Asymmetric and symmetric dimethylarginine as markers of endothelial dysfunction in cerebrovascular disease: A prospective study.

BACKGROUND AND AIM: Asymmetric dimethylarginine (ADMA) and symmetric dimethylarginine (SDMA) have been proposed as mediators of endothelial dysfunction. In this study, we aimed to investigate the diagnostic and prognostic role of ADMA and SDMA in acute cerebrovascular disease. METHODS AND RESULTS: A prospective case-control study was performed, enrolling 48 patients affected by ischemic stroke with no cardioembolic origin, 20 patients affected by TIA, 40 subjects at high cardiovascular risk and 68 healthy subjects. ADMA levels were significantly lower in high-risk subjects (18.85 [11.78-22.83] µmol/L) than in patients with brain ischemic event, both transient (25.70 [13.15-40.20] µmol/L; p = 0.032) and permanent (24.50 [18.0-41.33] µmol/L; p = 0.001). SDMA levels were different not only between high-risk subjects and ischemic patients, but also between TIA and stroke patients, reaching higher levels in TIA group and lower levels in stroke group (1.15 [0.90-2.0] vs 0.68 [0.30-1.07] µmol/L; p < 0.001). SDMA was also correlated with short-term prognosis, with lower levels in case of adverse clinical course, evaluated by type of discharge (p = 0.009) and need of prolonged rehabilitation (p = 0.042). CONCLUSIONS: The present study highlights the relationship between l-arginine, ADMA, SDMA and acute cerebrovascular events. Therefore, our results suggested a potential role of SDMA as a specific marker of transient ischemic damage and as a short-term positive prognostic marker.

Serum sortilin as a predictor of stroke in patients with intermediate carotid artery stenosis.

BACKGROUND: Sortilin was an important molecular protein involved in the pathogenesis of atherosclerosis. Besides, serum sortilin was associated with adverse cerebrovascular events. Atherosclerotic stenosis in the carotid artery is a major etiology for ischemic stroke. The risk of stroke in patients with intermediate carotid artery stenosis (CAS) was unknown. Hence, the aim of the present study was to evaluate the relationship between serum sortilin levels and stroke in patients with intermediate CAS. METHODS: A total of 195 intermediate CAS patients were included in this cross-sectional study. The patients were divided into two groups as symptomatic (N = 95) and asymptomatic (N = 100) patients. Patients with a transient ischemic attack (TIA), retinal ischemic event, or ischemic stroke resulting from the narrowed carotid artery were considered to be symptomatic. Serum sortilin concentrations were measured using the enzyme-linked immunosorbent assay. RESULTS: Serum sortilin level was significantly higher in the symptomatic group than in the severe asymptomatic group (1.53 ± 0.25 ng/mL vs 1.34 ± 0.19 ng/mL, p < 0.001). Besides, high serum sortilin levels (odds ratio = 4.91, 95% confidence intervals 1.24-19.51, p = 0.023) were identified as independent predictors of symptomatic carotid plaque. In the receiver operating characteristic curve analysis, serum sortilin levels higher than 1.34 ng/mL predicted stroke/TIA with a sensitivity of 66.3% and a specificity of 67% (AUC = 0.725, p < 0.001). CONCLUSIONS: Serum sortilin level is increased in the presence of symptomatic intermediate CAS and may have clinical value in the management of patients with carotid artery disease.

Atherogenic Dyslipidemia and Residual Vascular Risk After Stroke or Transient Ischemic Attack.

