage model and 0·63 (0·62-0·65) with a calibration slope of 0·97 (0·87-1·07) for the ischaemic stroke model. There was good agreement between predicted and observed risk for both models. INTERPRETATION: The MICON risk scores, incorporating clinical variables and cerebral microbleeds, offer predictive value for the long-term risks of intracranial haemorrhage and ischaemic stroke in patients prescribed antithrombotic therapy for secondary stroke prevention; external validation is warranted. FUNDING: British Heart Foundation and Stroke Association.

Matrix metalloproteinases in peripheral blood and cerebrospinal fluid in patients with Alzheimer's disease.

BACKGROUND: Deposition of amyloid beta in senile plaques and in cerebral blood vessels is one hallmark of the pathogenesis of Alzheimer's disease (AD). The ability of several matrix metalloproteinases (MMPs) to degrade amyloid precursor protein leading to aggregation of amyloid beta, as well as the increased expression of MMPs in post mortem brain tissue of Alzheimer's patients, indicate that MMPs play an important role in the pathogenesis of AD. METHODS: We investigated levels of MMP-2,-3,-9 and -10 in plasma and cerebrospinal fluid (CSF) of AD patients (n = 14) by gelatin and casein zymography. Comparisons between AD patients and controls relative to levels of MMP-2, MMP-3, MMP-9, and MMP-10 were made with Wilcoxon rank statistics. Pearson correlations were computed as measures of association. RESULTS: MMP-3 in AD was significantly elevated in plasma (p = 0.006) and there was a trend towards increase in CSF (p = 0.05). MMP-2 in CSF of AD patients was significantly decreased (p = 0.02) while levels in plasma remained unchanged. MMP-9 and MMP-10 could not be detected in CSF; MMP-10 was unchanged in plasma, but MMP-9 was significantly decreased (p = 0.02). CONCLUSIONS: These findings constitute further evidence for the important role of MMPs in the pathogenesis of AD.

Remission of paraneoplastic dermatomyositis associated with hepatocellular carcinoma under prednisolone and azathiopin, and concommittant sorafenib.

BACKGROUND: Hepatocellular carcinoma (HCC) is one of the most common tumor diseases worldwide. Dermatomyositis is a known paraneoplastic syndrome that can complicate the course of a variety of different cancers, however, the association with HCC is extremely rare. CASE REPORT: Here, we report on a patient with the rare concurrence of dermatomyositis and non-hepatitis-associated advanced HCC with intra-abdominal and intrathoracal lymph node metastases. The HCC was treated with sorafenib. The dermatomyositis responded well to treatment with prednisolone and azathioprin although sorafenib did not lead to a response in the underlying HCC. CONCLUSIONS: Paraneoplastic dermatomyositis can be associated with non-hepatitis-associated HCC. The potential pathogenetic links between these two diseases are discussed, as well as a potential immunomodulatory effect of sorafenib independent of its antineoplastic potential.

Increased expression of cell-cell signaling genes by stimulated mononuclear leukocytes in patients with previous atherothrombotic stroke. A whole genome expression profile study.

BACKGROUND/AIMS: Inflammation plays an important role in atherosclerosis and stroke. Acute infections are recognized as trigger factors for ischemic stroke. METHODS: In this whole genome expression profile study of 15 patients and 15 control subjects, we tested the hypothesis that patients with a history of atherothrombotic stroke show enhanced transcription of inflammatory genes in circulating leukocytes. RNA from unstimulated or lipopolysaccharide (LPS)-stimulated peripheral blood mononuclear cells (PBMCs) was analyzed with Affymetrix U133A GeneChips using a pooling design. Expression of single genes and functional groups of genes was analyzed by global statistical tests. RESULTS: A total of 10,197 probe sets showed positive calls. After correction for multiple testing no single probe set revealed significant differences either without or with LPS stimulation. However, significant global expression differences were found upon LPS stimulation for the group of genes that are involved in cell-cell signaling. CONCLUSION: LPS stimulation of PBMCs, a condition mimicking bacterial infection, induces differential expression of a group of cell-cell signaling genes in patients with previous atherothrombotic stroke. This finding can be caused by genetic differences between both groups, but acquired risk factors, medication and technical factors may also have contributed to the result.

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.

