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Background: Common diseases such as coronary heart disease (CHD) are complex in etiology. The interaction of genetic susceptibility with lifestyle factors may play a prominent role. However, gene-lifestyle interactions for CHD have been difficult to identify. Here, we investigate interaction of smoking behavior, a potent lifestyle factor, with genotypes that have been shown to associate with CHD risk., Methods: We analyzed data on 60 919 CHD cases and 80 243 controls from 29 studies for gene-smoking interactions for genetic variants at 45 loci previously reported to be associated with CHD risk. We also studied 5 loci associated with smoking behavior. Study-specific gene-smoking interaction effects were calculated and pooled using fixed-effects meta-analyses. Interaction analyses were declared to be significant at a P value of <1.0×10 -3 (Bonferroni correction for 50 tests)., Results: We identified novel gene-smoking interaction for a variant upstream of the ADAMTS7 gene. Every T allele of rs7178051 was associated with lower CHD risk by 12% in never-smokers ( P =1.3×10 -16 ) in comparison with 5% in ever-smokers ( P =2.5×10 -4 ), translating to a 60% loss of CHD protection conferred by this allelic variation in people who smoked tobacco (interaction P value=8.7×10 -5 ). The protective T allele at rs7178051 was also associated with reduced ADAMTS7 expression in human aortic endothelial cells and lymphoblastoid cell lines. Exposure of human coronary artery smooth muscle cells to cigarette smoke extract led to induction of ADAMTS7. CONCLUSIONS: Allelic variation at rs7178051 that associates with reduced ADAMTS7 expression confers stronger CHD protection in never-smokers than in ever-smokers. Increased vascular ADAMTS7 expression may contribute to the loss of CHD protection in smokers., (© 2017 American Heart Association, Inc.)

Low-frequency coding DNA sequence variants in the proprotein convertase subtilisin/kexin type 9 gene (PCSK9) lower plasma low-density lipoprotein cholesterol (LDL-C), protect against risk of coronary heart disease (CHD), and have prompted the development of a new class of therapeutics. It is uncertain whether the PCSK9 example represents a paradigm or an isolated exception. We used the "Exome Array" to genotype >200,000 low-frequency and rare coding sequence variants across the genome in 56,538 individuals (42,208 European ancestry [EA] and 14,330 African ancestry [AA]) and tested these variants for association with LDL-C, high-density lipoprotein cholesterol (HDL-C), and triglycerides. Although we did not identify new genes associated with LDL-C, we did identify four low-frequency (frequencies between 0.1% and 2%) variants (ANGPTL8 rs145464906 [c.361C>T; p.Gln121*], PAFAH1B2 rs186808413 [c.482C>T; p.Ser161Leu], COL18A1 rs114139997 [c.331G>A; p.Gly111Arg], and PCSK7 rs142953140 [c.1511G>A; p.Arg504His]) with large effects on HDL-C and/or triglycerides. None of these four variants was associated with risk for CHD, suggesting that examples of low-frequency coding variants with robust effects on both lipids and CHD will be limited., (Copyright © 2014 The American Society of Human Genetics. Published by Elsevier Inc. All rights reserved.)

Background: Red cell distribution width (RDW) is associated with morbidity and mortality in coronary artery disease (CAD), but the connection of RDW with chronic inflammation is equivocal., Methods: In 1,489 patients with CAD and 8.4-15.2 years of follow-up all-cause mortality and RDW were studied using Cox regression. RDW and its associations with inflammation, liver function, renal function, and body mass were assessed. A population of 449 normal (No-CAD) patients also was evaluated., Results: RDW predicted all-cause mortality in a step-wise manner (HR=1.37 per quintile; 95% CI=1.29, 1.46; p-trend<0.001). A significant but meaningless correlation between RDW and high-sensitivity C-reactive protein (hsCRP) was identified (r=0.181; p<0.001). With full adjustment, RDW remained significant (p-trend<0.001) and the strongest predictor of mortality among all factors included in the model. RDW also strongly predicted all-cause mortality in the normal control population (HR=1.33 per quintile, CI=1.15, 1.55; p-trend<0.001), but hsCRP did not predict mortality among normal controls., Conclusions: RDW was associated with mortality in patients with CAD and may provide clinically useful prognostication. Although RDW was correlated with hsCRP, they were independent predictors of mortality. RDW has been incorporated into risk prediction tool using data from basic chemistries available at: http://intermountainhealthcare.org/IMRS., (Copyright © 2011 Elsevier B.V. All rights reserved.)

