A genome-wide association study on lipoprotein (a) levels and coronary artery disease severity in a Chinese population

Novel metabolic and inflammatory stratification of overweight/obesity to characterize risks of adverse outcomes: A large population-based cohort study

AIMS

The growing epidemic of overweight and obesity elevates disease risks, with metabolic disorders and inflammation critically involved in the pathogenic mechanisms. This study refines the subtyping of overweight and obesity using metabolic and inflammatory markers to enhance risk assessment and personalized prevention.

MATERIALS AND METHODS

Based on the UK Biobank, this retrospective study included participants classified as overweight or obese (BMI ≥25 kg/m2). K-means clustering was performed using metabolic and inflammatory biomarkers. Multivariate Cox regression analysis assessed the risk of complications and mortality over a follow-up period of 13.5 years. Genome-Wide Association Studies (GWAS) and Phenome-Wide Association Studies (PheWAS) explored cluster-specific genetic traits.

RESULTS

Among 126 145 participants (mean [IQR] age: 55.0 [14.0] years; 61 983 males [49.1%]), five clusters were identified: (1) Low Metabolic Risk-related, (2) Hypertension-Related, (3) Mixed Hyperlipidemia-Related, (4) Elevated Lipoprotein(a)-Related and (5) High BMI and Inflammation-Related. Cluster 1 exhibited a lower risk of complications than other clusters. Cluster 2 had the highest incidence of stroke, linked to variants affecting blood circulation. Cluster 3 showed the highest risks for ischaemic heart disease, characterized by variants enriched in cholesterol metabolism pathways. Cluster 4 was associated with high cardiovascular risks. Cluster 5 had the highest risks for diabetes, asthma, chronic obstructive pulmonary disease, osteoarthritis and mortality, linked to obesity-related genetic variants. We also proposed a method for applying this classification in clinical settings.

CONCLUSIONS

This classification provides insights into the heterogeneity of individuals with overweight and obesity, aiding in the identification of high-risk patients who may benefit from targeted interventions.

Lipoprotein(a) molar concentrations rather than genetic variants better predict coronary artery disease risk and severity in Han Chinese population

BACKGROUND

It is well established that increased lipoprotein(a) [Lp(a)] is a significant risk factor for coronary artery disease (CAD). Plasma Lp(a) levels are genetically determined and vary widely between different races, regions and individuals. However, most studies on Lp(a) associated genetic variants have focused on the Caucasian population currently. Our study aimed to test the associations among LPA genetic variants, Lp(a) concentrations, and CAD in a Han Chinese cohort.

METHODS

A total of 3779 patients undergoing coronary angiography were recruited from Tongji Hospital. LPA Kringle IV type 2 (KIV-2) copies were detected using TaqMan probe real-time quantitative polymerase chain reaction (qPCR) analysis and fifteen single nucleotide polymorphisms (SNPs) within the LPA gene were detected using TaqMan probe genotyping analysis. LPA genetic risk score (GRS) was computed based on seven SNPs associated with Lp(a). Associations of LPA genetic variants with Lp(a) and CAD were evaluated using linear regression analyses and Logistic regression analyses, respectively.

RESULTS

Compared with the first quartile of Lp(a), the fourth quartile exhibited a significant association with CAD [odds ratio (OR): 2.08, 95% confidence interval (CI): 1.67-2.59, p < 0.001], multivessel CAD [OR: 2.54, 95% CI: 2.06-3.12, p < 0.001], and high Gensini scores [OR: 2.17, 95% CI: 1.77-2.66, p < 0.001] after multivariable adjustment for cardiovascular risk factors. Both LPA GRS and KIV-2 quartiles were associated with Lp(a) concentrations (both p for trend < 0.001). However, after false discovery rate (FDR) correction, there were no significant associations of LPA genetic variants with CAD, multivessel CAD or high Gensini scores.

CONCLUSIONS

Our findings indicate LPA genetic variants can affect Lp(a) levels, but do not exceed Lp(a) molar concentrations to predict CAD incidence and severity usefully, highlighting the importance of Lp(a) detection and management.

