HDL cholesterol and stroke risk: The Multi-Ethnic Study of Atherosclerosis

The serum metabolomic profiles of atrial fibrillation patients treated with direct oral anticoagulants or vitamin K antagonists

AIMS

Long-term oral anticoagulation is the primary therapy for preventing ischemic stroke in patients with atrial fibrillation (AF). Different types of oral anticoagulant drugs can have specific effects on the metabolism of patients. Here we characterize, for the first time, the serum metabolomic and lipoproteomic profiles of AF patients treated with anticoagulants: vitamin K antagonists (VKAs) or direct oral anticoagulants (DOACs).

MATERIALS AND METHODS

Serum samples of 167 AF patients (median age 78 years, 62 % males, 70 % on DOACs treatment) were analyzed via high resolution 1H nuclear magnetic resonance (NMR) spectroscopy. Data on 25 metabolites and 112 lipoprotein-related fractions were quantified and analyzed with multivariate and univariate statistical approaches.

KEY FINDINGS

Our data provide evidence that patients treated with VKAs and DOACs present significant differences in their profiles: lower levels of alanine and lactate (odds ratio: 1.72 and 1.84), free cholesterol VLDL-4 subfraction (OR: 1.75), triglycerides LDL-1 subfraction (OR: 1.80) and 4 IDL cholesterol fractions (ORs ∼ 1.80), as well as higher levels of HDL cholesterol (OR: 0.48), apolipoprotein A1 (OR: 0.42) and 7 HDL cholesterol fractions/subfractions (ORs: 0.40-0.51) are characteristic of serum profile of patients on DOACs' therapy.

SIGNIFICANCE

Our results support the usefulness of NMR-based metabolomics for the description of the effects of oral anticoagulants on AF patient circulating metabolites and lipoproteins. The higher serum levels of HDL cholesterol observed in patients on DOACs could contribute to explaining their reduced cardiovascular risk, suggesting the need of further studies in this direction to fully understand possible clinical implications.

Exercise: Just What the Doctor Ordered, But Why? Elucidating Mechanisms for Women's Increased High-Density Lipoprotein Benefit From Exercise and for the Health ABC Study

High-density lipoprotein (HDL) is protective against cardiovascular disease. Exercise can increase HDL concentration, and some evidence suggests that this effect occurs more strongly in women than in men. Both HDL and exercise are associated with inflammation. We hypothesized a sex-by-exercise interaction on HDL level, whereby women would benefit from exercise more strongly than men, and tumor necrosis factor alpha and serum soluble tumor necrosis factor receptor-2 would mediate this relationship. This study included 2,957 older adult participants (1,520 women; 41% Black, 59% White; 73.6-years-old) from the Health, Aging, and Body Composition study. Regression models revealed a positive exercise-HDL relationship in women only (sex-by-exercise interaction: β = 0.09, p = .013; exercise on HDL in women: β = 0.07, p = .015), mediated by TNFα (axb = 0.15; CI: 0.01, 0.30), suggesting that exercise may increase HDL levels in women through reduced inflammation. Given that vascular risk contributes to Alzheimer's disease risk, findings have implications for sex differences in AD risk factors.

Association between HDL levels and stroke outcomes in the Arab population

Low HDL levels are associated with an increased stroke incidence and worsened long-term outcomes. The aim of this study was to assess the relationship between HDL levels and long-term stroke outcomes in the Arab population. Patients admitted to the Qatar Stroke Database between 2014 and 2022 were included in the study and stratified into sex-specific HDL quartiles. Long-term outcomes included 90-Day modified Rankin Score (mRS), stroke recurrence, and post-stroke cardiovascular complications within 1 year of discharge. Multivariate binary logistic regression analyses were performed to identify the independent effect of HDL levels on short- and long-term outcomes. On multivariate binary logistic regression analyses, 1-year stroke recurrence was 2.24 times higher (p = 0.034) and MACE was 1.99 times higher (p = 0.009) in the low-HDL compared to the high-HDL group. Mortality at 1 year was 2.27-fold in the low-normal HDL group compared to the reference group (p = 0.049). Lower sex-specific HDL levels were independently associated with higher adjusted odds of 1-year post-stroke mortality, stroke recurrence, and MACE (p < 0.05). In patients who suffer a stroke, low HDL levels are associated with a higher risk of subsequent vascular complication.

Novel Size-Based High-Density Lipoprotein Subspecies and Incident Vascular Events

Background High-density lipoprotein (HDL) particle concentration likely outperforms HDL cholesterol in predicting atherosclerotic cardiovascular events. Whether size-based HDL subspecies explain the atheroprotective associations of HDL particle concentration remains unknown. Our objective was to assess whether levels of specific size-based HDL subspecies associate with atherosclerotic cardiovascular disease in a multiethnic pooled cohort and improve risk prediction beyond traditional atherosclerotic cardiovascular disease risk factors. Methods and Results Seven HDL size-based subspecies were quantified by nuclear magnetic resonance (LP4 algorithm; H1=smallest; H7=largest) among participants without prior atherosclerotic cardiovascular disease in ARIC (Atherosclerosis Risk in Communities), MESA (Multi-Ethnic Study of Atherosclerosis), PREVEND (Prevention of Renal and Vascular Endstage Disease), and DHS (Dallas Heart Study) cohorts (n=15 371 people). Multivariable Cox proportional hazards models were used to evaluate the association between HDL subspecies and incident myocardial infarction (MI) or ischemic stroke at follow-up (average 8-10 years) adjusting for HDL cholesterol and risk factors. Improvement in risk prediction was assessed via discrimination and reclassification analysis. Within the pooled cohort (median age 57 years; female 54%; Black 22%) higher H1 (small) and H4 (medium) concentrations were inversely associated with incident MI (hazard ratio [HR]/SD, H1 0.88 [95% CI, 0.81-0.94]; H4 0.89 [95% CI, 0.82-0.97]). H4 but not H1 improved risk prediction indices for incident MI. Increasing H2 and H4 were inversely associated with improved risk prediction indices for composite end point of stroke, MI, and cardiovascular death (HR/SD, H2 0.94 [95% CI, 0.88-0.99]; H4 0.91 [95% CI, 0.85-0.98]). Levels of the large subspecies (H6 and H7) were not associated with any vascular end point. Conclusions Two of 7 HDL size-based subspecies modestly improved risk prediction for MI and composite vascular end points in a large multiethnic pooled cohort. These findings support assessment of precise HDL subspecies for future studies regarding clinical utility.

Developing and Validating a New Model to Predict the Risk of Poor Neurological Status of Acute Ischemic Stroke After Intravenous Thrombolysis

OBJECTIVES

The objective of this study was to develop and validate a predictive model for the risk of poor neurological status in in-hospital patients with acute ischemic stroke (AIS) after intravenous thrombolysis.

METHODS

This 2-center retrospective study included patients with AIS treated at the Advanced Stroke Center of the Second Hospital of Hebei Medical University and Baoding No.1 Central Hospital between January 2018 and January 2020). The neurological function status at day 7 of AIS onset was used as the endpoint of the study, which was evaluated using the National Institute of Health Stroke Scale (NIHSS) score.

RESULTS

A total of 878 patients were included in the study and divided into training (n=652) and validation (n=226) sets. Seven variables were selected as predictors to establish the risk model: age, NIHSS before thrombolysis (NIHSS1), NIHSS 24 hours after thrombolysis (NIHSS3), high-density lipoprotein, antiplatelet, cerebral computed tomography after thrombolysis (CT2), and lower extremity venous color Doppler ultrasound. The risk prediction model achieved good discrimination (the areas under the Receiver Operating Characteristic curve in the training and validation sets were 0.9626 and 0.9413, respectively) and calibration (in the training set Emax=0.072, Eavg=0.01, P =0.528, and in the validation set Emax=0.123, Eavg=0.019, P =0.594, respectively). The decision curve analysis showed that the model could achieve a good net benefit.

CONCLUSIONS

The prediction model obtained in this study showed good discrimination, calibration, and clinical efficacy. This new nomogram can provide a reference for predicting the risk of poor neurological status in patients with acute ischemic stroke after intravenous thrombolysis.

Association of Circulating Circular RNAs (hg38_circ_0008980, and CircDLGAP4) in Diagnosis, Diseases Severity, and Prognosis of Ischemic Stroke

Background

Fast diagnosing ischemic stroke (IS) is a critical issue in clinical studies, as it allows more effective therapy and stops the progression of IS. The blood level of circular RNAs (CircRNAs) after stroke may be a rapid diagnostic marker.

Methods

In this study, the blood level of circRNAs was evaluated using a real-time polymerase chain reaction (PCR). We used logistic and linear regression analysis to assess the potential of circRNAs levels with the risk of IS.

Results

circRNA DLG associated protein 4 (CircDLGAP4) was decreased in patients compared with controls, and logistic regression showed its expression negatively associated with IS risk. The expression level of human genome version 38_Circular_0008980 (hg38_circ_0008980) was reduced significantly in patients with small vessel disease (SVD), and the linear regression analysis showed a negative relationship between hg38_circ_0008980 expressions with SVD subtype. hg38_circ_0008980 expression relative to controls showed a significant association with IS risk.

