Fibrinogen independently predicts the development of ischemic stroke in a Taiwanese population: CVDFACTS study

The potential link between acromegaly and risk of acute ischemic stroke in patients with pituitary adenoma: a new perspective

Acromegaly is an endocrine disorder due to the excess production of growth hormone (GH) from the anterior pituitary gland after closed epiphyseal growth plates. Acromegaly is mainly caused by benign GH-secreting pituitary adenoma. Acute ischemic stroke (AIS) is one of the most common cardiovascular complications. It ranks second after ischemic heart disease (IHD) as a cause of disability and death in high-income countries globally. Thus, this review aimed to elucidate the possible link between acromegaly and the development of AIS. The local effects of acromegaly in the development of AIS are related to the development of pituitary adenoma and associated surgical and radiotherapies. Pituitary adenoma triggers the development of AIS through different mechanisms, particularly aneurysmal formation, associated thrombosis, and alteration of cerebral microcirculation. Cardiovascular complications and mortality were higher in patients with pituitary adenoma. The systemic effect of acromegaly-induced cardio-metabolic disorders may increase the risk for the development of AIS. Additionally, acromegaly contributes to the development of endothelial dysfunction (ED), inflammatory and oxidative stress, and induction of thrombosis that increases the risk for the development of AIS. Moreover, activated signaling pathways, including activator of transcription 3 (STAT3), nuclear factor kappa B (NF-κB), nod-like receptor pyrin 3 (NLRP3) inflammasome, and mitogen-activated protein kinase (MAPK) in acromegaly may induce systemic inflammation with the development of cardiovascular complications mainly AIS. Taken together, acromegaly triggers the development of AIS through local and systemic effects by inducing the formation of a cerebral vessel aneurysm, the release of pro-inflammatory cytokines, the development of oxidative stress, ED, and thrombosis correspondingly.

Whole Blood Viscosity and Cerebral Blood Flow in Acute Ischemic Stroke

Existing effective treatments for ischemic stroke restore blood supply to the ischemic region using thrombolysis or mechanical removal of clot. However, it is increasingly recognized that successful removal of occlusive thrombus from the large artery-recanalization, may not always be accompanied by successful restoration of blood flow to the downstream tissues-reperfusion. Ultimately, brain tissue survival depends on cerebral perfusion, and a functioning microcirculation. Because capillary diameter is often equal to or smaller than an erythrocyte, microcirculation is largely dependent on erythrocyte rheological (hemorheological) factors such as whole blood viscosity (WBV). Several studies in the past have demonstrated elevated WBV in stroke compared with healthy controls. Also, elevated WBV has shown to be an independent risk factor for stroke. Elevated WBV leads to endothelial dysfunction, decreases nitric oxide-dependent flow-mediated vasodilation, and promotes hemostatic alterations/thrombosis, all leading to microcirculation sludging. Compromised microcirculation further leads to decreased cerebral perfusion. Hence, modulating WBV through pharmacological agents might be beneficial to improve cerebral perfusion in stroke. This review discusses the effect of elevated WBV on endothelial function, hemostatic alterations, and thrombosis leading to reduced cerebral perfusion in stroke.

Prevalence and predictive modeling of undiagnosed diabetes and impaired fasting glucose in Taiwan: a Taiwan Biobank study

INTRODUCTION

We investigated the prevalence of undiagnosed diabetes and impaired fasting glucose (IFG) in individuals without known diabetes in Taiwan and developed a risk prediction model for identifying undiagnosed diabetes and IFG.

RESEARCH DESIGN AND METHODS

Using data from a large population-based Taiwan Biobank study linked with the National Health Insurance Research Database, we estimated the standardized prevalence of undiagnosed diabetes and IFG between 2012 and 2020. We used the forward continuation ratio model with the Lasso penalty, modeling undiagnosed diabetes, IFG, and healthy reference group (individuals without diabetes or IFG) as three ordinal outcomes, to identify the risk factors and construct the prediction model. Two models were created: Model 1 predicts undiagnosed diabetes, IFG_110 (ie, fasting glucose between 110 mg/dL and 125 mg/dL), and the healthy reference group, while Model 2 predicts undiagnosed diabetes, IFG_100 (ie, fasting glucose between 100 mg/dL and 125 mg/dL), and the healthy reference group.

RESULTS

The standardized prevalence of undiagnosed diabetes for 2012-2014, 2015-2016, 2017-2018, and 2019-2020 was 1.11%, 0.99%, 1.16%, and 0.99%, respectively. For these periods, the standardized prevalence of IFG_110 and IFG_100 was 4.49%, 3.73%, 4.30%, and 4.66% and 21.0%, 18.26%, 20.16%, and 21.08%, respectively. Significant risk prediction factors were age, body mass index, waist to hip ratio, education level, personal monthly income, betel nut chewing, self-reported hypertension, and family history of diabetes. The area under the curve (AUC) for predicting undiagnosed diabetes in Models 1 and 2 was 80.39% and 77.87%, respectively. The AUC for predicting undiagnosed diabetes or IFG in Models 1 and 2 was 78.25% and 74.39%, respectively.

CONCLUSIONS

Our results showed the changes in the prevalence of undiagnosed diabetes and IFG. The identified risk factors and the prediction models could be helpful in identifying individuals with undiagnosed diabetes or individuals with a high risk of developing diabetes in Taiwan.

Fibrinogen as a Predictor of Early Neurological Deterioration in Acute Ischemic Stroke - Evidence From the Indian Population

Background

Early neurological deterioration (END) is a common occurrence in ischemic stroke and contributes significantly to poor outcomes. Although multiple factors that predict END have already been identified, the role of fibrinogen - a key component of the coagulation pathway, is controversial.

Objective

To assess the role of fibrinogen in predicting END and poor hospital outcome in patients with acute ischemic stroke.

Design

Single-centre prospective observational study.

Methods

141 patients with acute ischemic stroke were analyzed in this prospective observational study from a single tertiary-care hospital in East India. END was defined as a worsening of ≥2 points on the National Institutes of Health Stroke Scale (NIHSS) within 7 days of admission. A score of 3-5 on the Modified Rankin Scale (mRS), a stroke recurrence event or death during hospital stay was considered poor hospital outcome. We performed univariate analysis using age, sex, body-mass index (BMI), hypertension, diabetes, NIHSS scores, stroke etiology, blood glucose and lipid parameters and plasma fibrinogen to develop a logistic regression model to establish the independent predictors of END and poor outcome.

Results

Age (Odds Ratio (OR) 1.034 [95% CI 1.001-1.069], P = .046), NIHSS score at admission (OR 1.152 [95% CI 1.070-1.240], P < .001) and fibrinogen (OR 1.011 [95%CI 1.006-1.015], P < .001) were independent predictors of END in patients with acute ischemic stroke. Factors independently associated with poor outcome were NIHSS score at admission (OR 1.257 [95% CI 1.150-1.357], P < .001), fasting plasma glucose (OR 1.007 [95% CI 1.001-1.013], P = .020), and fibrinogen [OR 1.004 [95% CI 1.000-1.007], P = .038).

Conclusion

The significant role of fibrinogen in determining neurological worsening and subsequent poor outcomes in patients with acute ischemic stroke may help in early prognostication and guided therapeutic interventions.

Exploring the hub mechanisms of ischemic stroke based on protein-protein interaction networks related to ischemic stroke and inflammatory bowel disease

Ischemic stroke is highly concerning because it often leads to severe long-term neurological disability. Among clinical trials, ischemic stroke and inflammatory bowel disease interactions have been increasingly reported in recent years. Therefore, using bioinformatics approaches to explore novel protein interactions between them is of interest. We performed this exploratory analysis by using bioinformatics tools such as string to analyze gene data downloaded from NHGRI-GWAS data related to ischemic stroke and inflammatory bowel disease. We constructed a prospective protein interaction network for ischemic stroke and inflammatory bowel disease, identifying cytokine and interleukin-related signaling pathways, Spliceosome, Ubiquitin-Proteasome System (UPS), Thrombus, and Anticoagulation pathways as the crucial biological mechanisms of the network. Furthermore, we also used data-independent acquisition mass spectrometry (DIA-MS) to detect differential protein expression in eight samples, which also suggested that immune system, signal transduction, and hemostasis-related pathways are key signaling pathways. These findings may provide a basis for understanding the interaction between these two states and exploring possible molecular and therapeutic studies in the future.