BACKGROUND AND PURPOSE: Notwithstanding the current guideline-based management, patients with stroke retain a substantial risk of further vascular events. We aimed to assess the contribution of atherogenic dyslipidemia (AD) to this residual risk. METHODS: This was a prospective observational study, in which 792 patients (mean age, 70.1 years; male, 60.2%) with acute ischemic stroke (n=710) or transient ischemic attack (n=82) within 1 week of onset were consecutively enrolled and followed for 1 year. AD was defined as having both elevated levels of triglycerides ≥150 mg/dL and low HDL-C (high-density lipoprotein cholesterol) <40 mg/dL in men or <50 mg/dL in women, under fasting conditions. The primary outcome was a composite of major adverse cardiovascular events, including nonfatal stroke, nonfatal acute coronary syndrome, and vascular death. RESULTS: The prevalence of AD was 12.2%. Patients with AD more often had intracranial artery stenosis than those without (42.3% versus 24.1%; P=0.004), whereas no differences were observed in the prevalence of extracranial artery stenosis (17.7% versus 12.9%; P=0.62) or aortic plaques (33.3% versus 27.0%; P=0.87). At 1 year, patients with AD were at a greater risk of major adverse cardiovascular events (annual rate, 24.5% versus 10.6%; hazard ratio [95% CI], 2.33 [1.44-3.80]) and ischemic stroke (annual rate, 16.8% versus 8.6%; hazard ratio [95% CI], 1.84 [1.04-3.26]) than those without AD. When patients were stratified according to baseline LDL-C (low-density lipoprotein cholesterol) level, AD was predictive of major adverse cardiovascular events among those with LDL-C ≥100 mg/dL (n=509; annual rate, 20.5% versus 9.6%; P=0.036) as well as those with LDL-C <100 mg/dL (n=283; annual rate, 38.6% versus 12.4%; P<0.001). CONCLUSIONS: AD is associated with intracranial artery atherosclerosis and a high residual vascular risk after a stroke or transient ischemic attack. AD should be a promising modifiable target for secondary stroke prevention. Registration: URL: https://upload.umin.ac.jp; Unique identifier: UMIN000031913.

Cardiac Troponin and Recurrent Major Vascular Events after Minor Stroke or Transient Ischemic Attack.

OBJECTIVE: This study was undertaken to investigate whether high-sensitivity cardiac troponin T (hs-cTnT) is associated with major adverse cardiovascular events (MACE) in patients with minor stroke or transient ischemic attack (TIA), and whether this association differs after risk stratification based on the Age, Blood Pressure, Clinical Features, Duration of Symptoms, Diabetes (ABCD2 ) score. METHODS: INSPiRE-TMS was a randomized controlled trial allocating patients with minor stroke or TIA to an intensified support program or conventional care. In this post hoc analysis, participants were categorized using hs-cTnT levels (5th generation; Roche Diagnostics, Manheim, Germany; 99th percentile upper reference limit [URL] = 14ng/l). Vascular risk was stratified using the ABCD2 score (lower risk = 0-5 vs higher risk = 6-7). Cox proportional hazard regression was performed using covariate adjustment and propensity score matching (PSM) for the association between hs-cTnT and MACE (stroke/nonfatal coronary event/vascular death). RESULTS: Among 889 patients (mean age = 70 years, 37% female), MACE occurred in 153 patients (17.2%) during a mean follow-up of 3.2 years. hs-cTnT was associated with MACE (9.3%/yr, >URL vs 4.4%/yr, ≤URL, adjusted hazard ratio [HR] = 1.63 [95% confidence interval (CI) = 1.13-2.35], adjusted HR [Q4 vs Q1 ] = 2.57 [95% CI = 1.35-4.97], adjusted HR [log-transformed] = 2.31 [95% CI = 1.37-3.89]). This association remained after PSM (adjusted HR = 1.76 [95% CI = 1.14-2.72]). There was a significant interaction between hs-cTnT and ABCD2 category for MACE occurrence (pinteraction  = 0.04). In the lower risk category, MACE rate was 9.5%/yr in patients with hs-cTnT > URL, which was higher than in those ≤URL (3.8%/yr) and similar to the overall rate in the higher risk category. INTERPRETATION: hs-cTnT levels are associated with incident MACE within 3 years after minor stroke or TIA and may help to identify high-risk individuals otherwise deemed at lower risk based on the ABCD2 score. If confirmed in independent validation studies, this might warrant intensified secondary prevention measures and cardiac diagnostics in stroke patients with elevated hs-cTnT. ANN NEUROL 2021;90:901-912.

Association between haemoglobin A1c and cerebral microbleeds in community-based stroke-free individuals: A cross-sectional study.

AIMS: The association between haemoglobin A1c (HbA1c) and cerebral microbleeds (CMBs) remains unclear. We aimed to investigate the association between HbA1c and CMBs in community-based individuals without stroke or transient ischaemic attack (TIA) and whether the association differs between individuals with and without diabetes mellitus (DM). MATERIALS AND METHODS: All individuals were recruited from a community in Beijing, China, from January 2015 to September 2019. All individuals completed a questionnaire and underwent blood tests and brain magnetic resonance imaging. A susceptibility-weighted imaging sequence was acquired to detect CMBs, which were defined as small, round and low-signal lesions with <10 mm diameter. The association between HbA1c and CMBs was analysed using multivariable logistic regression adjusted for demographics, medical history and blood sample test results. Subgroup analyses stratified by history of DM were performed. RESULTS: Of 544 recruited individuals, 119 (21.88%) had CMBs. HbA1c was independently associated with CMBs (odds ratio [OR], 1.51; 95% confidence interval [CI], 1.03-2.22). In 87 individuals with DM, multivariable logistic analysis showed that HbA1c was significantly associated with CMBs (OR, 1.67; 95% CI, 1.04-2.69), whereas in individuals without DM, no significant association was observed between HbA1c and CMBs (OR, 1.07; 95% CI, 0.50-2.30). CONCLUSIONS: HbA1c was associated with CMBs in individuals without stroke or TIA, particularly in individuals with DM, suggesting that the status of glycaemic control warrants attention for the prevention of CMBs. It would be beneficial to manage HbA1c specifically to control the risk of CMBs, especially in individuals with DM.