Lipoprotein(a) as an Independent Predictor of Elevated SYNTAX Score

Background/Objectives: Increased lipoprotein(a) [Lp(a)] level is associated with elevated possibility of atherosclerosis progression. SYNTAX score enables to grade the anatomy of coronary arteries. To identify the impact of increased Lp(a) level on SYNTAX score in individuals with acute myocardial infarction (AMI). Methods: In our analysis, we enrolled 173 consecutive adult patients hospitalized for AMI in a tertiary cardiology center from December 2022 to August 2023. Patient characteristics were compared for patients with SYNTAX score ≥ 23 (64 patients) and SYNTAX score < 23 (109 patients). The SYNTAX score was estimated based on the results of coronary angiography. Logistic regression analyses were performed to evaluate the factors associated with SYNTAX score. Results: Individuals with the SYNTAX score ≥ 23 were more likely to have arterial hypertension, diabetes mellitus, significant stenosis in the left main coronary artery, and higher Lp(a) levels than those with SYNTAX < 23 (all p < 0.05). On univariate analysis, age (OR 1.05, 95% CI 1.02-1.08, p = 0.001), Lp(a) levels (OR 1.04, 95% CI 1.01-1.06, p = 0.001), and arterial hypertension (OR 2.69, 95% CI 1.26-5.74, p = 0.011) were associated with SYNTAX score ≥ 23. Multivariable determinants of SYNTAX score ≥ 23 were as follows: Lp(a) levels (OR 1.03, 95% CI 1.01-1.08, p = 0.029), and age (OR 1.04, 95% CI 1.01-1.07, p = 0.005). The cut-off value for Lp(a) 166.16 nmol/L identifies patients with SYNTAX score ≥ 23 with 97% sensitivity and 44% specificity (area under curve 0.78, p < 0.001). Conclusions: Elevated Lp(a) concentration is associated with a higher SYNTAX score. A cut-off value of Lp(a) above 166.16 nmol/L allows us to identify subjects with SYNTAX score ≥ 23 with good specificity and sensitivity.

Mitochondrial related variants associated with cardiovascular traits

Introduction

Cardiovascular disease (CVD) is responsible for over 30% of mortality worldwide. CVD arises from the complex influence of molecular, clinical, social, and environmental factors. Despite the growing number of autosomal genetic variants contributing to CVD, the cause of most CVDs is still unclear. Mitochondria are crucial in the pathophysiology, development and progression of CVDs; the impact of mitochondrial DNA (mtDNA) variants and mitochondrial haplogroups in the context of CVD has recently been highlighted.

Aims

We investigated the role of genetic variants in both mtDNA and nuclear-encoded mitochondrial genes (NEMG) in CVD, including coronary artery disease (CAD), hypertension, and serum lipids in the UK Biobank, with sub-group analysis for diabetes.

Methods

We investigated 371,542 variants in 2,527 NEMG, along with 192 variants in 32 mitochondrial genes in 381,994 participants of the UK Biobank, stratifying by presence of diabetes.

Results

Mitochondrial variants showed associations with CVD, hypertension, and serum lipids. Mitochondrial haplogroup J was associated with CAD and serum lipids, whereas mitochondrial haplogroups T and U were associated with CVD. Among NEMG, variants within Nitric Oxide Synthase 3 (NOS3) showed associations with CVD, CAD, hypertension, as well as diastolic and systolic blood pressure. We also identified Translocase Of Outer Mitochondrial Membrane 40 (TOMM40) variants associated with CAD; Solute carrier family 22 member 2 (SLC22A2) variants associated with CAD and CVD; and HLA-DQA1 variants associated with hypertension. Variants within these three genes were also associated with serum lipids.

Conclusion

Our study demonstrates the relevance of mitochondrial related variants in the context of CVD. We have linked mitochondrial haplogroup U to CVD, confirmed association of mitochondrial haplogroups J and T with CVD and proposed new markers of hypertension and serum lipids in the context of diabetes. We have also evidenced connections between the etiological pathways underlying CVDs, blood pressure and serum lipids, placing NOS3, SLC22A2, TOMM40 and HLA-DQA1 genes as common nexuses.

