Circulating biomarkers and incident ischemic stroke in the Framingham Offspring Study

Association of Neurotrophic Factors at Midlife With In Vivo Measures of β-Amyloid and Tau Burden 15 Years Later in Dementia-Free Adults

BACKGROUND AND OBJECTIVES

Neurotrophic factors (NTFs) play an important role in Alzheimer disease (AD) pathophysiology. Brain-derived neurotrophic factor (BDNF) and vascular endothelial growth factor (VEGF) are important NTFs. However, a direct link of BDNF and VEGF circulating levels with in vivo measures of amyloid-β (Aβ) and tau burden remains to be elucidated. We explored the relationship of BDNF and VEGF serum levels with future brain Aβ and tau pathology in a cohort of cognitively healthy, predominantly middle-aged adults and tested for possible effect modifications by sex and menopausal status.

METHODS

This cross-sectional analysis was conducted using data from the Framingham Heart Study (FHS), a community-based cohort study. The study sample included cognitively healthy participants from the FHS Offspring and Third-generation cohorts. BDNF and VEGF were measured in the third-generation cohort during examination cycles 2 (2005-2008) and 1 (2002-2005), respectively, and in the offspring cohort during examination cycle 7 (1998-2001). Participants underwent 11C-Pittsburgh compound B amyloid and 18F-Flortaucipir tau-PET imaging (2015-2021). Linear regression models were used to assess the relationship of serum BDNF and VEGF levels with regional tau and global Aβ, adjusting for potential confounders. Interactions with sex and menopausal status were additionally tested.

RESULTS

The sample included 414 individuals (mean age = 41 ± 9 years; 51% female). Continuous measures of BDNF and VEGF were associated with tau signal in the rhinal region after adjustment for potential confounders (β = -0.15 ± 0.06, p = 0.018 and β = -0.19 ± 0.09, p = 0.043, respectively). High BDNF (≥32,450 pg/mL) and VEGF (≥488 pg/mL) levels were significantly related to lower rhinal tau (β = -0.27 ± 0.11, p = 0.016 and β = -0.40 ± 0.14, p = 0.004, respectively) and inferior temporal tau (β = -0.24 ± 0.11, p = 0.028 and β = -0.26 ± 0.13, p = 0.049, respectively). The BDNF-rhinal tau association was observed only among male individuals. Overall, BDNF and VEGF were not associated with global amyloid; however, high VEGF levels were associated with lower amyloid burden in postmenopausal women (β = -1.96 ± 0.70, p = 0.013, per 1 pg/mL).

DISCUSSION

This study demonstrates a robust association between BDNF and VEGF serum levels with in vivo measures of tau almost 2 decades later. These findings add to mounting evidence from preclinical studies suggesting a role of NTFs as valuable blood biomarkers for AD risk prediction.

Perspective from single-cell sequencing: Is inflammation in acute ischemic stroke beneficial or detrimental?

BACKGROUND

Acute ischemic stroke (AIS) is a common cerebrovascular event associated with high incidence, disability, and poor prognosis. Studies have shown that various cell types, including microglia, astrocytes, oligodendrocytes, neurons, and neutrophils, play complex roles in the early stages of AIS and significantly affect its prognosis. Thus, a comprehensive understanding of the mechanisms of action of these cells will be beneficial for improving stroke prognosis. With the rapid development of single-cell sequencing technology, researchers have explored the pathophysiological mechanisms underlying AIS at the single-cell level.

METHOD

We systematically summarize the latest research on single-cell sequencing in AIS.

RESULT

In this review, we summarize the phenotypes and functions of microglia, astrocytes, oligodendrocytes, neurons, neutrophils, monocytes, and lymphocytes, as well as their respective subtypes, at different time points following AIS. In particular, we focused on the crosstalk between microglia and astrocytes, oligodendrocytes, and neurons. Our findings reveal diverse and sometimes opposing roles within the same cell type, with the possibility of interconversion between different subclusters.

CONCLUSION

This review offers a pioneering exploration of the functions of various glial cells and cell subclusters after AIS, shedding light on their regulatory mechanisms that facilitate the transformation of detrimental cell subclusters towards those that are beneficial for improving the prognosis of AIS. This approach has the potential to advance the discovery of new specific targets and the development of drugs, thus representing a significant breakthrough in addressing the challenges in AIS treatment.

Plasma homocysteine levels and risk of congestive heart failure or cardiomyopathy: A Mendelian randomization study

Background

Although observational studies have demonstrated associations between elevated plasma homocysteine levels and the risk of cardiovascular diseases, controversy remains.

Objective

This study investigated the causal association of plasma homocysteine levels with congestive heart failure and cardiomyopathy risk.

Methods

We performed a two-sample Mendelian randomization (MR) study of congestive heart failure (n = 218,792), cardiomyopathy (n = 159,811), and non-ischemic cardiomyopathy (n = 187,152). Genetic summary data on the association of single-nucleotide polymorphisms with homocysteine were extracted from the most extensive genome-wide association study of 44,147 individuals. MR analyses, including the random-effect inverse variance-weighted (IVW) meta-analysis, weighted median, simple median, maximum likelihood, penalized weighted median, MR-PRESSO, and MR-Egger regression, were used to estimate the associations between the selected single-nucleotide polymorphisms and congestive heart failure or cardiomyopathy.

Results

The MR analyses revealed no causal role of higher genetically predicted plasma homocysteine levels with congestive heart failure risk (random-effect IVW, odds ratio [OR] per standard deviation (SD) increase in homocysteine levels = 1.753, 95% confidence interval [CI] = 0.674-4.562, P = 0.250), cardiomyopathy (random-effect IVW, OR per SD increase in homocysteine levels = 0.805, 95% CI = 0.583 to 1.020, P = 0.189), or non-ischemic cardiomyopathy (random-effect IVW, OR per SD increase in homocysteine levels = 1.064, 95% CI = 0.927-1.222, P = 0.379). The results were consistent with other analytical methods and sensitivity analyses.

Conclusion

Genetically predicted homocysteine level was not associated with congestive heart failure or cardiomyopathy risk. It is unlikely that homocysteine-lowering therapy decreases the incidence or improves the outcomes of congestive heart failure and cardiomyopathy.

