Prothrombotic gene polymorphisms and plasma factors in young North Indian survivors of acute myocardial infarction

Association between homocysteine and coronary artery disease-trend over time and across the regions: a systematic review and meta-analysis

BACKGROUND

The association of homocysteine with coronary artery disease (CAD) has been explored previously with mixed findings. The present Systematic Review and Meta-Analysis (SRMA) has assessed the pooled estimate of association between homocysteine (Hcy) and CAD, and its variation over the period and geography.

METHODS

Systematic literature search was done in PubMed, Scopus and Cochrane to identify the observational studies that have reported mean Hcy among cases (CAD) and control. The SRMA was registered in PROSPERO (ID-CRD42023387675).

RESULTS

Pooled standardized mean difference (SMD) of Hcy levels between the cases and controls was 0.73 (95% CI 0.55-0.91) from 59 studies. Heterogeneity was high (I2 94%). The highest SMD was found among the Asian studies (0.85 [95% CI 0.60-1.10]), while the European studies reported the lowest SMD between the cases and controls (0.32 [95% CI 0.18-0.46]). Meta-regression revealed that the strength of association was increasing over the years (Beta = 0.0227, p = 0.048).

CONCLUSIONS

Higher homocysteine levels might have a significant association with coronary artery diseases, but the certainty of evidence was rated low, owing to the observational nature of the studies, high heterogeneity, and publication bias. Within the population groups, Asian and African populations showed a greater strength of association than their European and American counterparts, and it also increased over the years.

MTHFR gene polymorphisms and susceptibility to myocardial infarction: Evidence from meta-analysis and trial sequential analysis

Background

This meta-analysis aimed to provide a comprehensive assessment of the association between Methylenetetrahydrofolate reductase (MTHFR) gene polymorphisms, specifically C677T and A1298C, and the susceptibility to myocardial infarction (MI).

Methods

A systematic literature search was conducted in MEDLINE, Web of Science, and Scopus until April 2023 to identify studies investigating the relationship between MTHFR gene polymorphisms (C677T and A1298C) and the risk of MI.

Results

The analysis included 66 studies involving 16,860 cases and 20,403 controls for the C677T polymorphism and 18 studies comprising 3162 cases and 3632 controls for the A1298C polymorphism. Significant associations were observed between the C677T polymorphism and MI risk in various genetic models: dominant (OR = 1.16, 95 % CI = 1.06-1.28, P = 0.008), recessive (OR = 1.20, 95 % CI = 1.12-1.28, P < 0.001), allelic (OR = 1.13, 95 % CI = 1.06-1.21, P < 0.001), TT vs. CC (OR = 1.19, 95 % CI = 1.05-1.36, P < 0.001), and CT vs. CC (OR = 1.11, 95 % CI = 1.02-1.21, P = 0.01). Furthermore, an overall analysis indicated a marginally significant association between the A1298C polymorphism and MI risk in the recessive model (OR = 1.27, 95 % CI = 1.06-1.51, P = 0.008), allelic model (OR = 1.18, 95 % CI = 1.01-1.39, P = 0.03), and CC vs. AA model (OR = 1.22, 95 % CI = 1.01-1.47, P = 0.04). Meta-regression analysis revealed that none of the potential factors contributed to the observed heterogeneity.

Conclusions

This meta-analysis revealed an association between MTHFR gene C677T and A1298C polymorphisms and the risk of MI.

Risk factors, lab parameters, angiographic characteristics and outcomes of coronary artery disease in young South Asian patients: a systematic review

This systematic review provides a qualitative summary of the risk factors, angiographic characteristics, treatment, and complications of young South Asians with coronary artery disease (CAD). PubMed, Embase, and Google Scholar were searched to identify research articles published between 1 January 2010 and 13 November 2022. Studies in patients aged 18 to 45 years that were conducted in South Asian countries, were published in the English language, and included information on patients' clinical profiles and at least two risk factors for young CAD were included in the review. Smoking, dyslipidemia, high body mass index, increased high-sensitivity C-reactive protein, and hyperhomocysteinemia were observed in high proportions in young patients with CAD. Single-vessel disease was more common than multi-vessel disease in young CAD. The complications of CAD such as arrhythmias, cardiogenic shock, and heart failure were also commonly observed in young patients. Large-scale health promotion activities that curb modifiable risk factors such as smoking, obesity, and a sedentary lifestyle should be conducted in South Asian countries.