Minocycline and hypothermia for reperfusion injury after focal cerebral ischemia in the rat: effects on BBB breakdown and MMP expression in the acute and subacute phase.

Reperfusion injury is a complication of recanalization therapies after focal cerebral ischemia. The disruption of the blood-brain barrier (BBB) caused by up-regulated metalloproteinases (MMPs) can lead to edema and hemorrhage. Middle cerebral artery occlusion (MCAO=90 min) and reperfusion (R=24 h vs. 5 days) was induced in male Wistar rats. Rats were randomized in four groups: (1) control (C), (2) twice daily minocycline (30 mg/kg bodyweight) every day (M), (3) hypothermia (33 degrees C) for 4 h starting 60 min after occlusion (H), (4) combination of groups 2 and 3 (MH). Serial MRI was performed regarding infarct evolution and BBB disruption, MMP-2 and MMP-9 were assessed by zymography of serum and ischemic brain tissue, and a functional neuroscore was done at 24 h and 5 days. M and H reduced both infarct sizes, volume and signal intensity of BBB breakdown and improved neuroscore at all points in time to the same extent. This was most likely due to inhibition of MMP-2 and MMP-9. The presence of MMP-9 at 24 h or MMP-2 at 5 days in brain tissue correlated with BBB breakdown whereas serum MMP-2- and -9 showed no relationship with BBB breakdown. The combination MH had a small but not significantly additional effect over the single treatments. Minocycline seems to be as neuroprotective as hypothermia in the acute and subacute phase after cerebral ischemia. One essential mechanism is the inhibition of MMPs. The combination therapy is only slightly superior. The net effect of MMPs inhibition up to 5 days after focal cerebral ischemia is still beneficial.

Clinical significance of cerebral microbleeds on MRI: A comprehensive meta-analysis of risk of intracerebral hemorrhage, ischemic stroke, mortality, and dementia in cohort studies (v1).

Background Cerebral microbleeds can confer a high risk of intracerebral hemorrhage, ischemic stroke, death and dementia, but estimated risks remain imprecise and often conflicting. We investigated the association between cerebral microbleeds presence and these outcomes in a large meta-analysis of all published cohorts including: ischemic stroke/TIA, memory clinic, "high risk" elderly populations, and healthy individuals in population-based studies. Methods Cohorts (with > 100 participants) that assessed cerebral microbleeds presence on MRI, with subsequent follow-up (≥3 months) were identified. The association between cerebral microbleeds and each of the outcomes (ischemic stroke, intracerebral hemorrhage, death, and dementia) was quantified using random effects models of (a) unadjusted crude odds ratios and (b) covariate-adjusted hazard rations. Results We identified 31 cohorts ( n = 20,368): 19 ischemic stroke/TIA ( n = 7672), 4 memory clinic ( n = 1957), 3 high risk elderly ( n = 1458) and 5 population-based cohorts ( n = 11,722). Cerebral microbleeds were associated with an increased risk of ischemic stroke (OR: 2.14; 95% CI: 1.58-2.89 and adj-HR: 2.09; 95% CI: 1.71-2.57), but the relative increase in future intracerebral hemorrhage risk was greater (OR: 4.65; 95% CI: 2.68-8.08 and adj-HR: 3.93; 95% CI: 2.71-5.69). Cerebral microbleeds were an independent predictor of all-cause mortality (adj-HR: 1.36; 95% CI: 1.24-1.48). In three population-based studies, cerebral microbleeds were independently associated with incident dementia (adj-HR: 1.35; 95% CI: 1.00-1.82). Results were overall consistent in analyses stratified by different populations, but with different degrees of heterogeneity. Conclusions Our meta-analysis shows that cerebral microbleeds predict an increased risk of stroke, death, and dementia and provides up-to-date effect sizes across different clinical settings. These pooled estimates can inform clinical decisions and trials, further supporting cerebral microbleeds role as biomarkers of underlying subclinical brain pathology in research and clinical settings.

Diphenyleneiodonium and dimethylsulfoxide for treatment of reperfusion injury in cerebral ischemia of the rat.