A Polynesian-specific SLC22A3 variant associates with low plasma lipoprotein(a) concentrations independent of apo(a) isoform size in males

Lipoprotein(a) (Lp(a)) is a low-density lipoprotein (LDL)-like particle in which the apolipoprotein B component is covalently linked to apolipoprotein(a) (apo(a)). Lp(a) is a well-established independent risk factor for cardiovascular diseases. Plasma Lp(a) concentrations vary enormously between individuals and ethnic groups. Several nucleotide polymorphisms in the SLC22A3 gene associate with Lp(a) concentration in people of different ethnicities. We investigated the association of a Polynesian-specific (Māori and Pacific peoples) SLC22A3 gene coding variant p.Thr44Met) with the plasma concentration of Lp(a) in a cohort of 302 healthy Polynesian males. An apo(a)-size independent assay assessed plasma Lp(a) concentrations; all other lipid and apolipoprotein concentrations were measured using standard laboratory techniques. Quantitative real-time polymerase chain reaction was used to determine apo(a) isoforms. The range of metabolic (HbA1c, blood pressure, and blood lipids) and blood lipid variables were similar between the non-carriers and carriers in age, ethnicity and BMI adjusted models. However, rs8187715 SLC22A3 variant was significantly associated with lower Lp(a) concentrations. Median Lp(a) concentration was 10.60 nmol/L (IQR: 5.40-41.00) in non-carrier group, and was 7.60 nmol/L (IQR: 5.50-12.10) in variant carrier group (P<0.05). Lp(a) concentration inversely correlated with apo(a) isoform size. After correction for apo(a) isoform size, metabolic parameters and ethnicity, the association between the SLC22A3 variant and plasma Lp(a) concentration remained. The present study is the first to identify the association of this gene variant and low plasma Lp(a) concentrations. This provides evidence for better guidance on ethnic specific cut-offs when defining 'elevated' and 'normal' plasma Lp(a) concentrations in clinical applications.

Non-Random Enrichment of Single-Nucleotide Polymorphisms Associated with Clopidogrel Resistance within Risk Loci Linked to the Severity of Underlying Cardiovascular Diseases: The Role of Admixture

Cardiovascular disease (CVD) is one of the leading causes of death in Puerto Rico, where clopidogrel is commonly prescribed to prevent ischemic events. Genetic contributors to both a poor clopidogrel response and the severity of CVD have been identified mainly in Europeans. However, the non-random enrichment of single-nucleotide polymorphisms (SNPs) associated with clopidogrel resistance within risk loci linked to underlying CVDs, and the role of admixture, have yet to be tested. This study aimed to assess the possible interaction between genetic biomarkers linked to CVDs and those associated with clopidogrel resistance among admixed Caribbean Hispanics. We identified 50 SNPs significantly associated with CVDs in previous genome-wide association studies (GWASs). These SNPs were combined with another ten SNPs related to clopidogrel resistance in Caribbean Hispanics. We developed Python scripts to determine whether SNPs related to CVDs are in close proximity to those associated with the clopidogrel response. The average and individual local ancestry (LAI) within each locus were inferred, and 60 random SNPs with their corresponding LAIs were generated for enrichment estimation purposes. Our results showed no CVD-linked SNPs in close proximity to those associated with the clopidogrel response among Caribbean Hispanics. Consequently, no genetic loci with a dual predictive role for the risk of CVD severity and clopidogrel resistance were found in this population. Native American ancestry was the most enriched within the risk loci linked to CVDs in this population. The non-random enrichment of disease susceptibility loci with drug-response SNPs is a new frontier in Precision Medicine that needs further attention.