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.

Biochemical Association of MTHFR C677T Polymorphism with Myocardial Infarction in the Presence of Diabetes Mellitus as a Risk Factor

Myocardial infarction (MI) is a cardiovascular disease that occurs due to the blockage of the coronary artery. Subsequently, cardiac muscles receive a lower oxygen supply, which leads to the death of cardiac muscles. The etiology of MI is linked to various environmental, occupational, and genetic factors. Various studies have been conducted on the polymorphism of genes involved in MI. Previous studies have shown that different variants of the methylene tetrahydrofolate reductase (MTHFR) gene are involved in causing MI by altering the metabolism of folate and homocysteine. However, the genetic polymorphism of MTHFR C677T (rs1801133) and its association with MI in the presence of diabetes mellitus (DM) as a risk factor still needs to be investigated. This study recruited 300 participants who were divided into three groups, i.e., the control, MI, and MI-DM. The blood samples collected from the study participants were subjected to various biochemical tests and their clinical parameters were monitored. MTHFR C677T (rs1801133) genotyping was performed by Tetra ARMS PCR using predetermined primers. The MTHFR C677T (rs1801133) polymorphism was associated with MI in the presence of DM as a risk factor among the participants. The MTHFR C677T (rs1801133) T/T homozygous genotype was found to be significant among MI patients in the presence of DM as a risk factor.

Factor V Leiden but not the factor II 20210G>A mutation is a risk factor for premature coronary artery disease: a case-control study in Iran

Background

Factor V Leiden (FVL) and factor II c.∗97G>A (rs1799963) are genetic risk factors for venous thromboembolism. Their contribution to coronary artery disease (CAD) is less clear.

Objectives

This study aimed to investigate the association between FVL, rs1799963, and premature CAD in Iranians.

Methods

We performed a genetic case-control study of 944 cases and 1081 controls from the premature CAD Milano-Iran study, including patients aged 18-55 (female) and 18-45 years (male) who underwent coronary angiography at the Tehran Heart Centre (Iran) in 2004-2011. Cases had luminal stenosis ≥50% in at least 1 main coronary artery or branch. Controls were age- and sex-matched with no CAD history. FVL and rs1799963 were genotyped using TaqMan SNP genotyping assays. Association was tested by logistic regression adjusted for matching factors and ethnicity. Effect modification by sex and cardiovascular risk factors (metabolic [obesity, hypertension, hyperlipidemia, and diabetes], and smoking) was assessed.

Results

The risk of premature CAD was increased by 50% in FVL carriers (adjusted odds ratio [adjOR] 1.54 [95% CI, 0.95-2.48]) and slightly reduced in rs1799963 carriers (adjOR 0.71 [95% CI, 0.40-1.27]). These effects were more pronounced in women than men (FVL, adjOR 1.66 vs 1.25; rs1799963, adjOR 0.60 vs 1.07). The risk of premature CAD was substantially increased in carriers of FVL with at least 1 metabolic risk factor compared with noncarriers without metabolic risk factors (adjOR 25.14 [95% CI, 12.51-50.52]).

Conclusion

FVL but not FII rs1799963 was associated with an increased risk of CAD in young Iranians. This risk increased considerably when combined with metabolic cardiovascular risk factors.

