Dose-Dependent Association of Inflammatory Cytokines with Carotid Atherosclerosis in Transient Ischaemic Attack: Implications for Clinical Trials.

INTRODUCTION: The 5-year recurrence risk after ischaemic stroke and transient ischaemic attack (TIA) is 25-30%. Although inflammation may be a target for prevention trials, the contribution of plaque inflammation to acute cerebrovascular events remains unclear. We investigated the association of acute inflammatory cytokines and high-sensitivity C-reactive protein (CRP) with recently symptomatic carotid atherosclerosis in a prospective cohort study. METHODS: Blood and Imaging markers of TIA BIO-TIA) is a multicentre prospective study of imaging and inflammatory markers in patients with TIA. Exclusion criteria were infection and other co-morbid illnesses associated with inflammation. CRP and serum cytokines (interleukin [IL]-6, IL-1ß, IL-8, IL-10, IL-12, interferon-γ [IFN-γ] and tumour necrosis factor-α [TNF-α]) were measured. All patients had carotid imaging. RESULTS: Two hundred and thirty-eight TIA cases and 64 controls (TIA mimics) were included. Forty-nine (20.6%) cases had symptomatic internal carotid artery stenosis. Pro-inflammatory cytokine levels increased in a dose-dependent manner across controls, TIA without carotid stenosis (CS), and TIA with CS (IL-1ß, ptrend = 0.03; IL-6, ptrend < 0.0001; IL-8, ptrend = 0.01; interferon (IFN)-γ, ptrend = 0.005; TNF-α, ptrend = 0.003). Results were unchanged when DWI-positive cases were excluded. On multivariable linear regression, only age (p = 0.01) and CS (p = 0.04) independently predicted log-IL-6. On multivariable Cox regression, CRP was the only independent predictor of 90-day stroke recurrence (adjusted hazard ratio per 1-unit increase 1.03 [95% CI: 1.01-1.05], p = 0.003). CONCLUSION: Symptomatic carotid atherosclerosis was associated with elevated cytokines in TIA patients after controlling for other sources of inflammation. High-sensitivity CRP was associated with recurrent ischaemic stroke at 90 days. These findings implicate acute plaque inflammation in the pathogenesis of cerebral thromboembolism and support a rationale for randomized trials of anti-inflammatory therapy for stroke patients, who were excluded from coronary trials.

Carotid Plaque Inflammation Imaged by PET and Prediction of Recurrent Stroke at 5 Years.

BACKGROUND AND OBJECTIVES: To determine whether carotid plaque inflammation identified by 18F-fluorodeoxyglucose (18FDG)-PET is associated with late (5-year) recurrent stroke. METHODS: We did an individual-participant data pooled analysis of 3 prospective studies with near-identical study methods. Eligible patients had recent nonsevere (modified Rankin Scale score ≤3) ischemic stroke/TIA and ipsilateral carotid stenosis (50%-99%). Participants underwent carotid 18FDG-PET/CT angiography ≤14 days after recruitment. 18FDG uptake was expressed as maximum standardized uptake value (SUVmax) in the axial single hottest slice of symptomatic plaque. We calculated the previously validated Symptomatic Carotid Atheroma Inflammation Lumen-Stenosis (SCAIL) score, which incorporates a measure of stenosis severity and 18FDG uptake. The primary outcome was 5-year recurrent ipsilateral ischemic stroke after PET imaging. RESULTS: Of 183 eligible patients, 181 patients completed follow-up (98.9%). The median duration of follow-up was 4.9 years (interquartile range 3.3-6.4 years, cumulative follow-up period 901.8 patient-years). After PET imaging, 17 patients had a recurrent ipsilateral ischemic strokes at 5 years (recurrence rate 9.4%, 95% confidence interval [CI] 5.6%-14.6%). Baseline plaque SUVmax independently predicted 5-year ipsilateral recurrent stroke after adjustment for age, sex, carotid revascularization, stenosis severity, NIH Stroke Scale score, and diabetes mellitus (adjusted hazard ratio [HR] 1.98, 95% CI 1.10-3.56, p = 0.02 per 1-g/mL increase in SUVmax). On multivariable Cox regression, SCAIL score predicted 5-year ipsilateral stroke (adjusted HR 2.73 per 1-point increase, 95% CI 1.52-4.90, p = 0.001). DISCUSSION: Plaque inflammation-related 18FDG uptake improved identification of 5-year recurrent ipsilateral ischemic stroke. Addition of plaque inflammation to current selection strategies may target patients most likely to have late and early benefit from carotid revascularization. CLASSIFICATION OF EVIDENCE: This study provides Class I evidence that in individuals with recent ischemic stroke/TIA and ipsilateral carotid stenosis, carotid plaque inflammation-related 18FDG uptake on PET/CT angiography was associated with 5-year recurrent ipsilateral stroke.