Background: Hypertension affects 1 billion individuals worldwide and is an independent risk factor for death after acute coronary syndromes (ACS)., Methods: We examined the prevalence and medical treatment of hypertension among 15,904 ACS patients randomized in the SYMPHONY and 2nd SYMPHONY trials. Analyses were performed overall and according to sex for the United States and across international practice. Multivariable models identified factors associated with use of antihypertensive medication classes and examined the association of hypertension and sex with mortality., Results: In the United States, hypertension was more prevalent in women than in men, overall (63% vs 50%) and within every decile of age. Hypertensive women more often received calcium-channel blockers (35% vs 30%) and diuretics (33% vs 19%) and less often received beta-blockers (51% vs 57%). Angiotensin-converting enzyme inhibitor use was similar (35% vs 34%). Women received multiple agents more frequently than did men: 2 agents, 35% vs 30%; > or = 3 agents, 16% vs 13%. Female sex independently predicted drug-class use only for diuretics. Mortality was higher in hypertensive women than in hypertensive men; after multivariable adjustment, mortality was similar without evidence of a differential association between hypertension and mortality according to sex. Although there was international variation in the use of individual classes of agents, the overall findings by sex were similar across regions., Conclusion: Hypertension is more prevalent in women than in men with ACS, and its medical management varies by sex, but its association with mortality is similar. Opportunities exist to improve medical therapy and outcomes in women with hypertension.

Background: Recent trials reveal no benefit and possible harm from chronic hormone replacement therapy (HRT). Less is known about intermediate-term outcomes associated with HRT use in the setting of acute coronary syndromes (ACS)., Methods: To examine the prevalence of HRT use and relationships with intermediate-term outcomes among women with ACS, we classified as HRT users or nonusers 4029 postmenopausal women (age > 50 years or postmenopausal by case report form) randomized in the Sibrafiban versus Aspirin to Yield Maximum Protection from Ischemic Heart Events Post-Acute Coronary Syndromes (SYMPHONY) and 2nd SYMPHONY trials. Outcomes included 90-day and 1-year death and 90-day stroke, death, or myocardial infarction (MI); death, MI, or stroke; and death, MI, or severe recurrent ischemia (SRI)., Results: HRT use was 13% overall and varied by region (Asia, 0%; Eastern Europe, 0.2%; Latin America, 0.8%; Western Europe, 4%; Australia/New Zealand, 12%; Canada, 14%; United States, 24%); estrogen-only regimens were most common (90%). HRT users were younger, had higher estimated creatinine clearance, more frequently were smokers and had prior revascularization, but less frequently had diabetes, prior angina, or heart failure. Unadjusted 90-day and 1-year mortality rates were lower among HRT users (hazard ratios [95% CI] 0.48 [0.23-0.98] and 0.35 [0.18-0.68], respectively) but after multivariable adjustment, were not significantly different. Ninety-day stroke and composite end points did not differ between HRT users and nonusers., Conclusions: HRT use (predominantly estrogen-only) was low among patients with ACS but varied by region and was not associated with improved intermediate-term outcomes. These results are consistent with the absence of benefit from HRT use (combination or estrogen only) in previous studies in more stable populations.