Association between glaucoma and risk of stroke: A systematic review and meta-analysis

Background/objectives

Recently, several studies explored the association between glaucoma and the risk of stroke, but these results were inconsistent. Therefore, we conducted a meta-analysis to examine this possible association.

Methods

We conducted a systematic literature search of PubMed, Embase, and Web of Science from inception until February 28, 2022. Random-effects meta-analysis was conducted by generic inverse variance method. Sensitivity and subgroup analyses were performed. The review protocol has been registered with PROSPERO (CRD42022312797).

Results

Seven studies (involving 362,267 participants) have been published from 2004 to 2017 and included in the meta-analysis. These studies included four retrospective cohort studies, two cross-sectional studies, and one case-control study. Meta-analysis of these data has shown that glaucoma was associated with an increased risk of stroke (OR = 1.94, 95% CI = 1.45-2.59). Most of the subgroup analyses demonstrated similar results. These findings were stable in sensitivity analyses.

Conclusions

We found that glaucoma was associated with an increased risk of stroke. The result suggests that patients with glaucoma need to be assessed the risk of stroke to reduce the incidence of stroke. To better explore the nature of any association, prospective studies that consider the stroke subtypes, sample size, district, and other confounding factors are needed.

The Vascular System: Anatomical, Physiological, Pathological, and Aging Considerations

The vascular system is one of the earliest recognized anatomical systems. It is composed of 3 parts; arterial, capillary, and venous, each with their own unique anatomy and physiology. Blood flow through this system is compromised in aging, atherosclerosis and peripheral vascular disease, and the practicing anesthesiologist must understand both the physiology and pathophysiology of the vascular tree.

An overview of prognostic value of neurologic and cardiac biomarkers in patients with COVID-19 sequelae

Many studies conducted after the pandemic period revealed that, while COVID-19 primarily injured the lungs, it also affects other organs in the form of cardiovascular complications, metabolic derangements, renal damage, and so on. Although we know that inflammatory cascades, complement activation, and pro-inflammatory cytokines are all involved in vasculitic processes that cause organ damage, we do not know the exact mechanism of complications such as acute respiratory distress syndrome (ARDS), cardiovascular ischemia, deep vein thrombosis, pulmonary thromboembolism, and brain injuries (embolism) that are frequently observed in COVID 19. The currently available biomarkers do not predict the severity of the aforementioned complications. As a result, more specific biomarkers such as serum calcium binding protein (S100B), glial fibrillary acid protein (GFAP), myelin basic protein (MBP), neuron-specific enolase (NSE), hs-TNI, (highly sensitive cardiac troponin) - HBDH, (Hydroxybutyrate Dehydrogenase), CK-MB (creatine kinase myocardial band), ST2 (suppression of tumorigenicity 2) are in need for early detection & improved clinical outcome.

Homocysteine Levels Are Associated With the Rupture of Intracranial Aneurysms

Background

Homocysteine (Hcy) levels may be associated with the development of intracranial aneurysms (IAs). However, whether it increases the risk of rupture of IAs is unknown. This study aimed to determine the association between homocysteine levels and IA rupture.

Methods

We retrospectively reviewed patients with IAs and subarachnoid hemorrhage (SAH) at our hospital between January 2019 and May 2021. Clinical data, including Hcy levels and IA images, were assessed. The association between Hcy level and IA rupture was investigated using multivariate logistic regression analyses in patients with IAs and SAH.

Results

A total of 589 patients were included. 546 patients with IAs, including 331 UIA (Unruptured IA) and 215 RIA (Ruptured IA). The average age was 57.43 ± 10.86 years old, and 67.03% were women. Among them, all 215 RIAs lead to SAH. In addition, we also enrolled 43 non-aneurysmal subarachnoid hemorrhage (Na-SAH) patients. The average age was 54.12 ± 10.55 years old, and 53.48% were female. After adjusting for confounders in the multivariate model, Hcy levels were correlated with the rupture of IA (odds ratio [OR] 1.069; 95% confidence interval [CI] 1.025–1.114, p = 0.002) and a-SAH (OR 1.083; 95% CI 1.002–1.170, p = 0.046).

Conclusion

Hcy levels were associated with IA rupture. These findings provide novel insights into IAs rupture, and future studies are needed to confirm this relationship.

Circulating immune cell landscape in patients who had mild ischaemic stroke

INTRODUCTION

Patients who had a mild ischaemic stroke who present with subtle or resolving symptoms sometimes go undiagnosed, are excluded from treatment and in some cases clinically worsen. Circulating immune cells are potential biomarkers that can assist with diagnosis in ischaemic stroke. Understanding the transcriptomic changes of each cell population caused by ischaemic stroke is critical because they work closely in a complicated relationship. In this study, we investigated peripheral blood mononuclear cells (PBMCs) transcriptomics of patients who had a stroke using a single-cell RNA sequencing to understand peripheral immune response after mild stroke based on the gene expression in an unbiased way.

METHODS

Transcriptomes of PBMCsfrom 10 patients who had an acute ischaemic stroke within 24 hours after stroke onset were compared with 9 race-matched/age-matched/gender-matched controls. Individual PBMCs were prepared with ddSeq^TM (Illumina-BioRad) and sequenced on the Illumina NovaSeq 6000 platform.

RESULTS

Notable population changes were observed in patients who had a stroke, especially in NK cells and CD14+ monocytes. The number of NK cells was increased, which was further confirmed by flow cytometry. Functional analysis implied that the activity of NK cells also is enhanced in patients who had a stroke. CD14+ monocytes were clustered into two groups; dendritic cell-related CD14+ monocytes and NK cell-related CD14+ monocytes. We found CD14+ monocyte subclusters were dramatically reduced in patients who had a stroke.

DISCUSSION

This is the first study demonstrating the increased number of NK cells and new monocyte subclusters of mild ischaemic stroke based on the transcriptomic analysis. Our findings provide the dynamics of circulating immune response that could assist diagnosis and potential therapeutic development of mild ischaemic stroke.