Associations between fibrinogen levels and the risk of cardiovascular disease and all-cause death: a cohort study from the Chin-Shan community in Taiwan

OBJECTIVES

Although several studies have investigated the association between fibrinogen level and the risk of cardiovascular disease (CVD), few studies have been conducted in Asia.

SETTING

We conducted a community-based prospective cohort study in the Chin-Shan community, Taiwan.

PARTICIPANTS

A total of 2222 participants (54.6±11.9 years, 53.4% women, and 22.4 years of follow-up) who underwent plasma fibrinogen measurements and were without CVD at baseline were recruited, among which 735 participants with available C reactive protein (CRP) were included in the joint analysis of the association of fibrinogen and CRP levels with the risk of CVD.

PRIMARY AND SECONDARY OUTCOME MEASURES

Fibrinogen and CRP levels were measured by clotting and high-sensitivity immunoturbidimetric assays, respectively. The study outcomes were CVD events and all-cause death. Our definition of CVD included both coronary artery disease (CAD) and stroke cases. Cox proportional hazards regression models were used to estimate the HRs and 95% CIs.

RESULTS

Compared with the lowest quartile, participants with higher fibrinogen levels tended to have a higher risk of CAD (adjusted HR for the highest quartile=1.48 (95% CI 0.90 to 2.44); test for trend p=0.037) regardless of CRP level (adjusted HR=2.12 (95% CI 1.24 to 3.63) and 2.17 (95% CI 1.06 to 4.44) for high fibrinogen/low CRP and high fibrinogen/high CRP, respectively). The association was not observed for stroke (adjusted HR for the highest quartile=0.99 (95% CI 0.62 to 1.60); test for trend p=0.99) and was only observed for all-cause death among participants <65 years of age (adjusted HR for the highest quartile=1.47 (95% CI 1.11 to 1.95); test for trend p=0.004).

CONCLUSIONS

Fibrinogen may be a potential risk factor for CAD but not for stroke. Further studies are necessary to clarify the differences in the role of fibrinogen levels on the risk of CVD between Asian and Western countries.

Associations Between Cerebral Vasoreactivity and Cognitive Function in the Middle-Aged Non-Demented Population

Background: Increasing evidence shows early vascular dysregulation in the pathophysiology of Alzheimer’s disease (AD) in elderly population. Objective: We wondered about the relationship between vascular health and cognitive performance in middle-aged adults. The present study aims to evaluate whether and which brain vascular hemodynamic parameters are associated with cognitive functions in a middle-aged, non-demented population. Methods: We recruited 490 middle-aged community-based participants (30–60 years). Transcranial color-coded sonography was used to measure cerebral vascular hemodynamics, including mean flow velocity, pulsatility index, and breath-holding index (BHI) in the middle cerebral arteries (MCAs). Cognitive functions were assessed using the Montreal Cognitive Assessment (MoCA). A multivariate linear regression model was used to determine the association between the MoCA scores and each intracranial hemodynamic parameter. Results: In 369 participants (median age 52 years [IQR 47–56], 48.8% men) with robust acoustic windows, the factors related to poorer MoCA scores were older age, less education extent, and the habitats of cigarette smoking or alcohol consumption. Multivariate analyses did not show a significant association between any intracranial hemodynamic parameters in both MCAs and MoCA scores in the total study population. Left MCA BHI was found to be significantly and independently correlated with the MoCA scores only in people aged 55–60 years (n = 111, B = 0.70, 95% confidence interval, 0.13–1.26, p = 0.017), however, not in people younger than 55 years. Conclusion: Our results emphasize the role of neurovascular abnormalities in the early pathophysiology of cognitive impairment and suggest cerebral vasoreactivity as the earliest detectable cognition-associated hemodynamic parameter.

Impact of Helicobacter pylori-Related Metabolic Syndrome Parameters on Arterial Hypertension

Arterial hypertension is a risk factor for several pathologies, mainly including cardio-cerebrovascular diseases, which rank as leading causes of morbidity and mortality worldwide. Arterial hypertension also constitutes a fundamental component of the metabolic syndrome. Helicobacter pylori infection is one of the most common types of chronic infection globally and displays a plethora of both gastric and extragastric effects. Among other entities, Helicobacter pylori has been implicated in the pathogenesis of the metabolic syndrome. Within this review, we illustrate the current state-of-the-art evidence, which may link several components of the Helicobacter pylori-related metabolic syndrome, including non-alcoholic fatty liver disease and arterial hypertension. In particular, current knowledge of how Helicobacter pylori exerts its virulence through dietary, inflammatory and metabolic pathways will be discussed. Although there is still no causative link between these entities, the emerging evidence from both basic and clinical research supports the proposal that several components of the Helicobacter pylori infection-related metabolic syndrome present an important risk factor in the development of arterial hypertension. The triad of Helicobacter pylori infection, the metabolic syndrome, and hypertension represents a crucial worldwide health problem on a pandemic scale with high morbidity and mortality, like COVID-19, thereby requiring awareness and appropriate management on a global scale.

Association of Inflammatory Markers/Cytokines with Cardiovascular Risk Manifestation in Patients with Endometriosis

This study is aimed at determining the association of inflammatory markers and proinflammatory cytokines with cardiovascular risk manifestation in women with endometriosis as compared to healthy controls. A total of 181 females of reproductive age with the absence of other inflammatory or autoimmune disorders and a lack of hormonal therapy for at least 6 months voluntarily participated in this investigation. Patients were 81 females, laparoscopically diagnosed with endometriosis, while the control group comprised 80 healthy females without any pelvic pathology. All subjects were 20-40 years of age. Exclusion criteria were diabetes, obesity, hypertension, metabolic diseases, cardiovascular, and renal disorders. C-reactive protein, fibrinogen, homocysteine, interleukin-17, and interleukin-33 were analyzed using commercially available ELISA kits. For statistical interpretation, the unpaired Student “t” test was used. All inflammatory markers and cytokines demonstrated elevated levels (P < 0.001) in endometriosis patients as compared to healthy controls. The results of the study revealed that the patients with endometriosis demonstrate a hypercoagulable status due to inflammation, which initiates atherosclerosis and associated complications. Hence, endometriosis can cause a risk of cardiovascular disorders in these patients.

Baseline or 90-day fibrinogen levels and long-term outcomes after ischemic stroke or TIA: Results from the China national stroke registry Ⅲ

BACKGROUND AND AIMS

Elevated fibrinogen levels have been observed in patients with acute ischemic stroke, but the association of fibrinogen with stroke outcomes is still undefined. We aimed to assess the association between baseline or 90-day fibrinogen levels and long-term outcomes in patients with ischemic stroke or transient ischemic attack (TIA).

METHODS

Using data from the China National Stroke Registry Ⅲ, this substudy included 10 518 patients within 7 days (baseline) of onset and 6268 patients at 90 days of recovery. Multivariate Cox regression and logistic regression analyses were used to assess the associations of fibrinogen with poor functional outcome (modified Rankin Scale score 3-6), dependence (modified Rankin Scale score 3-5), all-cause death, and stroke recurrence at 1 year.

RESULTS

Fibrinogen levels at 90 days were higher than those at baseline (443.5 mg/dl versus 393.7 mg/dl; p < 0.001). A high baseline fibrinogen level was associated with poor functional outcome (odds ratio [OR], 1.63; 95% confidence interval [CI], 1.35-1.97) and dependence (OR, 1.68; 95% CI, 1.36-2.09) after adjusting for all confounding risk factors. In contrast, further adjustment for high-sensitivity C-reactive protein attenuated the association between baseline fibrinogen level and all-cause death or stroke recurrence. Furthermore, a high 90-day fibrinogen level was also associated with poor functional outcome (OR, 1.46; 95% CI, 1.07-2.00) and dependence (OR, 1.43; 95% CI, 1.03-1.98) after adjusting for all confounding risk factors.

CONCLUSIONS

High baseline and 90-day fibrinogen levels were associated with outcomes in patients with ischemic stroke or TIA.

Biomarkers in unstable carotid plaque: Physiopathology and Prediction

AIMS

To study the role of cytokines and vascular inflammatory biomarkers in unstable carotid plaque.

BACKGROUND

Clinical studies showed that not only the degree of stenosis but also the type of carotid plaque can be responsible for ipsilateral ischemic stroke.

OBJECTIVE

The objective of this study is to suggest a role for vulnerable carotid atherosclerotic disease in the occurrence of ischemic stroke.