Objective: Obesity and metabolic syndrome are associated with major adverse cardiovascular events (MACE). However, whether distinct metabolic phenotypes differ in risk for coronary artery disease (CAD) and MACE is unknown. We sought to determine the association of distinct metabolic phenotypes with CAD and MACE.Research Design and Methods: We included patients from the Prospective Multicenter Imaging Study for Evaluation of Chest Pain (PROMISE) who underwent coronary computed tomography (CT) angiography. Obesity was defined as a BMI ≥30 kg/m2 and metabolically healthy as less than or equal to one metabolic syndrome component except diabetes, distinguishing four metabolic phenotypes: metabolically healthy/unhealthy and nonobese/obese (MHN, MHO, MUN, and MUO). Differences in severe calcification (coronary artery calcification [CAC] ≥400), severe CAD (≥70% stenosis), high-risk plaque (HRP), and MACE were assessed using adjusted logistic and Cox regression models.Results: Of 4,381 patients (48.4% male, 60.5 ± 8.1 years of age), 49.4% were metabolically healthy (30.7% MHN and 18.7% MHO) and 50.6% unhealthy (22.3% MUN and 28.4% MUO). MHO had similar coronary CT findings as compared with MHN (severe CAC/CAD and HRP; P > 0.36 for all). Among metabolically unhealthy patients, those with obesity had similar CT findings as compared with nonobese (P > 0.10 for all). However, both MUN and MUO had unfavorable CAD characteristics as compared with MHN (P ≤ 0.017 for all). A total of 130 events occurred during follow-up (median 26 months). Compared with MHN, MUN (hazard ratio [HR] 1.61 [95% CI 1.02-2.53]) but not MHO (HR 1.06 [0.62-1.82]) or MUO (HR 1.06 [0.66-1.72]) had higher risk for MACE.Conclusions: In patients with stable chest pain, four metabolic phenotypes exhibit distinctly different CAD characteristics and risk for MACE. Individuals who are metabolically unhealthy despite not being obese were at highest risk in our cohort. [ABSTRACT FROM AUTHOR]

In this issue, in the largest and most comprehensive such study in LQTS, Lahrouchi et al[3] pool 1656 LQTS cases, finding that common variants are associated with LQTS and may be a distinct genetic subtype of LQTS. These interesting results suggest that a significant proportion of LQTS disease burden is explained by common variation, and that a higher burden of common QT interval-associated variants increases risk of overt LQTS in genotype-negative patients. Last, the authors perform a discovery GWAS comparing the 1656 LQTS cases with 9890 non-LQTS controls, identifying common variation in the I NOS1AP, KCNQ1 i , and I KLF12 i genes as associated with LQTS. [Extracted from the article]

Survival bias may unduly impact genetic association with complex diseases; gene-specific survival effects may further complicate such investigations. Coronary artery disease (CAD) is a complex phenotype for which little is understood about gene-specific survival effects; yet, such information can offer insight into refining genetic associations, improving replications, and can provide candidate genes for both mortality risk and improved survivorship in CAD. Building on our previous work, the purpose of this current study was to: evaluate LSAMP SNP-specific hazards for all-cause mortality post-catheterization in a larger cohort of our CAD cases; and, perform additional replication in an independent dataset. We examined two LSAMP SNPs—rs1462845 and rs6788787—using CAD case-only Cox proportional hazards regression for additive genetic effects, censored on time-to-all-cause mortality or last follow-up among Caucasian subjects from the Catheterization Genetics Study (CATHGEN; n = 2,224) and the Intermountain Heart Collaborative Study (IMHC; n = 3,008). Only after controlling for age, sex, body mass index, histories of smoking, type 2 diabetes, hyperlipidemia and hypertension (HR = 1.11, 95%CI = 1.01–1.22, p = 0.032), rs1462845 conferred significantly increased hazards of all-cause mortality among CAD cases. Even after controlling for multiple covariates, but in only the primary cohort, rs6788787 conferred significantly improved survival (HR = 0.80, 95% CI = 0.69–0.92, p = 0.002). Post-hoc analyses further stratifying by sex and disease severity revealed replicated effects for rs1462845: even after adjusting for aforementioned covariates and coronary interventional procedures, males with severe burden of CAD had significantly amplified hazards of death with the minor variant of rs1462845 in both cohorts (HR = 1.29, 95% CI = 1.08–1.55, p = 0.00456; replication HR = 1.25, 95% CI = 1.05–1.49, p = 0.013). Kaplan-Meier curves revealed unique cohort-specific genotype effects on survival. Additional analyses demonstrated that the homozygous risk genotype (‘A/A’) fully explained the increased hazard in both cohorts. None of the post-hoc analyses in control subjects were significant for any model. This suggests that genetic effects of rs1462845 on survival are unique to CAD presence. This represents formal, replicated evidence of genetic contribution of rs1462845 to increased risk for all-cause mortality; the contribution is unique to CAD case status and specific to males with severe burden of CAD. [ABSTRACT FROM AUTHOR]