Diphenyleneiodonium (DPI) is an inhibitor of the free radical producing NAD(P)H-oxidase. We tested whether DPI shows neuroprotective properties after focal cerebral ischemia and we used dimethylsulfoxide (DMSO), a nonspecific free radical scavenger, as a solvent. In male Wistar rats middle cerebral artery occlusion (1.5 h) and subsequent reperfusion (48 h) (MCAO/R) was induced with the filament model. Immediately after reperfusion the animals received either 0.25 ml normal saline, DMSO, or a combination of DMSO and DPI; each group consisted of 10 animals. MRI was performed at different times after reperfusion. Gelatine zymography of brain tissue for MMP-2 and MMP-9 was performed. The infarct sizes and BBB damage showed a significant difference between controls and the DPI/DMSO group for almost all points in time in all sequences. The activity of MMP-2 and MMP-9 was significantly reduced by DPI/DMSO but not by DMSO alone. DMSO treatment alone resulted in a protective effect with reduced lesion sizes measured by MRI at selected points of time, consistent with its known free radical scavenger effect. The combination of DMSO with DPI partly augmented this effect, presumably due to the additional inhibition of MMP-2 and MMP-9 by DPI. Moreover, the neurological outcome in both therapeutic groups was improved compared to controls with a significant difference between the therapeutic groups in favour of DPI and DMSO. The combination of DPI and DMSO reduced the activity of MMP-2 and MMP-9, attenuated the postischemic blood-brain barrier damage and improved neurological outcome. This was most likely due to reduced oxidative stress.

Brain microbleeds, anticoagulation, and hemorrhage risk: Meta-analysis in stroke patients with AF.

OBJECTIVES: To assess the association between cerebral microbleeds (CMBs) and future spontaneous intracerebral hemorrhage (ICH) risk in ischemic stroke patients with nonvalvular atrial fibrillation (AF) taking oral anticoagulants. METHODS: This was a meta-analysis of cohort studies with >50 patients with recent ischemic stroke and documented AF, brain MRI at baseline, long-term oral anticoagulation treatment, and ≥6 months of follow-up. Authors provided summary-level data on stroke outcomes stratified by CMB status. We estimated pooled annualized ICH and ischemic stroke rates from Poisson regression. We calculated odds ratios (ORs) of ICH by CMB presence/absence, ≥5 CMBs, and CMB topography (strictly lobar, mixed, and strictly deep) using random-effects models. RESULTS: We established an international collaboration and pooled data from 8 centers including 1,552 patients. The crude CMB prevalence was 30% and 7% for ≥5 CMBs. Baseline CMB presence (vs no CMB) was associated with ICH during follow-up (OR 2.68, 95% confidence interval [CI] 1.19-6.01, p = 0.017). Presence of ≥5 CMB was related to higher future ICH risk (OR 5.50, 95% CI 2.07-14.66, p = 0.001). The pooled annual ICH incidence increased from 0.30% (95% CI 0.04-0.55) among CMB-negative patients to 0.81% (95% CI 0.17-1.45) in CMB-positive patients (p = 0.01) and 2.48% (95% CI 1.2-6.2) in patients with ≥5 CMBs (p = 0.001). There was no association between CMBs and recurrent ischemic stroke. CONCLUSIONS: The presence of CMB on MRI and the dichotomized cutoff of ≥5 CMBs might identify subgroups of ischemic stroke patients with AF with high ICH risk and after further validation could help in risk stratification, in anticoagulation decisions, and in guiding randomized trials and ongoing large observational studies.

MMP-2 and MMP-9 levels in peripheral blood after subarachnoid hemorrhage.

MMPs play an important role in ischemic and hemorrhagic stroke. We analyzed replicate serum samples from 20 normal healthy individuals to assess reproducibility of MMP determinations, and found that MMP-2 and MMP-9 determinations were quite consistent. We then studied the serum levels of MMP-2 and MMP-9 in patients suffering from subarachnoid hemorrhage (SAH), another stroke subtype. Serum MMP-2 and MMP-9 levels from SAH patients were measured sequentially using gelatine zymography in 11 patients after acute SAH. The occurrence of intracerebral aneurysms and vasospasms and the initial Hunt and Hess score were analysed in relation to MMP-levels. MMP-2 levels are significantly decreased while MMP-9 levels are increased in SAH patients relative to controls. MMP-2 levels remain depressed out to day 12 post SAH, but MMP-9 levels may recover by day 12.