Cohort profile: BIOVASC-late, a prospective multicentred study of imaging and blood biomarkers of carotid plaque inflammation and risk of late vascular recurrence after non-severe stroke in Ireland.

PURPOSE: Inflammation is important in stroke. Anti-inflammatory therapy reduces vascular events in coronary patients. 18F-fluorodeoxyglucose positron emission tomography (18F-FDG-PET) identifies plaque inflammation-related metabolism. However, long-term prospective cohort studies investigating the association between carotid plaque inflammation, identified on 18F-FDG PET and the risk of recurrent vascular events, have not yet been undertaken in patients with stroke. PARTICIPANTS: The Biomarkers Imaging Vulnerable Atherosclerosis in Symptomatic Carotid disease (BIOVASC) study and Dublin Carotid Atherosclerosis Study (DUCASS) are two prospective multicentred observational cohort studies, employing near-identical methodologies, which recruited 285 patients between 2008 and 2016 with non-severe stroke/transient ischaemic attack and ipsilateral carotid stenosis (50%-99%). Patients underwent coregistered carotid 18F-FDG PET/CT angiography and phlebotomy for measurement of inflammatory cytokines. Plaque 18F-FDG-uptake is expressed as maximum standardised uptake value (SUVmax) and tissue-to-background ratio. The BIOVASC-Late study is a follow-up study (median 7 years) of patients recruited to the DUCASS/BIOVASC cohorts. FINDINGS TO DATE: We have reported that 18F-FDG-uptake in atherosclerotic plaques of patients with symptomatic carotid stenosis predicts early recurrent stroke, independent of luminal narrowing. The incorporation of 18F-FDG plaque uptake into a clinical prediction model also improves discrimination of early recurrent stroke, when compared with risk stratification by luminal stenosis alone. However, the relationship between 18F-FDG-uptake and late vascular events has not been investigated to date. FUTURE PLANS: The primary aim of BIOVASC-Late is to investigate the association between SUVmax in symptomatic 'culprit' carotid plaque (as a marker of systemic inflammatory atherosclerosis) and the composite outcome of any late major vascular event (recurrent ischaemic stroke, coronary event or vascular death). Secondary aims are to investigate associations between: (1) SUVmax in symptomatic plaque, and individual vascular endpoints (2) SUVmax in asymptomatic contralateral carotid plaque and SUVmax in ipsilateral symptomatic plaque (3) SUVmax in asymptomatic carotid plaque and major vascular events (4) inflammatory cytokines and vascular events.

Anti-inflammatory therapy for preventing stroke and other vascular events after ischaemic stroke or transient ischaemic attack.

BACKGROUND: An increasing body of evidence suggests that inflammation plays a key role in stroke, in particular stroke of atherosclerotic origin. Anti-inflammatory medications are a widely heterogeneous group of drugs that are used to suppress the innate inflammatory pathway and thus prevent persistent or recurrent inflammation. Anti-inflammatory agents have the potential to stabilise atherosclerotic plaques by impeding the inflammatory pathway. By targeting specific cytokines, the inflammatory pathway may be interrupted at various stages. OBJECTIVES: To assess the benefits and harms of anti-inflammatory medications plus standard care versus standard care with or without placebo for prevention of vascular events (stroke, myocardial infarction (MI), non-fatal cardiac arrest, unstable angina requiring revascularisation, vascular death) and all-cause mortality in people with a prior history of ischaemic stroke or transient ischaemic attack (TIA). SEARCH METHODS: We searched the Cochrane Central Register of Controlled Trials (CENTRAL; last searched 29 May 2019); MEDLINE (1948 to 29 May 2019); Embase (1980 to 29 May 2019); the Cumulative Index to Nursing and Allied Health Literature (CINAHL; 1982 to 29 May 2019); and Scopus (1995 to 29 May 2019). In an effort to identify additional published, unpublished, and ongoing trials, we searched several grey literature sources (last searched 30 May 2019). We incorporated all identified studies into the results section. We applied no restrictions with respect to language, date of publication, or study setting. SELECTION CRITERIA: We considered randomised controlled trials (RCTs) and cluster-randomised controlled trials that evaluated anti-inflammatory medications for prevention of major cardiovascular events following ischaemic stroke or TIA. DATA COLLECTION AND ANALYSIS: Two review authors independently assessed for inclusion titles and abstracts of studies identified by the search. Two review authors independently reviewed full-text articles for inclusion in this review. We planned to assess risk of bias and to apply the GRADE method. MAIN RESULTS: We identified no studies that met the inclusion criteria. AUTHORS' CONCLUSIONS: There is currently a paucity of evidence on the use of anti-inflammatory medications for prevention of major cardiovascular events following ischaemic stroke or TIA. RCTs are needed to assess whether use of anti-inflammatory medications in this setting is beneficial.