Previously we have shown that a functional nonsynonymous single nucleotide polymorphism (rs6318) of the 5HTR2C gene located on the X-chromosome is associated with hypothalamic-pituitary-adrenal axis response to a stress recall task, and with endophenotypes associated with cardiovascular disease (CVD). These findings suggest that individuals carrying the rs6318 Ser23 C allele will be at higher risk for CVD compared to Cys23 G allele carriers. The present study examined allelic variation in rs6318 as a predictor of coronary artery disease (CAD) severity and a composite endpoint of all-cause mortality or myocardial infarction (MI) among Caucasian participants consecutively recruited through the cardiac catheterization laboratory at Duke University Hospital (Durham, NC) as part of the CATHGEN biorepository. Study population consisted of 6,126 Caucasian participants (4,036 [65.9%] males and 2,090 [34.1%] females). A total of 1,769 events occurred (1,544 deaths and 225 MIs; median follow-up time =  5.3 years, interquartile range  = 3.3–8.2). Unadjusted Cox time-to-event regression models showed, compared to Cys23 G carriers, males hemizygous for Ser23 C and females homozygous for Ser23C were at increased risk for the composite endpoint of all-cause death or MI: Hazard Ratio (HR)  = 1.47, 95% confidence interval (CI)  = 1.17, 1.84, p  = .0008. Adjusting for age, rs6318 genotype was not related to body mass index, diabetes, hypertension, dyslipidemia, smoking history, number of diseased coronary arteries, or left ventricular ejection fraction in either males or females. After adjustment for these covariates the estimate for the two Ser23 C groups was modestly attenuated, but remained statistically significant: HR  = 1.38, 95% CI = 1.10, 1.73, p = .005. These findings suggest that this functional polymorphism of the 5HTR2C gene is associated with increased risk for CVD mortality and morbidity, but this association is apparently not explained by the association of rs6318 with traditional risk factors or conventional markers of atherosclerotic disease. [ABSTRACT FROM AUTHOR]

We performed a gene–smoking interaction analysis using families from an early-onset coronary artery disease cohort (GENECARD). This analysis was focused on validating and expanding results from previous studies implicating single nucleotide polymorphisms (SNPs) on chromosome 3 in smoking-mediated coronary artery disease. We analyzed 430 SNPs on chromosome 3 and identified 16 SNPs that showed a gene–smoking interaction at P < 0.05 using association in the presence of linkage—ordered subset analysis, a method that uses permutations of the data to empirically estimate the strength of the association signal. Seven of the 16 SNPs were in the Rho-GTPase pathway indicating a 1.87-fold enrichment for this pathway. A meta-analysis of gene–smoking interactions in three independent studies revealed that rs9289231 in KALRN had a Fisher’s combined P value of 0.0017 for the interaction with smoking. In a gene-based meta-analysis KALRN had a P value of 0.026. Finally, a pathway-based analysis of the association results using WebGestalt revealed several enriched pathways including the regulation of the actin cytoskeleton pathway as defined by the Kyoto Encyclopedia of Genes and Genomes. [ABSTRACT FROM AUTHOR]

The article reports on a genome-wide association study for coronary artery disease (CAD) to identify a novel susceptibility locus in major histocompatibility complex. It is indicated that age-specific incidence of CAD is increased twofold in subjects with a family history of premature disease and family history contribution cannot be explained by CAD risk factors. It is accepted that atherosclerosis is driven by chronic inflammatory process in response to subendothelial lipoprotein retention.

