Gene polymorphisms in patients below 35 years of age who underwent coronary artery bypass surgery

Acute Myocardial Infarction in Patients with Hereditary Thrombophilia-A Focus on Factor V Leiden and Prothrombin G20210A

Factor V (FV) Leiden and prothrombin G20210A are the most common hereditary thrombophilias. While their role in venous thromboembolism is well known, there are still uncertainties regarding their relationship with arterial thrombotic events, especially coronary ones. Our research, based on an in-depth analysis of the available literature, provides up-to-date information on the relationship between FV Leiden and prothrombin G20210A and acute myocardial infarction. FV Leiden and prothrombin G20210A screening should be implemented only in select cases, such as acute coronary syndrome in young individuals and/or in the absence of traditional cardiovascular risk factors and/or in the absence of significant coronary artery stenosis at angiography. Their identification should be followed by the implementation of optimal control of modifiable traditional cardiovascular risk factors to reduce the risk of recurrent events and genotyping and genetic counseling of all family members of affected cases for proper prophylaxis. An extended dual antiplatelet therapy (DAPT) may be considered, given the lower risk of bleeding under DAPT conferred by FV Leiden.

Association of interleukin 6 -174 G/C polymorphism with coronary artery disease and circulating IL-6 levels: a systematic review and meta-analysis

INTRODUCTION

Circulating IL-6 levels and at least one polymorphic form of IL6 gene (IL6 -174 G/C, rs1800795) have been shown to be independently associated with coronary artery disease (CAD) by several investigators. Despite more than 12 published meta-analyses on this subject, association of -174 G/C with CAD, especially amongst distinct ancestral population groups remain unclear. We, therefore, conducted a systematic review and an updated meta-analysis to comprehensively ascertain the association of IL6 -174 G/C with CAD and circulating IL-6 levels.

MATERIALS AND METHODS

Relevant case-control/cohort studies investigating association of -174 G/C with CAD and circulating IL-6 levels were identified following a comprehensive online search. Association status for CAD was determined for the pooled sample, as well as separately for major ancestral subgroups. Association status for circulating IL-6 levels was assessed for the pooled sample, as well as separately for CAD cases and CAD free controls. Study-level odds ratios (OR) and 95% confidence intervals (CI) were pooled using random/fixed-effects model.

RESULTS

Quantitative synthesis for the CAD endpoint was performed using 55 separate qualifying studies with a collective sample size of 51,213 (19,160 cases/32,053 controls). Pooled association of -174 G/C with CAD was found to be statistically significant through dominant (OR 1.15; 95% CI 1.05-1.25, p = 0.002) as well as allelic genetic model comparisons (OR 1.13, 95% CI 1.06-1.21, p = 0.0003). This effect was largely driven by Asian and Asian Indian ancestral subgroups, which also showed significant association with CAD in both genetic model comparisons (OR range 1.29-1.53, p value range ≤ 0.02). Other ancestral subgroups failed to show any meaningful association. Circulating IL-6 levels were found to be significantly higher amongst the 'C' allele carriers in the pooled sample (Standard mean difference, SMD 0.11, 95% CI 0.01-0.22 pg/ml, p = 0.009) as well as in the CAD free control subgroup (SMD 0.10, 95% CI 0.02-0.17 pg/ml, p = 0.009), though not in the CAD case subgroup (SMD 0.17, 95% CI = - 0.02 to 0.37, p = 0.12).

CONCLUSIONS

The present systematic review and meta-analysis demonstrate an overall association between IL6 -174 G/C polymorphism and CAD, which seems to be mainly driven by Asian and Asian Indian ancestral subgroups. Upregulation of plasma IL-6 levels in the 'C' allele carriers seems to be at least partly responsible for this observed association. This warrants further investigations with large, structured case-control studies especially amongst Asian and Asian Indian ancestral groups.

The effect of polymorphisms (174G> C and 572C> G) on the Interleukin-6 gene in coronary artery disease: a systematic review and meta-analysis

Background

Coronary Artery Disease (CAD) is caused by the blockage of the coronary arteries. it is argued that there has an association between the Interleukin-6 gene and the occurrence of atherosclerosis, coronary artery disease, Due to the short half-life and high variability of Interleukin-6 (IL-6), limited studies have been performed on the association of serum levels of interleukin-6 with coronary artery disease. The aim of this study is to investigate the relationship between IL-6 gene polymorphisms and coronary artery disease.

Methods

This study was conducted as a meta-analysis of selected articles with no lower time limit and upto March 2020. Articles related to the subject were obtained by searching several data sources,such as the SID, IranDoc, Scopus, Embase, Web of Science (ISI), PubMed, Science Direct, and Google Scholar databases. The heterogeneity of the studies was assessed using the I² index in the Comprehensive Meta-Analysis software.