Conclusion

Taken together, we found a significant decrease in the level of hg38_circ_0008980 after IS; it may act as a novel circRNA in IS pathophysiology with a positive correlation with stroke severity.

Protective Effects of Different Classes, Intensity, Cumulative Dose-Dependent of Statins Against Primary Ischemic Stroke in Patients with Type 2 Diabetes Mellitus

PURPOSE OF REVIEW

The aim of this study is to investigate the protective effects of different statin classes, intensity, and cumulative dose-dependent against primary ischemic stroke in patients with T2DM.

RECENT FINDINGS

The Cox hazards model was used to evaluate statin use on primary ischemic stroke. Case group: T2DM patients who received statins; control group: T2DM patients who received no statins during the follow-up. Adjusted hazard ratio (aHR) for primary ischemic stroke was 0.45 (95% CI: 0.44 to 0.46). Cox regression analysis showed significant reductions in primary ischemic stroke incidence in users of different statin classes. Corresponding aHRs (95% CI) were 0.09 to 0.79 for pitavastatin, rosuvastatin, atorvastatin, pravastatin, simvastatin, fluvastatin, and lovastatin. Multivariate analyses indicated significant reductions in primary ischemic stroke incidence for patients who received different cumulative defined daily doses (cDDDs) per year (cDDD-year). Corresponding aHRs (95% CI) were 0.17 to 0.77 for quartiles 4 to 1 of cDDD-years, respectively (P for trend < .0001). Optimal intensity daily dose of statin use was 0.89 DDD with the lowest aHR of primary ischemic stroke compared with other DDDs. Persistent statin use reduces the risk of primary ischemic stroke in T2DM patients. Higher cDDD-year values are associated with higher reductions in primary ischemic stroke risk in T2DM patients.

Association of Genetic and Allelic Variants of Von Willebrand Factor (VWF), Glutathione S-Transferase and Tumor Necrosis Factor Alpha with Ischemic Stroke Susceptibility and Progression in the Saudi Population

Stroke is a key cerebrovascular disease and important cause of death and disability worldwide, including in the kingdom of Saudi Arabia (KSA). It has a large economic burden and serious socioeconomic impacts on patients, their families and the community. The incidence of ischemic stroke is probably increased by the interaction of GSTT1 and GSTM1 null genotypes with high blood pressure, diabetes and cigarette smoking. The roles of VWF, GSTs and TNF-alpha gene variations in the induction of stroke are still uncertain and require further examination. In the current study, we studied the associations of SNPs in the genes VWF, GSTs and TNF-alpha with stroke in the Saudi population. Genotyping was performed using the ARMS -PCR for TNF-alpha, AS-PCR for VWF and multiplex PCR for GSTs. The study included 210 study subjects: 100 stroke cases and 110 healthy controls. We obtained significant distributions of VWF rs61748511 T > C, TNF-alpha rs1800629 G > A and GST rs4025935 and rs71748309 genotypes between stroke cases and the healthy controls (p < 0.05). The results also indicated that the TNF-alpha A allele was associated with risk of stroke with odd ratio (OR) = 2.22 and risk ratio = RR 2.47, p < 0.05. Similarly, the VWF-TC genotype and C allele were strongly linked with stroke with OR = 8.12 and RR 4.7, p < 0.05. In addition, GSTT1 and GSTT1 null genotype was strongly associated with stroke predisposition with OR = 8.30 and RR = 2.25, p < 0.0001. We conclude that there is a possible strong association between the VWF-T  > C, TNF-alpha G > A, GSTT1 gene variants and ischemic stroke susceptibility in the Saudi population. However, future well-designed and large-scale case-control studies on protein-protein interactions and protein functional studies are required to verify these findings and examine the effects of these SNPs on these proteins.

The association between HDL-C and stroke in the middle-aged and elderly: A cross-sectional study

BACKGROUND

Previous epidemiological studies have indicated that high-density lipoprotein cholesterol (HDL-C) is inversely associated with the risk of cardiovascular disease. However, this issue has aroused controversy in recent years. Besides, the relationship between HDL-C and the risk of total stroke in sex and race is less clear. Thus, we aimed to examine the association between different ranges of HDL-C and the risk of total stroke in adults over 40 years old.

METHODS

This cross-sectional study was conducted on a sample of 8643 participants (4222 men and 4421 women) aged ≥40 years old from the National Health and Nutrition Examination Survey 2007-2016. HDL-C was an independent variable and stroke was a dependent variable in this study, with the other variables as potential effect modifiers. To examine the associations between them, we used multivariate logistical regression models and smooth curve fittings, as well as subgroup analyses.

RESULTS

HDL-C was inversely associated with stroke when HDL-C was less than 1.55 mmol/L (odds ratio [OR] = 0.36, 95% confidence interval [CI] :0.21-0.62, p < .05). However, above 1.55 mmol/L, the incidence of stroke was not significant (OR = 1.29, 95% CI: 0.79-2.09, p>.05). Stratified by race/ethnicity and sex, the subgroup analyses demonstrated that HDL-C was inversely associated with stroke in men and Whites, but no significant differences among women, Mexicans, blacks, and other races.

CONCLUSION

We found a nonlinear relationship between HDL-C and total stroke. Our study reveals a range of inverse associations between HDL-C and stroke (HDL-C<1.55 mmol/L), especially among men and Whites. This finding suggested that maintaining an appropriate HDL-C range may be beneficial in reducing the incidence of stroke.

Progress of potential drugs targeted in lipid metabolism research

Lipids are a class of complex hydrophobic molecules derived from fatty acids that not only form the structural basis of biological membranes but also regulate metabolism and maintain energy balance. The role of lipids in obesity and other metabolic diseases has recently received much attention, making lipid metabolism one of the attractive research areas. Several metabolic diseases are linked to lipid metabolism, including diabetes, obesity, and atherosclerosis. Additionally, lipid metabolism contributes to the rapid growth of cancer cells as abnormal lipid synthesis or uptake enhances the growth of cancer cells. This review introduces the potential drug targets in lipid metabolism and summarizes the important potential drug targets with recent research progress on the corresponding small molecule inhibitor drugs. The significance of this review is to provide a reference for the clinical treatment of metabolic diseases related to lipid metabolism and the treatment of tumors, hoping to deepen the understanding of lipid metabolism and health.

Cholesterol efflux capacity of HDL was not associated with cognitive decline and brain structures in older people with diabetes mellitus

Aims/Introduction

To examine the association between cholesterol efflux capacity (CEC) of serum high‐density lipoprotein (HDL) and cognitive function and brain structures in older people with diabetes mellitus.

Materials and Methods

Participants of a randomized placebo‐controlled trial of 27‐month vitamin B₁₂ supplementation in older people with diabetes mellitus, which showed no effect on cognition, were further followed up at month 72. Cognitive tests included the Clinical Dementia Rating scale, Neuropsychological Test Battery in memory, executive function and psychomotor speed. Brain magnetic resonance imaging scans were carried out in a subset at baseline, month 27 and month 45. Fasting serum at baseline, month 9, month 27 and month 72 were analyzed for adenosine triphosphate‐binding cassette transporter A1‐mediated CEC of HDL and apolipoprotein A1 (ApoA1).

Results

Serum HDL cholesterol at baseline was associated with better executive and memory function at follow up. Serum ApoA1 was associated with a better memory Z‐score at month 18. Serum CEC and ApoA1 were not associated with Clinical Dementia Rating scale, Neuropsychological Test Battery, hippocampal volume and white matter disease on magnetic resonance imaging at baseline and whole brain atrophy rates. They were also not associated with cognitive function at month 27 and 72 on multilevel modeling. CEC and ApoA1 decreased significantly from baseline to month 27. Faster decliners in CEC had a greater increase in brain peak width of skeletonized mean diffusivity.

Conclusions

Higher serum HDL cholesterol was associated with more favorable changes in memory and executive function in older people with diabetes mellitus. However, this was not due to CEC or ApoA1. A decline in CEC was associated with small vessel disease in the brain.

U-Shaped Relationship of High-Density Lipoprotein Cholesterol and Incidence of Total, Ischemic and Hemorrhagic Stroke: A Prospective Cohort Study

BACKGROUND

We aimed to investigate the association between serially measured HDL-C (high-density lipoprotein cholesterol) levels and stroke risk in a prospective cohort study.

METHODS

We included 96 258 individuals (79.6% men, mean age 51.5 years) without a history of stroke, myocardial infarction, or cancer at baseline from the Kailuan Study, with repeated measurements of HDL-C in 2006, 2008, 2010, 2012, 2014, and 2016. Cumulatively, averaged HDL-C concentrations were calculated using all available HDL-C measurements before incidence stroke or end of follow-up (December 31, 2017). Incident stroke cases were confirmed by review of medical records and further subclassified into ischemic or hemorrhagic stroke. Cox proportional hazards regression and restricted cubic splines were used to examine these associations.