The article presents a study on the association of a peripheral blood metabolic profile with coronary artery disease (CAD) and the risk of subsequent cardiovascular events. It describes the methodology and statistical analysis done to assesses the effect of metabolites in discriminating CAD and predict cardiovascular events. The study concluded that metabolite profiles are independently associated with CAD and risk of cardiovascular events.

The CATHGEN study reported associations of chromosome 3q13-21 genes ( KALRN, MYLK, CDGAP, and GATA2) with early-onset coronary artery disease (CAD). This study attempted to independently validate those associations. Eleven single nucleotide polymorphisms (SNPs) were examined (rs10934490, rs16834817, rs6810298, rs9289231, rs12637456, rs1444768, rs1444754, rs4234218, rs2335052, rs3803, rs2713604) in patients (N = 1618) from the Intermountain Heart Collaborative Study (IHCS). Given the higher smoking prevalence in CATHGEN than IHCS (41% vs. 11% in controls, 74% vs. 29% in cases), smoking stratification and genotype-smoking interactions were evaluated. Suggestive association was found for GATA2 (rs2713604, p = 0.057, OR = 1.2). Among smokers, associations were found in CDGAP (rs10934490, p = 0.019, OR = 1.6) and KALRN (rs12637456, p = 0.011, OR = 2.0) and suggestive association was found in MYLK (rs16834871, p = 0.051, OR = 1.8, adjusting for gender). No SNP association was found among non-smokers, but smoking/SNP interactions were detected for CDGAP (rs10934491, p = 0.017) and KALRN (rs12637456, p = 0.010). Similar differences in SNP effects by smoking status were observed on re-analysis of CATHGEN. CAD associations were suggestive for GATA2 and among smokers significant post hoc associations were found in KALRN, MYLK, and CDGAP. Genetic risk conferred by some of these genes may be modified by smoking. Future CAD association studies of these and other genes should evaluate effect modification by smoking. [ABSTRACT FROM AUTHOR]

Background: We previously identified a 40 Mb region of linkage on chromosome 1q in our early onset coronary artery disease (CAD) genome-wide linkage scan (GENECARD) with modest evidence for linkage (n = 420, LOD 0.95). When the data are stratified by acute coronary syndrome (ACS), this modest maximum in the overall group became a well-defined LOD peak (maximum LOD of 2.17, D1S1589/D1S518). This peak overlaps a recently identified inflammatory biomarker (MCP-1) linkage region from the Framingham Heart Study (maximum LOD of 4.27, D1S1589) and a region of linkage to metabolic syndrome from the IRAS study (maximum LOD of 2.59, D1S1589/D1S518). The overlap of genetic screens in independent data sets provides evidence for the existence of a gene or genes for CAD in this region. Methods: A peak-wide association screen (457 SNPs) was conducted of a region 1 LOD score down from the peak marker (168-198 Mb) in a linkage peak for acute coronary syndrome (ACS) on chromosome 1, within a family-based early onset coronary artery disease (CAD) sample (GENECARD). Results: Polymorphisms were identified within the 'family with sequence similarity 5, member C' gene (FAM5C) that show genetic linkage to and are associated with myocardial infarction (MI) in GENECARD. The association was confirmed in an independent CAD case-control sample (CATHGEN) and strong association with MI was identified with single nucleotide polymorphisms (SNPs) in the 3' end of FAM5C. FAM5C genotypes were also correlated with expression of the gene in human aorta. Expression levels of FAM5C decreased with increasing passage of proliferating aortic smooth muscle cells (SMC) suggesting a role for this molecule in smooth muscle cell proliferation and senescence. Conclusion: These data implicate FAM5C alleles in the risk of myocardial infarction and suggest further functional studies of FAM5C are required to identify the gene's contribution to atherosclerosis. [ABSTRACT FROM AUTHOR]