Profile of reticulated platelets in the early, subacute and late phases after transient ischemic attack or ischemic stroke.

Information regarding the profile of reticulated platelets (RP) in ischemic cerebrovascular disease (CVD) patients is limited. Data from two prospective, observational, case-control studies were combined to compare the %RP using whole blood flow cytometry in patients ≤ 4 weeks of TIA/stroke onset (baseline, N = 210), and 14 ±7 days (14d, N = 182) and ≥ 90 days (90d, N = 145) after starting or changing antiplatelet therapy with healthy controls (N = 34). There were no differences in median %RP between the overall CVD patient population at baseline or 14d vs. controls (P ≥ 0.2). However, the median %RP was significantly higher in CVD patients overall at 90d (P = .036), and in the subgroup of patients with "lacunar" TIA/ischemic stroke at baseline (P = .04) and at 90d (P = .01), but not at 14d (P = .06) vs. controls. There were no significant differences in the median %RP between other TIA/stroke subgroups and controls (P ≥ 0.05). Elevated circulating reticulated platelets, as a marker of increased platelet production/turnover, may occur following an ischemic event in a well-phenotyped TIA/ischemic stroke population overall, but may precede symptom onset at least in the subgroup with small vessel occlusion. These data improve our understanding of the profile of reticulated platelets in CVD patients.

Diagnostic and Prognostic Blood Biomarkers in Transient Ischemic Attack and Minor Ischemic Stroke: An Up-To-Date Narrative Review.

INTRODUCTION: Early diagnosis and correct risk stratification in patients with transient ischemic attack (TIA) and minor ischemic stroke (MIS) is crucial for the high rate of subsequent disabling stroke. Although highly improved, diagnosis and prognostication of TIA/MIS patients remain still based on clinical and neuroimaging findings, with some inter-rater variability even among trained neurologists. OBJECTIVES: To provide an up-to-date overview of diagnostic and prognostic blood biomarkers in TIA and MIS patients. MATERIAL AND METHODS: We performed a bibliographic search on PubMed database with last access on July 10th 2021. More than 680 articles were screened and we finally included only primary studies on blood biomarkers. RESULTS: In a narrative fashion, we discussed about blood biomarkers investigated in TIA/MIS patients, including inflammatory, thrombosis, neuronal injury and cardiac analytes, antibodies and microRNAs. Other soluble molecules have been demonstrated to predict the risk of recurrent cerebrovascular events or treatment response in these patients. A rapid point of care assay, combining the determination of different biomarkers, has been developed to improve triage recognition of acute cerebrovascular accidents. CONCLUSIONS: The implementation of blood biomarkers in the clinical management of TIA/MIS could ameliorate urgent identification, risk stratification and individual treatment choice. Large prospective and longitudinal studies, adopting standardized sampling and analytic procedures, are needed to clarify blood biomarkers kinetic and their relationship with TIA and minor stroke etiology.

Homocysteine Level Predicts Response to Dual Antiplatelet in Women With Minor Stroke or Transient Ischemic Attack: Subanalysis of the CHANCE Trial.