RESULTS

During a median follow-up of 10.7 years, 5012 incident stroke cases occurred. Restricted cubic splines analysis suggested a U-shaped association between concentrations of cumulatively averaged HDL-C and risk of stroke (P_nonlinearity <0.001), with the nadir of risk at 1.29 mmol/L. After adjustment for cardiovascular risk factors, individuals with cumulatively averaged HDL-C ≤1.06 mmol/L or ≥2.05 mmol/L had hazard ratios for total stroke of 1.31 (95% CI, 1.15-1.49) and 1.85 (1.63-2.09) compared with those with HDL-C of 1.26 to 1.39 mmol/L. Corresponding hazard ratios were 1.29 (1.11-1.48) and 1.84 (1.60-2.11) for ischemic stroke and 1.54 (1.12-2.12) and 2.29 (1.73-3.04) for hemorrhagic stroke, respectively.

CONCLUSIONS

Both low and high cumulatively averaged HDL-C were associated with an increased risk of ischemic and hemorrhagic strokes.

New Candidates for Biomarkers and Drug Targets of Ischemic Stroke-A First Dynamic LC-MS Human Serum Proteomic Study

(1) Background: The aim of this dynamic-LC/MS-human-serum-proteomic-study was to identify potential proteins-candidates for biomarkers of acute ischemic stroke, their changes during acute phase of stroke and to define potential novel drug-targets. (2) Methods: A total of 32 patients (29–80 years) with acute ischemic stroke were enrolled to the study. The control group constituted 29 demographically-matched volunteers. Subjects with stroke presented clinical symptoms lasting no longer than 24 h, confirmed by neurological-examination and/or new cerebral ischemia visualized in the CT scans (computed tomography). The analysis of plasma proteome was performed using LC-MS (liquid chromatography–mass spectrometry). (3) Results: Ten proteins with significantly different serum concentrations between groups volunteers were: complement-factor-B, apolipoprotein-A-I, fibronectin, alpha-2-HS-glycoprotein, alpha-1B-glycoprotein, heat-shock-cognate-71kDa protein/heat-shock-related-70kDa-protein-2, thymidine phosphorylase-2, cytoplasmic-tryptophan-tRNA-ligase, ficolin-2, beta-Ala-His-dipeptidase. (4) Conclusions: This is the first dynamic LC-MS study performed on a clinical model which differentiates serum proteome of patients in acute phase of ischemic stroke in time series and compares to control group. Listed proteins should be considered as risk factors, markers of ischemic stroke or potential therapeutic targets. Further clinical validation might define their exact role in differential diagnostics, monitoring the course of the ischemic stroke or specifying them as novel drug targets.

Management of Dyslipidaemia for the Prevention of Stroke: Clinical Practice Recommendations from the Lipid Association of India

Stroke is the second most common cause of death worldwide. The rates of stroke are increasing in less affluent countries predominantly because of a high prevalence of modifiable risk factors. The Lipid Association of India (LAI) has provided a risk stratification algorithm for patients with ischaemic stroke and recommended low density lipoprotein cholesterol (LDL-C) goals for those in a very high risk group and extreme risk group (category A) of <50 mg/dl (1.3 mmol/l) while the LDL-C goal for extreme risk group (category B) is ≤30 mg/dl (0.8 mmol/l). High intensity statins are the first-line lipid lowering therapy. Non-statin therapy like ezetimibe and proprotein convertase subtilisin kexin type 9 (PCSK9) inhibitors may be added as an adjunct to statins in patients who do not achieve LDL-C goals statins alone. In acute ischaemic stroke, high intensity statin therapy improves neurological and functional outcomes regardless of thrombolytic therapy. Although conflicting data exist regarding increased risk of intracerebral haemorrhage (ICH) with statin use, the overall benefit risk ratio favors long-term statin therapy necessitating detailed discussion with the patient. Patients who have statins withdrawn while being on prior statin therapy at the time of acute ischaemic stroke have worse functional outcomes and increased mortality. LAI recommends that statins be continued in such patients. In patients presenting with ICH, statins should not be started in the acute phase but should be continued in patients who are already taking statins. ICH patients, once stable, need risk stratification for atherosclerotic cardiovascular disease (ASCVD).

High density lipoprotein in atherosclerosis and coronary heart disease: Where do we stand today?

Epidemiological studies during the last five years suggest that a relation between high density lipoprotein cholesterol (HDL-C) levels and the risk for cardiovascular disease (CVD) does exist but follows rather a "U-shaped" curve with an optimal range of HDL-C concentration between 40 and 70 mg/dl for men and 50-70 mg/dl for women. Moreover, as research in the field of lipoproteins progresses it becomes increasingly apparent that HDL particles possess different attributes and depending on their structural and functional characteristics, they may be "antiatherogenic" or "proatherogenic". In light of this information, it is highly doubtful that the choice of experimental drugs and the design of respective clinical trials that put the HDL-C raising hypothesis at test, were the most suitable. Here, we compile the existing literature on HDL, providing a critical up-to-date view that focuses on key data from the biochemistry, epidemiology and pharmacology of HDL, including data from clinical trials. We also discuss the most up-to-date information on the contribution of HDL structure and function to the prevention of atherosclerosis. We conclude by summarizing important differences between mouse models and humans, that may explain why pharmacological successes in mice turn out to be failures in humans.

The association between serine hydroxymethyl transferase 1 gene hypermethylation and ischemic stroke

This study aimed to determine the correlation between serine hydroxymethyl transferase 1 (SHMT1) gene methylation and ischemic stroke. A total of 202 age- and sex-matched individuals were included. Quantitative methylation-specific polymerase chain reaction (qMSP-PCR) was used to analyze the DNA methylation level. The plasma homocysteine (Hcy) concentration was much higher in ischemic cases than in controls (p = 0.009), while the high-density lipoprotein (HDL) levels in stroke cases were considerably lower than in controls (p = 0.005). A significantly higher level of SHMT1 methylation was observed in the ischemic strokes (58.82 ± 17.83%) compared to that in the controls (42.59 ± 20.76%, p < 0.001). The SHMT1 methylation level was strongly correlated with HDL concentration in the healthy controls (r = 0.517, p < 0.001), while the high plasma level of Hcy showed strong association with SHMT1 methylation in ischemic strokes (r = 0.346, p < 0.001). Receiver operating characteristic (ROC) analysis of curve indicated that SHMT1 methylation has been an acceptable indicator for ischemic stroke in female patients [all sexes, area under the curve (AUC) = 0.71, p < 0.001; male patients AUC = 0.62, p = 0.032; and female patients AUC = 0.79, p < 0.001] and in all ages (AUC = 0.71, p < 0.001). In our samples, DNA methylation levels of the STHMI gene were significantly correlated with ischemic stroke in Han Chinese. STHMI hypermethylation was significantly associated with the high Hcy concentration in ischemic stroke and had value as a potential indicator for female ischemic stroke.

Additive interaction between potentially modifiable risk factors and ethnicity among individuals in the Han, Tujia and Miao populations with first-ever ischaemic stroke

BACKGROUND

As a country with one-fifth of the global population, China has experienced explosive growth in ischaemic stroke (IS) burden with significant ethnic and geographic disparities. The aim of this study was to examine the differences in potentially modifiable risk factors for ischaemic stroke among the Han population and two ethnic minorities (Tujia and Miao).

METHODS

A case-control study was conducted with 324 cases of first-ever ischaemic stroke from the hospitals of the Xiangxi Tujia and Miao Autonomous Prefecture and 394 controls from communities covering the same area between May 1, 2018, and April 30, 2019. Structured questionnaires were administered, and physical examinations were performed in the same manner for cases and controls. Univariate and multivariate logistic regression analyses with adjusted odds ratios (ORs) and 95% confidence intervals (CIs) were used to examine the association between risk factors and ischaemic stroke. An additive model was used to study the interaction between the modifiable risk factors and ethnicity with R software.

RESULTS

Higher high-sensitivity C-reactive protein levels (OR 50.54, 95%CI 29.76-85.85), higher monthly family income (4.18, 2.40-7.28), increased frequency of hot pot consumption (2.90, 1.21-6.93), diabetes mellitus (2.62, 1.48-4.62), a higher apolipoprotein (Apo)B/ApoA1 ratio (2.60, 1.39-4.85), hypertension (2.52, 1.45-4.40) and moderate-intensity physical activity (0.50, 0.28-0.89) were associated with ischaemic stroke. There was an additive interaction between the ApoB/ApoA1 ratio and ethnicity in the Tujia and Miao populations with first-ever ischaemic stroke (the relative excess risk due to the interaction was 5.75, 95% CI 0.58 ~ 10.92; the attributable proportion due to the interaction was 0.65, 95% CI 0.38 ~ 0.91; the synergy index was 3.66, 95% CI 1.35 ~ 9.93).

CONCLUSIONS

This is the first case-control study examining modifiable risk factors for ischaemic stroke among the Han population and two ethnic minorities (Tujia and Miao) in China. Some differences were observed in the impact of risk factors among these ethnic groups. Our results may help interpret health-related data, including surveillance and research, when developing strategies for stroke prevention.

Dose-Response Association Between High-Density Lipoprotein Cholesterol and Stroke: A Systematic Review and Meta-Analysis of Prospective Cohort Studies

INTRODUCTION

Studies investigating the effect of high-density lipoprotein cholesterol (HDL-C) on stroke and stroke subtypes have reached inconsistent conclusions. The purpose of our study was to clarify the dose-response association between HDL-C level and risk of total stroke and stroke subtypes by a systematic review and meta-analysis.

