Low High-Density Lipoprotein Cholesterol and High White Blood Cell Counts: A Mendelian Randomization Study

Association Between Monocyte-to-High-Density Lipoprotein Ratio and Prediabetes: A Cross-Sectional Study in Chinese Population

Background

The monocyte-to-high-density lipoprotein cholesterol (MHR) ratio has been linked to metabolic disorders. However, there is limited research on the predisposition to MHR and prediabetes. Hence, we conducted a study to investigate the relationship between MHR and the prevalence of prediabetes.

Methods

In total, 85,293 participants were included in our cross-sectional observational study. Multivariable regression analysis, subgroup analyses, and interaction testing were used to determine the relationship between MHR and prediabetes. To explore the non-linear association of MHR with prediabetes risk, generalized additive model (GAM) and smoothing splines were applied. The threshold effect analysis of MHR on the risk of prediabetes was further employed to identify the turning point.

Results

After controlling for covariates, the results indicated that a positive correlation persisted between MHR and prediabetes (odds ratio (OR) =1.64, 95% confidence interval (CI), 1.48-1.82), and subgroup analyses found a more robust correlation between MHR and prediabetes in individuals with lower age, SBP, DBP, TG, TC and higher values of BMI and LDL-C than in their counterparts. Additionally, the correlation between MHR and the risk of prediabetes was found to be non-linear, with a turning point of -0.4 (Log-Likelihood Ratio, P< 0.001). The impact of variables on the two sides of the turning point were 1.94 (1.72, 2.19) and 0.88 (0.69, 1.14).

Conclusion

The positive correlation between MHR and the risk of prediabetes in Chinese participants was observed to be non-linear, and MHR ≤ -0.4 was strongly positively correlated with prediabetes risk.

Leukocyte ratios in non-diabetic hypertensive Cameroonians do not predict cardiovascular risk : preliminary results of the HYRICCA project

BACKGROUND

Full blood count is routinely performed in the evaluation of hypertensive patients. However, usefulness of leukocyte ratios in cardiovascular risk (CVR) assessment hasn't yet been proven in Cameroonians.

OBJECTIVE

Evaluate the contribution of leukocyte ratios in CVR assessment of non-diabetic hypertensive adults.

METHODOLOGY

We carried out a cross sectional study including non-diabetic hypertensive patients followed up at the cardiology unit of the Yaoundé Central Hospital from November to June 2022. We collected relevant clinical data with a pre-established questionnaire and blood samples from each patient for different biological analyses. The spearman correlation test was used to assess on the one hand the relationship between leukocyte ratios, highly sensitive CRP and the WHO 2019 risk score as our primary end point, and on the other hand between leukocyte indices and the other risk estimators as our secondary outcome. The significant threshold level was set as 0.05.

RESULTS

We included 165 participants (102 females) with a mean age of 57.6 (10.4) years. The median duration of hypertension since diagnosis was 7 years and only 27% of participants on treatment had a controlled blood pressure. There was no significant correlation between leukocyte ratios and the WHO 2019 risk score. Highly sensitive CRP and the atherogenic index of plasma were significantly correlated respectively with the granulocyte to lymphocyte ratio (rho = 0.18, p = 0.03) and the eosinophil to lymphocyte ratio (rho = 0.28, p = 0.01). There exists a weak positive association between the granulocyte to lymphocyte ratio and the Reynolds risk score.

CONCLUSION

Leukocyte ratios are not useful for CVR assessment in hypertensive Cameroonians with respect to the WHO 2019 risk score. Prospective studies are needed to assess their usefulness in combination with conventional risk factors to improve prediction of cardiovascular events.

The mediation effect of HDL-C: Non-HDL-C on the association between inflammatory score and recurrent coronary events

Background

Inflammation and lipids are both involved in the pathogenesis of coronary heart disease (CHD). However, the mediation effect of lipoproteins on the association between inflammation and recurrent coronary events in CHD patients remains unclear.

Methods

This was a retrospective study including CHD patients hospitalized in the Department of Cardiovascular Medicine in Sun Yat-sen Memorial Hospital between January 2011 and December 2012 with the endpoint of recurrent coronary events. The study calculated inflammatory score based on six serum inflammatory markers, including complement C3, complement C4, hyper-sensitive CRP, fibrinogen, D-dimer, and white blood cell count. Logistic regression analysis, subgroup analysis and mediation analysis were performed to assess the associations between inflammatory score and recurrent coronary events in different subpopulations and the identification of mediators. Inflammatory cytokine expression, cholesterol efflux capacity, and hepatic cholesterol influx were performed in additional CHD patients and healthy controls.