OBJECTIVES: To investigate the relationship of homocysteine levels with the efficacy and safety of dual antiplatelet therapy in female and male patients. Approach and Results: The CHANCE trial (Clopidogrel in High-Risk Patients With Acute Nondisabling Cerebrovascular Events) randomized patients with acute minor ischemic stroke or high-risk transient ischemic attack to clopidogrel plus aspirin or aspirin alone from October 1, 2009, to July 30, 2012, in China. A subgroup of 3044 consecutive patients with baseline homocysteine levels from 73 (64%) prespecified clinical sites was analyzed. Participants were grouped by sex. Primary outcome was stroke recurrence within 90 days. Secondary outcomes consisted of composite vascular events and independent living or death. Safety outcome was any bleeding. Cox proportional-hazards models were used to assess the interaction of homocysteine levels with randomized antiplatelet therapy on efficacy and safety outcomes. A significant interaction between homocysteine levels and the randomized antiplatelet therapies was found on recurrent stroke after adjustment for confounding factors in women (P=0.010) but not in men (P=0.595). Compared with aspirin alone, clopidogrel plus aspirin significantly reduced the risk of recurrent stroke in women without elevated homocysteine levels (adjusted hazard ratio, 0.459 [95% CI, 0.271-0.776]; P=0.004). Such benefit disappeared in female patients with increased homocysteine level. No significant interaction on functional outcome or bleeding rate was observed. CONCLUSIONS: Homocysteine could be a potential biomarker to discriminate the effects of dual and single antiplatelet therapy in female patients with minor ischemic stroke or high-risk transient ischemic attack. CLINICAL TRIAL REGISTRATION: URL: http://www.clinicaltrials.gov. Unique identifier: NCT00979589.

Association of serum levels of antibodies against ALDOA and FH4 with transient ischemic attack and cerebral infarction.

BACKGROUND: Ischemic stroke, including transient ischemic attack (TIA) and acute-phase cerebral infarction (aCI), is a serious health problem in the aging society. Thus, this study aimed to identify TIA and aCI biomarkers. METHODS: In 19 patients with TIA, candidate antigens recognized by serum IgG autoantibodies were screened using a human aortic endothelial cell cDNA library. Through amplified luminescent proximity homogeneous assay-linked immunosorbent assay (AlphaLISA), serum antibody levels against the candidate antigens were examined in healthy donor (HD), TIA, and aCI cohorts (n = 285, 92, and 529). The plasma antibody levels in the Japan Public Health Center-based Prospective Cohort Study (1991-1993) were also examined. RESULTS: The candidate antigens were aldolase A (ALDOA) and fumarate hydratase (FH). In AlphaLISA, patients with TIA or aCI had higher anti-ALDOA antibody (ALDOA-Ab) and anti-FH antibody (FH-Ab) levels than the HDs (P < 0.05). In a multivariate logistic regression analysis, the ALDOA-Ab (odds ratio [OR]: 2.46, P = 0.0050) and FH-Ab (OR: 2.49, P = 0.0037) levels were independent predictors of TIA. According to the case-control study, the ALDOA-Ab (OR: 2.50, P < 0.01) and FH-Ab (OR: 2.60, P < 0.01) levels were associated with aCI risk. In a correlation analysis, both ALDOA-Abs and FH-Abs were well associated with hypertension, coronary heart disease, and habitual smoking. These antibody levels also correlated well with maximum intima-media thickness, which reflects atherosclerotic stenosis. CONCLUSIONS: ALDOA-Abs and FH-Abs can be novel potential biomarkers for predicting atherosclerotic TIA and aCI.

Risk factor control after ischemic stroke or transient ischemic attack.

OBJECTIVE: We aimed to estimate the status of risk factor control after ischemic stroke or transient ischemic attack (IS/TIA), and the influence on recurrent stroke in rural communities of northeastern China. METHODS: This population-based, prospective cohort study enrolled adults aged ≥35 years residing in rural northeastern China. We conducted cardiovascular health examinations in 2012-2015 and followed up in 2018 to record any cardiovascular event. Control of risk factors after IS/TIA was determined through a baseline survey. The Cox proportional hazard model was used to evaluate the relationship between uncontrolled risk factors and stroke recurrence. RESULTS: Of the 10,700 participants, 575 were diagnosed with IS/TIA and were included in the analysis. At baseline, the rates of control of risk factors were as follows: fasting plasma glucose (FPG), 81.6%; not currently smoking, 65.7%; and achieving physical activity targets, 61%. Blood pressure (BP), low-density lipoprotein cholesterol (LDL-C), and body mass index (BMI) were poorly controlled (28.3%, 26.3%, and 37.4%, respectively). The rate of stroke recurrence was 12% during a median follow-up of 4.43 years. After adjusting for age, sex, ethnicity, family history of stroke, and current drinking, uncontrolled BP and not achieving physical exercise targets were associated with an increased risk of recurrence (hazard ratios: 2.081, 1.685, respectively; p < .05). Uncontrolled FPG, BMI, or LDL-C and current smoking did not significantly influence recurrent risk (p > .05). CONCLUSIONS: Control of risk factors after IS/TIA needs to be improved in rural communities of northeastern China to prevent recurrence and thus alleviate the public health and economic burden of stroke.