METHODS

We performed a systematic search of PubMed, Embase, and Web of Science databases through July 30, 2020, for prospective cohort studies that reported the HDL-C-stroke association and extracted the estimate that was adjusted for the greatest number of confounding factors. Restricted cubic splines were used to evaluate the linear and nonlinear dose-response associations.

RESULTS

We included 29 articles, which reported on 62 prospective cohort studies including 900,501 study participants and 25,678 with stroke. The summary relative risk per 1-mmol/L increase in HDL-C level for total stroke was 0.82 (95% CI, 0.76-0.89; I² = 42.9%; n = 18); ischemic stroke (IS), 0.75 (95% CI, 0.69-0.82; I² = 50.1%; n = 22); intracerebral hemorrhage (ICH), 1.21 (95% CI, 1.04-1.42; I² = 33.4%; n = 10); and subarachnoid hemorrhage (SAH), 0.98 (95% CI, 0.96-1.00; I² = 0%; n = 7). We found a linear inverse association between HDL-C level and risk of total stroke and SAH, a nonlinear inverse association for IS risk, but a linear positive association for ICH risk. The strength and the direction of the effect size estimate for total stroke, IS, ICH, and SAH remained stable for most subgroups. We found no publication bias with Begg's test and Egger's test for the association of HDL-C level with risk of total stroke, IS, and ICH.

CONCLUSION

A high HDL-C level is associated with reduced risk of total stroke and IS and an increased risk of ICH.

The Endothelium Is Both a Target and a Barrier of HDL's Protective Functions

The vascular endothelium serves as a barrier between the intravascular and extravascular compartments. High-density lipoproteins (HDL) have two kinds of interactions with this barrier. First, bloodborne HDL must pass the endothelium to access extravascular tissues, for example the arterial wall or the brain, to mediate cholesterol efflux from macrophages and other cells or exert other functions. To complete reverse cholesterol transport, HDL must even pass the endothelium a second time to re-enter circulation via the lymphatics. Transendothelial HDL transport is a regulated process involving scavenger receptor SR-BI, endothelial lipase, and ATP binding cassette transporters A1 and G1. Second, HDL helps to maintain the integrity of the endothelial barrier by (i) promoting junction closure as well as (ii) repair by stimulating the proliferation and migration of endothelial cells and their progenitor cells, and by preventing (iii) loss of glycocalix, (iv) apoptosis, as well as (v) transmigration of inflammatory cells. Additional vasoprotective functions of HDL include (vi) the induction of nitric oxide (NO) production and (vii) the inhibition of reactive oxygen species (ROS) production. These vasoprotective functions are exerted by the interactions of HDL particles with SR-BI as well as specific agonists carried by HDL, notably sphingosine-1-phophate (S1P), with their specific cellular counterparts, e.g., S1P receptors. Various diseases modify the protein and lipid composition and thereby the endothelial functionality of HDL. Thorough understanding of the structure-function relationships underlying the multiple interactions of HDL with endothelial cells is expected to elucidate new targets and strategies for the treatment or prevention of various diseases.

[Plasma high density lipoproteins phospholipds as an indirect indicator of their cholesterol efflux capacity - new suspected atherosclerosis risk factor]

High density lipoproteins (HDL) are a unique natural structure, protecting the body from the development of atherosclerotic vascular lesions and cardiovascular diseases due to this ability to remove cholesterol from cells. Plasma HDL level estimated by their cholesterol content, is a common lipid parameter, and its decrease is considered as an established atherosclerosis risk factor. However, a number of studies have shown the absence of positive clinical effects after drug-induced increase in HDL cholesterol. There is increasing evidence that not only HDL concentration, but also HDL properties, considered in this review are important. Many studies showed the decrease of HDL cholesterol efflux capacity in patients with coronary heart diseases and its association with disease severity. Some authors consider a decrease of this HDL capacity as a new additional risk factor of atherosclerosis. The review summarizes existing information on various protein and lipid components of HDL with a primary emphasis on the HDL. Special attention is paid to correlation between the HDL cholesterol efflux capacity and HDL phospholipids and the ratio "phospholipids/free cholesterol". The accumulated information indicates importance of evaluation in the HDL fraction not only in terms of their cholesterol, but also phospholipids. In addition to the traditionally used lipid criteria, this would provide more comprehensive information about the activity of the reverse cholesterol transport process in the body and could contribute to the targeted correction of the detected disorders.

The loss-of-function mutation of CETP affects HDLc levels but not ApoA1 in patients with acute myocardial infarction

BACKGROUND AND AIMS

Loss of the cholesteryl ester transfer protein (CETP) function affects HDLc levels, but its effects on major HDL protein component ApoA1 are not well understood in patients with acute myocardial infarction (AMI).

METHODS AND RESULTS

We investigated the effects of an East Asian loss-of-function variant (rs2303790; p.D442G) in CETP gene on HDLc and ApoA1 levels and its relationship with AMI. A total of 2327 AMI patients and 2615 age- and sex-matched controls from INTERHEART-China study were included. In controls, both levels of HDLc (1.24 vs. 1.04 mmol/L, P = 0.001) and ApoA1 (1.48 vs. 1.37 mmol/L, P = 0.042) were significantly higher in CETP variant G allele carriers compared to CETP wildtype D allele carriers. In AMI patients, levels of HDLc were significantly higher (1.14 vs. 1.01 mmol/L, P = 0.013) while levels of ApoA1 were not statistically difference (1.31 vs. 1.32 mmol/L, P = 0.468) in CETP variant group compared to CETP wildtype group. Moreover, CETP variant is associated with HDLc increase, but is not associated with AMI risk (P = 0.564), even after adjusting for age, sex, history of hypertension and diabetes, waist to hip ratio, smoking, total cholesterol, LDL cholesterol, triglycerides, physical activity, depression, alcohol, vegetables and fruit consumption.

CONCLUSIONS

Loss of CETP function is associated with increased HDLc and ApoA1 levels in healthy subjects, and in AMI patients, it is associated with HDLc levels but not ApoA1 levels. The lack of association of CETP variant with AMI may be related to the inability to increase ApoA1 levels and warranted further studies.

Delayed retinal vein recovery responses indicate both non-adaptation to stress as well as increased risk for stroke: the SABPA study

OBJECTIVES

Low or high sympatho-adrenal-medullary axis (SAM) and hypothalamic-pituitary-adrenal axis (HPA) dysregulation reflect chronic stress. Retinal vessel dynamics may relate to SAM, HPA activity and stroke risk. Our objectives were therefore to assess the relationships between retinal vessel, SAM and HPA responses, and to determine stroke risk.

METHODS

A prospective bi-ethnic gender cohort (n = 275, 45 ± 9 years) was included. Urine/serum/saliva samples for SAM [norepinephrine:creatinine ratio (u-NE)] and HPA [adrenocorticotrophic hormone (ACTH), cortisol] were obtained at baseline, three-year follow up and upon flicker light-induced provocation. Diastolic ocular perfusion pressure was measured as a marker of hypo-perfusion. Retinal arterial narrowing and venous widening calibres were quantified from digital images in the mydriatic eye. A validated stress and stroke risk score was applied.

RESULTS

An interaction term was fitted for venous dilation in u-NE tertiles (p ≤ 0.05) and not in u-NE median/quartiles/quintiles. Independent of race or gender, tertile 1 (low u-NE) had a 112% increase in u-NE, decreases in cortisol, and no changes in ACTH over three years (positive feedback). Tertile 3 (high u-NE) contradictorily had decreases in u-NE and cortisol, and increases in ACTH (negative feedback). In tertile 1, reduced arterial dilation, and faster arterial vasoconstriction and narrowing were related to higher SAM activity and hypo-perfusion (p ≤ 0.05), whereas delayed venous dilation, recovery and widening were related to cortisol hypo-secretion (p ≤ 0.05). In tertile 1, delayed venous recovery responses predicted stress and stroke risk [odds ratio 4.8 (1.2-19.6); p = 0.03]. These associations were not found in u-NE tertiles 2 and 3.

CONCLUSIONS

In response to low norepinephrine, a reflex increase in SAM activity occurred, enhancing arterial vasoconstriction and hypo-perfusion. Concomitant HPA dysregulation attenuated retinal vein vasoactivity and tone, reflecting delayed vein recovery responses and non-adaptation to stress. These constrained vein recovery responses are indicative of increased chronic stress and stroke risk.

Inflammatory markers as independent predictors for stroke outcomes

BACKGROUND

Inflammation plays an important role in the pathophysiology of stroke. The aim of the present study was to investigate the association between various inflammatory risk markers and ischemic stroke outcome and subtype.