Results

There were 191 CHD patients included in the analysis with a median inflammatory score of -0.78 (-2.17, 1.35) and 63 cases of recurrent coronary events. Subgroup logistic regression analysis demonstrated that inflammatory score was positively associated with recurrent coronary events only in the diabetic subgroup [OR: 1.241 (1.004, 1.534), P < 0.046]. HDL-cholesterol (HDL-C): non-HDL-C performed 46.74 % of negative mediation effect on this association. CHD patients had lower cholesterol efflux capacity than healthy controls, which was mediated by HDL: non-HDL ratio of 0.4. No difference was found in hepatic cholesterol influx between the two groups.

Conclusion

Inflammatory score was associated with recurrent coronary events mediated by HDL-C: non-HDL-C ratio in diabetic CHD patients, indicating that lipoproteins might aggravate the inflammatory effect on atherosclerosis under hyperglycemia. Our findings suggested that anti-inflammatory and lipid-lowering therapies might be beneficial for this population.

Evolution of age-related mutation-driven clonal haematopoiesis over 20 years is associated with metabolic dysfunction in obesity

BACKGROUND

Haematopoietic clones caused by somatic mutations with ≥2% variant allele frequency (VAF) increase with age and are linked to risk of haematological malignancies and cardiovascular disease. Recent observations suggest that smaller clones (VAF<2%) are also associated with adverse outcomes. Our aims were to determine the prevalence of clonal haematopoiesis driven by clones of variable sizes in individuals with obesity treated by usual care or bariatric surgery (a treatment that improves metabolic status), and to examine the expansion of clones in relation to age and metabolic dysregulation over up to 20 years.

METHODS

Clonal haematopoiesis-driver mutations (CHDMs) were identified in blood samples from participants of the Swedish Obese Subjects intervention study. Using an ultrasensitive assay, we analysed single-timepoint samples from 1050 individuals treated by usual care and 841 individuals who had undergone bariatric surgery, and multiple-timepoint samples taken over 20 years from a subset (n = 40) of the individuals treated by usual care.

FINDINGS

In this explorative study, prevalence of CHDMs was similar in the single-timepoint usual care and bariatric surgery groups (20.6% and 22.5%, respectively, P = 0.330), with VAF ranging from 0.01% to 31.15%. Clone sizes increased with age in individuals with obesity, but not in those who underwent bariatric surgery. In the multiple-timepoint analysis, VAF increased by on average 7% (range -4% to 24%) per year and rate of clone growth was negatively associated with HDL-cholesterol (R = -0.68, 1.74 E^-04).

INTERPRETATION

Low HDL-C was associated with growth of haematopoietic clones in individuals with obesity treated by usual care.

FUNDING

The Swedish Research Council, The Swedish state under an agreement between the Swedish government and the county councils, the ALF (Avtal om Läkarutbildning och Forskning) agreement, The Swedish Heart-Lung Foundation, The Novo Nordisk Foundation, The European Research Council, The Netherlands Organisation for Scientific Research.

Sterols and immune mechanisms in asthma

The field of sterol and oxysterol biology in lung disease has recently gained attention, revealing a unique need for sterol uptake and metabolism in the lung. The presence of cholesterol transport, biosynthesis, and sterol/oxysterol-mediated signaling in immune cells suggests a role in immune regulation. In support of this idea, statin drugs that inhibit the cholesterol biosynthesis rate-limiting step enzyme, hydroxymethyl glutaryl coenzyme A reductase, show immunomodulatory activity in several models of inflammation. Studies in human asthma reveal contradicting results, whereas promising retrospective studies suggest benefits of statins in severe asthma. Here, we provide a timely review by discussing the role of sterols in immune responses in asthma, analytical tools to evaluate the role of sterols in disease, and potential mechanistic pathways and targets relevant to asthma. Our review reveals the importance of sterols in immune processes and highlights the need for further research to solve critical gaps in the field.