The transcription factor GATA2 plays an essential role in the establishment and maintenance of adult hematopoiesis. It is expressed in hematopoietic stem cells, as well as the cells that make up the aortic vasculature, namely aortic endothelial cells and smooth muscle cells. We have shown that GATA2 expression is predictive of location within the thoracic aorta; location is suggested to be a surrogate for disease susceptibility. The GATA2 gene maps beneath the Chromosome 3q linkage peak from our family-based sample set (GENECARD) study of early-onset coronary artery disease. Given these observations, we investigated the relationship of several known and novel polymorphisms within GATA2 to coronary artery disease. We identified five single nucleotide polymorphisms that were significantly associated with early-onset coronary artery disease in GENECARD. These results were validated by identifying significant association of two of these single nucleotide polymorphisms in an independent case-control sample set that was phenotypically similar to the GENECARD families. These observations identify GATA2 as a novel susceptibility gene for coronary artery disease and suggest that the study of this transcription factor and its downstream targets may uncover a regulatory network important for coronary artery disease inheritance. [ABSTRACT FROM AUTHOR]

A susceptibility locus for coronary artery disease (CAD) has been mapped to chromosome 3q13-21 in a linkage study of early-onset CAD. We completed an association-mapping study across the 1-LOD-unit-down supporting interval, using two independent white case-control data sets (CATHGEN, initial and validation) to evaluate association under the peak. Single-nucleotide polymorphisms (SNPs) evenly spaced at 100-kb intervals were screened in the initial data set (N = 468). Promising SNPs (P < .1) were then examined in the validation data set (N = 514). Significant findings (P <.05) in the combined initial and validation data sets were further evaluated in multiple independent data sets, including a family-based data set (N = 2,954), an African American case-control data set (N = 190), and an additional white control data set (N = 255). The association between genotype and aortic atherosclerosis was examined in 145 human aortas. The peakwide survey found evidence of association in SNPs from multiple genes. The strongest associations were found in three SNPs from the kalirin (KALRN) gene, especially in patients with early-onset CAD (P = .00001-00028 in the combined CATHGEN data sets). In-depth investigation of the gene found that an intronic SNP, rs9289231, was associated with early-onset CAD in all white data sets examined (P < .05). In the joint analysis of all white early-onset CAD cases (N = 332) and controls (N = 546), rs9289231 was highly significant (P = .00008), with an odds-ratio estimate of 2.1. Furthermore, the risk allele of this SNP was associated with atherosclerosis burden (P = .03) in 145 human aortas. KALRN is a protein with many functions, including the inhibition of inducible nitric oxide synthase and guanine-exchange-factor activity. KALRN and two other associated genes identified in this study (CDGAP and MYLK) belong to the Rho GTPase-signaling pathway. Our data suggest the importance of the KALRN gene and the Rho GTPase-signaling pathway in the pathogenesis of CAD. [ABSTRACT FROM AUTHOR]

Background: Familial combined hypolipidemia, a Mendelian condition characterized by substantial reductions in all 3 major lipid fractions, is caused by mutations that inactivate the gene angiopoietin-like 3 (ANGPTL3). Whether ANGPTL3 deficiency reduces risk of coronary artery disease (CAD) is unknown.Objectives: The study goal was to leverage 3 distinct lines of evidence-a family that included individuals with complete (compound heterozygote) ANGPTL3 deficiency, a population based-study of humans with partial (heterozygote) ANGPTL3 deficiency, and biomarker levels in patients with myocardial infarction (MI)-to test whether ANGPTL3 deficiency is associated with lower risk for CAD.Methods: We assessed coronary atherosclerotic burden in 3 individuals with complete ANGPTL3 deficiency and 3 wild-type first-degree relatives using computed tomography angiography. In the population, ANGPTL3 loss-of-function (LOF) mutations were ascertained in up to 21,980 people with CAD and 158,200 control subjects. LOF mutations were defined as nonsense, frameshift, and splice-site variants, along with missense variants resulting in <25% of wild-type ANGPTL3 activity in a mouse model. In a biomarker study, circulating ANGPTL3 concentration was measured in 1,493 people who presented with MI and 3,232 control subjects.Results: The 3 individuals with complete ANGPTL3 deficiency showed no evidence of coronary atherosclerotic plaque. ANGPTL3 gene sequencing demonstrated that approximately 1 in 309 people was a heterozygous carrier for an LOF mutation. Compared with those without mutation, heterozygous carriers of ANGPTL3 LOF mutations demonstrated a 17% reduction in circulating triglycerides and a 12% reduction in low-density lipoprotein cholesterol. Carrier status was associated with a 34% reduction in odds of CAD (odds ratio: 0.66; 95% confidence interval: 0.44 to 0.98; p = 0.04). Individuals in the lowest tertile of circulating ANGPTL3 concentrations, compared with the highest, had reduced odds of MI (adjusted odds ratio: 0.65; 95% confidence interval: 0.55 to 0.77; p < 0.001).Conclusions: ANGPTL3 deficiency is associated with protection from CAD. [ABSTRACT FROM AUTHOR]