Anti-inflammatory approaches to ischaemic stroke prevention.

Stroke is a major cause of neurological morbidity and mortality. Atherosclerosis is a major contributor to first and recurrent stroke. A growing evidence base indicates that inflammation is a key process in the pathogenesis of atherosclerosis, leading to thromboembolic events. In this review, we summarise the evidence linking inflammation to stroke risk and discuss clinical trials addressing the 'inflammation hypothesis' in coronary disease and stroke. Trial registration number CONVINCE trial ClinicalTrials.gov number; NCT 02898610; Pre-results.

Are there opportunities for a closer collaboration on clinical stroke research in Europe?

INTRODUCTION: One of the aims of the European Stroke Organisation (ESO) is to facilitate academic, multinational clinical stroke research. However, despite examples of successful regional and national stroke research networks and collaborative groups, there is no organisational structure at a European level that can facilitate multinational clinical stroke research. MATERIALS AND METHODS: In a project including a survey and a workshop and involving stroke researchers in the ESO, we sought to identify the challenges faced by existing clinical stroke research networks, to define the purpose and roles of any future European stroke research collaboration, and to propose an organisational structure. RESULTS: The survey and workshop gave strong support for an alliance model with independent network members, with the purpose of facilitating clinical stroke research through improved coordination and communication, provision of support, education, and advocacy and communication with other stakeholders. The focus of a proposed European clinical stroke research alliance should be multinational randomised-controlled trials in acute care, prevention and rehabilitation, but the alliance could also support other forms of multi-national clinical stroke research. CONCLUSION: There is an interest for increased collaboration on multinational clinical stroke research in Europe, in the form of an alliance of independent research networks and collaborative groups. The ESO Trials Network Committee will continue consultation with existing stroke research networks and collaborative groups, and other key stakeholders, to assess the feasibility and support for development of an ESO Trials Alliance.

Validation of a consensus method for identifying delirium from hospital records.

BACKGROUND: Delirium is increasingly considered to be an important determinant of trajectories of cognitive decline. Therefore, analyses of existing cohort studies measuring cognitive outcomes could benefit from methods to ascertain a retrospective delirium diagnosis. This study aimed to develop and validate such a method for delirium detection using routine medical records in UK and Ireland. METHODS: A point prevalence study of delirium provided the reference-standard ratings for delirium diagnosis. Blinded to study results, clinical vignettes were compiled from participants' medical records in a standardised manner, describing any relevant delirium symptoms recorded in the whole case record for the period leading up to case-ascertainment. An expert panel rated each vignette as unlikely, possible, or probable delirium and disagreements were resolved by consensus. RESULTS: From 95 case records, 424 vignettes were abstracted by 5 trained clinicians. There were 29 delirium cases according to the reference standard. Median age of subjects was 76.6 years (interquartile range 54.6 to 82.5). Against the original study DSM-IV diagnosis, the chart abstraction method gave a positive likelihood ratio (LR) of 7.8 (95% CI 5.7-12.0) and the negative LR of 0.45 (95% CI 0.40-0.47) for probable delirium (sensitivity 0.58 (95% CI 0.53-0.62); specificity 0.93 (95% CI 0.90-0.95); AUC 0.86 (95% CI 0.82-0.89)). The method diagnosed possible delirium with positive LR 3.5 (95% CI 2.9-4.3) and negative LR 0.15 (95% CI 0.11-0.21) (sensitivity 0.89 (95% CI 0.85-0.91); specificity 0.75 (95% CI 0.71-0.79); AUC 0.86 (95% CI 0.80-0.89)). CONCLUSIONS: This chart abstraction method can retrospectively diagnose delirium in hospitalised patients with good accuracy. This has potential for retrospectively identifying delirium in cohort studies where routine medical records are available. This example of record linkage between hospitalisations and epidemiological data may lead to further insights into the inter-relationship between acute illness, as an exposure, for a range of chronic health outcomes.