Association of venous thromboembolism and myocardial infarction with Factor V Leiden and Factor II gene mutations among Libyan patients

Factor V Leiden G1691A (FVL) and Factor II prothrombin G20210A (PGM) mutations are the leading causes of thrombophilia. In this study, we have investigated the prevalence of the FVL G1691A and PGM G20210A single nucleotide polymorphisms (SNPs) among Libyan deep vein thrombosis (DVT) and myocardial infarction (MI) patients. SNP genotyping was performed using high-resolution melt analysis (HRM) and DNA sequencing. Biochemical parameters conducted on 112 males and 93 females showed no significant difference in means between the control group and the deep vein thrombosis and myocardial infarction groups. For Factor V Leiden, 40 samples were genotyped. Of the 40 samples, 6 (15.0%) of them were heterozygous and no one was homozygous. As for Factor II SNP, 59 samples were genotyped and only 2 (3.3%) were heterozygous. All the heterozygous samples showed 100% concordance between the HRM-PCR and DNA sequence analysis. Our study showed, for the first time, that both the FVL and PGM mutations are present among Libyan DVT and MI patients and that the FVL mutation is significantly associated with DVT but not with MI. However, our results do not support the association of PGM G20210A mutation with DVT or MI.

Correlation of rs1122608 SNP with acute myocardial infarction susceptibility and clinical characteristics in a Chinese Han population: A case-control study

Objective:

The correlation of the BRG1 rs1122608 single nucleotide polymorphism (SNP) with acute myocardial infarction (AMI) has been reported in American and European populations. However, whether rs1122608 acts as a protective factor or a risk factor for AMI is controversial. In this study, we aimed to detect the associations between rs1122608 and the clinical characteristics of AMI as well as susceptibility, gene–environment interactions, and risk factors for AMI in a Chinese Han population.

Methods:

In this study, 300 AMI patients and 300 healthy controls of Chinese Han ancestry were enrolled. PCR-RFLP was used to genotype rs1122608 SNPs. Genotypic and allelic frequencies of rs1122608 were compared between the AMI and control groups and among four AMI subgroups, which were subdivided by typical symptom, diagnosis time (DT), infarction location andserious complication.

Results:

Significant differences were detected between the AMI patients and the controls in both the genotypic and allelic frequencies of rs1122608 (p<0.001 for each). There were also interactions between the subjects with a minor T allele and smoking or alcohol consumption (p<0.001 for each).

Conclusion:

In the Chinese Han study population, the mutant GT and TT genotypes and minor T allele of rs1122608 were positively correlated with the risk of AMI. For the first time, we discovered that the GT genotype of the rs1122608 SNP is significantly correlated with diagnosis time of AMI. In addition, the interactions between the minor T allele of rs1122608 and smoking or alcohol use and between the rs1122608 CC genotype and alcohol use appear to increase the risk of AMI.

A systematic review of associations between non-communicable diseases and socioeconomic status within low- and lower-middle-income countries

Background

Non-communicable diseases (NCDs) are the leading cause of death globally. Eighty-two percent of premature NCD deaths occur within low- and lower middle-income countries (LLMICs). Research to date, largely drawn from high-income countries, suggests that disadvantaged and marginalized groups have a higher NCD burden, but there has been a dearth of research studying this relationship within LLMICs. The purpose of this systematic review is to map the literature on evidence from LLMICs on the socio-economic status (SES) gradient of four particular NCDs: cardiovascular disease, cancer, diabetes, and chronic respiratory diseases.

Methods

We conducted a comprehensive literature search for primary research published between 1 January 1990 and 27 April 2015 using six bibliographic databases and web resources. We included studies that reported SES and morbidity or mortality from cardiovascular disease, cancer, diabetes and chronic respiratory diseases within LLMICs.

Results

Fifty-seven studies from 17 LLMICs met our inclusion criteria. Fourteen of the 18 papers that reported significant associations between cancer and SES suggested that low SES groups had the highest cancer risk. Eleven of 15 papers reporting significant relationships between CVD and SES suggested that low SES groups have higher risk. In contrast, seven of 12 papers reporting significant findings related to diabetes found that higher SES groups had higher diabetes risk. We identified just three studies on the relationship between chronic respiratory diseases and SES; none of them reported significant findings.