METHODS

PubMed, Embase, Cochrane library, and reference lists have been used to evaluate articles published until February 15, 2021.

RESULTS

Several factors may be involved in unstable plaque. Clinical studies support the involvement of brain inflammatory biomarkers as well as cytokines in the unstable carotid plaque.

CONCLUSIONS

Biomarkers could help to stratify patients with a vulnerable carotid plaque and to personalize the drug treatment. In this review, we briefly discuss the characteristics of vulnerable plaque and the role of biomarkers in the vulnerable carotid plaque.

Predicting value of fibrinogen in identifying cerebrovascular ischemic events in patients with dizziness/vertigo

PURPOSE

Dizziness and vertigo are caused by multiple etiologies, including cerebrovascular ischemic events. However, identifying cerebrovascular ischemic events as a cause of dizziness and vertigo remains a challenge. We tried to assess the value of fibrinogen (FIB) in identifying of cerebral ischemic event in patients with dizziness/vertigo.

METHODS

The study enrolled patients with dizziness/vertigo presented within 72 h in a tertiary hospital. The plasma FIB levels were measured in all participants. According to the final diagnosis, participants were divided into cerebral ischemic events group and non-cerebrovascular diseases group. Multivariate logistic regression was performed to explore the association between FIB and cerebral ischemic events. The receiver operating characteristic curve was performed, and the nomogram was constructed to evaluate the overall prediction ability of FIB in cerebral ischemic event.

RESULTS

A total of 298 participants were enrolled in our study, of 126 cerebral ischemic events patients. Multivariate logistic regression analysis showed that FIB was independently associated with cerebral ischemic event in patients with dizziness (OR = 1.84, 95%CI [1.15, 2.92], p = 0.010). The cut-off value of FIB in predicting cerebral ischemic event was 2.43 g/L (AUC = 0.658). The nomogram showed that higher FIB level was associated with a greater risk of cerebral ischemic event (C-index = 0.800).

CONCLUSIONS

Our study suggested that FIB may be a useful biochemical parameter for identifying cerebral ischemic event in patients with dizziness/vertigo.

A Mendelian randomization of γ' and total fibrinogen levels in relation to venous thromboembolism and ischemic stroke

Fibrinogen is a key component of the coagulation cascade, and variation in its circulating levels may contribute to thrombotic diseases, such as venous thromboembolism (VTE) and ischemic stroke. Gamma prime (γ') fibrinogen is an isoform of fibrinogen that has anticoagulant properties. We applied 2-sample Mendelian randomization (MR) to estimate the causal effect of total circulating fibrinogen and its isoform, γ' fibrinogen, on risk of VTE and ischemic stroke subtypes using summary statistics from genome-wide association studies. Genetic instruments for γ' fibrinogen and total fibrinogen were selected, and the inverse-variance weighted MR approach was used to estimate causal effects in the main analysis, complemented by sensitivity analyses that are more robust to the inclusion of pleiotropic variants, including MR-Egger, weighted median MR, and weighted mode MR. The main inverse-variance weighted MR estimates based on a combination of 16 genetic instruments for γ' fibrinogen and 75 genetic instruments for total fibrinogen indicated a protective effect of higher γ' fibrinogen and higher total fibrinogen on VTE risk. There was also a protective effect of higher γ' fibrinogen levels on cardioembolic and large artery stroke risk. Effect estimates were consistent across sensitivity analyses. Our results provide evidence to support effects of genetically determined γ' fibrinogen on VTE and ischemic stroke risk. Further research is needed to explore mechanisms underlying these effects and their clinical applications.

Inflammation of carotid plaques and risk of cerebrovascular events

Carotid atherosclerotic plaques represent a risk for ischemic stroke. The data indicate that the risk for distal embolization from atherosclerotic lesions in internal carotid arteries is not related only to the degree of stenosis but also to the composition of plaques. The stability of atherosclerotic plaque depends on the thickness of the fibrous cap and plaque hemorrhage. Recent research indicated that the inflammatory activity of atherosclerotic lesions is pivotal in the progression of atherosclerotic plaques. It also promotes the development of unstable atherosclerotic lesions and is related to thromboembolic cerebrovascular complications. Inflammation destabilizes atherosclerotic plaques through the degradation of their fibrotic structure. Inflammation of atherosclerotic plaques was confirmed by histopathologic findings and levels of circulating inflammatory markers which were correlated to the intensity of the inflammation in atherosclerotic lesions. Recently, new techniques like fluorodeoxyglucose positron emission tomography (18-FDG PET) were developed for the identification of inflammation of atherosclerotic lesions in the vessel wall in vivo. Systemic inflammatory markers, particularly interleukins, tumor necrosis factor-alpha and metalloproteinases were shown to be related to the intensity of the inflammatory process in atherosclerotic lesions and the cerebrovascular events. Identification of inflamed atherosclerotic plaques may help to identify unstable atherosclerotic lesions and subjects at high risk for cerebrovascular incidents who need intensive preventive measures including anti-inflammatory medication.

The Mediterranean diet reduces the genetic risk of chromosome 9p21 for myocardial infarction in an Asian population community cohort

The interaction of genetic susceptibility and dietary habits in cardiovascular disease (CVD) remains undetermined. The purpose of this study was to investigate whether a Mediterranean dietary style modified the genetic risk of developing CVD in a Chinese cohort. A total of 2098 subjects with dietary information from a Chinese community cohort (CVDFACTS) were enrolled. Candidate genes, including SNP markers rs1333049 (CDKN2B, 9p21.3), rs17465637 (MIA3, 1q41) and rs501120 (CXCL12, 10q11.21), were genotyped to analyze the association with future CVD. The impact of dietary pattern was also analyzed according to adherence to the diet using the Mediterranean Diet Score (MDS). After an average follow-up of 7.8 years, only the C risk allele of rs1333049 at chromosome 9p21.3 was associated with a higher risk of MI with either an additive [HR = 1.78, 95% CI:1.23-2.5] or a recessive model [HR = 2.40, 95% CI: 1.42-4.04], and the CC genotype had a higher risk of developing MI (p = 0.009, log-rank test). There was no significant difference in the association of the lipid profile with future CV outcomes among the MDS tertiles. However, the high MI risk of the CC genotype in individuals consuming a less healthy diet (MDS1) (HR: 6.39, 95% CI: 1.74-23.43) significantly decreased to 2.38 (95% CI: 0.57-10.04) in individuals consuming a healthier diet (MDS3), indicating that a healthier dietary pattern (higher MDS) modified the risk of developing MI in carriers of variants in CDKN2B. In conclusion, genetic variants of CDKN2B at 9p21 were significantly associated with future MI risk in a Chinese cohort, and the genetic risk of MI could be modified by a healthier diet.

Is Hyperuricemia, an Early-Onset Metabolic Disorder, Causally Associated with Cardiovascular Disease Events in Han Chinese?

BACKGROUND

Serum uric acid (SUA) has gradually been recognized as a potential risk factor for cardiovascular disease (CVD). However, whether the relationship is causal remains controversial.

METHODS

We employed two methods to demonstrate the importance of SUA in CVD development. First, we examined the onset sequence of hyperuricemia in relation to five cardiometabolic (CM) diseases. Second, we conducted a Mendelian randomization (MR) study to causally infer the relationship between SUA and CVD. The information collected from the Cardiovascular Disease Risk Factors Two-Township Study (CVDFACTS) and Taiwan Biobank was used, respectively.

RESULTS

The onset sequence study showed that hyperuricemia and hypo-alpha-lipoproteinemia (low HDL-C) have earlier ages of onset than other CM diseases. For the MR analysis, the high weighted genetic risk score (WGRS) group had a significantly increased cumulative lifetime risk of CVD compared with the low WGRS group (OR = 1.62, (1.17-2.23), P = 0.003). Sensitivity analysis using the WGRS derived from other populations' SUA-influential SNPs revealed similar results.

CONCLUSIONS

We showed that hyperuricemia is an earlier-onset metabolic disorder than hypertension, hypertriglyceridemia, and diabetes mellitus, indicating that high SUA plays an upstream role in CM development. Moreover, our MR study results support the idea that hyperuricemia may play a causal role in CVD development. Further validation studies in more populations are needed.