Inhibitory Effects of P2Y12 Receptor Antagonist on PAR1- and PAR4-AP-Induced Platelet Aggregation in Patients with Stroke or TIA.

OBJECTIVES: The inhibitory effects of P2Y12 receptor antagonist on PAR1- and PAR4-activating peptide (AP)-induced platelet aggregation have not been fully elucidated. The present study aimed to investigate the inhibitory effects of P2Y12 receptor antagonist on PAR1- and PAR4-AP-induced platelet aggregation using platelet-rich plasma (PRP) from individuals including patients with stroke or transient ischemic attack (TIA). MATERIALS AND METHODS: PRP was given to 10 healthy individuals pretreated in vitro with cangrelor, then stimulated with adenosine diphosphate (ADP), PAR4-AP, or PAR1-AP. Moreover, 20 patients were enrolled from 148 consecutive patients with acute ischemic stroke or TIA admitted to our institute between December 2017 and April 2019. PRP obtained from each patient before and >7 days after initiation of clopidogrel was similarly stimulated with these agonists. Platelet aggregation was measured using an automatic coagulation analyzer in all participants. RESULTS: In healthy individuals, ADP- and PAR4-AP-induced platelet aggregations were significantly inhibited depending on the cangrelor concentration in vitro, while PAR1-AP-induced platelet aggregation was slightly inhibited. In patients with stroke or TIA, clopidogrel inhibited ADP-induced platelet aggregation at all concentrations, and significantly inhibited PAR4-AP-induced platelet aggregation at 50 µmol/L of PAR4-AP (p<0.05), especially in 5 patients who showed high reactivity to PAR4-AP. PAR1-AP-induced platelet aggregation was also slightly inhibited. CONCLUSIONS: We showed significant inhibitory effects on PAR4-AP-induced platelet aggregation by clopidogrel in patients with stroke or TIA who had high reactivity to PAR4-AP.

Cost-Effectiveness of Using LDL-Direct Versus Lipid-Panel as Part of the Inpatient Stroke Workup.

OBJECTIVE: To investigate whether utilizing a LDL-direct laboratory test rather than a lipid panel to determine LDL-C as part of the inpatient stroke and TIA workup is more cost-effective to the patient and hospital system. A retrospective analysis was conducted on all patients admitted to UCSD La Jolla and Hillcrest Hospital and discharged with a final diagnosis of ischemic stroke or transient ischemic attack between 7/2016 and 6/2019. A cost-analysis was extrapolated based on the current cost of each test as provided by the UCSD hospital billing department as of June 2020. Patients started on a statin, who were not on one prior to admission, were also analyzed to highlight the importance of an accurate LDL-C on management of dyslipidemia. RESULTS: A total of 1245 patients were included in the study with 87% representing Ischemic strokes and 13% transient ischemic attacks. Over the three-year period, a total savings of $77,545 would be achieved if LDL-direct were used in place of a lipid-panel, representing an overall cost savings of 33%. Over the same time-frame, 536 (43%) patients were started on a statin that were not previously on one. CONCLUSIONS: Ordering a LDL-direct test should be considered over a lipid panel to evaluate LDL-C as it may prove to be the most cost effective approach to both the patient and Healthcare system.

Increased Incidence of Ischemic Cerebrovascular Events in Cardiovascular Patients With Elevated Apolipoprotein CIII.

Background and Purpose- Apo CIII (apolipoprotein CIII), a crucial regulator of lipoprotein metabolism, has been associated with increased activity of coagulation factors and thrombin generation and, in turn, with an increased risk of thromboembolic events in both arterial and venous districts. Thus, we hypothesized that it may affect the risk of acute ischemic cerebrovascular events in cardiovascular patients. Methods- We systematically checked medical records and quantified cerebral ischemic events in a cohort of 950 subjects (median age 65 with interquartile range, 55-79 years; 30.7% females) with or without angiographically defined coronary artery disease (CAD: 774 CAD and 176 CAD-free, respectively). All the subjects, enrolled between May 1999 and December 2006, were prospectively followed until death or July 31, 2018. Assessments of complete plasma lipid and apolipoprotein profiles, including Apo A-I, B, CIII, and E, were available for all subjects at enrollment. Results- After a median follow-up of 130 months (interquartile range, 69-189), 95 subjects (10%) suffered ischemic stroke/transient ischemic attack (TIA) events. Stroke/TIA subjects had higher Apo CIII plasma concentration (11.4; interquartile range: 9.3-14.4 mg/dL) at enrollment than those without stroke/TIA (10.4, interquartile range: 8.7-13.0 mg/dL). Subjects with Apo CIII levels above the median value (10.6 mg/dL) exhibited an ≈2-fold increased risk of stroke/TIA, even after adjustment for potential confounders, including sex, age, CAD diagnosis, hypertension, atrial fibrillation, oral anticoagulant treatment, and all plasma lipid parameters (hazard ratio: 2.23 [95% CI, 1.21-4.13]). This result was confirmed in CAD and CAD-free populations, separately, and even by a propensity score matching method, in which 98 CAD and 98 CAD-free subjects were one-to-one matched for all clinical and laboratory characteristics. Conclusions- These findings suggest that a high Apo CIII plasma concentration may predict an increased risk of ischemic stroke/TIA in cardiovascular patients.