METHODS

A total of 3,013 ischemic stroke patients who were admitted to our hospital from 01/01/2016 to 12/30/2018 were retrospectively studied. Stroke subtypes were defined by the Trial of Org 10172 in Acute Stroke Treatment (TOAST) classification. Levels of five common inflammatory markers including white blood cell (WBC) count, neutrophil, lymphocyte, serum C-reactive protein (CRP), and interleukin-6 (IL-6) were measured, and eleven conventional risk factors were further evaluated in the prediction of overall mortality as well as three functional outcomes defined by the National Institute of Health Stroke Scale (NIHSS), the modified Rankin Scale (mRS), and the Barthel Index (BI). Independent predictors of outcome were identified by multivariate logistic regression, and an importance score measured by the area under the receiver operating characteristics curve for each predictor using a Naive Bayes model was reported.

RESULTS

Neutrophil and WBC were significantly higher in large-artery atherosclerosis (LAA) and cardioembolism (CE) subtype. In contrast, lymphocyte was significantly higher in small-artery occlusion (SAO). Neutrophil-lymphocyte ratio and CRP level were the best independent predictors, after adjustment for traditional risk factors and TOAST subtype for all four types of outcomes.

CONCLUSION

Inflammatory risk markers including neutrophil, lymphocyte, and CRP may have strong independent prediction values for stroke outcome.

Danger-Sensing/Patten Recognition Receptors and Neuroinflammation in Alzheimer's Disease

Fibrillar aggregates and soluble oligomers of both Amyloid-β peptides (Aβs) and hyperphosphorylated Tau proteins (p-Tau-es), as well as a chronic neuroinflammation are the main drivers causing progressive neuronal losses and dementia in Alzheimer’s disease (AD). However, the underlying pathogenetic mechanisms are still much disputed. Several endogenous neurotoxic ligands, including Aβs, and/or p-Tau-es activate innate immunity-related danger-sensing/pattern recognition receptors (PPRs) thereby advancing AD’s neuroinflammation and progression. The major PRR families involved include scavenger, Toll-like, NOD-like, AIM2-like, RIG-like, and CLEC-2 receptors, plus the calcium-sensing receptor (CaSR). This quite intricate picture stresses the need to identify the pathogenetically topmost Aβ-activated PRR, whose signaling would trigger AD’s three main drivers and their intra-brain spread. In theory, the candidate might belong to any PRR family. However, results of preclinical studies using in vitro nontumorigenic human cortical neurons and astrocytes and in vivo AD-model animals have started converging on the CaSR as the pathogenetically upmost PRR candidate. In fact, the CaSR binds both Ca²⁺ and Aβs and promotes the spread of both Ca²⁺ dyshomeostasis and AD’s three main drivers, causing a progressive neurons’ death. Since CaSR’s negative allosteric modulators block all these effects, CaSR’s candidacy for topmost pathogenetic PRR has assumed a growing therapeutic potential worth clinical testing.

High-Density Lipoprotein Carries Markers That Track With Recovery From Stroke

RATIONALE

Prospective cohort studies question the value of HDL-C (high-density lipoprotein cholesterol) for stroke risk prediction.

OBJECTIVE

Investigate the relationship between long-term functional recovery and HDL proteome and function.

METHODS AND RESULTS

Changes in HDL protein composition and function (cholesterol efflux capacity) in patients after acute ischemic stroke at 2 time points (24 hours, 35 patients; 96 hours, 20 patients) and in 35 control subjects were measured. The recovery from stroke was assessed by 3 months, the National Institutes of Health Stroke Scale and modified Rankin scale scores. When compared with control subject after adjustments for sex and HDL-C levels, 12 proteins some of which participate in acute phase response and platelet activation (APMAP [adipocyte plasma membrane-associated protein], GPLD1 [phosphate inositol-glycan specific phospholipase D], APOE [apolipoprotein E], IHH [Indian hedgehog protein], ITIH4 [inter-alpha-trypsin inhibitor chain H4], SAA2 [serum amyloid A2], APOA4 [apolipoprotein A-IV], CLU [clusterin], ANTRX2 [anthrax toxin receptor 2], PON1 [serum paraoxonase/arylesterase], SERPINA1 [alpha-1-antitrypsin], and APOF [apolipoprotein F]) were significantly (adjusted P<0.05) altered in stroke HDL at 96 hours. The first 8 of these proteins were also significantly altered at 24 hours. Consistent with inflammatory remodeling, cholesterol efflux capacity was reduced by 32% (P<0.001) at both time points. Baseline stroke severity adjusted regression model showed that changes within 96-hour poststroke in APOF, APOL1, APMAP, APOC4 (apolipoprotein C4), APOM (apolipoprotein M), PCYOX1 (prenylcysteine oxidase 1), PON1, and APOE correlate with stroke recovery scores (R2=0.38-0.73, adjusted P<0.05). APOF (R2=0.73) and APOL1 (R2=0.60) continued to significantly correlate with recovery scores after accounting for tPA (tissue-type plasminogen activator) treatment.

CONCLUSIONS

Changes in HDL proteins during early acute phase of stroke associate with recovery. Monitoring HDL proteins may provide clinical biomarkers that inform on stroke recuperation.

The role of monocyte to HDL ratio in predicting clinically significant carotid stenosis in patients with asymptomatic carotid artery disease

OBJECTIVE

Monocyte count to HDL-C Ratio (MHR) and Fibrinogen to Albumin Ratio (FAR) have recently emerged as markers of inflammation in atherosclerotic diseases. Our goal was to investigate the relationships of MHR and FAR with the severity of carotid artery stenosis (CAS) in patients with asymptomatic carotid artery disease.

METHODS

This retrospective study consisted of 300 patients with asymptomatic CAS. Pre-angiographic MHR, FAR, and high-sensitive C-reactive protein (hsCRP) were measured. Carotid angiography was performed in patients with ≥50% stenosis on carotid ultrasonography. Patients were first split into 2 groups based on the degree of CAS and then tertiles (T) of MHR.

RESULTS

96 patients had clinically insignificant CAS (<50%) (Group-1), and 204 patients had clinically significant CAS (≥50%) (Group-2). Group-2 had higher MHR, FAR, and hsCRP than group-1. Patients in T3 had higher MHR, FAR, and hsCRP than in T1 and T2. MHR, FAR, and hsCRP were correlated with each other (p<0.001, for all). MHR, FAR, and hsCRP were independent predictors of significant CAS. MHR better predicted a significant CAS than FAR and hsCRP (p<0.05).

CONCLUSION

Pre-angiographic MHR may be a better predictor than FAR and hsCRP in identifying a clinically significant carotid stenosis in patients with asymptomatic CAS. Patients with asymptomatic CAS and a high level of MHR should be followed-up closely to supervise risk-factor control and intensify treatment.

[The Risk of Developing Ischemic Stroke in Patients After Exacerbation of Ischemic Heart Disease]

Aim      To develop a model for evaluating the risk of stroke in patients after exacerbation of ischemic heart disease who were admitted to the hospitals included into a vascular program.Materials and methods This study included 1803 patients with acute coronary syndrome (ACS) from four institutions of Moscow, Kazan, Astrakhan, and Krasnodar where the vascular program was established. Mean age of patients was 64.9±12.78 years, 62,1 % of them were men. The patients were followed up for one year after the discharge from the hospital. External validation of the developed prognostic model was performed on a cohort of patients with ACS included into the RECORD-3 study.Results During the follow-up period, 42 cases of ischemic stroke were observed. The risk of ischemic stroke was associated with the presence of atrial fibrillation (odd ratio (OR) 2.640; р=0.037), diabetes mellitus (OR 2.718; р=0.041), and chronic heart failure (OR 7.049; р=0.011). Protective factors were high-density lipoprotein cholesterol &gt;1 mmol/l (OR 0.629; р=0.041), percutaneous coronary intervention during an index hospitalization (OR 0.412; р=0.042), anticoagulant treatment (OR 0.670; р=0.049), and achieving the blood pressure goal (OR 0.604; р=0.023). The prognostic model developed on the basis of regression analysis showed a good predictive value (area under the ROC curve, 0.780), sensitivity of 80 %, and specificity of 64.6 %. The diagnostic value of other scales for risk assessment was somewhat lower. The area under the ROC curve was 0.692±0.0245 for the GRACE scale and 0.708±0.0334 for CHA2DS2‑VASc. In the external validation of the scale based on data of the RECORD-3 study, the diagnostic value was lower although satisfactory as well (area under the ROC curve, 0.651); sensitivity was 78.9 %, and specificity was 52.3 %.Conclusion      The study resulted in development of a simple clinical scale, which will probably allow identifying groups at risk of stroke more precisely than with standard scales.

PON1 Hypermethylation and PON3 Hypomethylation are Associated with Risk of Cerebral Infarction

OBJECTIVE

Paraoxonase (PON) family genes are closely related to the etiology and prognosis of cerebral infarction. This study explored the association of the promoter methylation of PON family genes (PON1, PON2 and PON3) with the risk of cerebral infarction.

MATERIALS AND METHODS

In this study, 152 patients with confirmed cerebral infarction were selected as the case group, and 152 healthy controls were selected as the control group. The quantitative methylation-specific PCR (qMSP) was used to determine the promoter methylation levels of PON1, PON2 and PON3 genes. The methylation level was expressed as a methylation reference percentage (PMR).