Results

The GG genotype of the IL-6174 G> C polymorphism with a 0.8 odds ratio tended to reduce the risk of CAD by 20%. The odds ratio of CAD in CG and GG genotypes were found to be 1.16 and 1.48 times respectively, indicating the increasing effect of these two genotypes. In the IL-6-572 C>G polymorphism, CG and GG genotypes increased the risk of CAD by 1.21 and 1.27 times respectively, and the CC genotype tended to reduce the risk of CAD by 15%, considering the odds ratio of 0.85.

Conclusion

This study showed a relationship between IL-6174G> C and Interleukin-6 (IL-6) 572 C>G genes and coronary artery disease. Moreover, the protective effects of GG genotype in IL-6 gene 174 G> C and CC genotype in IL-6 gene 572 C>G gene were reported. The study also confirmed that the CG and CC genotypes of the G>C IL-6174 gene have an increasing effect on coronary artery disease. Moreover, CG and GG genotypes in the IL-6 gene 572 C>G increased the risk of developing CAD. It should be noted that the increased risk of developing CAD was limited to meta-analytic studies in reported literatures.

Systematic review and meta-analysis of association of polymorphisms in inflammatory cytokine genes with coronary artery disease

BACKGROUND

It has comprehensively been acknowledged that a genetic contribution, especially in immune inflammatory players, such as interleukin (IL)-6 and tumor necrosis factor (TNF)-α, are critically involved in the pathophysiology of coronary artery disease (CAD). This meta-analysis study aimed to reach a conclusive understanding of the role of genetic polymorphisms, including IL6 gene C572G (rs1800796) and G174C (rs1800795) as well as TNFA gene G238A (rs361525) and G308A (rs1800629) in susceptibility to CAD.

METHODS

Two major databases, namely MEDLINE and Scopus, were searched to find the studies surveying the mentioned polymorphisms and CAD susceptibility up to July 2020. Association comparison between the polymorphisms and CAD susceptibility were assessed using pooled odds ratio (OR) and their corresponding 95% confidence interval (CI).

RESULTS

This meta-analysis study was conducted on 69 papers (73 population studies), comprising 5062 patients and 8446 controls for IL6 gene rs1800796 (17 studies), 13801 patients and 16215 controls for IL6 gene rs1800795 (38 studies), 1439 patients and 2850 controls for TNFA gene rs361525 (5 studies), and 5051 patients and 3958 controls for TNFA gene rs1800629 (13 studies), according to inclusion and exclusion criteria. There were statistically positive association between all genetic comparisons of IL6 gene rs1800795 polymorphism and the CAD risk. Moreover, the recessive model (CC vs. CG + GG) in IL6 gene rs1800796 polymorphism had marginally significant association with decreased risk of CAD. None of the TNFA gene polymorphisms were associated with CAD risk.

CONCLUSIONS

The meta-analysis revealed the positive association of IL6 gene rs1800795 polymorphism in susceptibility to CAD.

Interleukin 6 (rs1800795) gene polymorphism is associated with cardiovascular diseases: a meta-analysis of 74 studies with 86,229 subjects

Cardiovascular diseases (CVD) are group of complex and multifactorial pathologies, in which interleukin-6 (IL-6) gene polymorphisms have been associated with several components of the CVD. Thus, in this study, we thoroughly reviewed and meta-analyzed evidence on the association between the IL-6 (rs1800795) gene polymorphism and CVD. We systematically searched in the PubMed, Web of Sciences, and Scopus databases. The analyses were performed using five study groups based on (1) a combined pool of the overall populations, (2) the country of birth, (3) the continent of birth, (4) the diagnosis and (5) both location (country or continent) and diagnosis. The analysis included the allelic, homozygote, heterozygote, dominant and recessive models. The meta-analysis showed that -174G>C (rs1800795) is a risk factor for CVD (allelic: OR=1.06, CI 95%=1.02-1.10. Z p value <0.0001; homozygous: OR=1.11, CI 95%=1.03-1.19, Z p value= 0.002; heterozygous: OR=1.08, CI 95%=1.03-1.21, Z p value= 0.003; dominant: OR= 1.12, CI 95%= 1.07-1.18, Z p value= 0.001) and that this risk increases in the Chinese population. Additionally, we found that carriers of the C allele of 174G>C (rs1800795) polymorphism have an increase in the risk of coronary artery disease under the hereditary models assessed in the study. Using robust data, we found that IL-6 (rs1800795) -174G>C gene polymorphism is associated with CVD risk.