Initiation of the ABCD3-I algorithm for expediated evaluation of transient ischemic attack patients in an emergency department.

BACKGROUND: The use of ABCD3-I score for Transient ischemic attack (TIA) evaluation has not been widely investigated in the ED. We aim to determine the performance and cost-effectiveness of an ABCD3-I based pathway for expedited evaluation of TIA patients in the ED. METHODS: We conducted a single-center, pre- and post-intervention study among ED patients with possible TIA. Accrual occurred for seven months before (Oct. 2016-April 2017) and after (Oct. 2017-April 2018) implementing the ABCD3-I algorithm with a five-month wash-in period (May-Sept. 2017). Total ED length of stay (LOS), admissions to the hospital, healthcare cost, and 90-day ED returns with subsequent stroke were analyzed and compared. RESULTS: Pre-implementation and post-implementation cohorts included 143 and 118 patients respectively. A total of 132 (92%) patients were admitted to the hospital in the pre-implementation cohort in comparison to 28 (24%) patients admitted in the post-implementation cohort (p < 0.001) with similar 90-day post-discharge stroke occurrence (2 in pre-implementation versus 1 in post-implementation groups, p > 0.05). The mean ABCD2 scores were 4.5 (1.4) in pre- and 4.1 (1.3) in post-implementation cohorts (p = 0.01). The mean ABCD3-I scores were 4.5 (1.8) in post-implementation cohorts. Total ED LOS was 310 min (201, 420) in pre- and 275 min (222, 342) in post-implementation cohorts (p > 0.05). Utilization of the ABCD3-I algorithm saved an average of over 40% of total healthcare cost per patient in the post-implementation cohort. CONCLUSIONS: The initiation of an ABCD3-I based pathway for TIA evaluation in the ED significantly decreased hospital admissions and cost with similar 90-day neurological outcomes.

High on-clopidogrel platelet reactivity in ischaemic stroke or transient ischaemic attack: Systematic review and meta-analysis.

OBJECTIVES: To assess the prevalence of high on-clopidogrel platelet reactivity (HCPR) in patients with ischaemic stroke or transient ischaemic attack (IS/TIA), their outcome and genetic basis of on-treatment response variability in IS/TIA patients. METHODS: We conducted a comprehensive search of PubMed and EMBASE from their inceptions to March 9, 2019. Studies that reported absolute numbers/percentages of HCRP at any time point after IS/TIA onset evaluated with any type of platelet function tests, clinical outcomes and genotyping data were included. RESULTS: Among 21 studies of 4312 IS/TIA patients treated with clopidogrel, the pooled prevalence of HCPR was 28% (95%CI: 24-32%; high heterogeneity: I2 = 88.2%, p < 0.001). Heterogeneity degree diminished across groups defined by the HCPR testing method. Clopidogrel non-responder IS/TIA patients had poorer outcome compared to responders (RR = 2.09, 95%CI: 1.61-2.70; p = 0.036; low heterogeneity across studies: I2 = 27.4%, p = 0.210). IS/TIA carriers of CYP2C19*2 or CYP2C19*3 loss of function alleles had a higher risk of HCPR compared to wild type (RR = 1.69, 95%CI: 1.47-1.95; p < 0.001; I2 = 0.01%, p = 0.475). CONCLUSIONS: This systematic review shows a high prevalence of clopidogrel resistance in IS/TIA and poor outcome in these patients. CYP2C19 polymorphisms may potentially influence clopidogrel resistance.

Prediction of Persistent Impaired Glucose Tolerance in Patients with Minor Ischemic Stroke or Transient Ischemic Attack.