The Potential Impact of Neuroimaging and Translational Research on the Clinical Management of Lacunar Stroke

Lacunar infarcts represent one of the most frequent subtypes of ischemic strokes and may represent the first recognizable manifestation of a progressive disease of the small perforating arteries, capillaries, and venules of the brain, defined as cerebral small vessel disease. The pathophysiological mechanisms leading to a perforating artery occlusion are multiple and still not completely defined, due to spatial resolution issues in neuroimaging, sparsity of pathological studies, and lack of valid experimental models. Recent advances in the endovascular treatment of large vessel occlusion may have diverted attention from the management of patients with small vessel occlusions, often excluded from clinical trials of acute therapy and secondary prevention. However, patients with a lacunar stroke benefit from early diagnosis, reperfusion therapy, and secondary prevention measures. In addition, there are new developments in the knowledge of this entity that suggest potential benefits of thrombolysis in an extended time window in selected patients, as well as novel therapeutic approaches targeting different pathophysiological mechanisms involved in small vessel disease. This review offers a comprehensive update in lacunar stroke pathophysiology and clinical perspective for managing lacunar strokes, in light of the latest insights from imaging and translational studies.

Effect of Patent Foramen Ovale Closure After Stroke on Circulatory Biomarkers

OBJECTIVE

To determine the influence of patent foramen ovale (PFO) closure on circulatory biomarkers.

METHODS

Consecutive patients with PFO-related stroke were prospectively enrolled and followed with serial sampling of cardiac atrial and venous blood pre- and post-PFO closure over time. Candidate biomarkers were identified by mass spectrometry in a discovery cohort first, and lead candidates were validated in an independent cohort.

RESULTS

Patients with PFO-related stroke (n = 254) were recruited and followed up to 4 years (median 2.01; interquartile range 0.77-2.54). Metabolite profiling in the discovery cohort (n = 12) identified homocysteine as the most significantly decreased factor in intracardiac plasma after PFO closure (false discovery rate 0.001). This was confirmed in a validation cohort (n = 181), where intracardiac total homocysteine (tHcy) was immediately reduced in patients with complete closure, but not in those with residual shunting, suggesting association of PFO shunting with tHcy elevation (β 0.115; 95% confidence interval [CI] 0.047-0.183; p = 0.001). tHcy reduction was more dramatic in left atrium than right (p < 0.001), suggesting clearance through pulmonary circulation. Long-term effect of PFO closure was also monitored and compared to medical treatment alone (n = 61). Complete PFO closure resulted in long-term tHcy reduction in peripheral blood, whereas medical therapy alone showed no effect (β -0.208; 95% CI -0.375∼-0.058; p = 0.007). Residual shunting was again independently associated with persistently elevated tHcy (β 0.184; 95% CI 0.051-0.316; p = 0.007).

CONCLUSIONS

PFO shunting may contribute to circulatory tHcy elevation, which is renormalized by PFO closure. PFO is not just a door for clots, but may itself enhance clot formation and injure neurovasculature by clot-independent mechanisms. Biomarkers such as tHcy can potentially serve as cost-effective measures of residual shunting and neurovascular risk for PFO stroke.

Blood markers of endothelial dysfunction and their correlation to cerebrovascular reactivity in patients with chronic hepatitis C infection

Although liver cirrhosis and hepatocellular carcinoma are major consequences of hepatitis C (HCV), there has been an increasing number of studies examining extrahepatic manifestations, especially those caused by systemic chronic inflammation and metabolic complications that might predispose HCV patients to atherosclerosis and ischemic cerebrovascular disease (CVD). The aim of our study was to assess E-selectin, VCAM-1, ICAM-1 and VEGF-A serum levels in patients with chronic HCV infection and to correlate them with cerebrovascular reactivity. A blood sample was taken from eighteen patients with chronic hepatitis C infection and from the same number of healthy blood donors in the control group. The aim was to analyse markers of endothelial dysfunction and to correlate them with cerebrovascular reactivity expressed as breath-holding index (BHI) determined using transcranial color Doppler. The obtained results revealed significant differences between the groups in all endothelial markers except for the E selectin. While the ICAM-1 and sVCAM-1 were significantly increased in the hepatitis group, VEGF-A was significantly decreased. A significant reduction of 0.5 (95% CI 0.2, 0.8) in the mean BHI was found in the hepatitis group (mean BHI 0.64) compared to controls (mean BHI 1.10). No significant association between the BHI and any of the endothelial markers was found in the control group, while in the hepatitis group, the scatter plot of ICAM-1 vs BHI suggested that the association might be present. In conclusion, the results of this study confirm an association between a chronic HCV infection and altered cerebrovascular reactivity as well as higher levels of markers of endothelial activation (ICAM-1, VCAM-1) as possible indicators of an increased CVD risk.

Pro B-type Natriuretic Peptide and Midregional Proadrenomedullin are Associated with Incident Carotid Stenosis During Long Term Follow-up

BACKGROUND

Plasma biomarkers may be useful to detect healthy individuals at increased risk for atherosclerotic manifestations, such as carotid artery stenosis. The aim of this longitudinal cohort study was to evaluate new biomarkers in relation to C-reactive protein and conventional risk factors for carotid artery stenosis during long term follow-up METHODS: The following markers were measured in 5550 middle-aged subjects: C-reactive protein, lipoprotein-associated phospholipase A2, proneurotensin, midregional pro-adrenomedullin, midregional pro-atrial natriuretic peptide, N-terminal pro B-type natriuretic peptide, copeptin, and cystatin C. Subjects with prevalent carotid artery stenosis were excluded. Subjects were followed in national patient registers for 23.4 (interquartile range 19.5-24.3) years regarding incident carotid artery stenosis, both operated and non-operated.

RESULTS

When including conventional risk markers in Cox regression, N-terminal pro B-type natriuretic peptide (Hazard ratio 1.36; 95% confidence interval 1.12-1.65; p = 0.002) was independently associated with incident carotid artery stenosis, whereas there were trends for C-reactive protein (HR 1.20; 95% confidence interval 0.98-1.48; p = 0.071), and midregional pro-adrenomedullin (Hazard ratio 1.21; 95% confidence interval 0.99-1.47; p = 0.061). Midregional pro-adrenomedullin (Hazard ratio 1.30; 95% confidence interval 1.03-1.65; p = 0.029) was independently associated with incident surgery for carotid artery stenosis, whereas there was a trend for N-terminal pro B-type natriuretic peptide (Hazard ratio 1.31; 95% confidence interval 1.00-1.72; p = 0.052).