Background: Although risk stratification is an important goal of cardiac noninvasive tests (NITs), few contemporary data exist on the prognostic value of different NITs according to patient sex.Objectives: The goal of this study was to compare the results and prognostic information derived from anatomic versus stress testing in stable men and women with suspected coronary artery disease.Methods: In 8,966 patients tested at randomization (4,500 to computed tomography angiography [CTA], 52% female; 4,466 to stress testing, 53% female), we assessed the relationship between sex and NIT results and between sex and a composite of death, myocardial infarction, or unstable angina hospitalization.Results: In women, a positive CTA (≥70% stenosis) was less likely than a positive stress test result (8% vs. 12%; adjusted odds ratio: 0.67). Compared with negative test results, a positive CTA was more strongly associated with subsequent clinical events than a positive stress test result (CTA-adjusted hazard ratio of 5.86 vs. stress-adjusted hazard ratio of 2.27; adjusted p = 0.028). Men were more likely to have a positive CTA than a positive stress test result (16% vs. 14%; adjusted odds ratio: 1.23). Compared with negative test results, a positive CTA was less strongly associated with subsequent clinical events than a positive stress test result in men, although this difference was not statistically significant (adjusted p = 0.168). Negative CTA and stress test results were equally likely to predict an event in both sexes. A significant interaction between sex, NIT type, and test result (p = 0.01) suggests that sex and NIT type jointly influence the relationship between test result and clinical events.Conclusions: The prognostic value of an NIT result varies according to test type and patient sex. Women seem to derive more prognostic information from a CTA, whereas men tend to derive similar prognostic value from both test types. [ABSTRACT FROM AUTHOR]

Abstract: Objective: To validate independent associations between branched-chain amino acids (BCAA) and other metabolites with coronary artery disease (CAD). Methods: We conducted mass-spectrometry-based profiling of 63 metabolites in fasting plasma from 1983 sequential patients undergoing cardiac catheterization. Significant CAD was defined as CADindex ≥ 32 (at least one vessel with ≥95% stenosis; N = 995) and no CAD as CADindex ≤ 23 and no previous cardiac events (N = 610). Individuals (N = 378) with CAD severity between these extremes were excluded. Principal components analysis (PCA) reduced large numbers of correlated metabolites into uncorrelated factors. Association between metabolite factors and significant CAD vs. no CAD was tested using logistic regression; and between metabolite factors and severity of CAD was tested using linear regression. Results: Of twelve PCA-derived metabolite factors, two were associated with CAD in multivariable models: factor 10, composed of BCAA (adjusted odds ratio, OR, 1.20; 95% CI 1.05–1.35, p = 0.005) and factor 7, composed of short-chain acylcarnitines, which include byproducts of BCAA metabolism (adjusted OR 1.30; 95% CI 1.14–1.48, p = 0.001). After adjustment for glycated albumin (marker of insulin resistance [IR]) both factors 7 (p = 0.0001) and 10 (p = 0.004) remained associated with CAD. Severity of CAD as a continuous variable (including patients with non-obstructive disease) was associated with metabolite factors 2, 3, 6, 7, 8 and 9; only factors 7 and 10 were associated in multivariable models. Conclusions: We validated the independent association of metabolites involved in BCAA metabolism with CAD extremes. These metabolites may be reporting on novel mechanisms of CAD pathogenesis that are independent of IR and diabetes. [Copyright &y& Elsevier]