Exploring the role of lipoprotein(a) in cardiovascular diseases and diabetes in Chinese population

A high level of lipoprotein (a) in the plasma has been associated with a variety of cardiovascular diseases and is considered to be an independent predictor of some other diseases. Based on recent studies, the concentration levels of Lp(a) in the Chinese population exhibit a distinctive variation from other populations. In the Chinese population, a high level of Lp(a) indicates a higher incidence of revascularization, platelet aggregation, and thrombogenicity following PCI. Increased risk of atherosclerotic cardiovascular disease (ASCVD) in Chinese population has been linked to higher levels of Lp(a), according to studies. More specifically, it has been found that in Chinese populations, higher levels of Lp(a) were linked to an increased risk of coronary heart disease, severe aortic valve stenosis, deep vein thrombosis in patients with spinal cord injuries, central vein thrombosis in patients receiving hemodialysis, and stroke. Furthermore, new and consistent data retrieved from several clinical trials also suggest that Lp (a) might also play an essential role in some other conditions, including metabolic syndrome, type 2 diabetes and cancers. This review explores the clinical and epidemiological relationships among Lp(a), cardiovascular diseases and diabetes in the Chinese population as well as potential Lp(a) underlying mechanisms in these diseases. However, further research is needed to better understand the role of Lp(a) in cardiovascular diseases and especially diabetes in the Chinese population.

Association of lipoprotein(a) with coronary severity in patients with new-onset acute myocardial infarction: A large cross-sectional study

BACKGROUND

Although current evidence suggests a causal association between lipoprotein(a) [Lp(a)] and cardiovascular disease, there is still no consensus on its association with coronary severity in new-onset acute myocardial infarction (AMI). We explored the association of Lp(a) with coronary severity.

METHODS

In this large cross-sectional study, we enrolled 2,740 patients with new-onset AMI from the Zhongda Hospital affiliated to Southeast University. Lp(a) was considered as an exposure variable. Gensini score, left main disease and three-vessel disease were used to assess coronary severity. Multivariate logistic regression, restricted cubic spline (RCS) models and threshold effects were used to analyze the association of Lp(a) with coronary severity.

RESULTS

Multivariate adjusted models showed that Lp(a) was independently associated with Gensini score (≥100), left main disease and three-vessel disease [Q4 vs Q1, OR (95 % CI), P value: 2.301 (1.770, 2.992), P < 0.001; 1.743 (1.174, 2.587), P = 0.006; 1.431 (1.128, 1.816), P = 0.003; respectively], and the associations persisted in sensitivity analyses and most subgroups (P < 0.05). Additionally, the RCS showed that Lp(a) was nonlinearly associated with Gensini score (continuous variable), Gensini score (≥100) and three-vessel disease (P for nonlinearity < 0.05). Threshold effects analysis showed that Lp(a) above the inflection point was positively associated with Gensini score (continuous variable) as well as the risk of Gensini score (≥100) and three-vessel disease.

CONCLUSION

Lp(a) was closely associated with coronary severity represented by Gensini score, left main disease and three-vessel disease in patients with new-onset AMI.

Predictive effect of different blood lipid parameters combined with carotid intima-media thickness on coronary artery disease

Background

Blood lipids disorder and atherosclerosis are closely related to coronary artery disease (CAD). This study aims to compare different blood lipid parameters combined with carotid intima-media thickness (cIMT) in predicting CAD.

Methods

This was a retrospective study including patients who underwent coronary angiography for highly suspected CAD. Blood samples were taken for lipid profile analysis and cIMT was evaluated by carotid ultrasound. Logistic analysis was used to establish different models of different lipid parameters in predicting CAD. The area under the receiver operating characteristic curve (AUC) was used to examine the predictive value. The optimal lipid parameter was also used to explore the relationship with multi-vessel CAD.

Results

Patients were classified into two groups based on whether CAD existed. Compared with non-CAD patients, the CAD group had higher lipoprotein (a) [Lp (a)], apolipoprotein B/apolipoprotein A, total cholesterol/high-density lipoprotein cholesterol (HDL-C), triglyceride/HDL-C and LDL-C/HDL-C. According to the AUCs, Lp (a) combined with cIMT (AUC: 0.713, P < 0.001) had the best performance in predicting CAD compared to other lipid parameters. High level of Lp (a) was also associated with multi-vessel CAD (odds ratio: 1.41, 95% confidence interval: 1.02-1.95, P = 0.036).

Conclusion

For patients with highly suspected CAD, Lp (a) better improved the predictive value of CAD rather than most of blood lipid indices, especially in the absence of high levels of LDL-C. Lp (a) also can be used to predict the multi-vessel CAD.