Mendelian randomization evaluation of causal effects of fibrinogen on incident coronary heart disease

BACKGROUND

Fibrinogen is an essential hemostatic factor and cardiovascular disease risk factor. Early attempts at evaluating the causal effect of fibrinogen on coronary heart disease (CHD) and myocardial infraction (MI) using Mendelian randomization (MR) used single variant approaches, and did not take advantage of recent genome-wide association studies (GWAS) or multi-variant, pleiotropy robust MR methodologies.

METHODS AND FINDINGS

We evaluated evidence for a causal effect of fibrinogen on both CHD and MI using MR. We used both an allele score approach and pleiotropy robust MR models. The allele score was composed of 38 fibrinogen-associated variants from recent GWAS. Initial analyses using the allele score used a meta-analysis of 11 European-ancestry prospective cohorts, free of CHD and MI at baseline, to examine incidence CHD and MI. We also applied 2 sample MR methods with data from a prevalent CHD and MI GWAS. Results are given in terms of the hazard ratio (HR) or odds ratio (OR), depending on the study design, and associated 95% confidence interval (CI). In single variant analyses no causal effect of fibrinogen on CHD or MI was observed. In multi-variant analyses using incidence CHD cases and the allele score approach, the estimated causal effect (HR) of a 1 g/L higher fibrinogen concentration was 1.62 (CI = 1.12, 2.36) when using incident cases and the allele score approach. In 2 sample MR analyses that accounted for pleiotropy, the causal estimate (OR) was reduced to 1.18 (CI = 0.98, 1.42) and 1.09 (CI = 0.89, 1.33) in the 2 most precise (smallest CI) models, out of 4 models evaluated. In the 2 sample MR analyses for MI, there was only very weak evidence of a causal effect in only 1 out of 4 models.

CONCLUSIONS

A small causal effect of fibrinogen on CHD is observed using multi-variant MR approaches which account for pleiotropy, but not single variant MR approaches. Taken together, results indicate that even with large sample sizes and multi-variant approaches MR analyses still cannot exclude the null when estimating the causal effect of fibrinogen on CHD, but that any potential causal effect is likely to be much smaller than observed in epidemiological studies.

Associations between dietary risk factors and ischemic stroke: a comparison of regression methods using data from the Multi-Ethnic Study of Atherosclerosis

OBJECTIVES

We analyzed dietary patterns using reduced rank regression (RRR), and assessed how well the scores extracted by RRR predicted stroke in comparison to the scores produced by partial least squares and principal component regression models.

METHODS

Dietary data at baseline were used to extract dietary patterns using the 3 methods, along with 4 response variables: body mass index, fibrinogen, interleukin-6, and low-density lipoprotein cholesterol. The analyses were based on 5,468 males and females aged 45-84 years who had no clinical cardiovascular disease, using data from the Multi-Ethnic Study of Atherosclerosis.

RESULTS

The primary factor derived by RRR was positively associated with stroke incidence in both models. The first model was adjusted for sex and race and the second model was adjusted for the variables in model 1 as well as smoking, physical activity, family and sibling history of stroke, the use of any lipid-lowering medication, the use of any anti-hypertensive medication, hypertension, and history of myocardial infarction (model 1: hazard ratio [HR], 7.49; 95% confidence interval [CI], 1.66 to 33.69; p for trend=0.01; model 2: HR, 6.83; 95% CI, 1.51 to 30.87 for quintile 5 compared with the reference category; p for trend=0.02).

CONCLUSIONS

Based primarily on RRR, we identified that a dietary pattern high in fats and oils, poultry, non-diet soda, processed meat, tomatoes, legumes, chicken, tuna and egg salad, and fried potatoes and low in dark-yellow and cruciferous vegetables may increase the incidence of ischemic stroke.

Ischemic stroke in patients with POEMS syndrome: a case report and comprehensive analysis of literature

Background

POEMS syndrome is a rare multi-systemic disease characterized by polyneuropathy, organomegaly, endocrinopathy, monoclonal gammopathy, and skin changes. Arterial or venous thrombosis is a less-common complication of POEMS syndrome. Ischemic stroke has also been reported sporadically. However, the association between POEMS syndrome and ischemic stroke has not been entirely understood.

Methods

A case of ischemic stroke caused by cerebral vasculitis in a patient with POEMS syndrome was presented. Then a comprehensive review and analysis of the literature were performed.

Results

A total of 28 patients were identified. The common clinical manifestations of POEMS syndrome were rather non-specific in patients with ischemic stroke compared with those of patients without ischemic stroke. Twenty patients were found with multiple ischemic lesions (71.5%). In the 25 patients who had undergone the evaluation of cerebral arteries, nineteen patients (76.0%) were found with cerebral vasculopathy. Twelve patients (48.0%) had more than one cerebral artery involved. Ischemic events were documented in 8 patients even when they were undergoing all the therapy for ischemic stroke. Ten (55.6%) of the 18 patients who had survival data died within two years after stroke events.

Conclusion

Comprehensive analysis of literature revealed several trends in patients with ischemic stroke and POEMS syndrome including a low survival rate and a preponderance of cerebral vasculopathy and multiple cerebral arteries affected. Ischemic stroke may be a poor outcome predictor in patients with POEMS syndrome. Further researches focusing on a larger cohort may help in better characterizing and treating this rare complication of POEMS syndrome.

Serum fibrinogen and cardiovascular events in Chinese patients with type 2 diabetes and stable coronary artery disease: a prospective observational study

OBJECTIVES

The aim of this study was to investigate the association of serum fibrinogen with cardiovascular events (CVE) in Chinese patients with type 2 diabetes mellitus (T2DM) and stable coronary artery disease (CAD).

DESIGN

An observational study.

SETTING

FuWai Hospital in Beijing, China.

PARTICIPANTS

A cohort of 1466 patients with T2DM and angiographic-proven stable CAD was evaluated.

OUTCOME MEASURES

Baseline serum fibrinogen levels were measured and trisected into 'low', 'middle' and 'high'. Their association with CVE was explored using Cox proportional hazard models.

RESULTS

With 20.2 months (average) follow-up, 44 (3%) were lost to follow-up and 96 patients developed CVE. Compared with the patients without CVE, the ones who developed CVE had higher levels of fibrinogen. Univariable regression revealed a significant relation of fibrinogen to CVE (HR (HR) 1.25, 95% CI 1.06 to 1.47, p=0.010) per SD increase of fibrinogen at baseline. After adjusting for multiple established cardiovascular disease (CVD) risk factors, the association persisted (HR 1.30, 95% CI 1.02 to 1.66, p=0.037). Moreover, after adjusting for CVD risk factors, the HRs for middle-serum and high-serum fibrinogen concentration, using 'low' group as reference, were 1.23 (95% CI 0.69 to 2.20) and 2.20 (95% CI 1.11 to 3.36, p=0.049).

CONCLUSIONS

We first indicated that elevated fibrinogen level was independently associated with increased CVE in Chinese patients with T2DMand stable CAD.

Molecular Links and Biomarkers of Stroke, Vascular Dementia, and Alzheimer's Disease

Stroke is a very common neurological disease, and it occurs when the blood supply to part of the brain is interrupted and the subsequent shortage of oxygen and nutrients causes damage to the brain tissue. Stroke is the second leading cause of death and the third leading cause of disability-adjusted life years. The occurrence of stroke increases with age, but anyone at any age can suffer a stroke. Stroke can be broadly classified in two major clinical types: ischemic stroke (IS) and hemorrhagic stroke. Research also revealed that stroke, vascular dementia (VaD), and Alzheimer's disease (AD) increase with a number of modifiable factors, and most strokes can be prevented and/or controlled through pharmacological or surgical interventions and lifestyle changes. The pathophysiology of stroke, VaD, and AD is complex, and recent molecular and postmortem brain studies have revealed that multiple cellular changes have been implicated, including inflammatory responses, microRNA alterations, and marked changes in brain proteins. These molecular and cellular changes provide new information for developing therapeutic strategies for stroke and related vascular disorders treatment. IS is the major risk factor for VaD and AD. This chapter summarizes the (1) links among stroke-VaD-AD; (2) updates the latest developments of research in identifying protein biomarkers in peripheral and central nervous system tissues; and (3) critically evaluates miRNA profile and function in human blood samples, animal, and postmortem brains.