An Evidence-Based Meta-Analysis on the Roles of Functional Interleukin-6 Polymorphisms in Coronary Artery Disease

Recently, the relationship between functional interleukin-6 (IL-6) polymorphisms and coronary artery disease (CAD) was extensively studied, with controversial findings. Therefore, we conducted this meta-analysis to better elucidate the relationship between these polymorphisms and the risk of CAD. A total of 57 case-control studies were finally included. The overall analyses showed that IL-6 -174G>C and -572G>C polymorphisms were significantly associated with the risk of CAD, the C allele of -174G>C (G versus C, odds ratio [OR] = 0.82, confidence interval [95% CI] = 0.75-0.89) and -572G>C polymorphisms (G versus C, OR = 0.82, 95% CI = 0.74-0.92) conferred an increased susceptibility to CAD. Further subgroup analyses yielded similar positive results for -174G>C polymorphism in Asian and Caucasian populations, and for -572G>C polymorphism in Asian and African populations. In conclusion, our findings suggest that IL-6 -174G>C and -572G>C polymorphisms may serve as potential genetic markers of CAD.

Influence of interleukin-6 gene -174G>C polymorphism on development of atherosclerosis: a meta-analysis of 50 studies involving 33,514 subjects

Increasing epidemiological studies have focused on the associations between interleukin-6 (IL-6) gene -174G>C polymorphism and atherosclerotic diseases, but the results are still controversial. This meta-analysis was designed to identify whether this association exists. PubMed, Embase, Web of Science, Cochrane database, Clinicaltrials.gov and Current Controlled Trials, Chinese Clinical Trial Registry, CBMdisc, CNKI and Google Scholar were searched to get the genetic association studies. The crude odds ratios (ORs) and their corresponding 95% confidence intervals (CIs) were used to estimate the association between the IL-6 gene -174G>C polymorphism and atherosclerosis ( AS ) risk. The subgroup analyses were made on the following: ethnicity, atherosclerotic diseases and source of controls. Finally, 50 studies (15,029 cases and 18,485 controls) were included in this meta-analysis. Overall, no significant association was found between the IL-6 gene -174G>C polymorphism and AS risk (for C allele vs. G allele: OR=1.02, 95% CI=0.94-1.11, p=0.64; for C/C vs. G/G: OR=1.01, 95% CI=0.85-1.21, p=0.88; for C/C vs. C/G+G/G: OR=0.97, 95% CI=0.84-1.12, p=0.68; for C/C+C/G vs. G/G: OR=1.07, 95% CI=0.97-1.17, p=0.18). In the subgroup analyses, significant associations were found between the IL-6 gene -174G>C polymorphism and AS in non-Caucasian group (for CC+CG vs. GG: OR=1.22, 95% CI=1.06-1.41, p=0.005), other atherosclerotic diseases group (for C allele vs. G allele: OR =0.75, 95% CI=0.61-0.93, p=0.008; for C/C vs. G/G: OR=0.56, 95% CI=0.38-0.81, p=0.002; for C/C vs. C/G+G/G: OR=0.60, 95% CI=0.45-0.79, p=0.0004) and population-based group (for C allele vs. G allele: OR=1.09, 95% CI=1.00-1.18, p=0.04; for CC+CG vs. GG: OR=1.15, 95% CI=1.04-1.27, p=0.005). In summary, the present meta-analysis suggests that the IL-6 gene -174G C polymorphism is associated with the susceptibility to AS. However, due to the high heterogeneity in the meta-analysis, the results should be interpreted with caution.

Association between interleukin-6 gene -174 G/C polymorphism and the risk of coronary heart disease: a meta-analysis of 20 studies including 9619 cases and 10,919 controls

Interleukin-6 (IL-6) gene -174 G/C polymorphism has been reported to be associated with coronary heart disease (CHD), but the results remain inconclusive. The present meta-analysis was therefore designed to clarify these controversies. This meta-analysis was performed by searching PubMed, Embase and Web of Science databases. A total of 20 studies including 9619 CHD cases and 10,919 controls were combined showing no evidence of association between IL-6 gene -174 G/C polymorphism and CHD risk (for C/C+C/G vs. G/G: OR=1.10, 95% CI=0.99-1.22, p=0.07; for C/C vs. C/G+G/G: OR=1.08, 95% CI=0.93-1.24, p=0.33; for C/C vs. G/G: OR=1.16, 95% CI=0.97-1.39, p=0.11; for C allele vs. G allele: OR=1.10, 95% CI=1.00-1.21, p=0.06). Moreover, we also did not find significant association between IL-6 gene -174 G/C polymorphism and myocardial infarction (MI) risk. However, in the subgroup analysis by ethnicity, significant association was found among Asians (for C/C+C/G vs. G/G: OR=1.35, 95% CI=1.05-1.63, p=0.02). In summary, the present meta-analysis suggests that IL-6 gene -174 G/C polymorphism is associated with increased CHD risk among Asians. However, due to the small subjects included in the subgroup analysis of Asians, the results should be interpreted with caution.