BACKGROUND: Impaired glucose tolerance (IGT) in patients with ischemic stroke can return to normal, reflecting an acute stress response, or persist. Persistent IGT is associated with an increased risk of recurrent stroke, other cardiovascular diseases and unfavorable outcome after stroke. We aim to validate our previously developed model to identify patients at risk of persistent IGT in an independent data set, and, if necessary, update the model. METHODS: The validation data set consisted of 239 nondiabetic patients with a minor ischemic stroke or TIA and IGT in the acute phase (2-hour post-load glucose levels between 7.8 and 11.0 mmol/l). The outcome was persistent versus normalized IGT, based on repeated oral glucose tolerance test after a median of 46 days. The discriminative ability of the original model was assessed with the area under the ROC curve (AUC). The updated model was internally validated with bootstrap resampling and cross-validated in the development population of the original model. RESULTS: One-hundred eighteen of 239 (49%) patients had persistent IGT. The original model, with the predictors age, current smoking, statin use, triglyceride, hypertension, history of cardiovascular diseases, body mass index (BMI), fasting plasma glucose performed poorly (AUC .60). The newly developed model included only BMI, hypertension, statin use, atrial fibrillation, 2-hour post-load glucose levels, HbA1c, large artery atherosclerosis, and predicted persistent IGT more accurately (internally validated AUC 0.66, externally validated AUC .71). CONCLUSIONS: This prediction model with simple clinical variables can be used to predict persistent IGT in patients with IGT directly after minor stroke or TIA, and may be useful to optimize secondary prevention by early identification of patients with disturbed glucose metabolism.

Myocardial injury in transient global amnesia: a case-control study.

BACKGROUND AND PURPOSE: Elevation of cardiac troponin (cTn), a sensitive biomarker of myocardial injury, is frequently observed in severe acute neurological disorders. Case reports suggest that cardiac dysfunction may also occur in patients with transient global amnesia (TGA). Until now, no study has systematically assessed this phenomenon. METHODS: We performed a case-control study using data of consecutive patients presenting with TGA from 2010 to 2015. Multiple logistic regression analysis accounting for age, sex and cardiovascular risk factors was performed to compare the likelihood of myocardial injury [defined as elevation of cTn > 99th percentile (≥14 ng/L); highly sensitive cardiac troponin T assay] in TGA with three reference groups: migraine with aura, vestibular neuritis and transient ischaemic attack (TIA). RESULTS: Cardiac troponin elevation occurred in 28 (25%) of 113 patients with TGA. Patients with TGA with cTn elevation were significantly older, more likely to be female and had higher blood pressure on admission compared with those without. The likelihood of myocardial injury following TGA was at least more than twofold higher compared with all three reference groups [adjusted odds ratio, 5.5; 95% confidence interval (CI), 1.2-26.4, compared with migraine with aura; adjusted odds ratio, 2.2; 95% CI, 1.2-4.4, compared with vestibular neuritis; adjusted odds ratio, 2.3; 95% CI, 1.3-4.2, compared with TIA]. CONCLUSIONS: One out of four patients with TGA had evidence of myocardial injury as assessed by highly sensitive cTn assays. The likelihood of myocardial injury associated with TGA was even higher than in TIA patients with a more pronounced cardiovascular risk profile. Our findings suggest the presence of a TGA-related disturbance of brain-heart interaction that deserves further investigation.

Oxidative lipoprotein markers predict poor functional outcome in patients with minor stroke or transient ischaemic attack.

BACKGROUND AND PURPOSE: Oxidative stress plays an important role in acute ischaemic stroke. However, the association of oxidative lipoprotein markers, including oxidized low-density lipoprotein (oxLDL), oxLDL:high-density lipoprotein (HDL) and oxLDL:low-density lipoprotein (LDL), with functional outcome of minor stroke or transient ischaemic attack (TIA) remains unclear. We aimed to investigate the association between oxidative lipoprotein markers and poor functional outcome in patients with minor stroke or TIA. METHODS: All patients with minor stroke or TIA were recruited from the Clopidogrel in High-Risk Patients With Acute Non-Disabling Cerebrovascular Events (CHANCE) trial. The poor functional outcome included modified Rankin Scale (mRS) score 2-6 and 3-6 at 90-day and 12-month follow-up. Multivariate logistic regression was used to investigate the associations of oxLDL, oxLDL:HDL and oxLDL:LDL with poor functional outcome. RESULTS: Among 3019 patients included in this study, the median (interquartile range) oxLDL, oxLDL:HDL and oxLDL:LDL were 13.96 (6.65-28.81), 4.52 (2.08-9.32) and 11.73 (5.27-24.85) µg/dL, respectively. After adjusted for confounding factors, patients in the highest oxLDL quartile had a higher proportion of mRS score 2-6 at 90 days [hazard ratio (HR), 1.78; 95% confidence interval (CI), 1.26-2.52] and 12 months (HR, 1.42; 95% CI, 1.01-1.99), and mRS score 3-6 at 90 days (HR, 1.98; 95% CI, 1.29-3.04) and 12 months (HR, 1.77; 95% CI, 1.09-2.89) when compared with the lowest oxLDL quartile (P < 0.05). Similar results were found for oxLDL:HDL and oxLDL:LDL. CONCLUSIONS: Higher levels of oxidative lipoprotein markers are independent predictors of poor functional outcome in patients with minor stroke or TIA at 90 days and 12 months.