Fibrinogen consumption is related to intracranial clot burden in acute ischemic stroke: a retrospective hyperdense artery study

Background

Understanding the underlying mechanism of thrombus formation and its components is critical for effective prevention and treatment of ischemic stroke. The generation of thrombotic clots requires conversion of soluble fibrinogen to an insoluble fibrin network. Quantitative features of intracranial clots causing acute ischemic stroke can be studied on non-contrast enhanced CT (NECT). Here, we evaluated on-admission fibrinogen and clot burden in relation to stroke severity, final infarct volume and in-hospital mortality.

Methods

We included 132 consecutive patients with ischemic stroke and presence of hyperdense artery sign admitted within 6 h from symptom onset. Radiological parameters including clot area (corresponding to clot burden) and final infarct volume were manually determined on NECT. National Institute of Health Stroke Scale (NIHSS) was used to quantify disease severity and short-term outcome.

Results

Median patient age was 77, 58 % were women, and 63 % had an occlusion of the proximal middle cerebral artery segment. Thrombolysis was performed in 60 % and thrombectomy in 44 %. We identified several independent associations. Higher fibrinogen levels on admission were associated with smaller clot burden (p = 0.033) and lower NIHSS on admission (p = 0.022). Patients with lower fibrinogen had a higher clot burden (p = 0.028) and greater final infarct volume (p = 0.003). Higher fibrinogen was associated with a lower risk of in-hospital death or NIHSS score >15 if discharged alive (p = 0.028).

Conclusions

Our study suggests that intracranial clot burden in acute ischemic stroke is associated with fibrinogen consumption, and shows a complex relationship with disease severity, infarct size and in-hospital survival.

Electronic supplementary material

The online version of this article (doi:10.1186/s12967-016-1006-6) contains supplementary material, which is available to authorized users.

Peripheral biomarkers of stroke: Focus on circulatory microRNAs

Stroke is the second leading cause of death in the world. Stroke occurs when blood flow stops, and that stoppage results in reduced oxygen supply to neurons in the brain. The occurrence of stroke increases with age, but anyone at any age can suffer from stroke. Recent research has implicated multiple cellular changes in stroke patients, including oxidative stress and mitochondrial dysfunction, inflammatory responses, and changes in mRNA and proteins. Recent research has also revealed that stroke is associated with modifiable and non-modifiable risk factors. Stroke can be controlled by modifiable risk factors, including diet, cardiovascular, hypertension, smoking, diabetes, obesity, metabolic syndrome, depression and traumatic brain injury. Stroke is the major risk factor for vascular dementia (VaD) and Alzheimer's disease (AD). The purpose of this article is to review the latest developments in research efforts directed at identifying 1) latest developments in identifying biomarkers in peripheral and central nervous system tissues, 2) changes in microRNAs (miRNAs) in patients with stroke, 3) miRNA profile and function in animal brain, and 4) protein biomarkers in ischemic stroke. This article also reviews research investigating circulatory miRNAs as peripheral biomarkers of stroke.

Prognostic significance of mechanical biomarkers derived from pulse wave analysis for predicting long-term cardiovascular mortality in two population-based cohorts

BACKGROUND

Numerous mechanical biomarkers derived from pulse wave analysis (PWA) have been proposed to predict cardiovascular outcomes. However, whether these biomarkers carry independent prognostic value and clinical utility beyond traditional cardiovascular risk factors hasn't been systematically evaluated. We aimed to investigate the additive utility of PWA-derived biomarkers in two independent population-based cohorts.

METHODS

PWA on central arterial pressure waveforms obtained from subjects without a prior history of cardiovascular diseases of two studies was conducted based on the wave transmission and reservoir-wave theory: firstly in the Kinmen study (1272 individuals, a median follow-up of 19.8years); and then in the Cardiovascular Disease Risk Factors Two-Township Study (2221 individuals, median follow-up of 10years). The incremental value of the biomarkers was evaluated by net reclassification index (NRI).

RESULTS

In multivariate Cox analyses accounting for age, gender, body mass index, systolic blood pressure, fasting glucose, high-density- and low-density-lipoprotein cholesterol, and smoking, only systolic (SC) and diastolic rate constant (DC) of reservoir pressure could independently and consistently predict cardiovascular mortality in both cohorts and the combined cohort (SC: hazard ratio 1.18 [95% confidence interval 1.08-1.28, p<0.001; DC: 1.18 [1.09-1.28], p<0.001]. Risk prediction estimates in traditional risk prediction models were significantly more accurate when incorporating peak of reservoir pressure (NRI=0.049, p=0.0361), SC (NRI=0.043, p=0.0236) and DC (NRI=0.054, p=0.047).

CONCLUSIONS

Of all PWA-derived biomarkers, SC and DC were consistently identified as valuable parameters for incremental cardiovascular risk prediction in two large prospective cohorts.

Coexistence of High Fibrinogen and Low High-density Lipoprotein Cholesterol Levels Predicts Recurrent Cerebral Venous Thrombosis

BACKGROUND

Cerebral venous thrombosis (CVT) may lead to serious neurological disorders; however, little is known about the risk factors for recurrent CVT. Our aim was to determine the association between elevated fibrinogen and decreased high-density lipoprotein cholesterol (HDL-C) levels with recurrent CVT.

METHODS

This retrospective cohort study included participants if they had a first episode of objectively defined CVT and were admitted to Xuan Wu Hospital, Capital Medical University from August 2005 to September 2009. Demographic and clinical variables were collected, as well as laboratory parameters, including plasma fibrinogen and HDL-C. Patients with CVT were followed for recurrent symptomatic CVT. Follow-up was through the end of September 2010. Potential predictors of recurrence were analyzed using Cox survival analysis.

RESULTS

At the end of the follow-up, 95 patients were eligible for the study. Twelve of 95 patients (12.6%) had recurred CVT. The median time of recurrence was 7 months (range: 1-39 months). Eight of these 12 (66.7%) experienced recurrence within the first 12 months after their initial CVT. The recurrence rate of CVT was 2.76 per 100 patient-years. Multivariate Cox regression analysis demonstrated that the coexistence of high fibrinogen (>4.00 g/L) and low HDL-C (<1.08 mmol/L) levels at baseline was the only independent predictor for recurrent CVT (hazard ratio: 4.69; 95% confidence interval: 1.10-20.11; P < 0.05). Of the twelve patients with recurrent CVT in our study, 7 (58.3%) had high fibrinogen plus low HDL-C levels. All 7 of these patients took warfarin for 3-12 months, and 6 of 7 had recurrent CVT after the discontinuation of anticoagulant treatment.

CONCLUSIONS

Concomitant high fibrinogen and low HDL-C levels may be associated with recurrence of CVT. The effect of potential risk factors related to atherothrombosis on recurrent CVT should be closely monitored.

The Novelty of the 2015 Guidelines of the Taiwan Society of Cardiology and the Taiwan Hypertension Society for the Management of Hypertension

The prevalence rate of hypertension in Asian countries grows faster than in other parts of the world, where stroke exceeds coronary heart disease in causing morbidities and mortalities. The optimal management of hypertension is therefore an especially important task in Asia. In a transparent and rigorous guideline development process, the most updated information available on the management of hypertension was summarized in the 2015 Taiwan Society of Cardiology (TSOC)/Taiwan Hypertension Society (TSH) hypertension guideline. In contradiction with the ESH/ESH joint hypertension guidelines and the 2014 Joint National Committee (JNC) report, this updated guideline suggests some different blood pressure (BP) targets. In brief, the BP target is 150/90 mm Hg for very elderly patients (≥ 80 years), 130/80 mm Hg for patients with diabetes, coronary heart disease, proteinuric chronic kidney disease or those receiving antithrombotics for stroke prevention, and 140/90 mm Hg for all the other hypertension patients with or without the aforementioned comorbidities. To facilitate the adherence to the guideline, the following was proposed: mnemonics for lifestyle modifications: S-ABCDE (Sodium restriction, Alcohol limitation, Body weight reduction, Cigarette smoking cessation, Diet adaptation, and Exercise adoption), treatment algorithm: PROCEED (Previous experience, Risk factors, Organ damage, Contraindications or unfavorable conditions, Expert's or doctor's judgment, Expenses or cost, and Delivery and compliance issue), and medication adjustment algorithm: AT GOALs (Adherence, Timing of administration, Greater doses, Other classes of drugs, Alternative combination or single-pill combination, and Lifestyle modification + Laboratory tests). In particular, the effort of translating the concept of central BP into clinical practice may stand out from all other hypertension guidelines. In summary, our guidelines may deliver useful information and guidance to clinicians in managing hypertensive patients, including the approach to a more accurate diagnosis, treatment and adjustment algorithm, and evidence-based recommendations.

