Clinical application of genetic risk assessment strategies for coronary artery disease: genotypes, phenotypes, and family history

Polymorphism of HDAC9 Gene Is Associated with Increased Risk of Acute Coronary Syndrome in Chinese Han Population

Recent genome-wide association studies (GWAS) have indicated an association of histone deacetylase 9 (HDAC9) genetic variant with large-vessel stroke and coronary artery disease, among the European population. However, whether HDAC9 gene is associated with an increased susceptibility to acute coronary syndrome (ACS) in Chinese Han population is not known. A total of 472 patients, including patients with ACS (N = 309), and those with chest pain syndrome (controls, N = 163) were enrolled. Genotyping for HDAC9 gene was performed using the ligation detection reaction assay. A series of statistical analyses were performed to investigate the correlation between HDAC9 gene SNPs and the susceptibility to ACS. The results revealed a significant association of rs2240419 with ACS risk in which the A allele (P = 0.047) and the A allele carriers (AA + AG) (P = 0.037) were more likely to be in ACS group as compared to those in the control group. None of two other SNPs, rs2389995 and rs2107595, were significantly associated with ACS risk (P > 0.05). Logistic regression analyses further revealed an increased risk for ACS in A allele carrier among rs2240419 genotypes, as compared to those with GG homozygotes (odds ratio: 1.869, 95% CI 1.143, 3.056, P = 0.013). A significant correlation between rs2240419 polymorphism of HDAC9 gene and the susceptibility to ACS in Chinese Han population was observed in this study.

Association of Cholesteryl Ester Transfer Protein and Endothelial Nitric Oxide Synthase Gene Polymorphisms With Coronary Artery Disease in the Multi-Ethnic Malaysian Population

Genetic variants of cholesteryl ester transfer protein (CETP) and endothelial nitric oxide synthase (eNOS) influence high-density lipoprotein cholesterol (HDL-C) metabolism and nitric oxide (NO) synthesis, respectively, and might increase the risk of coronary artery disease (CAD). This study is to investigate the relationship between genetic polymorphisms and the risk of CAD and to evaluate their potential interactions. A total of 237 patients with CAD and 101 controls were genotyped. The association of the polymorphism with the risk of CAD varied among the ethnic groups. Moreover, the concomitant presence of both CETP B1 and eNOS 4a alleles significantly increased the risk of CAD in the Malay group (OR = 33.8, P < .001) and the Indian group (OR = 10.9, P = .031) but not in the Chinese group. This study has identified a novel ethnic-specific gene–gene interaction and suggested that the combination of CETP B1 allele and eNOS 4a allele significantly increases the risk of CAD in Malays and Indians.

Association between second-hand smoking and acute coronary heart disease among Arab women with multiple risk factors

BACKGROUND

Active smoking is a well-established risk factor for coronary heart disease (CHD). However, the role of second-hand smoking (SHS) needs further investigation. We aimed to study the association between SHS and CHD in Arab women in Israel.

METHODS

A matched case-control study among non-smoking Arab women. The case group included women discharged from hospital after having acute coronary event. The control group was women without CHD who were individually matched for age and type-2 diabetes. The women were interviewed with structured questionnaires on exposure to SHS and on attitudes towards such exposure, and underwent anthropometric measurements.

RESULTS

A total of 146 women were included, the majority had type-2 diabetes (68.5%) and were overweight or obese (89.4% of cases and 93.2% of controls, P = 0.727). The prevalence of exposure to domestic-SHS after marriage was higher among the cases than controls (91.8% vs. 53.4%, P < 0.001). After adjustment for hypertension, body mass index > 25 and family history, exposure to domestic-SHS after marriage was an independent risk factor for CHD (OR = 6.1, 95% CI 1.93-19.3). Compared with no exposure, the exposed for 2-6 h a day had an OR of 5.68 (1.48-21.73), and for >6 h a day the OR reached 26.12 (4.26-159.92). Women with CHD felt less comfortable voicing their concern about smoking near them and more highly agreed with prohibition of smoking.

