Untargeted metabolomics predicts the functional outcome of ischemic stroke.

BACKGROUND/PURPOSE: Metabolites in blood have been found associated with the occurrence of vascular diseases, but its role in the functional recovery of stroke is unclear. The aim of this study is to investigate whether the untargeted metabolomics at the acute stage of ischemic stroke is able to predict functional recovery. METHODS: One hundred and fifty patients with acute ischemic stroke were recruited and followed up for 3 months. Fasting blood samples within 7 days of stroke were obtained, liquid chromatography and mass spectrometry were applied to identify outcome-associated metabolites. The patients' clinical characteristics and identified metabolites were included for constructing the outcome prediction model using machine learning approaches. RESULTS: By using multivariate analysis, 220 differentially expressed metabolites (DEMs) were discovered between patients with favorable outcomes (modified Rankin Scale, mRS ≤ 2 at 3 months, n = 77) and unfavorable outcomes (mRS ≥ 3 at 3 months, n = 73). After feature selection, 63 DEMs were chosen for constructing the outcome prediction model. The predictive accuracy was below 0.65 when including patients' clinical characteristics, and could reach 0.80 when including patients' clinical characteristics and 63 selected DEMs. The functional enrichment analysis identified platelet activating factor (PAF) as the strongest outcome-associated metabolite, which involved in proinflammatory mediators release, arachidonic acid metabolism, eosinophil degranulation, and production of reactive oxygen species. CONCLUSION: Metabolomics is a potential method to explore the blood biomarkers of acute ischemic stroke. The patients with unfavorable outcomes had a lower PAF level compared to those with favorable outcomes.

Plasma Amyloid Beta and Tau Levels Are Predictors of Post-stroke Cognitive Impairment: A Longitudinal Study.

Objectives: Post-stroke cognitive impairment (PSCI) is a common disease that may occur within 3 months after a stroke or even later. However, the mechanism of PSCI development is unclear. The present study investigated whether the levels of plasma amyloid beta-42 (Aß42) and tau are associated with the onset of PSCI. Methods: Fifty-five patients admitted within 7 days of acute ischemic stroke were enrolled and followed up for 1 year. Montreal Cognitive Assessment (MoCA) was administered at 3 months and 1 year, and plasma Aß42 and tau levels were determined using an ultrasensitive immunoassay (immunomagnetic reduction) within 7 days of the stroke event and 3 months later. Results: In this study, 13 of 55 patients developed PSCI (MoCA score <23) at 3 months. Seven patients with PSCI at 3 months recovered to a cognitively normal state at 1 year, whereas seven cognitively normal patients developed PSCI at 1 year. The patients with PSCI at 1 year had a higher incidence of cognitive function deterioration between 3 months and 1 year compared with those without PSCI at 1 year. Plasma Aß42 and tau levels at 3 months were lower in the patients with PSCI at 1 year than in those without PSCI (Aß42: 15.1 vs. 17.2 pg/mL, P = 0.013; tau: 16.7 vs. 19.9 pg/mL, P = 0.018). Low education levels and pre-existing white matter disease were the most significant predictors of PSCI at 3 months, and poor cognitive performance at 3 months and low plasma Aß42 and tau levels at 3 months were the most significant predictors of PSCI at 1 year. Conclusion: The pathogenesis of PSCI is complex and changes with time. Ischemia-induced Aß42/tau pathology might be involved in PSCI development.

Prevalence and clinical characteristics of stroke patients with p.R544C NOTCH3 mutation in Taiwan.

Objective: Features of cerebral autosomal dominant arteriopathy with subcortical infarct and leukoencephalopathy ( CADASIL) caused by NOTCH3 mutations vary between ethnicities and regions. In Taiwan, more than 70% of CADASIL patients carry the mutation hot spot of p.R544C. We investigated the prevalence of NOTCH3 p.R544C mutation in stroke patients in Taiwan. Methods: This prospective, multicenter study recruited acute stroke patients within 10 days of symptom onset. The p.R544C mutation was identified by polymerase chain reaction with confronting two-pair primers and sequencing. Clinical parameters, vascular risk factors, stroke subtypes, and stroke outcomes were analyzed. Results: Of the 1970 stroke patients (mean age 61.1 ± 13.6 years, male 69.5%) included, 1705 (86.5%) had ischemic stroke and 265 (13.5%) had intracerebral hemorrhage. The prevalence of p.R544C in the study population was 2.8% (95% confidence interval [CI] = 2.1-3.5%). The prevalence was highest in patients with small vessel occlusion type of ischemic stroke (5.6%), followed by intracerebral hemorrhage (5.3%), and infarct of undetermined etiology (2.7%), and was low in patients with cardioembolism (0.8%) and large artery atherosclerosis (0.7%). All p.R544C patients with intracerebral hemorrhage were nonlobar hemorrhage. Sibling history of stroke (odds ratio [OR] = 4.50, 95% CI = 1.67-12.14 in ischemic stroke; OR = 6.03, 95% CI = 1.03-35.47 in intracerebral hemorrhage, respectively) and small vessel occlusion (OR, 4.03, 95% CI, 1.26-12.92) were significantly associated with p.R544C. Interpretation: p.R544C NOTCH3 mutation is underdiagnosed in stroke patients in Taiwan, especially in those with small vessel occlusion and sibling history of stroke.