Conclusions

Only 17 of the 84 LLMICs were represented, highlighting the need for more research on NCDs within these countries. The majority of studies were medium to high quality cross-sectional studies. When we restricted our analyses to high quality studies only, for both cancer and cardiovascular disease more than half of studies found a significantly higher risk for those of lower SES. The opposite was true for diabetes, whilst there was a paucity of high quality research on chronic respiratory disease. Development programmes must consider health alongside other aims and NCD prevention interventions must target all members of the population.

Systematic review registration number

Prospero: CRD42015020169.

Polymorphism of R353Q (rs6046) in factor VII and the risk of myocardial infarction: A systematic review and meta-analysis

OBJECTIVE

Genetic components substantially contribute to the development of myocardial infarction (MI), and R353Q polymorphism (rs6046) in FVII gene has been suspected to be associated with the risk of MI.

METHODS

A meta-analysis was conducted on the links between R353Q polymorphism and the susceptibility of MI. A comprehensive literature search was performed on 8 electronic databases. The main effects of the genotypes were estimated using a logistic regression approach. The odds ratios with 95% confidence intervals were calculated using the conventional summary method meta-analysis. The possible sources of heterogeneity among the included studies were explored using meta-regression analysis and subgroup analysis.

RESULTS

A total of 18 eligible case-control studies, comprising of 4701 cases and 5329 controls, were included. No overall statistical relationship was identified between R353Q and MI by any of the genetic models. The meta-regression demonstrated that the Asian population, body mass index (BMI) category, and diabetes affected the heterogeneity. In addition, subgroup analyses showed that heterogeneities were identified in Asian population and BMI category, which highly agree with the results of meta-regression.

CONCLUSIONS

The current meta-analysis suggested that R353Q polymorphism was not associated with the MI risk. Asian population, BMI category, and diabetes might be related to the incidence of MI. However, large-scale, case-control studies with rigorous designs are essential to provide accurate evidence.

Coagulation F13A1 V34L, fibrinogen and homocysteine versus conventional risk factors in the pathogenesis of MI in young persons

BACKGROUND

The pathogenesis of myocardial infarction (MI) involves environmental and genetic risk factors, with the latter putatively playing significant roles in younger patients. Genetic variability in coagulation factors comprises one such group. The coagulation factor 13 subunit A (F13A1) Val34Leu polymorphism (rs5985) has yielded variable findings in literature, with no prior South Asian data.

METHODS

We studied the frequency of this polymorphism using the amplification-created restriction-enzyme site (ACRES) polymerase chain reaction restriction fragment length polymorphism (PCR-RFLP) in 101 MI patients aged below 40 years and 103 controls along with plasma fibrinogen and serum homocysteine levels.

RESULTS

The distribution of Val/Val, Val/Leu and Leu/Leu genotypes was similar among cases (72.3%, 26.7% and 1.0%) and controls (78.6%, 19.4% and 1.9%, respectively). Val and Leu allele frequencies were 85.6% and 14.4% among patients and 88.3% and 11.7% among controls, respectively (p = .416). Mean plasma fibrinogen was higher in patients vis-à-vis controls (3.1 versus 3.7 g/l; p < .001) but homocysteine was elevated in both patients (52%) and controls (67%) (p = .225). Multivariate analysis revealed hypertension (p < .001, OR 6.16) and smoking (p < .001, OR 5.48) to impart strongest risk followed by positive family history, plasma fibrinogen levels and male gender.

CONCLUSIONS

Despite its small sample size, this first South Asian study suggests neither protective nor deleterious effects of the F13A1 Val34Leu polymorphism on the risk of MI in young persons. The Leu allele frequency is intermediate to that reported from the West and the Far East. Traditional risk factors contribute greatly to risk even in younger MI patients in South Asia.