CONCLUSIONS

N-terminal pro B-type natriuretic peptide and midregional pro-adrenomedullin can be used as predictors for clinically detected carotid artery stenosis during long-term follow-up of healthy subjects.

Association of homocysteine level with risk of stroke: A dose-response meta-analysis of prospective cohort studies

BACKGROUND AND AIMS

Homocysteine (Hcy) level has been increasingly linked with stroke and ischemic stroke (IS). However, a dose-response meta-analysis of prospective cohort studies of the association is lacking. We aimed to explore the quantitative dose-response association of Hcy level with stroke and IS in a meta-analysis of prospective cohort studies.

METHODS AND RESULTS

We performed a systematic search of PubMed, Embase and Web of Science databases up to April 25, 2019 for prospective cohort studies assessing the association of Hcy level with stroke and IS. We used random-effect models to estimate the pooled relative risk (RRs) (with 95% confidence intervals [CIs]) for the association of Hcy with risk of stroke and IS. Restricted cubic splines were used to evaluate possible linear or nonlinear association of Hcy level with stroke and IS. We included 10 prospective cohort studies (7 articles) with 11,061 participants in the meta-analysis. Hcy level was associated with increased risk of stroke (RR = 1.58, 95% CI 1.25-2.00, I² = 39.5%) and IS (RR = 1.54, 95% CI 1.21-1.97, I² = 36.4%) for the highest versus the lowest categories. We found a linear association between Hcy level and stroke (P_nonlinearity = 0.660) and IS (P_nonlinearity = 0.981). For each 1-μmol/L increase in Hcy, the pooled RR was 1.06 (95% CI 1.01-1.12, I² = 59.0%) for stroke and 1.05 (95% CI 1.00-1.11, I² = 58.6%) for IS.

CONCLUSION

This meta-analysis indicated that elevated Hcy level was associated with increased risk of stroke and IS.

Sex Differences in the Association Between Pentraxin 3 and Cognitive Decline: The Cardiovascular Health Study

BACKGROUND

The importance of systemic inflammation, measured by C-reactive protein, in cognitive decline has been demonstrated; however, the role of vascular inflammation is less understood. Pentraxin 3 (PTX3) is a novel marker of vascular inflammation.

METHODS

We followed adults 65 and older, free of cardiovascular disease (CVD) for up to 9 years (n = 1,547) in the Cardiovascular Health Study. We evaluated the relationship between PTX3 and change in cognitive function, measured using the Modified Mini-Mental State Examination (3MSE), and incident cognitive impairment (3MSE < 80). Mediation by CVD events, and effect modification by sex and apolipoprotein E ɛ4 allele (APOE4) were also examined.

RESULTS

The average decline in 3MSE was 0.77 points per year. The association between PTX3 and change in 3MSE differed between women and men (p = .02). In the adjusted model, each standard deviation higher in PTX3 was associated with a 0.20 greater decline in 3MSE score per year in women over follow-up (95% CI: -0. 37, -0.03; p = .02), compared to no change in men (β = 0.07; 95% CI: -0.08, 0.22). CVD events had a minor effect on the associations. No effect modification by APOE4 was found, although we observed the association of PTX3 and cognitive impairment in women was attenuated and nonsignificant after adjustment for APOE4. There was a paradoxical protective association between PTX3 and reduced cognitive impairment in men, even after adjustment for APOE4.

CONCLUSIONS

We found that vascular inflammation was significantly associated with cognitive decline in older women, but not men.

No causal effects of plasma homocysteine levels on the risk of coronary heart disease or acute myocardial infarction: A Mendelian randomization study

BACKGROUND

Although many observational studies have shown an association between plasma homocysteine levels and cardiovascular diseases, controversy remains. In this study, we estimated the role of increased plasma homocysteine levels on the etiology of coronary heart disease and acute myocardial infarction.

METHODS

A two-sample Mendelian randomization study on disease was conducted, i.e. "coronary heart disease" (n = 184,305) and "acute myocardial infarction" (n = 181,875). Nine single nucleotide polymorphisms, which were genome-wide significantly associated with plasma homocysteine levels in 57,644 subjects from the Coronary ARtery DIsease Genome wide Replication and Meta-analysis (CARDIoGRAM) plus The Coronary Artery Disease (C4D) Genetics (CARDIoGRAMplusC4D) consortium genome-wide association study and were known to be associated at p < 5×10-8, were used as an instrumental variable.

RESULTS

None of the nine single nucleotide polymorphisms were associated with coronary heart disease or acute myocardial infarction (p > 0.05 for all). Mendelian randomization analysis revealed no causal effects of plasma homocysteine levels, either on coronary heart disease (inverse variance weighted; odds ratio = 1.015, 95% confidence interval = 0.923-1.106, p = 0.752) or on acute myocardial infarction (inverse variance weighted; odds ratio = 1.037, 95% confidence interval = 0.932-1.142, p = 0.499). The results were consistent in sensitivity analyses using the weighted median and Mendelian randomization-Egger methods, and no directional pleiotropy (p = 0.213 for coronary heart disease and p = 0.343 for acute myocardial infarction) was observed. Sensitivity analyses confirmed that plasma homocysteine levels were not significantly associated with coronary heart disease or acute myocardial infarction.

CONCLUSIONS

The findings from this Mendelian randomization study indicate no causal relationship between plasma homocysteine levels and coronary heart disease or acute myocardial infarction. Conflicting findings from observational studies might have resulted from residual confounding or reverse causation.