Role of Genetic Polymorphism of Angiotensin-Converting Enzyme, Plasminogen Activator Inhibitor-1 and Endothelial Nitric Oxide Synthase in the Prognosis of Coronary Artery Disease

Background

This study was to investigate the effects of multiple genetic polymorphisms and conventional risk factors in the prognosis of coronary artery disease (CAD).

Methods

One hundred and fifty five patients with CAD were prospectively recruited, they were subgrouped as single vessel disease (SVD) and multiple vessel disease (MVD). All patients were detected I/D polymorphism of angiotensin-converting enzyme (ACE) gene, 4G/5G polymorphism of plasminogen activator inhibitor-1 (PAI-1) gene, and G894→T mutation of endothelial nitric oxide synthase (eNOS) gene. The patients were followed up for 10-65 months, mean 35 months. End points were major adverse cardiovascular events (MACE), including angina, myocardial infarction, and cardiac sudden death.

Results

During the follow-up period, MACE developed in 81 patients, 73 patients with angina, seven with myocardial infarction, and one with cardiac sudden death. CAD patients with MVD were more probable of developing MACE during follow-up. Distribution of PAI-1 gene polymorphism was significantly different between SVD and MVD patients, p < 0.001. The frequency of DD genotype of ACE and 4G/4G genotype of PAI-1 in patients with MACE were significantly higher than those in patients without MACE, p < 0.001 and p = 0.002, respectively. Incidence of diabetes mellitus was significantly higher in patients with MACE than in patients without MACE, P = 0.03. Cox regression analysis showed that diabetes mellitus (HR 2.36, 95% CI 1.33-4.46, p = 0.003), 4G/4G polymorphism of PAI-1 gene (HR 3.45, 95% CI 1.71-6.56, p = 0.009), and D/D polymorphism of ACE gene (HR 2.99, 95% CI 1.84-5.76, p = 0.005), were independent predictors of the MACE.

Conclusions

Our results showed that the conventional risk factors and genetic polymorphisms have significant influence on prognosis of CAD patients. CAD patients with diabetes mellitus, DD genotype of ACE, and 4G/4G genotype of PAI-1 suggested poor prognosis.

Varied association of prothrombin G20210A polymorphism with coronary artery disease susceptibility in different ethnic groups: evidence from 15,041 cases and 21,507 controls

Published data on the association between prothrombin G20210A polymorphism and coronary artery disease (CAD) risk are inconclusive. To derive a more precise estimation of the relationship, a meta-analysis was performed. A total of 42 case-control studies including 15,041 cases and 21,507 controls were included in this meta-analysis. Overall, significantly elevated CAD risk was associated with prothrombin G20210A polymorphism (OR, 1.22; 95% CI 1.07-1.40; P=0.003) when 39 eligible studies were pooled into the meta-analysis. In the subgroup analysis, borderline statistically increased risk was found for myocardial infarction in 22 case-control studies (OR, 1.27; 95% CI 1.00-1.61; P=0.05). When stratified by ethnicity, significantly elevated risk was found in Europeans (OR, 1.19; 95% CI, 1.02-1.38; P=0.02). However, no statistical differences were found among Americans and Asians. In summary, this meta-analysis indicated that prothrombin G20210A allele is a low-penetrant risk factor for developing CAD in Europeans.

No association of interleukin-6 gene polymorphism (-174 G/C) with premature coronary artery disease in a Turkish cohort

OBJECTIVES

Interleukin-6 (IL-6) may contribute to the inflammatory response by activating endothelial cells and stimulating the synthesis of fibrinogen. It might thus be important in the pathogenesis of inflammation associated with coronary artery disease (CAD). Several studies suggested that the -174 C allele was associated with an increased prevalence of coronary heart disease. The aim of this study was to investigate further the association of the IL-6 -174 G/C allele status with premature CAD.

METHODS

A total of 120 patients and 105 controls were included in the study. The IL-6 -174 G/C polymorphism was genotyped using PCR-restriction fragment length polymorphism.

RESULTS

The genotype distribution of the -174 G/C polymorphism was not different in premature CAD patients (GG: 53%; GC: 42.6%; CC: 4.3%) and controls (GG: 54.3%; GC: 39%; CC: 6.7%) (P=0.72). The prevalence of the C allele was 25.6% in patients and 26.1% in controls. By multiple regression analysis, family history, smoking, diabetes, and hypertension were independent risk factors of premature CAD, but not IL-6 genotype.

CONCLUSIONS

We conclude that the IL-6 -174 G/C polymorphism is not associated with the risk of premature CAD, and does not contribute to cardiovascular risk stratification.