Lipoprotein(a) and Cardiovascular Disease in Chinese Population: A Beijing Heart Society Expert Scientific Statement

Elevated concentration of lipoprotein(a) [Lp(a)] is an independent risk factor for atherosclerotic cardiovascular disease, including coronary artery disease, stroke, peripheral artery disease, and so on. Emerging data suggest that Lp(a) contributes to the increased risk for cardiovascular events even in the setting of effective reduction of plasma low-density lipoprotein cholesterol. Nevertheless, puzzling issues exist covering potential genetic factors, Lp(a) assay, possible individuals for analysis, a cutoff point of increased risk, and clinical interventions. In the Chinese population, Lp(a) exhibited a distinctive prevalence and regulated various cardiovascular diseases in specific ways. Hence, it is valuable to clarify the role of Lp(a) in cardiovascular diseases and explore prevention and control measures for the increase in Lp(a) prevalence in the Chinese population. This Beijing Heart Society experts' scientific statement will present the detailed knowledge concerning Lp(a)-related studies combined with Chinese population observations to provide the key points of reference.

The Inherited Hypercholesterolemias

Inherited hypercholesterolemias include monogenic and polygenic disorders, which can be very rare (eg, cerebrotendinous xanthomatosis (CTX)) or relatively common (eg, familial combined hyperlipidemia [FCH]). In this review, we discuss familial hypercholesterolemia (FH), FH-mimics (eg, polygenic hypercholesterolemia [PH], FCH, sitosterolemia), and other inherited forms of hypercholesterolemia (eg, hyper-lipoprotein(a) levels [hyper-Lp(a)]). The prevalence, genetics, and management of inherited hypercholesterolemias are described and selected guidelines summarized.

Elevated serum lipoprotein(a) is significantly associated with angiographic progression of coronary artery disease

Background

Lipoprotein(a)[Lp(a)] has been considered as an independent risk factor for coronary artery disease (CAD). The present study aimed to evaluate the association between baseline serum Lp(a) and CAD progression determined by angiographic score.

Methods

A total of 814 patients who had undergone two or more coronary computed tomography angiography at least 6 months apart were consecutively enrolled and the coronary severity was determined by the Gensini score system. Patients were stratified into two groups according to Lp(a)>300 mg/L and Lp(a) ≤ 300 mg/L or classified as “progressors” and “non‐progressors” based on the Gensini score rate of change per year. The association of continuous Lp(a) and Lp(a)>300 mg/L with CAD progression were respectively assessed by logistic regression analysis. Moreover, further evaluation of those association was performed in subgroups of the study population.

Results

Patients in the “progressors” group had significant higher Lp(a) levels. Furthermore, the multivariate logistic regression analysis showed that elevated Lp(a) (odds ratio [OR]: 1.451, 95% confidence interval [CI]: 1.177–1.789, p<.001) and Lp(a)>300 mg/L (OR:1.642, 95% CI:1.018–2.649, p = .042) were positively associated with CAD progression after adjusting for confounding factors. In addition, those relation seemed to be more prominent in subjects with lower body mass index (OR: 1.880, 95% CI: 1.224–2.888, p for interaction = .060).

Conclusions

Elevated baseline serum Lp(a) is positively and independently associated with angiographic progression of CAD, particularly in participants with relatively low body mass index. Therefore, Lp(a) could be a potent risk factor for CAD progression, assisting in early risk stratification in cardiovascular patients.

Associations of Mitochondrial Variants With Lipidomic Traits in a Chinese Cohort With Coronary Artery Disease