The role of hs-CRP, D-dimer and fibrinogen in differentiating etiological subtypes of ischemic stroke

The aim of this study was to evaluate the diagnostic value of the serum biochemical markers high-sensitivity C-reactive protein (hs-CRP), D-dimer (DD) and fibrinogen (Fg) in differentiating etiological subtypes of ischemic stroke. This study was a retrospective case-only study, consecutively including patients with acute ischemic stroke. All patients were classified into subtypes using the TOAST classification system. A total of 317 patients were evaluated. Hs-CRP and DD levels were significantly different among the subtypes and were the highest in CE, followed by LAA and SAA; no significant difference between the subtypes was found for Fg. Hs-CRP > 6.96 mg/L was classified as the CE subtype, with a sensitivity of 41% and a specificity of 74%; DD > 791.30 ng/mL was classified as CE, with a sensitivity of 58% and a specificity of 78%. The combination of hs-CRP and DD classification as CE yielded a sensitivity of 65% and a specificity of 91%. DD > 791.30 ng/mL was considered an independent predictive factor of CE. Hs-CRP and DD could be useful for identifying the etiological subtypes of acute ischemic stroke, especially for predicting CE. The diagnostic value of DD was higher than that of hs-CRP.

Chronic stress, depressive symptoms, anger, hostility, and risk of stroke and transient ischemic attack in the multi-ethnic study of atherosclerosis

BACKGROUND AND PURPOSE

This study investigated chronic stress, depressive symptoms, anger, and hostility in relation to incident stroke and transient ischemic attacks in middle-aged and older adults.

METHODS

Data were from the Multi-Ethnic Study of Atherosclerosis (MESA), a population-based cohort study of 6749 adults, aged 45 to 84 years and free of clinical cardiovascular disease at baseline, conducted at 6 US sites. Chronic stress, depressive symptoms, trait anger, and hostility were assessed with standard questionnaires. The primary outcome was clinically adjudicated incident stroke or transient ischemic attacks during a median follow-up of 8.5 years.

RESULTS

One hundred ninety-five incident events (147 strokes; 48 transient ischemic attacks) occurred during follow-up. A gradient of increasing risk was observed for depressive symptoms, chronic stress, and hostility (all P for trend ≤0.02) but not for trait anger (P>0.10). Hazard ratios (HRs) and 95% confidence intervals indicated significantly elevated risk for the highest-scoring relative to the lowest-scoring group for depressive symptoms (HR, 1.86; 95% confidence interval, 1.16-2.96), chronic stress (HR, 1.59; 95% confidence interval, 1.11-2.27), and hostility (HR, 2.22; 95% confidence interval, 1.29-3.81) adjusting for age, demographics, and site. HRs were attenuated but remained significant in risk factor-adjusted models. Associations were similar in models limited to stroke and in secondary analyses using time-varying variables.

CONCLUSIONS

Higher levels of stress, hostility, and depressive symptoms are associated with significantly increased risk of incident stroke or transient ischemic attacks in middle-aged and older adults. Associations are not explained by known stroke risk factors.

A novel SNP associated with nighttime pulse pressure in young-onset hypertension patients could be a genetic prognostic factor for cardiovascular events in a general cohort in Taiwan

Background

Pulse pressure (PP) is a risk factor for cardiovascular disease. It has been reported that ambulatory blood pressure (BP) and nighttime BP parameters are heritable traits. However, the genetic association of pulse pressure and its clinical impact remain undetermined.

Method and Results

We conducted a genome-wide association study of PP using ambulatory BP monitoring in young-onset hypertensive patients and found a significant association between nighttime PP and SNP rs897876 (p = 0.009) at chromosome 2p14, which contains the predicted gene FLJ16124. Young-onset hypertension patients carrying TT genotypes at rs897876 had higher nighttime PP than those with CT and CC genotypes (TT, 41.6±7.3 mm Hg; CT, 39.1±6.0 mm Hg; CC, 38.9±6.3 mm Hg; p<0.05,). The T risk allele resulted in a cumulative increase in nighttime PP (β = 1.036 mm Hg, se. = 0.298, p<0.001 per T allele). An independent community-based cohort containing 3325 Taiwanese individuals (mean age, 50.2 years) was studied to investigate the genetic impact of rs897876 polymorphisms in determining future cardiovascular events. After an average 7.79±0.28 years of follow-up, the TT genotype of rs897876 was independently associated with an increased risk (in a recessive model) of coronary artery disease (HR, 2.20; 95% CI, 1.20–4.03; p = 0.01) and total cardiovascular events (HR, 1.99; 95% CI, 1.29–3.06; p = 0.002), suggesting that the TT genotype of rs897876C, which is associated with nighttime pulse pressure in young-onset hypertension patients, could be a genetic prognostic factor of cardiovascular events in the general cohort.

Conclusion

The TT genotype of rs897876C at 2p14 identified in young-onset hypertensive had higher nighttime PP and could be a genetic prognostic factor of cardiovascular events in the general cohort in Taiwan.

An increase in the cerebral infarction area during fatigue is mediated by il-6 through an induction of fibrinogen synthesis

OBJECTIVES

Our study aimed to investigate the impact of fatigue on the severity of stroke and to explore the underlying mechanisms.

METHODS

Fatigued male rats underwent middle cerebral artery occlusion and the infarcted brain area was determined. Then, coagulation parameters were assessed in the fatigued group and a control group. In addition, the level of fibrinogen was determined in rats deprived of sleep for various numbers of days. To study whether interleukin-6 was involved in fibrinogen synthesis during fatigue, we also measured levels of interleukin-6 in rats deprived of sleep for various numbers of days. Furthermore, brain injury by middle cerebral artery occlusion was measured in wild-type mice, interleukin-6-/- mice and wild-type mice treated with bezafibrate.

RESULTS

More severe cerebral infarction was observed in the fatigued rats, resulting in an infarct ratio of 23.4%. The infarct ratio was significantly increased in the fatigued rats compared with that in the control group (8%, p<0.05). The level of fibrinogen was increased significantly in the fatigued rats compared with that in the control group. In addition, a marked reduction in fibrinogen level was observed in the fatigued interleukin-6-/- mice compared to their wild-type counterparts, whereas no difference was observed between fatigued wild-type mice and interleukin-6-/- rats treated with recombinant human interleukin-6. The reduction in brain injury due to middle cerebral artery occlusion during fatigue was observed in interleukin-6-/- mice and wild-type mice treated with bezafibrate.

CONCLUSION

Fatigue could increase stroke severity and was associated with the interleukin-6-induced expression of fibrinogen.

Evaluating the diagnostic value of vWF:Ag, D-D and FDP in patients with acute cerebral infarction using ROC curves

Cerebral infarction is usually associated with arteriosclerosis, vascular endothelial cell injury and blood flow through the vascular system. The diagnostic value of markers, including von Willebrand factor antigen (vWF:Ag), D-dimer (D-D) and fibrinogen/fibrin degradation product (FDP), have not been studied in patients with acute cerebral infarction. Thus, the aim of the present study was to use receiver operating characteristic (ROC) curves to evaluate the diagnostic significance of vWF:Ag, D-D and FDP in 94 cases of acute cerebral infarction. The results revealed that vWF:Ag and D-D concentrations were significantly higher in acute cerebral infarction patients as compared with the normal controls (P<0.01), whereas no statistically significant difference in FDP was observed between the groups (P>0.01). Plasma vWF:Ag and D-D concentrations significantly correlated with the National Institute of Health Stroke Scale (NIHSS) scores (r=0.625 and 0.582, respectively; P<0.01). In addition, the vWF:Ag concentration significantly correlated with the D-D concentration (r=0.320; P<0.01), whereas FDP concentration did not correlate with D-D or vWF:Ag concentrations or the NIHSS scores (r=0.172, 0.188 and 0.065, respectively; P>0.05). The area under the ROC curve using vWF:Ag as a diagnostic marker in patients with acute cerebral infarction was 0.900, while for D-D the area was 0.795 and for FDP the area was 0.465. Logistic regression analysis revealed that the odds ratios of vWF:Ag and D-D were 16.727 and 2.324, respectively, which were statistically significant (P<0.001 and 0.023, respectively). These results indicated that using vWF:Ag as a diagnostic marker is likely to significantly improve the sensitivity of diagnosing patients with acute cerebral infarction. The diagnostic value of vWF:Ag concentration was significantly higher compared with D-D and FDP levels.