Rheumatoid arthritis significantly increased recurrence risk after ischemic stroke/transient ischemic attack.

The effect of RA on recurrent stroke is unknown. Therefore, we examined effects of rheumatoid arthritis (RA) on risk of stroke recurrence and investigated the interaction between RA and traditional cardiovascular risk factors on recurrence risk after ischemic stroke (IS) or transient ischemic attack (TIA). Of 3190 patients with IS or TIA recruited in this cohort study, 638 were comorbid with RA and 2552 without RA. Stroke recurrence, RA, lifestyle, lipid variables and other comorbidities were identified through linkage between a nationwide stroke database in Taiwan and the National Health Insurance claims database. Cox proportional hazard models with competing risk adjustment were used to evaluate the relationship between RA and recurrent stroke. Patients with RA showed a significantly increased risk of recurrent stroke, particular in recurrent IS/TIA. The increased risk of recurrent IS/TIA in RA patients may through the changes of triglycerides (TG)/high-density lipoprotein cholesterol (HDL-C) ratio. A positive additive interaction was observed between RA and current smoking on the risk of recurrent IS/TIA. Significantly increased risks for recurrent IS/TIA were observed among RA patients who smoked > 40 years or those who smoked > 20 cigarettes/day. This study provides the first evidence that RA significantly increased recurrence IS/TIA risk. The changes of TG/HDL-C ratio may play some roles in the recurrence IS/TIA risk in RA patients. In addition, our results suggest that smoking increases the risk of recurrent IS/TIA in RA patients and reinforces the need for aggressive smoking cessation efforts in RA patients.

The effect of rheumatoid arthritis on the risk of cerebrovascular disease and coronary artery disease in young adults.

BACKGROUND: Only a few studies have investigated the affect of rheumatoid arthritis (RA) on the risk of cerebrovascular disease (CVD)/coronary artery disease (CAD) in young adults. This study, therefore, examined the association between RA and the risk of CVD/CAD in young adults and the interaction effects between cardiovascular risk factors and RA on the risk of CVD/CAD. METHODS: Data regarding 52,840 subjects (10,568 patients with RA and 42,272 age-, sex-, urbanization-, and income-matched non-RA controls) were collected from the National Health Insurance Research Database (NHIRD) in 2006. All subjects were followed until a CVD or CAD diagnosis, or death, or December 31, 2011. The hazard ratios (HRs) of CVD/CAD were estimated using Cox proportional hazard models. The interaction effects between cardiovascular risk factors and RA on the risk of CVD/CAD were assessed using additive and multiplicative models. RESULTS: RA increased the risk of CVD/CAD in young adults, especially those at risk of ischemic stroke (adjusted HR, 3.48; 95% confidence interval (CI), 2.16-5.61). Even without comorbidity at baseline, patients with RA still had a 2.35-fold greater risk of CVD/CAD relative to those without RA. RA and hypertension interacted positively on the risk of CVD/CAD. The highest CVD/CAD risk was found in patients with RA and hypertension (HR, 9.08; 95% CI, 7.22-11.41) relative to subjects without RA and hypertension. CONCLUSION: RA is an independent risk factor for CVD/CAD in young adults. The government should develop policies for preventing early onset hypertension to reduce the incidence of CVD/CAD among young patients with RA.

Effect on Risk of Stroke and Acute Myocardial Infarction of Nonselective Nonsteroidal Anti-Inflammatory Drugs in Patients With Rheumatoid Arthritis.

There are still debates on the association of increased cardiovascular risk with the use of nonsteroidal anti-inflammatory drugs (NSAIDs) in patients with rheumatoid arthritis (RA) because of inconsistent results. Therefore, our study aims to evaluate the transient effects of selective and nonselective NSAIDs on the risk of stroke and acute myocardial infarction (AMI) in patients with RA. We conducted a case-crossover study of 5,921 stroke or AMI patients with co-morbidity of RA. All cases were identified from the Taiwan National Health Insurance Database between January 1, 2006, and December 31, 2011, according to the International Classification of Diseases, 9th Revision and Clinical Modification diagnosis codes from inpatient claims. The index date was defined as the date of hospitalization for stroke or AMI. Exposure to NSAIDs was compared during a case period (1 to 30 days before the index date) with a control period (91 to 120 days before the index date). The adjusted odds ratios (ORs) of stroke and AMI were estimated using conditional logistic regression models. Our results showed that overall NSAIDs use increased the risk of stroke by 1.40-fold (95% confidence interval [CI] 1.25 to 1.56) and risk of AMI by 1.73-fold (95% CI 1.29 to 2.32). After classifying NSAIDs into selective and nonselective groups, only nonselective NSAIDs use significantly increased the risks of stroke (adjusted OR 1.39; 95% CI 1.25 to 1.55) and AMI (adjusted OR 1.82; 95% CI 1.37 to 2.41), respectively. In conclusion, nonselective NSAIDs were associated with an increased risk of both stroke and AMI in patients with RA.