RESULTS

Our results indicated that PON1 methylation was significantly higher in the case group than in the control group (P = 0.0001). On the contrary, PON3 methylation was significantly lower in the case group than in the control group (P = 0.002). In addition, we found that PON2 gene had a very low level of methylation in both case and control groups (PMR = 0). Subgroup analysis showed that PON1 and PON3 methylation were associated with cerebral infarction only in males (PON1, P = 0.0002; PON3, P = 0.007). Interestingly, the methylation levels of PON1 and PON3 were correlated with each other (case: r = 0.418, P = 0.0001; control: r = 0.3, P = 0.0002). Further multiple regression analysis suggested that elevated methylation levels of PON3 were a protective factor for cerebral infarction [OR (95%CI) = 0.979 (0.96, 0.999), β = -0.021, P = 0.035)], highdensity lipoprotein (HDL) and uric acid (UA) also were protective factors for cerebral infarction [HDL, OR (95% CI) = 0.01 (0.003, 0.033), P < 0.0001); UA, OR (95% CI) = 0.995 (0.991, 0.998), P = 0.003)]. The ROC curve analysis found that the combination of PON3, HDL, and UA had a good predictive power for cerebral infarction (AUC=0.878, 95% CI=0.839-0.918, sensitivity 73.7%, specificity 89.7%, P < 0.0001).

CONCLUSION

PON1 and PON3 promoter methylation levels in peripheral blood were closely related. PON1 and PON3 methylation were associated with the risk of cerebral infarction in men. PON3 promoter methylation combined with HDL and UA could be used as potential biomarkers for the diagnosis of cerebral infarction.

Association of Waist-to-Height Ratio, Metabolic Syndrome, and Carotid Atherosclerosis in Individuals with a High Risk of Stroke: A Cross-Sectional Study of 9605 Study Participants

Background: To determine the association of waist-to-height ratio (WHtR), metabolic syndrome (MetS), and carotid atherosclerosis (CAS) in individuals with a high risk of stroke. Methods: We performed a cross-sectional analysis of 9605 study responders from eight urban area communities in Northern China. Height, weight, waist circumference, blood pressure (BP), and blood lipid were measured. Information of population characteristics, smoking status, alcohol consumption, physical activity, and diet were determined by validated questionnaire. Results: A total of 9605 study responders were included in this study. The average age was 60 ± 9 years with 5911 (61.5%) patients being females. The prevalence of MetS and CAS was 26.2% and 75.1%, respectively. WHtR was significantly associated with CAS using our final adjusted model [odds ratio (OR): 1.233, 95% confidence interval (CI): 1.096-1.378]. The association of CAS with hypertension and hyperglycemia were statistically significant among factors that constitute MetS. Additional risk factors affecting the development of CAS included age, previous stroke, and smoking history (P < 0.05). Conclusion: WHtR was determined to perform better compared with other traditional indicators for correlating CAS. We believe that WHtR is a better indicator for the early identification of CAS in individuals with a high risk of stroke. This will facilitate the early detection and intervention of CAS.

Monocyte to high-density lipoprotein ratio and cardiovascular events in patients on peritoneal dialysis

BACKGROUND AND AIMS

The monocyte to high-density lipoprotein cholesterol ratio (MHR) is associated with multiple cardiovascular diseases. However, the role of the MHR in predicting cardiovascular diseases in patients on peritoneal dialysis remains unclear.

METHODS AND RESULTS

Eight hundred and eighty incident peritoneal dialysis patients were enrolled from November 1, 2005, to February 28, 2017, and followed until May 31, 2017. Primary outcomes were cardiovascular events. Using the X-tile program, these patients were divided into three groups according to the MHR. Kaplan-Meier method and Cox regressions were used for survival analysis. During a median follow-up period of 26 months (interquartile range: 12-39 months), 139 cardiovascular events were recorded. After multiple adjustment, the high MHR group was associated with a 1.97-fold increase in the cardiovascular events hazard compared to that of the low group in the overall population (hazard ratio: 1.97; 95% CI, 1.19-3.28; P = 0.009). Subgroup analysis demonstrated that the association between the MHR and a higher risk of cardiovascular events was strongest in the subgroup of patients with diabetes (P for interaction = 0.004). In this subgroup, the high MHR group was found to be associated with a higher risk of cardiovascular events compared to the low group (hazard ratio: 7.69; 95% CI, 2.76-21.47).

CONCLUSION

This study suggests that the MHR is independently associated with the risk of cardiovascular events in patients undergoing peritoneal dialysis, and diabetes status can influence the association between the MHR and the risk of cardiovascular events.

Associations Between High-Density Lipoprotein Particles and Ischemic Events by Vascular Domain, Sex, and Ethnicity: A Pooled Cohort Analysis

Supplemental Digital Content is available in the text.

Background:

High-density lipoprotein (HDL) cholesterol concentration (HDL-C) is an established atheroprotective marker, in particular for coronary artery disease; however, HDL particle concentration (HDL-P) may better predict risk. The associations of HDL-C and HDL-P with ischemic stroke and myocardial infarction (MI) among women and Blacks have not been well studied. We hypothesized that HDL-P would consistently be associated with MI and stroke among women and Blacks compared with HDL-C.

Methods:

We analyzed individual-level participant data in a pooled cohort of 4 large population studies without baseline atherosclerotic cardiovascular disease: DHS (Dallas Heart Study; n=2535), ARIC (Atherosclerosis Risk in Communities; n=1595), MESA (Multi-Ethnic Study of Atherosclerosis; n=6632), and PREVEND (Prevention of Renal and Vascular Endstage Disease; n=5022). HDL markers were analyzed in adjusted Cox proportional hazard models for MI and ischemic stroke.

Results:

In the overall population (n=15 784), HDL-P was inversely associated with the combined outcome of MI and ischemic stroke, adjusted for cardiometabolic risk factors (hazard ratio [HR] for quartile 4 [Q4] versus quartile 1 [Q1], 0.64 [95% CI, 0.52–0.78]), as was HDL-C (HR for Q4 versus Q1, 0.76 [95% CI, 0.61–0.94]). Adjustment for HDL-C did not attenuate the inverse relationship between HDL-P and atherosclerotic cardiovascular disease, whereas adjustment for HDL-P attenuated all associations between HDL-C and events. HDL-P was inversely associated with the individual end points of MI and ischemic stroke in the overall population, including in women. HDL-P was inversely associated with MI among White participants but not among Black participants (HR for Q4 versus Q1 for Whites, 0.49 [95% CI, 0.35–0.69]; for Blacks, 1.22 [95% CI, 0.76–1.98]; P_interaction=0.001). Similarly, HDL-C was inversely associated with MI among White participants (HR for Q4 versus Q1, 0.53 [95% CI, 0.36–0.78]) but had a weak direct association with MI among Black participants (HR for Q4 versus Q1, 1.75 [95% CI, 1.08–2.83]; P_interaction<0.0001).

Conclusions:

Compared with HDL-C, HDL-P was consistently associated with MI and ischemic stroke in the overall population. Differential associations of both HDL-C and HDL-P for MI by Black ethnicity suggest that atherosclerotic cardiovascular disease risk may differ by vascular domain and ethnicity. Future studies should examine individual outcomes separately.

Incorporating sampling weights into robust estimation of Cox proportional hazards regression model, with illustration in the Multi-Ethnic Study of Atherosclerosis

BACKGROUND

Cox proportional hazards regression models are used to evaluate associations between exposures of interest and time-to-event outcomes in observational data. When exposures are measured on only a sample of participants, as they are in a case-cohort design, the sampling weights must be incorporated into the regression model to obtain unbiased estimating equations.

METHODS

Robust Cox methods have been developed to better estimate associations when there are influential outliers in the exposure of interest, but these robust methods do not incorporate sampling weights. In this paper, we extend these robust methods, which already incorporate influence weights, so that they also accommodate sampling weights.

RESULTS

Simulations illustrate that in the presence of influential outliers, the association estimate from the weighted robust method is closer to the true value than the estimate from traditional weighted Cox regression. As expected, in the absence of outliers, the use of robust methods yields a small loss of efficiency. Using data from a case-cohort study that is nested within the Multi-Ethnic Study of Atherosclerosis (MESA) longitudinal cohort study, we illustrate differences between traditional and robust weighted Cox association estimates for the relationships between immune cell traits and risk of stroke.

CONCLUSIONS

Robust weighted Cox regression methods are a new tool to analyze time-to-event data with sampling, e.g. case-cohort data, when exposures of interest contain outliers.

Paraoxonase 1 and atherosclerosis-related diseases

A direct and an indirect relationship between paraoxonase 1 (PON1) and atherosclerosis exists. Given PON1's physical location within high-density lipoprotein (HDL) particles and its recognized enzyme activity, it is certainly reasonable to suggest that PON1 facilitates the antiatherogenic nature of HDL particles. PON1 also plays a role in regulating reverse cholesterol transport, antioxidative, anti-inflammatory, antiapoptotic, vasodilative, and antithrombotic activities and several endothelial cell functions. HDL dysfunctionality is a more recent issue and seems to be centered on pathological conditions affecting HDL structure and size profiles. This review is focused on the role of PON1 status in different atherosclerosis-related diseases that we have studied over the last twenty years (coronary heart disease, acute ischemic stroke, diabetes mellitus type 2, end-stage renal disease, chronic obstructive pulmonary disease, and sarcoidosis) with the aim to determine the true value of PON1 as a biomarker. The role of PON1 in cancer is also covered, as risk factors and mechanisms underlying both atherosclerosis and cancer share common features.