Common quantitative trait locus downstream of RETN gene identified by genome-wide association study is associated with risk of type 2 diabetes mellitus in Han Chinese: a Mendelian randomization effect

OBJECTIVE

Plasma resistin level is a potential molecular link between obesity and diabetes. Causal role of resistin, type 2 diabetes mellitus (T2DM) and genetic variants have not been thoroughly investigated. Therefore, we conducted a genome-wide association study (GWAS) to identify quantitative trait loci associated with resistin levels and investigated whether these variants were prospectively associated with the development of metabolic syndrome (MetS) and T2DM in an independent community-based cohort, the CardioVascular Disease risk FACtors Two-township Study (CVDFACTS).

RESEARCH DESIGN AND METHODS

We genotyped 382 young-onset hypertensive (YOH) subjects with Illumina HumanHap550 chips and searched for quantitative trait loci (QTLs) of resistin in the 1(st) stage GWAS and confirmed the finding in another 559 YOH subjects. Logistic regression was used to examine the Mendelian randomization effects between genotypes of confirmed QTLs and metabolic outcomes in 3400 subjects of CVDFACTS.

RESULTS

Two single nucleotide polymorphisms (SNP) (rs3745367 and rs1423096) were significantly associated with resistin levels (p = 5.52 × 10(-15) and p = 2.54 × 10(-20) ) and replicated in another 559 YOH subjects (p = 1.29 × 10(-3) and p = 1.13 × 10(-7) ), respectively. The SNP rs1423096 was further associated with the levels of HDL-C (p = 0.006), the risk of MetS (OR = 2.21, p = 0.0034) and T2DM (OR = 1.62, p = 0.0063) in the CVDFACTS. People with the haplotypes A-G and G-G determined by rs3745367 and rs1423096 showed a significantly increased T2DM risk (p = 0.0068 and p = 0.0035, respectively) compared with those with A-A haplotype.

CONCLUSION

We have found that rs3745367 and rs1423096 on the RETN gene were significantly associated with resistin levels. However, rs1423096, downstream of RETN, seems to be associated with MetS and T2DM risk more so than rs3745367. The established genotype-disease association points to a causal association of resistin and T2DM.

Derivation and validation of diagnostic thresholds for central blood pressure measurements based on long-term cardiovascular risks

OBJECTIVES

This study sought to derive and validate outcome-driven thresholds of central blood pressure (CBP) for diagnosing hypertension.

BACKGROUND

Current guidelines for managing patients with hypertension mainly rely on blood pressure (BP) measured at brachial arteries (cuff BP). However, BP measured at the central aorta (central BP [CBP]) may be a better prognostic factor for predicting future cardiovascular events than cuff BP.

METHODS

In a derivation cohort (1,272 individuals and a median follow-up of 15 years), we determined diagnostic thresholds for CBP by using current guideline-endorsed cutoffs for cuff BP with a bootstrapping (resampling by drawing randomly with replacement) and an approximation method. To evaluate the discriminatory power in predicting cardiovascular outcomes, the derived thresholds were tested in a validation cohort (2,501 individuals with median follow-up of 10 years).

RESULTS

The 2 analyses yielded similar diagnostic thresholds for CBP. After rounding, systolic/diastolic threshold was 110/80 mm Hg for optimal BP and 130/90 mm Hg for hypertension. Compared with optimal BP, the risk of cardiovascular mortality increased significantly in subjects with hypertension (hazard ratio: 3.08, 95% confidence interval: 1.05 to 9.05). Of the multivariate Cox proportional hazards model, incorporation of a dichotomous variable by defining hypertension as CBP ≥ 130/90 mm Hg was associated with the largest contribution to the predictive power.

CONCLUSIONS

CBP of 130/90 mm Hg was determined to be the cutoff limit for normality and was characterized by a greater discriminatory power for long-term events in our validation cohort. This report represents an important step toward the application of the CBP concept in clinical practice.

Association between body mass index and cardiovascular disease mortality in east Asians and south Asians: pooled analysis of prospective data from the Asia Cohort Consortium

OBJECTIVE

To evaluate the association between body mass index and mortality from overall cardiovascular disease and specific subtypes of cardiovascular disease in east and south Asians.

DESIGN

Pooled analyses of 20 prospective cohorts in Asia, including data from 835,082 east Asians and 289,815 south Asians. Cohorts were identified through a systematic search of the literature in early 2008, followed by a survey that was sent to each cohort to assess data availability.

SETTING

General populations in east Asia (China, Taiwan, Singapore, Japan, and Korea) and south Asia (India and Bangladesh).

PARTICIPANTS

1,124,897 men and women (mean age 53.4 years at baseline).

MAIN OUTCOME MEASURES

Risk of death from overall cardiovascular disease, coronary heart disease, stroke, and (in east Asians only) stroke subtypes.

RESULTS

49,184 cardiovascular deaths (40,791 in east Asians and 8393 in south Asians) were identified during a mean follow-up of 9.7 years. East Asians with a body mass index of 25 or above had a raised risk of death from overall cardiovascular disease, compared with the reference range of body mass index (values 22.5-24.9; hazard ratio 1.09 (95% confidence interval 1.03 to 1.15), 1.27 (1.20 to 1.35), 1.59 (1.43 to 1.76), 1.74 (1.47 to 2.06), and 1.97 (1.44 to 2.71) for body mass index ranges 25.0-27.4, 27.5-29.9, 30.0-32.4, 32.5-34.9, and 35.0-50.0, respectively). This association was similar for risk of death from coronary heart disease and ischaemic stroke; for haemorrhagic stroke, the risk of death was higher at body mass index values of 27.5 and above. Elevated risk of death from cardiovascular disease was also observed at lower categories of body mass index (hazard ratio 1.19 (95% confidence interval 1.02 to 1.39) and 2.16 (1.37 to 3.40) for body mass index ranges 15.0-17.4 and <15.0, respectively), compared with the reference range. In south Asians, the association between body mass index and mortality from cardiovascular disease was less pronounced than that in east Asians. South Asians had an increased risk of death observed for coronary heart disease only in individuals with a body mass index greater than 35 (hazard ratio 1.90, 95% confidence interval 1.15 to 3.12).

CONCLUSIONS

Body mass index shows a U shaped association with death from overall cardiovascular disease among east Asians: increased risk of death from cardiovascular disease is observed at lower and higher ranges of body mass index. A high body mass index is a risk factor for mortality from overall cardiovascular disease and for specific diseases, including coronary heart disease, ischaemic stroke, and haemorrhagic stroke in east Asians. Higher body mass index is a weak risk factor for mortality from cardiovascular disease in south Asians.

Current role of biomarkers in carotid disease: a systematic review

BACKGROUND AND PURPOSE

Accumulating evidence suggests that carotid plaque vulnerability can be used as a determinant of ischemic stroke risk stratification and carotid intervention. Novel markers of high-risk carotid plaque in patients are needed.

SUMMARY OF REVIEW

Advances in cellular and molecular pathophysiology, the demand for accurately predicting carotid risk, and choosing the optimal prevention strategy are stimulating great interest in the development of novel surrogate markers. Biomarkers in cardiovascular disease are expected to predict the natural history, clinical outcomes, and the efficacy of disease-modifying interventions. We aimed to review the literature regarding clinical data on novel serum biomarkers related to ischemic cerebrovascular events associated with carotid artery disease. We provide background information on the biomarkers related to all aspects of carotid disease: natural history, carotid intervention strategies for symptomatic and asymptomatic patients, perioperative risk prediction, and their therapeutic implications.

CONCLUSION

At present, heterogeneous data support evidence that biological markers can help existing practices to more accurately assess patients at risk for stroke. Randomized-controlled trials for carotid artery disease and carotid intervention, incorporating biomarkers, are needed.

A genome-wide association study reveals a quantitative trait locus of adiponectin on CDH13 that predicts cardiometabolic outcomes

OBJECTIVE

The plasma adiponectin level, a potential upstream and internal facet of metabolic and cardiovascular diseases, has a reasonably high heritability. Whether other novel genes influence the variation in adiponectin level and the roles of these genetic variants on subsequent clinical outcomes has not been thoroughly investigated. Therefore, we aimed not only to identify genetic variants modulating plasma adiponectin levels but also to investigate whether these variants are associated with adiponectin-related metabolic traits and cardiovascular diseases.