Elevated Hs-CRP Levels Are Associated with Higher Risk of Intracranial Arterial Stenosis

Correlation between the level of high-sensitivity C-reactive protein (hs-CRP) and the incidence of intracranial arterial stenosis (ICAS) is unclear. We aim to investigate the relationship between hs-CRP levels and ICAS. A total of 1458 patients aged ≥ 40 years were enrolled in this study. All the participants had a magnetic resonance angiography (MRA) examination for the evaluation of ICAS. Participants were classified into four groups according to stroke and ICAS. Multivariable logistic regression models were used to assess the relationship of hs-CRP levels and ICAS status. A total of 432 (29.63%) subjects had ICAS. The levels of hs-CRP in stroke group were significantly higher than those in non-stroke group (p < 0.001). Patients with ICAS tend to have higher hs-CRP levels (p < 0.001). In multivariate analysis, the fourth hs-CRP quartile had the strongest association with ICAS in both stroke group and non-stroke group (OR 2.512, 95% CI 1.651-3.853, p < 0.001 for stroke group, and OR 2.534, 95% CI 1.435-4.595, p = 0.002 for non-stroke group) among the four quartiles of hs-CRP levels. Our study suggests that elevated serum hs-CRP levels are associated with higher risk of ICAS, in both stroke patients and non-stroke participants.

Circulating Monocyte Chemoattractant Protein-1 and Risk of Stroke: Meta-Analysis of Population-Based Studies Involving 17 180 Individuals

Rationale: Proinflammatory cytokines have been identified as potential targets for lowering vascular risk. Experimental evidence and Mendelian randomization suggest a role of MCP-1 (monocyte chemoattractant protein-1) in atherosclerosis and stroke. However, data from large-scale observational studies are lacking. Objective: To determine whether circulating levels of MCP-1 are associated with risk of incident stroke in the general population. Methods and Results: We used previously unpublished data on 17 180 stroke-free individuals (mean age, 56.7±8.1 years; 48.8% men) from 6 population-based prospective cohort studies and explored associations between baseline circulating MCP-1 levels and risk of any stroke, ischemic stroke, and hemorrhagic stroke during a mean follow-up interval of 16.3 years (280 522 person-years at risk; 1435 incident stroke events). We applied Cox proportional-hazards models and pooled hazard ratios (HRs) using random-effects meta-analyses. After adjustments for age, sex, race, and vascular risk factors, higher MCP-1 levels were associated with increased risk of any stroke (HR per 1-SD increment in ln-transformed MCP-1, 1.07; 95% CI, 1.01-1.14). Focusing on stroke subtypes, we found a significant association between baseline MCP-1 levels and higher risk of ischemic stroke (HR, 1.11 [1.02-1.21]) but not hemorrhagic stroke (HR, 1.02 [0.82-1.29]). The results followed a dose-response pattern with a higher risk of ischemic stroke among individuals in the upper quartiles of MCP-1 levels as compared with the first quartile (HRs, second quartile: 1.19 [1.00-1.42]; third quartile: 1.35 [1.14-1.59]; fourth quartile: 1.38 [1.07-1.77]). There was no indication for heterogeneity across studies, and in a subsample of 4 studies (12 516 individuals), the risk estimates were stable after additional adjustments for circulating levels of IL (interleukin)-6 and high-sensitivity CRP (C-reactive protein). Conclusions: Higher circulating levels of MCP-1 are associated with increased long-term risk of stroke. Our findings along with genetic and experimental evidence suggest that MCP-1 signaling might represent a therapeutic target to lower stroke risk.Visual Overview: An online visual overview is available for this article.

Lipoprotein-Associated Phospholipase A2 Activity and Mass as Independent Risk Factor of Stroke: A Meta-Analysis

Background

The association between lipoprotein-associated phospholipase A2 (Lp-PLA2) and stroke risk is inconsistent. We conducted a meta-analysis to determine whether elevated Lp-PLA2 is a risk factor for stroke.

Methods

Studies were included if they reported Lp-PLA2 mass and/or activity levels and adjusted risk estimates of stroke. The primary outcome was overall stroke incidence. The combined results were shown as relative risks (RRs) with 95% confidence intervals (CI) for per 1 standard deviation (SD) higher value of Lp-PLA2 and the highest versus lowest Lp-PLA2 category.

Results

Twenty-two studies involving 157,693 participants were included for analysis. After adjusting for conventional risk factors, the RRs for overall stroke with 1 SD higher Lp-PLA2 activity and mass were 1.07 (95% CI 1.02-1.13) and 1.11 (95% CI 1.04-1.19), respectively. The RRs of ischemic stroke with 1 SD higher Lp-PLA2 activity and mass were 1.08 (95% CI 1.01-1.15) and 1.11 (95% CI 1.02-1.22), respectively. When comparing the highest and lowest levels of Lp-PLA2, the RRs of stroke for Lp-PLA2 activity and mass were 1.26 (95% CI 1.03-1.54) and 1.56 (95% CI 1.21-2.00), respectively. Finally, when comparing the highest and lowest levels of Lp-PLA2, the pooled RRs of ischemic stroke for Lp-PLA2 activity and mass were 1.29 (95% CI 1.07-1.56) and 1.68 (95% CI 1.12-2.53), respectively.

Conclusions

Elevated baseline Lp-PLA2 levels, detected either by activity or mass, are associated with increased stroke risk.

Low-Grade Inflammation Is Associated with Apathy Indirectly via Deep White Matter Lesions in Community-Dwelling Older Adults: The Sefuri Study

Low-grade inflammation is implicated in the pathogenesis of atherosclerosis, metabolic syndrome, and apathy as a form of vascular depression. We analyzed the brain magnetic resonance imaging findings in 259 community-dwelling older adults (122 men and 137 women, with a mean age of 68.4 years). The serum concentrations of high-sensitivity C-reactive protein (hsCRP) were measured by a quantitative enzyme-linked immunosorbent assay. Logistic regression analysis revealed that the log₁₀ hsCRP value and the presence of a metabolic syndrome were independently associated with confluent but not punctate deep white matter lesions (DWMLs). Path analysis based on structural equation modeling (SEM) indicated that the direct path from the log₁₀ hsCRP to the DWMLs was significant (β = 0.119, p = 0.039). The direct paths from the metabolic syndrome to the log₁₀ hsCRP and to the DWMLs were also significant. The direct path from the DWMLs to apathy (β = −0.165, p = 0.007) was significant, but the direct path from the log₁₀ hsCRP to apathy was not significant. Inflammation (i.e., elevated serum hsCRP levels) was associated with DWMLs independent of common vascular risk factors, while DWMLs were associated with apathy. The present analysis with SEM revealed the more realistic scheme that low-grade inflammation was associated with apathy indirectly via DWMLs in community-dwelling older adults.