CONCLUSIONS

Exposure to domestic-SHS is independently associated with CHD in Arab women, with a strong dose-response relationship, emphasizing the need for public health initiatives to reduce exposure to domestic-SHS.

Identification of Predictable Biomarkers in Conjunction to Framingham Risk Score to Predict the Risk for Cardiovascular disease (CVD) in Non Cardiac Subjects

INTRODUCTION

Although the cardiovascular disease (CVD) burden is rising in different countries, the morbidity and mortality rate is not reduced to much extent because of lack of application of the biomarkers for diagnosing CVD. Hence, we aimed to establish the predictable biomarkers in conjunction to framingham risk score in order to predict the risk for CVD in non cardiac patients.

MATERIALS AND METHODS

Three hundred subjects were screened for the study who came for the master health checkup. Out of them 50 patients were excluded as they were under medication. 23 patients were excluded due to various systemic diseases like fever and infection etc. The remaining of 227 patients with age range of 30-80 y was randomly selected for investigation. These subjects were divided into four different groups: Group I - controls with age range: 30-60 y (n=50) these subjects were free from all the systemic ailments and risk factors. Study groups comprised of Group II - (n=44) with age range: 30-40 y, Group III - (n=50) with age range: 41-50 y and Group IV - (n=83) with age range: 51-80 y. Patients with different risk factors without medication participated as study groups. Routine biochemical parameters were analysed using fully automated analyser and atherosclerotic biomarkers was analysed using ELISA kit. In addition to this, framingham risk scores was calculated in all the groups, for 30 y risk prognosis for CVD.

RESULTS

The atherosclerotic biomarkers such as E-selectin, Leptin, osteoprotegerin (OPG) and Ox-LDL were elevated among the study groups as compared to control group. Pearson correlation showed a significant association between the individual risk score (30 y framingham risk for CVD) of individuals, and the above biomarkers. The Receiver operating curve (ROC) analysis also showed a greater area under curve with higher sensitivity and specificity.

CONCLUSION

We conclude the application E-Selectin, leptin, OPG and Ox-LDL as biomarkers along with the framingham risk scores in prediction risk for CVD in the individuals with subclinical atherosclerosis. It is more reliable and predictable as compared to the individual biomarkers alone.

Parental consanguinity and family history of coronary artery disease strongly predict early stenosis

BACKGROUND

Coronary artery disease (CAD) is a multifactorial disease with acquired and inherited components.

AIM

We investigated the roles of family history and consanguinity on CAD risk and age at diagnosis in 4284 patients. The compounded impact of diabetes, hyperlipidemia, hypertension, smoking, and BMI, which are known CAD risk factors, on CAD risk and age at diagnosis was also explored.

METHODS

CAD was determined by cardiac catheterization. Logistic regression and stratification were performed to determine the impact of family history and consanguinity on risk and onset of CAD, controlling for diabetes, hyperlipidemia, hypertension, smoking, and BMI.

RESULTS

Family history of CAD and gender significantly increased the risk for young age at diagnosis of CAD (p<0.001). Consanguinity did not promote risk of CAD (p=0.38), but did affect age of disease diagnosis (p<0.001). The mean age at disease diagnosis was lowest, 54.8 years, when both family history of CAD and consanguinity were considered as unique risk factors for CAD, compared to 62.8 years for the no-risk-factor patient category (p<0.001).

CONCLUSIONS

Family history of CAD and smoking are strongly associated with young age at diagnosis. Furthermore, parental consanguinity in the presence of family history lowers the age of disease diagnosis significantly for CAD, emphasizing the role of strong genetic and cultural CAD modifiers. These findings highlight the increased role of genetic determinants of CAD in some population subgroups, and suggest that populations and family structure influence genetic heterogeneity between patients with CAD.