Methylenetetrahydrofolate Reductase Gene Polymorphism (C677T) as a Risk Factor for Arterial Thrombosis in Georgian Patients

Methylenetetrahydrofolate reductase (MTHFR) gene polymorphism (C677T)] is a well-recognized genetic risk factor for venous thrombosis; however, its association with arterial thrombosis is still under debate. Herein, we evaluated the prevalence of MTHFR C677T polymorphism in Georgian patients in comparison with healthy individuals and its association with arterial thrombosis. We enrolled 214 participants: 101 with arterial thrombosis (71.3% males; mean age: 66.3 ± 12.1 years) and 113 controls (67.3% males; mean age: 56.6 ± 11.3 years). Genomic DNA was extracted from dry blood spot on Whatman filter paper. Polymerase chain reaction was performed to determine MTHFR C677T polymorphism. Frequency of C677T allele polymorphism in controls was 21.2%, which corresponded to heterozygous and homozygous stage frequencies of 35.4% and 3.5%, respectively. In patient group, an allelic frequency of 33.2% was found, which corresponded to the presence of 48.5% of heterozygous and 8.9% of homozygous individuals. Comparing the frequency of mutated alleles between the 2 groups, a significantly high frequency of mutated alleles was found in patient group (P < .05). In conclusion, high frequency of MTHFR C677T polymorphism found in arterial thrombosis patient group suggests that this polymorphism might increase the risk of arterial thrombosis in Georgian patients.

Association of Platelet Membrane Glycoprotein HPA-2a/b, GP VI T13254C, and GP Ibα VNTR Polymorphisms with Risk of Coronary Artery Disease: A Meta-Analysis

BACKGROUND AND AIMS

Recently, controversial results have been reported regarding the association of the polymorphisms of platelet membrane glycoproteins (HPA-2a/b, GP VI T13254C, and GP Ibα VNTR) with coronary artery disease (CAD). We performed this meta-analysis to further assess the polymorphisms of platelet membrane glycoproteins with a risk of CAD.

METHODS

A systematic electronic literature search was conducted in Embase, Cochrane Library, PubMed, and the Chinese Biomedical Literature Database (CBM). Analyses were performed using the Cochrane software package Review Manager 5.2 and Stata 12.0 software package.

RESULTS

Twenty-nine full-text articles were included in the meta-analysis. Based on random-effects meta-analysis, a significant association between the HPA-2a/b polymorphism and CAD was identified (allele model: odds ratio = 1.43, 95% confidence interval = 1.07-1.91; dominant genetic model: odds ratio = 1.57, 95% confidence interval = 1.08-2.28). Our study showed no association between the GP VI T13254C polymorphism and CAD in either a random-effects model or a fixed-effects model. Furthermore, there was no evidence to suggest that the GP Ibα VNTR polymorphism was associated with CAD in any of the genetic analysis models.

CONCLUSIONS

The HPA-2a/b polymorphism correlated significantly with a risk of CAD, and the HPA-2b allele and the HPA-2ab + HPA-2bb genotype may increase the risk of CAD. There was no evidence to suggest that polymorphisms of GP VI T13254C and GP Ibα VNTR were associated with CAD.

Common Variants of Vitamin D Receptor Gene Polymorphisms and Susceptibility to Coronary Artery Disease: A Systematic Review and Meta-Analysis

BACKGROUND AND AIMS

ApaI, FokI, TaqI, and BsmI polymorphisms in the vitamin D receptor (VDR) gene have been reported to be associated with the risk of coronary artery disease (CAD), although the results of previous studies have been inconsistent. The aim of this study was to explore whether these polymorphisms play a role in the genetic susceptibility to CAD.

METHODS

A comprehensive search of Medline and Embase databases was conducted for studies evaluating the association between the VDR polymorphisms and CAD risk. Odds ratios with 95% confidence intervals were calculated to assess the strength of association in the dominant model, recessive model, allelic model, and genotypes contrast.

RESULTS

Nine studies involving a total of 5,259 cases and 1,981 controls were finally included in this meta-analysis. Overall, no significant associations were found between ApaI, FokI, TaqI, and BsmI polymorphisms and the risk of CAD in any of the genetic models (all p ˃ 0.05). Moreover, a subgroup analysis by ethnicity did not reveal a significant relationship between any of the examined polymorphisms and CAD risk in Caucasians and East-Asians for any model (all p ˃ 0.05).