Candidate Biomarkers for the Diagnosis of Transient Ischemic Attack: A Systematic Review.

BACKGROUND AND PURPOSE: A rapid serum biomarker that confirms or rules out a transient ischemic attack (TIA) would be of great value in clinical practice. We aimed to systematically review current evidence for the diagnostic accuracy of blood biomarkers in the early diagnosis of TIA. METHODS: This is a systematic review with quality appraisal of individual studies using the QUADAS-2 tool. MEDLINE and EMBASE databases were searched up to May 1, 2017, to select primary diagnostic accuracy studies evaluating potential biomarkers in blood for the diagnosis of TIA or ischemic stroke. RESULTS: Of 4,215 studies retrieved, 78 met our eligibility criteria. Forty-five studies restricted their population to ischemic stroke patients, 32 included both TIA and ischemic stroke patients, and only one study was restricted to TIA patients. In total 62/78 (79.5%) studies had a case-control design comparing TIA or stroke patients with healthy subjects. Overall, 125 single biomarkers and 5 biomarker panels were studied, with a median number of participants per study of 92.0 (interquartile range 44.8-144.5), varying from 8 to 915. Sufficient information to extract 2 × 2 tables was available for 35 (44.9%) articles, and for 60 (48.0 %) biomarkers. Several markers, such as NR2A/B (antibodies), Parkinson 7, nucleoside diphosphate kinase A, ubiquitin fusion degradation protein-1, and heart-type fatty acid binding protein, have shown moderate to high diagnostic accuracy in multiple studies. CONCLUSIONS: Although the methodological quality of studies evaluating biomarkers of brain ischemia was poor, several biomarkers have shown the potential to detect transient brain ischemia in an early phase. Diagnostic accuracy studies in suspected cases of TIA are needed to determine their true clinical value.

Clopidogrel and aspirin after ischemic stroke or transient ischemic attack: an updated systematic review and meta-analysis of randomized clinical trials.

Recurrent stroke is common immediately following a transient ischemic attack (TIA) or ischemic stroke. Dual antiplatelet therapy (DAPT) with clopidogrel and aspirin may provide greater protection against subsequent stroke than monotherapy. Electronic databases were searched for randomized clinical trials (RCTs) comparing DAPT with monotherapy in ischemic stroke/TIA. Sixteen RCTs with a total of 29,032 patients were included. Compared with monotherapy, DAPT was associated with significantly lower rates of any stroke (risk ratio [RR] 0.80; 95% confidence interval [CI] 0.72-0.89) and ischemic stroke (RR 0.75; 95% CI 0.66-0.85) during any follow-up period. Although significant increases in intracranial bleeding (RR 1.55; 95% CI 1.20-2.01) and major bleeding (RR 1.90; 95% CI 1.33-2.72) were associated with DAPT, especially with long-term follow-up, the number needed to harm was 258 and 113, respectively. Nevertheless, short-duration DAPT (≤ 1 month) started during the early acute ischemic phase was associated with less bleeding than longer DAPT and greater reduction of recurrent strokes compared with monotherapy. In contrast, long DAPT and DAPT started later after the index event (≥ 1 month) were associated with similar rates of any stroke and increased risks of bleeding compared with monotherapy. Other clinical outcomes were essentially similar between the two groups and included recurrent TIA (RR 0.88; 95% CI 0.72-1.07), myocardial infarction (RR 1.04; 95% CI 0.84-1.29), vascular death (RR 0.99; 95% CI 0.82-1.19), and any death (RR 1.12; 95% CI 0.88-1.42). Similar findings were observed in patients who presented with minor stroke/TIA. Conclusions: Among patients who presented with ischemic stroke/TIA, short-course clopidogrel plus aspirin immediately following the index event appears to be more effective than and as safe as monotherapy for secondary stroke prevention.