Plasma lipids have been at the center stage of the prediction and prevention strategies for cardiovascular diseases (CVDs), and novel lipidomic traits have been recognized as reliable biomarkers for CVD risk prediction. The mitochondria serve as energy supply sites for cells and can synthesize a variety of lipids autonomously. Therefore, investigating the relationships between mitochondrial single nucleotide polymorphism (SNPs) and plasma lipidomic traits is meaningful. Here, we enrolled a total of 1,409 Han Chinese patients with coronary artery disease from three centers and performed linear regression analyses on the SNPs of mitochondrial DNA (mtDNA) and lipidomic traits in two independent groups. Sex, age, aspartate aminotransferase, estimated glomerular filtration rate, antihypertensive drugs, hypertension, and diabetes were adjusted. We identified three associations, namely, D-loop_m.16089T>C with TG(50:4) NL-16:0, D-loop_m.16145G>A with TG(54:5) NL-18:0, and D-loop_m.16089T>C with PC(16:0_16:1) at the statistically significant threshold of FDR < 0.05. Then, we explored the relationships between mitochondrial genetic variants and traditional lipids, including triglyceride, total cholesterol (TC), low-density lipoprotein cholesterol (LDLC), and high-density lipoprotein cholesterol. Two significant associations were found, namely MT-ND6_m.14178T>C with TC and D-loop_m.215A>G with LDLC. Furthermore, we performed linear regression analysis to determine on the SNPs of mtDNA and left ventricular ejection fraction (LVEF) and found that the SNP D-loop_m.16145G>A was nominally significantly associated with LVEF (P = 0.047). Our findings provide insights into the lipidomic context of mtDNA variations and highlight the importance of studying mitochondrial genetic variants related to lipid species.

Genome-Wide Association Study Highlights APOH as a Novel Locus for Lipoprotein(a) Levels-Brief Report

OBJECTIVE

Lp(a) (lipoprotein[a]) is an independent risk factor for cardiovascular diseases and plasma levels are primarily determined by variation at the LPA locus. We performed a genome-wide association study in the UK Biobank to determine whether additional loci influence Lp(a) levels. Approach and Results: We included 293 274 White British individuals in the discovery analysis. Approximately 93 095 623 variants were tested for association with natural log-transformed Lp(a) levels using linear regression models adjusted for age, sex, genotype batch, and 20 principal components of genetic ancestry. After quality control, 131 independent variants were associated at genome-wide significance (P≤5×10-8). In addition to validating previous associations at LPA, APOE, and CETP, we identified a novel variant at the APOH locus, encoding β2GPI (beta2-glycoprotein I). The APOH variant rs8178824 was associated with increased Lp(a) levels (β [95% CI] [ln nmol/L], 0.064 [0.047-0.081]; P=2.8×10-13) and demonstrated a stronger effect after adjustment for variation at the LPA locus (β [95% CI] [ln nmol/L], 0.089 [0.076-0.10]; P=3.8×10-42). This association was replicated in a meta-analysis of 5465 European-ancestry individuals from the Framingham Offspring Study and Multi-Ethnic Study of Atherosclerosis (β [95% CI] [ln mg/dL], 0.16 [0.044-0.28]; P=0.0071).

CONCLUSIONS

In a large-scale genome-wide association study of Lp(a) levels, we identified APOH as a novel locus for Lp(a) in individuals of European ancestry. Additional studies are needed to determine the precise role of β2GPI in influencing Lp(a) levels as well as its potential as a therapeutic target.

The Evolving Understanding and Approach to Residual Cardiovascular Risk Management

Despite unprecedented advances in treatment of atherosclerotic cardiovascular disease, it remains the leading cause of death and disability worldwide. Treatment of major traditional risk factors, including low-density lipoprotein-cholesterol, serves as the foundation of atherosclerotic risk reduction. However, there remains a significant residual risk of cardiovascular events despite optimal risk factor management. Beyond traditional risk factors, other drivers of residual risk have come to the forefront, including inflammatory, pro-thrombotic, and metabolic pathways that contribute to recurrent events and are often unrecognized and not addressed in clinical practice. This review will explore the evidence linking these pathways to atherosclerotic cardiovascular disease and potential future therapeutic options to attenuate residual cardiovascular risk conferred by these pathways.

The Association of Syntax Score with Levels of Lipoprotein(a) and Inflammatory Biomarkers in Patients with Stable Coronary Artery Disease and Different Low-Density Lipoprotein Cholesterol Levels

INTRODUCTION

Lipoprotein(a) (Lp(a)) is associated with the severity of coronary lesions evaluated using Syntax score in patients with stable coronary artery disease (CAD). However, the effect of low-density lipoprotein cholesterol (LDL-C) levels on the association of Lp(a) levels with Syntax score remains unclear.