Adjustment of the GRACE Risk Score by Monocyte to High-Density Lipoprotein Ratio Improves Prediction of Adverse Cardiovascular Outcomes in Patients With Acute Coronary Syndrome Undergoing Percutaneous Coronary Intervention

Background and Aims

The monocyte to high-density lipoprotein cholesterol ratio (MHR), a novel marker for inflammation and lipid metabolism, has been demonstrated to be associated with poor prognosis in many patient populations. However, the prognostic influence of MHR in patients with acute coronary syndrome (ACS) undergoing percutaneous coronary intervention (PCI) is poorly understood. Here, we sought to investigate the relationship between MHR and adverse cardiovascular (CV) outcomes in such patients and determine whether MHR could improve the GRACE risk score based prognostic models.

Methods and Results

MHR was applied to 1,720 patients with ACS undergoing PCI who were admitted to our CV center from June 2016 to November 2017. These patients were stratified into three groups according to MHR tertiles. The relationship between MHR and the primary endpoint (overall death, non-fatal stroke, non-fatal myocardial infarction, or unplanned repeat revascularization) was examined by Cox proportional hazards regression analysis. During a median follow-up of 31 months, 353 patients had at least one primary endpoint event. Compared with those in the lowest MHR tertile, patients in the middle and highest tertiles [adjusted HR: 1.541 (95% CI: 1.152–2.060) and 1.800 (95%CI: 1.333–2.432), respectively], had a higher risk of the primary endpoint. The addition of MHR has an incremental effect on the predictive ability of the GRACE risk score for the primary endpoint (cNRI: 0.136, P < 0.001; IDI: 0.006, P < 0.001).

Conclusion

MHR was independently and significantly associated with adverse CV outcomes in ACS patients who underwent PCI and improved the predictive ability of the GRACE risk score based prognostic models.

Registration Number

http://www.chictr.org.cn/hvshowproject.aspx?id=21397; ChiCTR1800017417.

Clonal hematopoiesis in cardiovascular disease and therapeutic implications

Clonal hematopoiesis arises from somatic mutations that provide a fitness advantage to hematopoietic stem cells and the outgrowth of clones of blood cells. Clonal hematopoiesis commonly involves mutations in genes that are involved in epigenetic modifications, signaling and DNA damage repair. Clonal hematopoiesis has emerged as a major independent risk factor in atherosclerotic cardiovascular disease, thrombosis and heart failure. Studies in mouse models of clonal hematopoiesis have shown an increase in atherosclerosis, thrombosis and heart failure, involving increased myeloid cell inflammatory responses and inflammasome activation. Although increased inflammatory responses have emerged as a common underlying principle, some recent studies indicate mutation-specific effects. The discovery of the association of clonal hematopoiesis with cardiovascular disease and the recent demonstration of benefit of anti-inflammatory treatments in human cardiovascular disease converge to suggest that anti-inflammatory treatments should be directed to individuals with clonal hematopoiesis. Such treatments could target specific inflammasomes, common downstream mediators such as IL-1β and IL-6, or mutations linked to clonal hematopoiesis.

Addressing dyslipidemic risk beyond LDL-cholesterol

Despite the success of LDL-lowering drugs in reducing cardiovascular disease (CVD), there remains a large burden of residual disease due in part to persistent dyslipidemia characterized by elevated levels of triglyceride-rich lipoproteins (TRLs) and reduced levels of HDL. This form of dyslipidemia is increasing globally as a result of the rising prevalence of obesity and metabolic syndrome. Accumulating evidence suggests that impaired hepatic clearance of cholesterol-rich TRL remnants leads to their accumulation in arteries, promoting foam cell formation and inflammation. Low levels of HDL may associate with reduced cholesterol efflux from foam cells, aggravating atherosclerosis. While fibrates and fish oils reduce TRL, they have not been uniformly successful in reducing CVD, and there is a large unmet need for new approaches to reduce remnants and CVD. Rare genetic variants that lower triglyceride levels via activation of lipolysis and associate with reduced CVD suggest new approaches to treating dyslipidemia. Apolipoprotein C3 (APOC3) and angiopoietin-like 3 (ANGPTL3) have emerged as targets for inhibition by antibody, antisense, or RNAi approaches. Inhibition of either molecule lowers TRL but respectively raises or lowers HDL levels. Large clinical trials of such agents in patients with high CVD risk and elevated levels of TRL will be required to demonstrate efficacy of these approaches.

Clinical Predictors of High Blood Eosinophils in Chronic Obstructive Pulmonary Disease

Purpose

Elevated blood eosinophils have been implicated in chronic obstructive pulmonary disease (COPD) progression and exacerbation. We aim to investigate clinical predictors of high blood eosinophils in a Chinese COPD cohort.