Cerebral venous sinus thrombosis due to hyperhomocysteinemia with cystathionine-β-synthase (CBS) gene mutation: A case report

RATIONALE

Risk factors of cerebral venous sinus thrombosis (CVST) are usually divided into acquired risks (e.g., trauma and pregnancy) and genetic risks (inherited thrombophilia). It is essential but not easy to identify the exact one for each patient.

PATIENT CONCERNS

A 14-year-old male patient was admitted in our hospital because of progressively exacerbated severe headache and vomiting for 3 days, accompanied by transient weakness once in his right leg.

DIAGNOSIS

CVST due to hyperhomocysteinemia with cystathionine-β-synthase (CBS) gene mutation.

INTERVENTIONS

Persistent oral anticoagulant therapy.

OUTCOMES

Follow-ups at 4 months and 1 year showed that the patient's symptoms alleviated and did not recur, accompanied with improved MRV image; however, the cranial MRV image did not display as a completely normal one.

LESSONS

We recommend that in case of thrombophilic state, serum homocysteine (Hcy), folic acid, and vitamin B12 levels should be routinely screened; when serum Hcy level is extremely high, congenital diseases caused by gene mutations should be considered. We firstly discovered a new mutation of CBS c.949A>G which had not been reported before.

Abnormal levels of vascular endothelial biomarkers in schizophrenia

Schizophrenia is associated with chronic low-grade inflammation, which has been linked to increased vascular risk and rates of cardiovascular disease. Levels of vascular endothelial growth factor (VEGF), intercellular adhesion molecule-1 (ICAM-1), and vascular cell adhesion molecule-1 (VCAM-1) have been related to aging and neurodegeneration, but their role in schizophrenia remains uncertain. Using a cross-sectional, case-control design, this study included 99 outpatients with schizophrenia and 99 healthy comparison subjects (HCs). Sociodemographic and clinical data were collected, and plasma levels of VEGF, ICAM-1, and VCAM-1 were assayed. A "vascular endothelial index" (VEI) was computed using logistic regression to create a composite measure that maximally differed between groups. General linear models were conducted to examine the possible role of demographic, physical, and lifestyle factors. A linear combination of ICAM-1 and VCAM-1 levels best distinguished the groups, with significantly higher levels of this composite VEI in persons with schizophrenia than HCs. Group differences in the VEI persisted after adjustment for BMI and cigarette smoking. Neither age nor gender was significantly related to the VEI. Schizophrenia patients with higher VEI had earlier age of disease onset, higher systolic and diastolic blood pressure, lower high-density lipoprotein cholesterol, higher insulin resistance, lower levels of mental well-being, and higher Framingham Coronary Heart Disease Risk scores. Schizophrenia is characterized by an elevation of vascular endothelial biomarkers, specifically cell adhesion molecules poised at the intersection between inflammatory response and vascular risk. Interventions aimed at reducing vascular risk may help reduce vascular endothelial abnormalities and prevent cardiovascular morbidity and mortality in schizophrenia.

Abnormal levels of vascular endothelial biomarkers in schizophrenia

Schizophrenia is associated with chronic low-grade inflammation, which has been linked to increased vascular risk and rates of cardiovascular disease. Levels of vascular endothelial growth factor (VEGF), intercellular adhesion molecule-1 (ICAM-1), and vascular cell adhesion molecule-1 (VCAM-1) have been related to aging and neurodegeneration, but their role in schizophrenia remains uncertain. Using a cross-sectional, case-control design, this study included 99 outpatients with schizophrenia and 99 healthy comparison subjects (HCs). Sociodemographic and clinical data were collected, and plasma levels of VEGF, ICAM-1, and VCAM-1 were assayed. A "vascular endothelial index" (VEI) was computed using logistic regression to create a composite measure that maximally differed between groups. General linear models were conducted to examine the possible role of demographic, physical, and lifestyle factors. A linear combination of ICAM-1 and VCAM-1 levels best distinguished the groups, with significantly higher levels of this composite VEI in persons with schizophrenia than HCs. Group differences in the VEI persisted after adjustment for BMI and cigarette smoking. Neither age nor gender was significantly related to the VEI. Schizophrenia patients with higher VEI had earlier age of disease onset, higher systolic and diastolic blood pressure, lower high-density lipoprotein cholesterol, higher insulin resistance, lower levels of mental well-being, and higher Framingham Coronary Heart Disease Risk scores. Schizophrenia is characterized by an elevation of vascular endothelial biomarkers, specifically cell adhesion molecules poised at the intersection between inflammatory response and vascular risk. Interventions aimed at reducing vascular risk may help reduce vascular endothelial abnormalities and prevent cardiovascular morbidity and mortality in schizophrenia.

Increased vascular endothelial growth factor D is associated with atrial fibrillation and ischaemic stroke

OBJECTIVE

Vascular endothelial growth factor D (VEGF-D) has important functions in lymphangiogenesis and angiogenesis. High plasma levels of VEGF-D have been associated with incidence of heart failure. The association of VEGF-D with atrial fibrillation (AF) and stroke is unclear and we hypothesised that VEGF-D could also be associated with incidence of AF and ischaemic stroke.

METHODS

VEGF-D was measured in fasting blood samples of 4689 subjects (40% men) without a history of AF from the Malmö Diet and Cancer Study, a prospective, population-based study in Sweden. Median age was 58 years (range 46-68). Cox regression analyses, adjusted for multiple risk factors, was used to assess AF and ischaemic stroke risk in relation to VEGF-D levels.