Objectives: This study sought to ascertain the relationship of 9p21 locus with: 1) angiographic coronary artery disease (CAD) burden; and 2) myocardial infarction (MI) in individuals with underlying CAD. Background: Chromosome 9p21 variants have been robustly associated with coronary heart disease, but questions remain on the mechanism of risk, specifically whether the locus contributes to coronary atheroma burden or plaque instability. Methods: We established a collaboration of 21 studies consisting of 33,673 subjects with information on both CAD (clinical or angiographic) and MI status along with 9p21 genotype. Tabular data are provided for each cohort on the presence and burden of angiographic CAD, MI cases with underlying CAD, and the diabetic status of all subjects. Results: We first confirmed an association between 9p21 and CAD with angiographically defined cases and control subjects (pooled odds ratio [OR]: 1.31, 95% confidence interval [CI]: 1.20 to 1.43). Among subjects with angiographic CAD (n = 20,987), random-effects model identified an association with multivessel CAD, compared with those with single-vessel disease (OR: 1.10, 95% CI: 1.04 to 1.17)/copy of risk allele). Genotypic models showed an OR of 1.15, 95% CI: 1.04 to 1.26 for heterozygous carrier and OR: 1.23, 95% CI: 1.08 to 1.39 for homozygous carrier. Finally, there was no significant association between 9p21 and prevalent MI when both cases (n = 17,791) and control subjects (n = 15,882) had underlying CAD (OR: 0.99, 95% CI: 0.95 to 1.03)/risk allele. Conclusions: The 9p21 locus shows convincing association with greater burden of CAD but not with MI in the presence of underlying CAD. This adds further weight to the hypothesis that 9p21 locus primarily mediates an atherosclerotic phenotype. [Copyright &y& Elsevier]

Background: Genetic risk scores (GRS) composed of single nucleotide polymorphisms (SNPs) associated with coronary artery disease (CAD) have been shown to predict cardiovascular risk in primary and secondary prevention populations. We tested whether an expanded CAD-GRS predicted risk of recurrent coronary events in patients presenting with acute coronary syndrome (ACS). Methods: We genotyped 6,404 individuals from the genetics substudy of the IMPROVE-IT trial, which tested whether the addition of ezetimibe to statin therapy improves cardiovascular outcomes. We studied the association of an updated CAD-GRS that included 75 genetic variants, with a composite outcome of coronary heart disease death, myocardial infarction or urgent coronary revascularization, adjusting, importantly, for the clinical TIMI Risk Score for Secondary Prevention. Results: When divided into low (quintile 1), intermediate (quintiles 2-4) and high (quintile 5) genetic risk categories, a significant gradient in risk for recurrent cardiovascular events was observed such that, after adjusting for clinical risk factors, patients in the highest genetic risk category had a 44% greater risk compared to those in the lowest genetic risk category (P=0.0004) [Figure]. In terms of the benefit of ezetimibe vs. placebo, the hazard ratios and absolute risk reductions were 0.89 (95% CI 0.65-1.21) & 2.0%, 0.94 (95% CI 0.80-1.11) & 0.6% and 0.82 (95% CI 0.63-1.07) & 3.1% for the low, intermediate and high genetic risk categories, respectively. Conclusion: An expanded GRS composed of 75 CAD-associated SNPs identifies patients presenting with ACS who are at significantly increased risk of recurrent coronary events independent of clinical risk factors. Patients with the highest burden of genetic risk tended to derive the largest relative and absolute clinical benefit from ezetimibe therapy. [ABSTRACT FROM AUTHOR]