Patients and Methods

We conducted a retrospective cohort study in Sichuan province, a Southwest province with high prevalence of COPD in China. All patients in this cohort were extracted from the Chinese Pulmonary Health study, a large cross-sectional study on COPD epidemiology in China. Demographics, personal and family history, living condition, spirometry and blood eosinophil counts were obtained. Univariate and multiple linear regression analyses were performed to determine predictors of high blood eosinophils.

Results

A total of 375 COPD patients were included in this cohort. The median absolute blood eosinophil count was 138.8 cells/μL, and the prevalence of COPD with high blood eosinophils was 66.7% and 14.7% when using the thresholds of 100 cells/μL and 300 cells/μL, respectively. Univariate analyses indicated that male gender, lower body mass index, high-density lipoprotein (HDL), lower family income, raising pets and biomass use were significantly associated with high blood eosinophils (p < 0.05). Multiple linear regression model further revealed male gender (unstandardized coefficient (B)=66.125, 95% confidence intervals (CI) 16.350 to 115.900, p=0.009), age (B=2.819, 95% CI 0.639 to 5.000, p=0.012) predicted high blood eosinophil level, whereas HDL (B=−64.682, 95% CI −123.451 to −5.914, p=0.031) was a negative predictor for high blood eosinophils.

Conclusion

This retrospective cohort study suggests male gender, oldness and lower HDL could be clinical predictors of high blood eosinophils in Chinese COPD patients.

Association between Polygenetic Risk Scores of Low Immunity and Interactions between These Scores and Moderate Fat Intake in a Large Cohort

White blood cell (WBC) counts represent overall immunity. However, a few studies have been conducted to explore the genetic impacts of immunity and their interaction with lifestyles. We aimed to identify genetic variants associated with a low-WBC risk and document interactions between polygenetic risk scores (PRS), lifestyle factors, and nutrient intakes that influence low-WBC risk in a large hospital-based cohort. Single nucleotide polymorphisms (SNPs) were selected by genome-wide association study of participants with a low-WBC count (<4 × 10⁹/L, n = 4176; low-WBC group) or with a normal WBC count (≥4 × 10⁹/L, n = 36,551; control group). The best model for gene-gene interactions was selected by generalized multifactor dimensionality reduction. PRS was generated by summing selected SNP risk alleles of the best genetic model. Adjusted odds ratio (ORs) of the low-WBC group were 1.467 (1.219–1.765) for cancer incidence risk and 0.458 (0.385–0.545) for metabolic syndrome risk. Vitamin D intake, plant-based diet, and regular exercise were positively related to the low-WBC group, but smoking and alcohol intake showed an inverse association. The 7 SNPs included in the best genetic model were PSMD3_rs9898547, LCT_rs80157389, HLA-DRB1_rs532162239 and rs3097649, HLA-C rs2308575, CDKN1A_rs3176337 and THRA_rs7502539. PRS with 7 SNP model were positively associated with the low-WBC risk by 2.123-fold (1.741 to 2.589). PRS interacted with fat intake and regular exercise but not with other nutrient intakes or lifestyles. The proportion with the low WBC in the participants with high-PRS was lower among those with moderate-fat intake and regular exercise than those with low-fat intake and no exercise. In conclusion, adults with high-PRS had a higher risk of a low WBC count, and they needed to be advised to have moderate fat intake (20–25 energy percent) and regular exercise.

HDL in Immune-Inflammatory Responses: Implications beyond Cardiovascular Diseases

High density lipoproteins (HDL) are heterogeneous particles composed by a vast array of proteins and lipids, mostly recognized for their cardiovascular (CV) protective effects. However, evidences from basic to clinical research have contributed to depict a role of HDL in the modulation of immune-inflammatory response thus paving the road to investigate their involvement in other diseases beyond those related to the CV system. HDL-C levels and HDL composition are indeed altered in patients with autoimmune diseases and usually associated to disease severity. At molecular levels, HDL have been shown to modulate the anti-inflammatory potential of endothelial cells and, by controlling the amount of cellular cholesterol, to interfere with the signaling through plasma membrane lipid rafts in immune cells. These findings, coupled to observations acquired from subjects carrying mutations in genes related to HDL system, have helped to elucidate the contribution of HDL beyond cholesterol efflux thus posing HDL-based therapies as a compelling interventional approach to limit the inflammatory burden of immune-inflammatory diseases.