The factor V G1691A, factor V H1299R, prothrombin G20210A polymorphisms in children with family history of premature coronary artery disease

Atherosclerosis, the major cause of coronary artery disease (CAD), has a very long asymptomatic development phase, which begins in childhood. In this study, we describe the factor V G1691A, factor V H1299R and prothrombin G20210A gene polymorphisms in children with a family history of premature CAD. Evidence of these polymorphisms in these children may predict the probability of having atherosclerosis in the future. Our study included a total of 140 children, 72 males and 68 females between the ages of 4.9 and 15.7 years. Among these children, 73 had a parental history of premature CAD and the remaining 67 belonged to our control group. The participants were screened for the mutations factor V G1691A, factor V H1299R and prothrombin G20210A by polymerase chain reaction amplified DNA products with specific oligonucleotide probes. Our results suggested that frequencies of the mutated allele of factor V G1691A and prothrombin G20210A are higher in children with a parental history of premature CAD. In conclusion, factor V G1691A and prothrombin G20210A polymorphisms which were detected in higher frequencies in children with a parental history of premature CAD may indicate a risk for developing atherosclerosis and might be useful in screening for CAD in children; however, large population-based research is necessary to investigate further genetic risk assessment for CAD.

Plasma homocysteine concentrations and serum lipid profile as atherosclerotic risk factors in subclinical hypothyroidism

BACKGROUND AND OBJECTIVES

Because subclinical thyroid dysfunction may be a risk factor for cardiovascular disease, we evaluated the atherosclerosis tendency in subclinical hypothyroid (SCH) patients.

PATIENTS AND METHODS

Fifty-three subclinical hypothyroid patients (serum thyrotropin [TSH] concentrations >4.12 mU/L) were compared with a control group of 50 euthyroid subjects whose age, sex and body mass indices were similar to the patient group. We tested whether serum TSH concentrations were correlated with plasma total homocysteine concentration (tHcy), low-density lipoprotein cholesterol (LDL-C), very low-density lipoprotein cholesterol (VLDL-C), high-density lipoprotein cholesterol (HDL-C), total cholesterol (TC) and triglycerides (TG).

RESULTS

There was a significant statistical difference between the patient and control groups for normal free T4 (1.02+/-0.17 vs. 0.86+/-0.13, P<.001), TSH (1.64+/-1.02 vs. 6.62+/-2.61, P<.001), TC (185+/-39 vs. 206 +/- 42, P=.01), TG (103+/-54 vs. 132+/-85, P=.04), LDL-C (114+/-33 vs. 127+/-36, P=.04), and TC/HDL-C (3.81+/-106 vs. 4.19+/-1.02, P=.04), respectively. No statistically significant difference was found between the two groups for HDL-C, VLDLC, LDL-C/HDL-C, and tHcy. Serum TSH was significantly correlated with plasma tHcy (r=0.55; P=.001), TC (r=0.52; P=.001), LDL-C (r=0.49; P=.001), TC/HDL-C (r=0.38; P=.002) and LDL-C/HDL-C (r=0.36; P=.004) across all participants.

CONCLUSION

Our study suggests that the atherogenicity of SCH is not mediated by hyperhomocysteinemia. Associated hyperlipidemia may explain the observed increased risk of coronary artery disease in patients with SCH.

Genetics and heritability of coronary artery disease and myocardial infarction

A positive family history is frequently reported by patients with coronary artery disease (CAD) or myocardial infarction. For risk stratification, it is crucial to distinguish between accidental reoccurrence of sporadic cases and cases with a true heritable component of the conditions. A familial predisposition is assumed when a myocardial infarction is diagnosed by a male first degree relative before the 55th year of life or a female first degree relative before the 65th year of life. The current manuscript reviews major studies from which a familial risk of CAD or myocardial infarction can be inferred. Moreover, a brief overview summarizes the current results of molecular genetic research on chromosomal loci and genes relevant for CAD and myocardial infarction.