CONCLUSION

Current evidence suggests that the ApaI, FokI, TaqI, and BsmI polymorphisms of the VDR gene might not be associated with genetic susceptibility to CAD. Further well-designed studies with large sample sizes are needed to confirm our results.

C667T and A1298C polymorphisms of methylenetetrahydrofolate reductase gene and susceptibility to myocardial infarction: A systematic review and meta-analysis

MTHFR C677T and A1298C polymorphisms have been reported to be associated with the risk of myocardial infarction (MI), although the results of previous studies have been inconsistent. The aim of this study was to explore whether these polymorphisms play a role in the genetic susceptibility to MI. A comprehensive search of MEDLINE and EMBASE databases was conducted for studies evaluating the association between the C667T and A1298C polymorphisms and MI risk. Odds ratios (OR) with 95% confidence intervals (CIs) were calculated to assess the strength of association in the dominant model, recessive model, allelic model, and genotypes contrast. A total of 47 studies were finally included in this meta-analysis. Overall, the results showed no statistically significant association between C667T and A1298C polymorphisms and MI risk. However, in subgroup analysis by ethnicity, the T allele of C677T polymorphism was associated with a 63% increased risk of MI compared with the C allele (T vs. C, OR=1. 63, 95%CI=1.15-2.10, fixed effects) in African populations, while compared to wild homozygote genotype, CT genotype was associated with a decreased risk of MI in North American populations (CT vs. CC, OR=0.81, 95%CI=0.64-0.98, fixed effects). Moreover, C677T polymorphism had a protective effect against MI risk under the dominant model (OR=0.93, 945%CI=0.87-0.99, fixed effects) in elderly (≥50) population. The A1298C polymorphism was not significantly associated with MI risk. Unlike A1298C polymorphism, C677T polymorphism was associated with risk of MI in African, North American, and elderly populations.

Detection of human genome mutations associated with pregnancy complications using 3-D microarray based on macroporous polymer monoliths

Analysis of variations in DNA structure using a low-density microarray technology for routine diagnostic in evidence-based medicine is still relevant. In this work the applicability of 3-D macroporous monolithic methacrylate-based platforms for detection of different pathogenic genomic substitutions was studied. The detection of nucleotide replacements in F5 (Leiden G/A, rs6025), MTHFR (C/T, rs1801133) and ITGB3 (T/C, rs5918), involved in coagulation, and COMT (C/G, rs4818), TPH2 (T/A, rs11178997), PON1 (T/A rs854560), AGTR2 (C/A, rs11091046) and SERPINE1 (5G/4G, rs1799889), associated with pregnancy complications, was performed. The effect of such parameters as amount and type of oligonucleotide probe, amount of PCR product on signal-to-noise ratio, as well as mismatch discrimination was analyzed. Sensitivity and specificity of mutation detections were coincided and equal to 98.6%. The analysis of SERPINE1 and MTHFR genotypes by both NGS and developed microarray was performed and compared.

Association of seven thrombotic pathway gene CpG-SNPs with coronary heart disease

OBJECTIVES

Coronary heart disease (CHD) has been considered a thromboembolic arterial diseases. The aim of this case-control study was to explore whether the CpG-SNPs of the thrombotic pathway genes contributed to the risk of CHD.

METHODS AND MATERIALS

A total of 784 CHD patients and 738 healthy controls were recruited in the current association study, which evaluated 7 CpG-SNPs of the thrombotic pathway genes. The CpG-SNPs included THBS4 rs17878919, CYP2C19 rs12773342, P2RY12 rs1491974, ITGA2 rs26680, FGB rs2227389, F7 rs510317 and F5 rs2269648. SNP genotyping was performed with a Sequenom Mass Spectrometry Genetic Analyzer.