Postprandial remodeling of high-density lipoprotein following high saturated fat and high carbohydrate meals

BACKGROUND

Humans spend most of the time in the postprandial state, yet most knowledge about high-density lipoproteins (HDL) derives from the fasted state. HDL protein and lipid cargo mediate HDL's antiatherogenic effects, but whether these HDL constituents change in the postprandial state and are affected by dietary macronutrients remains unknown.

OBJECTIVES

This study aimed to assess changes in HDL protein and lipid composition after the consumption of a high-carbohydrate or high saturated fat (HSF) meal.

METHODS

We isolated HDL from plasma collected during a randomized, cross-over study of metabolically healthy subjects. Subjects consumed isocaloric meals consisting predominantly of either carbohydrate or fat. At baseline and at 3 and 6 hours postprandial, we quantified HDL protein and lipid composition by liquid chromatography-mass spectrometry.

RESULTS

A total of 15 subjects were included (60% female, aged 34 ± 15 years, body mass index: 24.1 ± 2.7 kg/m2). Consumption of the HSF meal led to HDL enrichment in total lipid (P = .006), triglyceride (P = .02), and phospholipid (P = .008) content and a corresponding depletion in protein content. After the HSF meal, 16 of the 25 measured phosphatidylcholine species significantly increased in abundance (P values range from .027 to <.001), along with several sphingolipids including ceramides (P < .004), lactosylceramide (P = .023), and sphingomyelin-14 (P = .013). Enrichment in apolipoprotein A-I (P = .001) was the only significant change in HDL protein composition after the HSF meal. The high-carbohydrate meal conferred only minimal changes in HDL composition.

CONCLUSION

Meal macronutrient content acutely affects HDL composition in the postprandial state, with the HSF meal resulting in enrichment of HDL phospholipid content with possible consequences for HDL function.

Scavenger Receptor Class B type 1 (SR-B1) and the modifiable risk factors of stroke

Stroke is a devastating disease that occurs when a blood vessel in the brain is either blocked or ruptured, consequently leading to deficits in neurological function. Stroke consistently ranked as one of the top causes of mortality, and with the mean age of incidence decreasing, there is renewed interest to seek novel therapeutic treatments. The Scavenger Receptor Class B type 1 (SR-B1) is a multifunctional protein found on the surface of a variety of cells. Research has found that that SR-B1 primarily functions in an anti-inflammatory and anti-atherosclerotic capacity. In this review, we discuss the characteristics of SR-B1 and focus on its potential correlation with the modifiable risk factors of stroke. SR-B1 likely has an impact on stroke through its interaction with smoking, diabetes mellitus, diet, physical inactivity, obesity, hypercholesterolemia, atherosclerosis, coronary heart disease, hypertension, and sickle cell disease, all of which are critical risk factors in the pathogenesis of stroke.

Inverse Association Between HDL (High-Density Lipoprotein) Cholesterol and Stroke Risk Among Patients With Type 2 Diabetes Mellitus

Background and Purpose- Few studies have assessed the association of HDL (high-density lipoprotein) cholesterol with stroke risk among patients with type 2 diabetes mellitus. We aimed to investigate the association of HDL cholesterol with total and type-specific stroke risk in patients with type 2 diabetes mellitus. Methods- We performed a retrospective cohort study of 27 113 blacks and 40 431 whites with type 2 diabetes mellitus. Cox proportional hazards regression models were used to estimate the association of different levels of HDL cholesterol with stroke risk. Results- During a mean follow-up period of 3.0 years, 8496 patients developed stroke (8048 ischemic and 448 hemorrhagic). Multivariable-adjusted hazard ratios across levels of HDL at baseline (<30 [reference group], 30-39.9, 40-49.9, 50-59.9, 60-69.9, 70-79.9, and ≥80 mg/dL) were 1.00, 0.86, 0.77, 0.71, 0.71, 0.77, and 0.69 ( P_trend <0.001) for total stroke, 1.00, 0.89, 0.82, 0.75, 0.78, 0.76, and 0.75 ( P_trend <0.001) for ischemic stroke, and 1.00, 0.89, 0.69, 0.66, 0.47, and 0.94 ( P_trend =0.021) for hemorrhagic stroke, respectively. When we used an updated mean value of HDL cholesterol, the inverse association of HDL cholesterol with stroke risk did not change. This inverse association was consistent among patients of different ages, races, sexes, body mass index, hemoglobin A1c levels, never and past or current smokers, and patients with and without using glucose-lowering, cholesterol-lowering, or antihypertensive agents. Conclusions- The present study found consistent inverse associations between HDL cholesterol and the risk of total, ischemic and hemorrhagic stroke among patients with type 2 diabetes mellitus.

Impact of Cholesterol on Ischemic Stroke in Different Human-Like Hamster Models: A New Animal Model for Ischemic Stroke Study

Rationale: While high low-density lipoprotein cholesterol (LDL-C) and low high-density lipoprotein cholesterol (HDL-C) levels are positively associated with cardiovascular events, it is still unclear whether familial hypercholesterolemia (FH) and Tangier’s disease (TD), caused by mutations in LDLR and ABCA1, respectively, influence ischemic stroke (IS) in humans. Objective: We sought to establish an easier, more effective, and time-saving method to induce IS, then studied the precise effects of different types of lipoproteins on IS. Methods and Results: A new technique termed contralateral middle cerebral artery occlusion (c-MCAO) was introduced to human-like hamster models to induce IS. Compared to traditional distal MCAO (d-MCAO) induced by electrocoagulation, c-MCAO resulted in a more severe IS with larger infarct sizes and more blood–brain barrier (BBB) disruption after 24 h. It was shown that c-MCAO markedly elicited an increase in brain infarct volume and BBB leakage in both homozygous LDLR (LDLR^–/–) and ABCA1 knockout (ABCA1^–/–) hamsters, but not in heterozygous LDLR knockout (LDLR^+/–) hamsters when compared to wild-type (WT) controls. Conclusions: Using human-like genetically engineered hamsters, our findings demonstrated that both high LDL-C level caused by homozygous LDLR deficiency and severe low HDL-C level caused by deleting ABCA1 were risk factors of IS. As such, we believe the development of this novel IS hamster model is suitable for future ischemic/reperfusion studies.

What is the effect of interrupting prolonged sitting with frequent bouts of physical activity or standing on first or recurrent stroke risk factors? A scoping review

The objective of this review was to ascertain the scope of the available literature on the effects of interrupting prolonged sitting time with frequent bouts of physical activity or standing on stroke and recurrent stroke risk factors. Databases Medline, Embase, AMED, CINAHL and Cochrane library were comprehensively searched from inception until 21^st February 2018. Experimental trials which interrupted sitting time with frequent bouts of physical activity or standing in adults (≥ 18 years) were included. Comparison to a bout of prolonged sitting and a measure of at least one first or recurrent stroke risk factor was required to be included. Overall, 30 trials (35 articles) were identified to meet the inclusion criteria. Fifteen trials were completed in participants at an increased risk of having a first stroke and one trial in participants at risk of a recurrent stroke. Outcomes of hypertension and dysglycemia were found to be more favourable following predominately light- to moderate-intensity bouts of physical activity or standing compared to sitting in the majority of trials in participants at risk of having a first stroke. In the one trial of stroke survivors, only outcomes of hypertension were significantly improved. These findings are of significant importance taking into consideration hypertension is the leading risk factor for first and recurrent stroke. However, trials primarily focused on measuring outcomes of dysglycemia and without assessing a dose-response effect. Additional research is required on the dose-response effect of interrupting sitting with frequent bouts of physical activity or standing on first and recurrent stroke risk factors, in those high risk population groups.

Drug Therapy of Dyslipidemia in the Elderly

Abnormal lipoprotein metabolism is an important and modifiable risk factor for atherosclerotic cardiovascular disease (ASCVD), which has been shown in numerous studies to lead to adverse cardiovascular outcomes. As cardiovascular disease (CVD) remains the major cause of morbidity and mortality globally, management of dyslipidemia is a key component of primary and secondary risk-reduction strategies. Because ASCVD risk increases with age, as the population ages, many more people-particularly the elderly-will meet guideline criteria for drug treatment. Statins (HMG-CoA reductase inhibitors) have an unequivocal benefit in reducing ASCVD risk across age groups for secondary prevention. However, the benefit of these drugs for primary prevention in those > 75 years of age remains controversial. We strongly believe that statins should be offered for primary prevention to all older individuals after a shared decision-making process that takes polypharmacy, frailty, and potential adverse effects into consideration. When considering statin therapy in the very old, competing risks of death, and therefore the likelihood that patients will live long enough to benefit from drug therapy, should inform this process. Combination therapies with ezetimibe or proprotein convertase subtilisin-kexin type 9 (PCSK9) inhibitors should be considered to facilitate the use of tolerable doses of statins. Future investigations of dyslipidemia therapies must appropriately include this at-risk population to identify optimal drugs and drug combinations that have a high benefit:risk ratio for the prevention of ASCVD in the elderly.