RESULTS

During a median follow-up time of 20.6 years, there were 637 cases of incident AF and 322 cases of first ischaemic stroke. After adjustment, VEGF-D was significantly associated with AF (HR 1.13(95% CI 1.04 to 1.23) per 1 SD increase) and ischaemic stroke (HR 1.14(95% CI 1.02 to 1.28) per 1 SD). The association with ischaemic stroke was explained by an increased incidence of AF-related stroke. HRs per 1 SD were 1.34 (95% CI 1.04 to 1.71) for AF-related ischaemic stroke and 1.04 (95% CI 0.90 to 1.19) for ischaemic stroke without AF.

CONCLUSIONS

Increased VEGF-D concentrations were associated with AF and ischaemic stroke. The relationship with ischaemic stroke was more pronounced in subjects with a diagnosis of AF.

Homocysteine and homocysteine-related compounds: an overview of the roles in the pathology of the cardiovascular and nervous systems

Homocysteine, an amino acid containing a sulfhydryl group, is an intermediate product during metabolism of the amino acids methionine and cysteine. Hyperhomocysteinemia is used as a predictive risk factor for cardiovascular disorders, the stroke progression, screening for inborn errors of methionine metabolism, and as a supplementary test for vitamin B₁₂ deficiency. Two organic systems in which homocysteine has the most harmful effects are the cardiovascular and nervous system. The adverse effects of homocysteine are achieved by the action of several different mechanisms, such as overactivation of N-methyl-d-aspartate receptors, activation of Toll-like receptor 4, disturbance in Ca²⁺ handling, increased activity of nicotinamide adenine dinucleotide phosphate-oxidase and subsequent increase of production of reactive oxygen species, increased activity of nitric oxide synthase and nitric oxide synthase uncoupling and consequent impairment in nitric oxide and reactive oxygen species synthesis. Increased production of reactive species during hyperhomocysteinemia is related with increased expression of several proinflammatory cytokines, including IL-1β, IL-6, TNF-α, MCP-1, and intracellular adhesion molecule-1. All these mechanisms contribute to the emergence of diseases like atherosclerosis and related complications such as myocardial infarction, stroke, aortic aneurysm, as well as Alzheimer disease and epilepsy. This review provides evidence that supports the causal role for hyperhomocysteinemia in the development of cardiovascular disease and nervous system disorders.

Association between FSP, CVHI, inflammatory cytokines and the incidence of primary stroke

This case-control study was designed to establish a new risk-prediction model for primary stroke using Framingham stroke profile (FSP), cerebral vascular hemodynamic indexes (CVHI) and plasma inflammatory cytokines including hs-CRP, IL-6, TNF-α and Lp-PLA2. A total of 101 primary stroke patients admitted to Dongguan Houjie Hospital between August 2014 and June 2015 were assigned into the case group, and 156 age- and gender-matched healthy subjects from the Houjie Community were allocated into the control group. The prognostic values of FSP, CVHI and inflammatory cytokines including high sensitive C-reactive protein (hs-CRP), interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α) and lipoprotein-associated phospholipase A2 (Lp-PLA2) were assessed by multivariate logistic regression analysis. Seven risk-prediction models (FSP, CVHI, inflammatory cytokine, FSP+CVHI, FSP+inflammatory cytokine, CVHI+inflammatory cytokine, CVHI+FSP+inflammatory cytokine) were successfully established and the prognostic values were statistically compared by ROC curve and Z test. For FSP, the stroke risk was significantly elevated by 2.85 times when the FSP score was increased by 1 level (P=0.043), increased by 3.25 times for CVHI (P=0.036), 6.53 times for IL-6 (P=0.003), and 7.75 times for Lp-PLA2 (P=0.000). The sensitivity of FSP+CVHI+inflammatory cytokine and CVHI+inflammatory cytokine models was higher than 90%. For model specificity, the specificity of FSP+CVHI+inflammatory cytokine model alone exceeded 90%. FSP, CVHI, IL-6 and Lp-PLA2 are independent risk factors of stroke. Integrating IL-6 and Lp-PLA2 into the models can significantly enhance the risk prediction accuracy of primary stroke. Combined application of FSP+CVHI+inflammatory cytokine is of potential for risk prediction of primary stroke.

Homocysteine in non-valvular atrial fibrillation: Role and clinical implications

Atrial fibrillation (AF), the most common sustained arrhythmia, is associated with a series of adverse complications that cause so-called AF socioeconomic burden. Apart from the classical risk factors, it seems to be novel factors that increase the risk of AF and AF-related stroke. Recently, more and more evidence has well documented the close relationships between homocysteine (Hcy) and AF. As a well-known marker for pro-oxidation and pro-inflammation, Hcy plays an important role in a number of vascular diseases having strong association with AF. This review will discuss the expression of Hcy and its association with ischemic stroke in AF patients especially for elderly patients, and the role and clinical implications of Hcy in the thromboembolic events and rhythm outcome in AF patients. The possible mechanisms linking elevated Hcy and cardiovascular events in AF patients will also be addressed, including oxidative stress, inflammatory response, atrial remodeling, etc.

Joint effect of maternal plasma homocysteine and prepregnancy obesity on child blood pressure: a prospective birth cohort study

BACKGROUND/OBJECTIVES

Elevated homocysteine (Hcy) is a known cardiovascular risk factor. However, its role in intergenerational cardiometabolic risk is unknown. We hypothesized that maternal elevated Hcy can act alone or in combination with maternal prepregnancy obesity to increase child systolic blood pressure (SBP).

METHODS

This study included 1279 mother-child pairs who were enrolled at birth and followed prospectively up to age 9 years from 2003 to 2014 at the Boston Medical Center. Child SBP percentile was calculated according to US reference data and elevated SBP was defined as SBP⩾75th percentile.

RESULTS

A U-shaped relationship between maternal Hcy and her child SBP was observed. The risk for child elevated SBP was higher among those in the lowest quartile (Q1, odds ratio (OR): 1.27; 95% confidence interval (CI): 0.94-1.72), and highest quartile (Q4, OR: 1.34; 95% CI: 1.00-1.81) as compared with those in quartiles 2 and 3. The highest risk of child elevated SBP was found among children born to obese mothers with Hcy in Q4 (OR: 2.22; 95%CI: 1.35-3.64), compared with children of non-obese mothers with Hcy in Q2-Q3. This association was independent from maternal folate and vitamin B12 status, and was not mediated by gestational age or size at birth.

