Cross-Sectional Gene-Smoking Interaction Analysis in Relation to Subclinical Atherosclerosis-Results From the IMPROVE Study.

BACKGROUND: Smoking is associated with carotid intima-media thickness (C-IMT). However, knowledge about how genetics may influence this association is limited. We aimed to perform nonhypothesis driven gene-smoking interaction analyses to identify potential genetic variants, among those included in immune and metabolic platforms, that may modify the effect of smoking on carotid intima-media thickness. METHODS: We used baseline data from 1551 men and 1700 women, aged 55 to 79, included in a European multi-center study. Carotid intima-media thickness maximum, the maximum of values measured at different locations of the carotid tree, was dichotomized with cut point values ≥75, respectively. Genetic data were retrieved through use of the Illumina Cardio-Metabo- and Immuno- Chips. Gene-smoking interactions were evaluated through calculations of Synergy index (S). After adjustments for multiple testing, P values of <2.4×10-7 for S were considered significant. The models were adjusted for age, sex, education, physical activity, type of diet, and population stratification. RESULTS: Our screening of 207 586 SNPs available for analysis, resulted in the identification of 47 significant gene-smoking synergistic interactions in relation to carotid intima-media thickness maximum. Among the significant SNPs, 28 were in protein coding genes, 2 in noncoding RNA and the remaining 17 in intergenic regions. CONCLUSIONS: Through nonhypothesis-driven analyses of gene-smoking interactions, several significant results were observed. These may stimulate further research on the role of specific genes in the process that determines the effect of smoking habits on the development of carotid atherosclerosis.

Associations of Polymorphisms in the Peroxisome Proliferator-Activated Receptor Gamma Coactivator-1 Alpha Gene With Subsequent Coronary Heart Disease: An Individual-Level Meta-Analysis.

Background: The knowledge of factors influencing disease progression in patients with established coronary heart disease (CHD) is still relatively limited. One potential pathway is related to peroxisome proliferator-activated receptor gamma coactivator-1 alpha (PPARGC1A), a transcription factor linked to energy metabolism which may play a role in the heart function. Thus, its associations with subsequent CHD events remain unclear. We aimed to investigate the effect of three different SNPs in the PPARGC1A gene on the risk of subsequent CHD in a population with established CHD. Methods: We employed an individual-level meta-analysis using 23 studies from the GENetIcs of sUbSequent Coronary Heart Disease (GENIUS-CHD) consortium, which included participants (n = 80,900) with either acute coronary syndrome, stable CHD, or a mixture of both at baseline. Three variants in the PPARGC1A gene (rs8192678, G482S; rs7672915, intron 2; and rs3755863, T528T) were tested for their associations with subsequent events during the follow-up using a Cox proportional hazards model adjusted for age and sex. The primary outcome was subsequent CHD death or myocardial infarction (CHD death/myocardial infarction). Stratified analyses of the participant or study characteristics as well as additional analyses for secondary outcomes of specific cardiovascular disease diagnoses and all-cause death were also performed. Results: Meta-analysis revealed no significant association between any of the three variants in the PPARGC1A gene and the primary outcome of CHD death/myocardial infarction among those with established CHD at baseline: rs8192678, hazard ratio (HR): 1.01, 95% confidence interval (CI) 0.98-1.05 and rs7672915, HR: 0.97, 95% CI 0.94-1.00; rs3755863, HR: 1.02, 95% CI 0.99-1.06. Similarly, no significant associations were observed for any of the secondary outcomes. The results from stratified analyses showed null results, except for significant inverse associations between rs7672915 (intron 2) and the primary outcome among 1) individuals aged ≥65, 2) individuals with renal impairment, and 3) antiplatelet users. Conclusion: We found no clear associations between polymorphisms in the PPARGC1A gene and subsequent CHD events in patients with established CHD at baseline.

Intake of food rich in saturated fat in relation to subclinical atherosclerosis and potential modulating effects from single genetic variants.

The relationship between intake of saturated fats and subclinical atherosclerosis, as well as the possible influence of genetic variants, is poorly understood and investigated. We aimed to investigate this relationship, with a hypothesis that it would be positive, and to explore whether genetics may modulate it, using data from a European cohort including 3,407 participants aged 54-79 at high risk of cardiovascular disease. Subclinical atherosclerosis was assessed by carotid intima-media thickness (C-IMT), measured at baseline and after 30 months. Logistic regression (OR; 95% CI) was employed to assess the association between high intake of food rich in saturated fat (vs. low) and: (1) the mean and the maximum values of C-IMT in the whole carotid artery (C-IMTmean, C-IMTmax), in the bifurcation (Bif-), the common (CC-) and internal (ICA-) carotid arteries at baseline (binary, cut-point ≥ 75th), and (2) C-IMT progression (binary, cut-point > zero). For the genetic-diet interaction analyses, we considered 100,350 genetic variants. We defined interaction as departure from additivity of effects. After age- and sex-adjustment, high intake of saturated fat was associated with increased C-IMTmean (OR:1.27;1.06-1.47), CC-IMTmean (OR:1.22;1.04-1.44) and ICA-IMTmean (OR:1.26;1.07-1.48). However, in multivariate analysis results were no longer significant. No clear associations were observed between high intake of saturated fat and risk of atherosclerotic progression. There was no evidence of interactions between high intake of saturated fat and any of the genetic variants considered, after multiple testing corrections. High intake of saturated fats was not independently associated with subclinical atherosclerosis. Moreover, we did not identify any significant genetic-dietary fat interactions in relation to risk of subclinical atherosclerosis.