RESULTS

Our results demonstrated that CYP2C19 rs12773342 polymorphism was significantly associated with CHD in the recessive model (χ(2)=5.41, df=1, P=0.020, OR=1.455, 95% CI=1.060-1.996). A breakdown analysis by age showed that the association of CYP2C19 rs12773342 with CHD was mainly found in individuals aged 55-65 (genotype: χ(2)=7.93, df=2, P=0.019; allele: χ(2)=4.45, df=1, P=0.035). In addition, we also observed a significant association between F7 rs510317 polymorphism and CHD in males (genotype: χ(2)=7.24, df=2, P=0.027). There was no significant association with CHD for the remaining CpG-SNPs.

CONCLUSION

Our results supported that the CYP2C19 rs12773342 and F7 rs510317 polymorphisms were associated with CHD in the Han Chinese population.

Genetic polymorphism of MTHFR C677T and premature coronary artery disease susceptibility: A meta-analysis

The association between 5, 10-methylenetetrahydrofolate reductase (MTHFR) C677T gene polymorphism and premature coronary artery disease (PCAD) is controversial. To explore a more precise estimation of the association, a meta-analysis was conducted in the present study. The relevant studies were identified by searching PubMed, EMBASE, the Web of Science, Cochrane Collaboration Database, Chinese National Knowledge Infrastructure, Wanfang Database and China Biological Medicine up to November, 2014. The meta-analysis was performed by STATA 11. 21 studies with a total of 6912 subjects, including 2972 PCAD patients and 3940 controls. The pooled analysis showed that MTHFR C677T gene polymorphism was probably associated with PCAD (CT vs. CC: OR=1.13, 95% CI=1.01-1.27; dominant model: OR=1.16, 95% CI=1.04-1.29; recessive model: OR=1.19, 95% CI=1.00-1.40; allele analysis: OR=1.17, 95% CI=1.01-1.34). Subgroup analysis by plasma homocysteine concentration showed a significant association in the homocysteine >15μmol/L subgroup (CT vs. CC: OR=1.44, 95% CI=1.10-1.88; TT vs. CC: OR=2.51, 95% CI=1.12-5.63; dominant model: OR=1.51, 95% CI=1.16-1.96; recessive model: OR=2.33, 95% CI=1.05-5.20; allele analysis: OR=1.48, 95% CI=1.18-1.87). Subgroup analysis by continent displayed a significant association among the Asian population (CT vs. CC: OR=1.51, 95% CI=1.23-1.86; TT vs. CC: OR=2.81, 95% CI=1.87-4.23; dominant model: OR=1.65, 95% CI=1.35-2.01; recessive model: OR=2.22, 95% CI=1.53-3.21; allele analysis: OR=1.61, 95% CI=1.37-1.89). The statistical stability and reliability was demonstrated by sensitivity analysis and publication bias outcomes. In conclusion, the meta-analysis suggests that MTHFR C677T gene polymorphism may be associated with PCAD.

Genetic polymorphisms, Biochemical Factors, and Conventional Risk Factors in Young and Elderly North Indian Patients With Acute Myocardial Infarction

This study compared genetic polymorphisms (factor V Leiden [FVL] 1691G/A, factor VII [FVII] 10976G/A, FVII HVR4, platelet membrane glycoproteins GP1BA 1018C/T, GP1BA VNTR, integrin ITGB3 1565T/C, ITGA2 807C/T and methylenetetrahydrofolate reductase [MTHFR] 677C/T), biochemical (fibrinogen and homocysteine), and conventional risk factors in 184 young and 166 elderly north Indian patients with acute myocardial infarction (AMI). Univariate analysis revealed higher prevalence of hypertension and obesity in elderly patients while smoking, alcohol intake, and low socioeconomic status in young patients (P < .001). Although mean fibrinogen predominated (P = .01) in elderly patients, mean homocysteine was higher (P < .001) among young patients. Prevalence of hyperhomocysteinemia was greater in young than in elderly patients (odds ratio: 2.8, 95% confidence interval: 1.8-4.4, P < .001); however, genetic polymorphisms were equally prevalent in young and elderly patients. Multiple logistic regression analysis showed smoking (P < .001), alcohol intake (P = .046), and hyperhomocysteinemia (P = .001) to be associated with AMI in the young patients while hypertension (P = .006) in elderly patients. To conclude, smoking, alcohol intake, and elevated homocysteine are the risk factors for AMI among young while hypertension among elderly patients.