CONCLUSIONS

In this prospective birth cohort, we observed a U-shaped association between maternal Hcy levels and child elevated SBP. Maternal high Hcy (Q4) and prepregnancy obesity jointly increased the risk of child elevated SBP by more than two-fold.

Association of Neovascular Glaucoma with Risk of Stroke: A Population-Based Cohort Study

Neovascular glaucoma (NVG), caused by ocular ischemia, is a serious ocular disease complicated by intractably increased intraocular pressure. Cerebrovascular accidents are classified into ischemic and hemorrhagic stroke. Based on the similar pathogenic mechanisms of NVG and ischemic stroke, we investigated the relationship between NVG and stroke by using a nationally representative sample. This study included 416 NVG patients and 4160 controls. Medical comorbidities were also evaluated. The cumulative incidence of ischemic stroke was 15.6% higher in the NVG cohort than in the control cohort (p < 0.001); the incidence density rates of stroke were 3.80 and 1.19 per 10,000 person-years in the NVG and control cohorts, respectively. According to the multivariable Cox regression results, the estimated adjusted hazard ratio (aHR) of stroke was 2.07 (95% confidence interval (CI) = 1.41–3.02) for the NVG cohort. Furthermore, the NVG cohort was 2.24-fold more likely to develop ischemic stroke (95% CI = 1.51–3.32). The risk of ischemic stroke was higher in patients with hypertension (aHR = 2.09, 95% CI = 1.55–2.82) and in patients with diabetic retinopathy (aHR = 1.69, 95% CI = 1.05–2.72). Notably, patients with NVG have a higher risk of ischemic stroke, but not hemorrhagic stroke.

C-reactive protein gene polymorphism predicts the risk of thromboembolic stroke in patients with atrial fibrillation: a more than 10-year prospective follow-up study

Essentials We studied the C-reactive protein (CRP) gene on stroke risk in atrial fibrillation (AF) patients. 725 patients with CRP triallelic polymorphism genotype were followed-up for more than 10 years. Patients with the A-390/T-390 allele of the CRP gene were more likely to get ischemic stroke. The triallelic polymorphism of the CRP is related to ischemic stroke in AF patients.

SUMMARY

Background Little evidence is available regarding the impact of genetic polymorphisms on the risk of thromboembolic stroke in patients with atrial fibrillation (AF). An increasing body of evidence is demonstrating that inflammatory responses play an important role in the pathophysiology of AF. Objectives To investigate the effect of genetic polymorphisms of the C-reactive protein (CRP) gene on the incidence of thromboembolic stroke in patients with AF. Methods A total of 725 AF patients were longitudinally followed up for > 10 years; this is the largest and longest AF follow-up cohort with genetic data. CRP promoter triallelic polymorphisms (C-390A and C-390T) were genotyped, and CRP levels were divided into four quartiles. Results Patients with higher CRP levels were more likely to develop thromboembolic stroke than those with lower CRP levels (P<0.001, log-rank test for comparison of four quartiles). After adjustment for conventional risk factors, patients with higher CRP levels were more likely to develop thromboembolic stroke than those in the lowest CRP quartile (hazard ratio [HR] 2.27, 95% confidence interval [CI] 1.08-4.81; the lowest CRP quartile was the reference group). Patients carrying the A-390 or T-390 allele had higher CRP levels (3.35 ± 2.71 mg L-1 versus 2.43 ± 2.00 mg L-1 ), and were more likely to develop thromboembolic stroke, even after adjustment for conventional risk factors (HR 2.07, 95% CI 1.23-3.48). Conclusion The CRP triallelic polymorphism and the CRP level are associated with the risk of incident thromboembolic stroke in patients with AF.

Assessed and Emerging Biomarkers in Stroke and Training-Mediated Stroke Recovery: State of the Art

Since the increasing update of the biomolecular scientific literature, biomarkers in stroke have reached an outstanding and remarkable revision in the very recent years. Besides the diagnostic and prognostic role of some inflammatory markers, many further molecules and biological factors have been added to the list, including tissue derived cytokines, growth factor-like molecules, hormones, and microRNAs. The literatures on brain derived growth factor and other neuroimmune mediators, bone-skeletal muscle biomarkers, cellular and immunity biomarkers, and the role of microRNAs in stroke recovery were reviewed. To date, biomarkers represent a possible challenge in the diagnostic and prognostic evaluation of stroke onset, pathogenesis, and recovery. Many molecules are still under investigation and may become promising and encouraging biomarkers. Experimental and clinical research should increase this list and promote new discoveries in this field, to improve stroke diagnosis and treatment.

"Cerebral Small Vessel Disease in subclinical and clinical stages, role of inflammation for risk prediction and potential treatment targets, and management strategies"

Stroke and dementia are the most common neurological disorders worldwide. Cerebrovascular disease, particularly cerebral small vessel disease (CSVD) is implicated in both, and the two main types of CSVD (hypertensive vasculopathy and cerebral amyloid angiopathy) account for the majority of cerebrovascular contributions to stroke and dementia. Current knowledge of CSVD may influence treatment decisions and preventive efforts. Although the causes of CSVD are not entirely elucidated, ongoing research of the pathophysiology of CSVD, such as the role of inflammation, is helping identify potential treatment targets, evaluate prediction models and develop preventive strategies. Given the detectability of CSVD in preclinical stages using brain MRI, a long window of opportunity is presented to implement existent preventive measures. This review considers CSVD including its subclinical manifestations detected using brain MRI, clinical manifestations, use of markers of CSVD as predictors of clinical outcomes such as dementia and stroke, and presents potential management strategies when seeing patients with cerebral small vessel disease to reduce its disease burden and clinical consequences. Clinical trials have evaluated some aspects of CSVD treatment and are beginning to recognize CSVD as endpoint in subclinical stages. Future studies will clarify if this approach is able to delay onset of dementia and prevent stroke occurrence, meanwhile implementation of existent recommendations for the prevention and treatment of stroke and dementia may reduce disability and clinical outcomes related to CSVD.