Acyl-CoA: cholesterol acyltransferases-2 gene polymorphism is associated with increased susceptibility to coronary artery disease in Uygur population in Xinjiang, China.

BACKGROUND: Acyl-CoA: cholesterol acyltransferases (ACAT) is the only enzyme that catalyzes the synthesis of cholesterol esters (CE) from free cholesterol and long-chain fatty acyl-CoA and plays a critical role in cellular cholesterol homeostasis. In the present study, our primary objective was to explore whether the single-nucleotide polymorphisms (SNPs) in ACAT-2 gene were associated with coronary artery disease (CAD) in Uygur subjects, in Xinjiang, China. METHODS: We designed a case-control study including 516 CAD patients and 318 age- and sex-matched control subjects. Using the improved multiplex ligation detection reaction (iMLDR) method, we genotyped two SNPs (rs28765985 and rs7308390) of ACAT-2 gene in all subjects. RESULTS: We found that the genotypes, the dominant model (CC + CT vs TT) and over-dominant model (CT vs CC + TT) of rs28765985 were significantly different between CAD patients and the controls (P=0.027, P=0.012 and P=0.035, respectively). The rs28765985 C allele was associated with a significantly elevated CAD risk [CC/CT vs TT: odds ratio (OR) = 1.48, 95% confidence interval (CI) = 1.02-2.16, P=0.04] after adjustment for confounders. The TC and LDL-C levels were significantly higher in rs28765985 CC/CT genotypes than that in TT genotypes (P<0.05). CONCLUSIONS: Rs28765985 of ACAT-2 gene are associated with CAD in Uygur subjects. Subjects with CC/CT genotype or C allele of rs28765985 were associated with an increased risk of CAD.

Sex-Related Differences Between Patients With Symptomatic Acute Aortic Dissection.

We designed a retrospective cohort study to assess sex-related differences in clinical manifestations, incidence, and outcomes of patients with symptomatic acute aortic dissection (AAD). We collected clinical data from 2010 to 2015 of 400 patients with AAD. Patients' clinical characteristics, treatment, and outcomes were analyzed as a function of sex. Among 400 patients with AAD, the ratio of men to women was 3.18:1; the incidence of atherosclerosis was higher in women (P = 0.02). Dysphoria (P = 0.01), focal neurological deficits (P = 0.04), and pulse deficits (P = 0.03) were more frequent in men. Imaging findings revealed that pleural effusion (P < 0.01), celiac trunk involvement (P < 0.01), and superior mesenteric artery involvement (P = 0.02) were more frequent in men. Dissection-related pneumonia (P = 0.02), pulmonary atelectasis (P = 0.01), aortic intramural hematoma (P < 0.01), ischemic electrocardiographic changes (P = 0.03), and in-hospital complications such as myocardial ischemia (P = 0.03), hypoxemia (P < 0.01), cardiac tamponade (P = 0.01) occurred more frequently in women. Women with type A dissection had higher in-hospital mortality than men (P < 0.01). The presentation of AAD varies with a patient's sex. Women with AAD had clinical features different from men as follows: higher age of onset, more frequent inpatient complications, and higher in-hospital mortality. These findings may lead to a better understanding of aortic dissection in women that will improve their outcomes.

Association between ErbB3 genetic polymorphisms and coronary artery disease in the Han and Uyghur populations of China.

BACKGROUND: ErbB3 is a member of the epidermal growth factor receptor (EGFR/ERBB) family of receptor tyrosine kinases. Recent research has shown that amplification of this gene is related to prostate, bladder and breast cancers, as well as low-density lipoprotein cholesterol (LDL-C) metabolism. LDL-C plays a considerable role in the development of cardiovascular disease. Thus, the present study assessed the association between human ErbB3 gene polymorphisms and coronary artery disease (CAD) in Han and Uygur populationsin China. METHODS: We performed two independent case-control studies with a Han population (339 CAD patients and 395 control subjects) and a Uygur population (306 CAD patients and 325 control subjects). All of the CAD patients and controls were genotyped for the same three single nucleotide polymorphisms (rs877636, rs705708, and rs10783779) in the ErbB3 gene by real-time PCR. RESULTS: In the Han population, rs877636 polymorphisms were associated with CAD on the basis of the genotypes, dominant model, additive model, and allele frequency (for genotypes: P = 0.008; for dominant model: P = 0.003; for additive model: P = 0.004; for allele: P = 0.008), and these significant difference was retained (all P < 0.05) after adjusting for the major confounding factors. CONCLUSION: The CT genotype and C allele of rs877636 in the ErbB3 gene could be a genetic marker of CAD risk for the Han population in China.