METHODS

A total of 646 patients with stable CAD were enrolled in the present study. Lp(a) levels were measured with an AU5800 Chemistry Analyzer. Syntax scores were calculated by two advanced interventional cardiologists. SPSS 22.0 was used for statistical analyses.

RESULTS

The concentration of Lp(a) ranged from 1 to 192 mg/dL. Pearson's correlation analysis showed a positive correlation between Syntax score and the level of Lp(a) (r = 0.108, p = 0.006). The LDL-C ≥100 mg/dL group presented with a higher Lp(a) level, 16 (9-29) vs 13 (7-24). Pearson's correlation analysis identified a correlation between Lp(a) level and Syntax score (r = 0.249, p < 0.001) only in the LDL-C ≥100 mg/dL group. Multivariate logistic regression analysis revealed the positive predictive value of an Lp(a) level >30 mg/dL for a Syntax score ≥23 only in the LDL-C ≥100 mg/dL group, adjusted odds ratio 2.895, p = 0.010. A receiver operating characteristic curve analysis confirmed the predictive value of Lp(a) levels for a Syntax score ≥23 in the LDL-C ≥100 mg/dL group with a cutoff value for Lp(a) >30 mg/dL.

DISCUSSION

The association between Lp(a) level and Syntax score was only maintained in the LDL-C ≥100 mg/dL group. An Lp(a) level >30 mg/dL was an independent predictor of a Syntax score ≥23 only in the LDL-C ≥100 mg/dL group. The effect of LDL-C levels on the association of Lp(a) levels with Syntax score requires further investigations.

Association of SGK1 Polymorphisms With Susceptibility to Coronary Heart Disease in Chinese Han Patients With Comorbid Depression

There is a strong link between heart disease and depression, both of which are closely related to lifetime stress exposure. Serum/glucocorticoid-regulated kinase 1 (SGK1) is a stress-responsive gene with a pivotal role in both the heart and brain. To determine the role of SGK1 polymorphisms (rs2758151, rs1743963, rs9493857, rs1763509, rs9376026, and rs9389154) in susceptibility to comorbid coronary heart disease (CHD) and depression, we conducted a hospital-based case–control study involving 257 CHD cases (including 69 cases with depression and 188 cases without depression) and 107 controls in a Chinese Han population. Six single-nucleotide polymorphisms (SNPs) in the SGK1 gene were successfully genotyped by polymerase chain reaction–ligase detection reaction (PCR-LDR) assay. Our results showed no significant differences in SGK1 genetic polymorphisms between CHD patients and controls, whereas significant associations were observed between SGK1 SNPs (rs1743963 and rs1763509) and the development of depression in CHD patients (P = 0.018 by genotype, P = 0.032 by allele; P = 0.017 by genotype, P = 0.003 by allele, respectively). However, none of these associations remained significant after Bonferroni correction (P = 0.054 for rs1743963; P = 0.051 for rs1763509). Interestingly, both the GG genotype of SGK1 rs1743963 and AA genotype of SGK1 rs1763509 were associated with a higher risk of depression in CHD patients; for rs1763509, the Patient Health Questionnaire-9 (PHQ-9) scores in the carriers of the risk genotype for comorbid depression, AA, were significantly higher than in GG and AG carriers (P = 0.008). Notably, haplotype analysis indicated that haplotype GGA significantly increased the risk of depression in CHD patients (P = 0.011, odds ratio (OR) = 1.717, 95% confidence interval (CI) = 1.132–2.605), whereas haplotype AAG may be a protective factor for CHD patients with comorbid depression (P = 0.038, OR = 0.546, 95% CI = 0.307–0.972). It should be noted that only the significance of haplotype GGA survived after Bonferroni adjustment (P = 0.044) and that no significant differences were found for other SGK1 SNPs (rs2758151, rs9493857, rs9376026, and rs9389154) between CHD patients with and without depression. These findings, for the first time, elucidate the important role of SGK1 variants in the comorbidity of CHD and depression.