The impact of monocyte to high-density lipoprotein ratio on reduced renal function: insights from a large population

Aim: To investigate whether monocyte to HDL cholesterol ratio (MHR) can improve the risk stratification of reduced renal function by estimating atherosclerosis. Patients & methods: The cross-sectional study included 8159 subjects (males: 45.73%, mean age: 54.12 years) from Northeast China in 2013. Results: Each standard deviation increase of MHR brought 42.9% additional risk of reduced renal function in males. In females, MHR strongly correlated with reduced renal function before it reached a breakpoint (MHR = 0.25). Additionally, net reclassification improvement identified the value of MHR (0.199; 95% CI: 0.030–0.369; p = 0.021) to improve the risk classification of renal function reduction. Conclusion: This study implicates that MHR is independently associated with reduced renal function and can refine the risk stratification of renal function reduction.

Assessing the performance of monocyte to high-density lipoprotein ratio for predicting ischemic stroke: insights from a population-based Chinese cohort

Background

Monocyte to high-density lipoprotein cholesterol ratio (MHR) is a recently emerged measure of inflammation and oxidative stress and has been used to predict multiple cardiovascular abnormalities, but data relative to ischemic stroke are lacking. The goal of this study was to estimate the associations of MHR and prevalent ischemic stroke among a large cohort of general Chinese population.

Method

The study analyzed 8148 individuals (mean age: 54.1 years; 45.7% males) enrolled in a cross-sectional population-based Northeast China Rural Cardiovascular Health Study (NCRCHS). We identified 194 patients admitted from January and August 2013 with ischemic stroke.

Results

After adjustment for age, sex, and potential confounders, each standard deviation (SD) increment of MHR was predictive to a greater odd of ischemic stroke (odds ratio, 1.276; 95% confidence interval [CI], 1.082–1.504), with subjects in the highest quartile of MHR levels having a 1.6-fold higher risk of prevalent ischemic stroke (95% CI, 1.045–2.524) as compared with those in the lowest quartile. Moreover, smoothing curve showed a linear positive pattern of this association. The area under the curve (AUC) significantly increased (P = 0.042) to 0.808 (95% CI, 0.779–0.837) when the combined MHR was added to the baseline logistic regression model with ischemic stroke risk factors. Also, MHR (0.004) significantly improved integrated discrimination improvement when added to the baseline model.

Conclusions

The present study demonstrated for the first time a linear relation between MHR levels and the odds of ischemic stroke in a large community-based population. The MHR, a marker of high atherosclerotic burden, demonstrated incremental predictive value over traditional clinical risk factors, thus providing clinical utility in risk stratification in subjects presenting with ischemic stroke. These findings had implications for strategies aimed at lowering MHR to prevent adverse cardiovascular and cerebrovascular outcomes.

The Role of High-Density Lipoproteins in Diabetes and Its Vascular Complications

Almost 600 million people are predicted to have diabetes mellitus (DM) by 2035. Diabetic patients suffer from increased rates of microvascular and macrovascular complications, associated with dyslipidaemia, impaired angiogenic responses to ischaemia, accelerated atherosclerosis, and inflammation. Despite recent treatment advances, many diabetic patients remain refractory to current approaches, highlighting the need for alternative agents. There is emerging evidence that high-density lipoproteins (HDL) are able to rescue diabetes-related vascular complications through diverse mechanisms. Such protective functions of HDL, however, can be rendered dysfunctional within the pathological milieu of DM, triggering the development of vascular complications. HDL-modifying therapies remain controversial as many have had limited benefits on cardiovascular risk, although more recent trials are showing promise. This review will discuss the latest data from epidemiological, clinical, and pre-clinical studies demonstrating various roles for HDL in diabetes and its vascular complications that have the potential to facilitate its successful translation.

Association of high-density lipoprotein cholesterol concentration with different types of stroke and coronary heart disease: The Japan Public Health Center-based prospective (JPHC) study

BACKGROUND AND AIMS

Although low high-density lipoprotein (HDL) cholesterol concentration is an established risk factor for coronary heart disease (CHD), information regarding subtypes of stroke is very limited, especially in Asian populations.

METHODS

A prospective study was conducted among 30,736 individuals aged 40-69 years, who lived in nine communities in Japan and did not have a history of cardiovascular disease (CVD). CHD and stroke, including its subtypes, were assessed, and sex-specific hazard ratios (HRs) and 95% confidence intervals (CIs) for outcomes were estimated according to quintiles of HDL cholesterol using Cox proportional models adjusted for other CVD risk factors.

RESULTS

We identified 296 CHD and 1712 stroke events over a median 15 yr of follow-up. HDL cholesterol concentration showed an inverse association with CHD in men and women. A low HDL cholesterol concentration slightly raised the risk for total strokes in men, but not in women. When analyzed by subtypes, we observed an inverse relationship between HDL cholesterol concentration and the incidence of lacunar infarction, with an adjusted HR for the lowest quintile of HDL cholesterol concentration compared with the highest quintile of 1.63 (95% CI, 1.00-2.66) in men and 1.97 (95% CI, 1.19-3.26) in women. HDL cholesterol concentration was positively associated with the risk of intracerebral hemorrhage (ICH) in a linear manner in women (p for trend = 0.028), but not in men.

CONCLUSIONS

The associations of HDL cholesterol concentration with lacunar infarction and ICH may be related to different functional properties of HDL rather than to its protective function against lipid-rich atherosclerosis.

Morinda citrifolia Linn. (Noni) and Its Potential in Obesity-Related Metabolic Dysfunction

Cultural and economic shifts in the early 19th century led to the rapid development of companies that made good profits from technologically-produced commodities. In this way, some habits changed in society, such as the overconsumption of processed and micronutrient-poor foods and devices that gave rise to a sedentary lifestyle. These factors influenced host-microbiome interactions which, in turn, mediated the etiopathogenesis of “new-era” disorders and diseases, which are closely related, such as obesity, type 2 diabetes mellitus, non-alcoholic fatty liver disease, hypertension, and inflammatory bowel disease, which are characterized by chronic dysregulation of metabolic and immune processes. These pathological conditions require novel and effective therapeutic approaches. Morindacitrifolia (noni) is well known as a traditional healing plant due to its medicinal properties. Thus, many studies have been conducted to understand its bioactive compounds and their mechanisms of action. However, in obesity and obesity-related metabolic (dysfunction) syndrome, other studies are necessary to better elucidate noni’s mechanisms of action, mainly due to the complexity of the pathophysiology of obesity and its metabolic dysfunction. In this review, we summarize not only the clinical effects, but also important cell signaling pathways in in vivo and in vitro assays of potent bioactive compounds present in the noni plant which have been reported in studies of obesity and obesity-associated metabolic dysfunction.

Prevalence and Clinical Characteristics of Dyslipidemia in Koreans

The prevalence of hypercholesterolemia in Koreans 30 years old and over was 19.5% in 2015 according to the Korean Nutrition and Health Examination Survey, which means that one-fifth of adults had hypercholesterolemia. The prevalence of hypertriglyceridemia in adults 30 years of age and older was 16.8% in 2015, and men had a 2-fold higher prevalence of hypertriglyceridemia than women (23.9% vs. 10.4%). The awareness of hypercholesterolemia in Koreans was higher in women than among men (62.4% vs. 51.4%). It increased with age; the level of awareness in participants 30 to 49 years of age (32.1% in men and 32.6% in women) was less than half of that observed among respondents ≥65 years old (77.5% in men and 78.0% in women). Regular check-ups for dyslipidemia and the active management thereof are urgent in Korean men aged 30 to 49. In women, the perimenopausal period is crucial for the prevention and management of metabolic syndrome, including dyslipidemia. Overall, improvements in awareness and treatment in the age group of 30 to 49 years in both men and women remain necessary.

The Changing Face of HDL and the Best Way to Measure It

BACKGROUND

HDL cholesterol (HDL-C) is a commonly used lipid biomarker for assessing cardiovascular health. While a central focus has been placed on the role of HDL in the reverse cholesterol transport (RCT) process, our appreciation for the other cardioprotective properties of HDL continues to expand with further investigation into the structure and function of HDL and its specific subfractions. The development of novel assays is empowering the research community to assess different aspects of HDL function, which at some point may evolve into new diagnostic tests.

CONTENT

This review discusses our current understanding of the formation and maturation of HDL particles via RCT, as well as the newly recognized roles of HDL outside RCT. The antioxidative, antiinflammatory, antiapoptotic, antithrombotic, antiinfective, and vasoprotective effects of HDL are all discussed, as are the related methodologies for assessing these different aspects of HDL function. We elaborate on the importance of protein and lipid composition of HDL in health and disease and highlight potential new diagnostic assays based on these parameters.

SUMMARY

Although multiple epidemiologic studies have confirmed that HDL-C is a strong negative risk marker for cardiovascular disease, several clinical and experimental studies have yielded inconsistent results on the direct role of HDL-C as an antiatherogenic factor. As of yet, our increased understanding of HDL biology has not been translated into successful new therapies, but will undoubtedly depend on the development of alternative ways for measuring HDL besides its cholesterol content.