The PlA1/A2 polymorphism of glycoprotein IIIa as a risk factor for myocardial infarction: a meta-analysis

BACKGROUND

The PlA2 polymorphism of glycoprotein IIIa (GPIIIa) has been previously identified as being associated with myocardial infarction (MI), but whether this represents a true association is entirely unclear due to differences in findings from different studies. We performed a meta-analysis to evaluate whether this polymorphism is a risk factor for MI.

METHODS

Electronic databases (MEDLINE and EMBASE) were searched for all articles evaluating genetic polymorphisms of GPIIIa. For studies where acute coronary events were recorded in association with genetic analysis, pooled odds ratios (ORs) were calculated using fixed-effects and random-effects models. The primary outcome measure was MI, and a secondary analysis was also performed for acute coronary syndromes (ACS) more generally.

FINDINGS

57 studies were eligible for statistical analysis and included 17,911 cases and 24,584 controls. Carriage of the PlA2 allele was significantly associated with MI (n = 40,692; OR 1.077, 95% CI 1.024-1.132; p = 0.004) but with significant publication bias (p = 0.040). The degree of association with MI increased with decreasing age of subjects (≤45 years old: n = 9,547; OR 1.205, 95% CI 1.067-1.360; p = 0.003) and with adjustment of data for conventional cardiovascular risk factors (n = 12,001; OR 1.240, 95% CI 1.117-1.376; p<0.001). There was a low probability of publication bias for these subgroup analyses (all p<0.05).

CONCLUSIONS

The presence of significant publication bias makes it unclear whether the association between carriage of the PlA2 allele and MI is true for the total population studied. However for younger subjects, the relative absence of conventional cardiovascular risk factors results in a significant association between carriage of the PlA2 allele and MI.

Acute myocardial infarction: Clinical features and outcomes in young adults in Singapore

AIM

To investigate the clinical features and in-hospital outcomes of young adults with acute myocardial infarction (AMI) in Singapore.

METHODS

Between January 2005 to September 2010, 333 consecutive patients aged ≤ 45 years old were diagnosed to have AMI at our institution. As Singapore is a multi-ethnic society, we also analysed whether ethnic differences exist between the three dominant ethnic groups, Malay, Chinese and Indian with regards to the clinical features. Clinical data was collected retrospectively on demographic characteristics, presenting signs and symptoms, blood investigation, angiographic findings and in-hospital clinical outcomes.

RESULTS

The mean age at presentation was 40.2 ± 4.0 years with male predominance (94%). The majority of patients were Chinese (51%) followed by Indians (31%) and Malays (18%). The most common risk factor was smoking (74%) followed by hypertension (28.5%) and hyperlipidemia (20.0%). 37% of patients were obese. The majority of patients had single vessel disease (46%) on coronary angiography. The mean total cholesterol, low-density lipoprotein and high-density lipoprotein levels were 5.6 ± 1.2 mmol/L, 3.8 ± 1.1 mmol/L and 0.93 ± 0.25 mmol/L respectively. The mean left ventricular function was 44% ± 10% with the incidence of heart failure 3% and cardiogenic shock 4.5%. Overall in-hospital mortality was low with 4 deaths (1.2%). For ethnic subgroup analysis, Indians have a 3-fold risk of developing premature AMI when compared to other ethnic groups.

CONCLUSION

Young AMI patients in Singapore are characterized by male predominance, high incidence of smoking and obesity. Overall in-hospital clinical outcomes are favourable. Among the 3 ethnic groups, Indians have the highest risk of developing premature AMI.