Associations of estradiol levels and genetic polymorphisms of inflammatory genes with the risk of ischemic stroke.

BACKGROUND: Estrogen plays an important role as an anti-inflammatory and neuroprotective agent in ischemic stroke. In this study, we analyzed the effect of a polygenic risk score (PRS) constructed using inflammatory genes and estradiol levels on the risk of ischemic stroke. METHODS: This case-control study was conducted with 624 ischemic stroke patients and 624 age- and gender-matched controls. The PRS estimated the polygenic contribution of inflammatory genes from ischemic stroke susceptibility loci. Estradiol levels were measured using a radioimmunoassay. High and low estradiol levels were defined according to the log-transformed median estradiol levels in female and male controls. RESULTS: Subjects in the fourth quartile of the PRS had a significant 1.57-fold risk of ischemic stroke (95% confidence interval [CI], 1.12 ~ 2.19), after adjusting for covariates compared to individuals in the lowest quartile. Compared to individuals with high estradiol levels and a low PRS as the reference group, those exposed to low estradiol levels and a high PRS had an increased risk of ischemic stroke (odds ratio, 3.35; 95% CI, 1.79 ~ 6.28). Similar results were also observed in males when the analysis was stratified by gender. CONCLUSIONS: Our data suggest that the PRS can be useful in evaluating a high risk of ischemic stroke among patients, especially those exposed to low estradiol levels.

Comparison of admission random glucose, fasting glucose, and glycated hemoglobin in predicting the neurological outcome of acute ischemic stroke: a retrospective study.

BACKGROUND: Hyperglycemia is a known predictor of negative outcomes in stroke. Several glycemic measures, including admission random glucose, fasting glucose, and glycated hemoglobin (HbA1c), have been associated with bad neurological outcomes in acute ischemic stroke, particularly in nondiabetic patients. However, the predictive power of these glycemic measures is yet to be investigated. METHODS: This retrospective study enrolled 484 patients with acute ischemic stroke from January 2009 to March 2013, and complete records of initial stroke severity, neurological outcomes at three months, and glycemic measures were evaluated. We examined the predictive power of admission random glucose, fasting glucose, and HbA1c for neurological outcomes in acute ischemic stroke. Furthermore, subgroup analyses of nondiabetic patients and patients with diabetes were performed separately. RESULTS: Receiver operating characteristic (ROC) analysis revealed that admission random glucose and fasting glucose were significant predictors of poor neurological outcomes, whereas HbA1c was not (areas under the ROC curve (AUCs): admission random glucose = 0.564, p = 0.026; fasting glucose = 0.598, p = 0.001; HbA1c = 0.510, p = 0.742). Subgroup analyses of nondiabetic patients and those with diabetes revealed that only fasting glucose predicts neurological outcomes in patients with diabetes, and the AUCs of these three glycemic measures did not differ between the two groups. A multivariate logistic regression analysis of the study patients indicated that only age, initial stroke severity, and fasting glucose were independent predictors of poor neurological outcomes, whereas admission random glucose and HbA1c were not (adjusted odds ratio: admission random glucose = 1.002, p = 0.228; fasting glucose = 1.005, p = 0.039; HbA1c = 1.160, p = 0.076). Furthermore, subgroup multivariate logistic regression analyses of nondiabetic patients and those with diabetes indicated that none of the three glycemic measures were associated with poor neurological outcomes. DISCUSSION: Fasting glucose is an independent predictor of poor neurological outcomes in patients with acute ischemic stroke and had greater predictive power than that of admission random glucose and HbA1c. The predictive power of glycemic measures for poor neurological outcomes did not differ significantly between the nondiabetic patients and those with diabetes.

Risk factors correlated with risk of insulin resistance using homeostasis model assessment in adolescents in Taiwan.

The study aims to discover risk factors significantly correlated with insulin resistance among adolescents in Taiwan. A total of 339 study subjects were recruited in this cross-sectional study. A self-administered questionnaire and physical examinations including anthropometrics and biochemistry profiles were collected. Insulin resistance was assessed using homeostasis model assessment for insulin resistance (HOMA-IR). Study subjects had a significantly increased risk of IR for those with abnormal level of body mass index (odds ratio [OR] = 3.54; 95% confidence interval [CI] = 1.81-6.91), body fat (OR = 2.71; 95% CI = 1.25-5.88), and waist circumference (OR = 25.04; 95% CI = 2.93-214.14) when compared with those who have normal values. Furthermore, a significantly joint effect of 10.86-fold risk for HOMA-IR abnormality among body fat, body mass index, and systolic blood pressure was observed. The identification of risk factors significantly correlated with IR will be important to prevent metabolic syndrome-related diseases and complications for adolescents in their future life.