RESEARCH DESIGN AND METHODS

We conducted a genome-wide association study (GWAS) to identify quantitative trait loci (QTL) associated with high molecular weight forms of adiponectin levels by genotyping 382 young-onset hypertensive (YOH) subjects with Illumina HumanHap550 SNP chips. The culpable single nucleotide polymorphism (SNP) variants responsible for lowered adiponectin were then confirmed in another 559 YOH subjects, and the association of these SNP variants with the risk of metabolic syndrome (MS), type 2 diabetes mellitus (T2DM), and ischemic stroke was examined in an independent community-based prospective cohort, the CardioVascular Disease risk FACtors Two-township Study (CVDFACTS, n = 3,350).

RESULTS

The SNP (rs4783244) most significantly associated with adiponectin levels was located in intron 1 of the T-cadherin (CDH13) gene in the first stage (P = 7.57 × 10(-9)). We replicated and confirmed the association between rs4783244 and plasma adiponectin levels in an additional 559 YOH subjects (P = 5.70 × 10(-17)). This SNP was further associated with the risk of MS (odds ratio [OR] = 1.42, P = 0.027), T2DM in men (OR = 3.25, P = 0.026), and ischemic stroke (OR = 2.13, P = 0.002) in the CVDFACTS.

CONCLUSIONS

These findings indicated the role of T-cadherin in modulating adiponectin levels and the involvement of CDH13 or adiponectin in the development of cardiometabolic diseases.

Fibrinogen and cardiovascular disease: genetics and biomarkers

Several prospective epidemiological studies and clinical observations provided evidence regarding fibrinogen and coronary artery disease (CAD). Many of these studies firmly correlate fibrinogen with CAD. However, it is uncertain whether this relation is causal or reflects genetic variability and residual confounding by other risk factors. Several polymorphisms on fibrinogen chain genes affect its levels, however only few of the genetic variants are associated with increased cardiovascular risk. As regards the role of fibrinogen in myocardial infarction (MI) studies indicate that genetic variations have at best a modest impact on the process resulting in MI. Therefore, the screening of fibrinogen genes might not be useful for the assessment of the risk of MI. However, the findings that specific genotypes lead to specific differences in fibrinogen levels, but may not be linked to cardiovascular risk, complicates the hypothesis of causality of fibrinogen in the pathogenesis of cardiovascular disease.

Adiponectin gene polymorphism is selectively associated with the concomitant presence of metabolic syndrome and essential hypertension

Objective

Cardiovascular risk increases with the presence of both metabolic syndrome (MetS) and hypertension (HTN). Although the adiponectin (ADIPOQ) gene has been reported to be involved in MetS, its association with HTN remained undetermined. This study aimed to investigate the association of ADIPOQ gene with the phenotypes of HTN and MetS.

Methods

A total of 962 participants from 302 families from the Taiwan young-onset hypertension genetic study were enrolled. Plasma adiponectin were measured, and association analysis was conducted by using GEE regression-based method. Another study, of 1448 unrelated participants, was conducted to replicate the association between ADIPOQ gene and variable phenotypes of MetS with or without HTN.

Results

Among 962 subjects from family samples, the lowest plasma adiponectin value was observed in MetS with HTN component (9.3±0.47 µg/ml) compared with hypertensives (13.4±0.74 µg /ml) or MetS without HTN (11.9±0.60 µg/ml, P<0.05). The SNP rs1501299 (G276T) in ADIPOQ gene was found associated with the presence of HTN in MetS (odds ratio for GG+GT vs. TT = 2.46; 95% CI: 1.14-5.3, p = 0.02), but not rs2241766 (T45G). No association of ADIPOQ gene with HTN alone or MetS without HTN was observed. The significant association of the SNP rs1501299 (G276T) with the phenotype of presence of HTN in MetS was confirmed (odds ratio for GG+GT vs. TT = 2.15; 95% CI: 1.1–4.3) in the replication study.

Conclusions

ADIPOQ genetic variants were selectively and specifically associated with the concomitant presence of MetS and HTN, suggesting potential genetic linkage between MetS and HTN.

Antithrombin III associated with fibrinogen predicts the risk of cerebral ischemic stroke

BACKGROUND AND PURPOSE

The purpose of this study is to examine the feasibility of developing plasma predictive value biomarkers of cerebral ischemic stroke before imaging evidence is acquired.

METHODS

Blood samples were obtained from 198 patients who attended our neurology department as emergencies - with symptoms of vertigo, numbness, limb weakness, etc. - within 4.5 h of symptom onset, and before imaging evidence was obtained and medical treatment. After the final diagnosis was made by MRI/DWI/MRA or CTA in the following 24-72 h, the above cases were divided into two groups: stroke group and non-stroke group according to the imaging results. The levels of baseline plasma antithrombin III (AT-III), thrombin-antithrombin III (TAT), fibrinogen, D-dimer and high-sensitivity C-reactive protein (hsCRP) in the two groups were assayed.

RESULTS

The level of the baseline AT-III in the stroke group was 118.07±26.22%, which was lower than that of the non-stroke group (283.83±38.39%). The levels of TAT, fibrinogen, hsCRP were 7.24±2.28 μg/L, 5.49±0.98 g/L, and 2.17±1.07 mg/L, respectively, which were higher than those of the non-stroke group (2.53±1.23 μg/L, 3.35±0.50 g/L, 1.82±0.67 mg/L). All the P-values were less than 0.001. The D-dimer level was 322.57±60.34 μg/L, which was slightly higher than that of the non-stroke group (305.76±49.52 μg/L), but the P-value was 0.667. The sensitivities of AT-III, TAT, fibrinogen, D-dimer and hsCRP for predicting ischemic stroke tendency were 97.37%, 96.05%, 3.29%, 7.89%, but the specificity was 93.62%, 82.61%, 100% and 100%, respectively, and all the P-values were less than 0.001. High levels of D-dimer and hsCRP were mainly seen in the few cases with severe large-vessel infarction.

CONCLUSIONS

Clinical manifestations of acute focal neurological deficits were associated with plasma AT-III and fibrinogen. These tests might help the risk assessment of acute cerebral ischemic stroke and/or TIA with infarction tendency in the superacute stage before positive imaging evidence is obtained.

Genetic variants of connexin37 are associated with carotid intima-medial thickness and future onset of ischemic stroke

BACKGROUND

Carotid intima-medial thickness (IMT) is a surrogate marker of subclinical atherosclerosis. This study aimed to investigate the impacts of genetic variants on IMT and future development of ischemic stroke in a cohort, followed by an independent replication study.

METHODS

B-mode carotid ultrasound was performed among 3330 healthy adults in the CVDFACT cohort study, and the genetic effects of atherosclerosis-related genes including connexin37 (GJA4), C-reactive protein (CRP), paraoxonase (PON1), adiponectin (ACDC), angiotensin-converting enzyme (ACE), beta-adrenergic receptor (ADRB1, ADRB2), antithrombin III (SERPINC1), and kinesin family member 6 (KIF6) were evaluated by a multivariate regression model, adjusting for traditional vascular risk factors. Study subjects were prospectively followed for the development of ischemic stroke to assess the prognostic impacts of these genetic variants. An independent case-control study was performed to replicate the genetic association from the cohort study.

RESULTS

The T allele of connexin37 C1019T polymorphism significantly affected IMT (β=0.014, p=0.013) after adjusting for traditional risk factors. During an average follow-up period of 10.7 years, 80 patients with ischemic stroke (2.4%) were identified. The connexin37 1019T allele was significantly associated with an increased rate of ischemic stroke under an additive model, with hazard ratios (HR) of 2.83 (95% confidence interval, 1.2-6.66) and 1.69 (95% confidence interval, 1.06-2.71), comparing TT and CT genotype with CC, respectively. After Cox analysis, age (HR, 1.78 every 10 years), diabetes mellitus (HR, 2.63), hypertension (HR, 2.08), and the T allele of C1019T polymorphism of GJA4 (HR, 1.69) were identified as independent predictors of ischemic stroke. The relationship between T allele of C1019T polymorphism of GJA4 gene and ischemic stroke was also confirmed by an independent association study.

CONCLUSION

Connexin 37 genetic variants significantly affect carotid IMT and contribute to future development of ischemic stroke.