Genome-Wide Association Study Identifies a Functional SIDT2 Variant Associated With HDL-C (High-Density Lipoprotein Cholesterol) Levels and Premature Coronary Artery Disease.

Objective: Low HDL-C (high-density lipoprotein cholesterol) is the most frequent dyslipidemia in Mexicans, but few studies have examined the underlying genetic basis. Our purpose was to identify genetic variants associated with HDL-C levels and cardiovascular risk in the Mexican population. Approach and Results: A genome-wide association studies for HDL-C levels in 2335 Mexicans, identified four loci associated with genome-wide significance: CETP, ABCA1, LIPC, and SIDT2. The SIDT2 missense Val636Ile variant was associated with HDL-C levels and was replicated in 3 independent cohorts (P=5.9×10−18 in the conjoint analysis). The SIDT2/Val636Ile variant is more frequent in Native American and derived populations than in other ethnic groups. This variant was also associated with increased ApoA1 and glycerophospholipid serum levels, decreased LDL-C (low-density lipoprotein cholesterol) and ApoB levels, and a lower risk of premature CAD. Because SIDT2 was previously identified as a protein involved in sterol transport, we tested whether the SIDT2/Ile636 protein affected this function using an in vitro site-directed mutagenesis approach. The SIDT2/Ile636 protein showed increased uptake of the cholesterol analog dehydroergosterol, suggesting this variant affects function. Finally, liver transcriptome data from humans and the Hybrid Mouse Diversity Panel are consistent with the involvement of SIDT2 in lipid and lipoprotein metabolism. Conclusions: This is the first genome-wide association study for HDL-C levels seeking associations with coronary artery disease in the Mexican population. Our findings provide new insight into the genetic architecture of HDL-C and highlight SIDT2 as a new player in cholesterol and lipoprotein metabolism in humans.

Participation of white adipose tissue dysfunction on circulating HDL cholesterol and HDL particle size in apparently healthy humans.

OBJECTIVE: To use the combined presence of the elevated insulin resistance index in adipose tissue (Adipo-IR) and low values of adiponectin as a marker of dysfunctional adipose tissue, and to analyze its possible association with low values of high-density lipoprotein cholesterol (HDL-C) and small size of HDL particles. RESEARCH DESIGN AND METHODS: The analysis included 253 subjects with functional adipose tissue and 253 with dysfunctional adipose tissue, considering similar gender, age, and body mass index (BMI). Adipo-IR was considered when index values (free fatty acids × insulin concentrations) were ≥75th percentile. Low levels of adiponectin were considered when concentration in serum was <25th percentile (determined by ELISA). HDL size was estimated by a quantitative validated equation. Small HDL size was considered when values were <25th percentile. RESULTS: When comparing subjects with functional adipose tissue with those of dysfunctional adipose tissue, the latter had a higher prevalence of low HDL-C (51.4% vs. 64.0%; p = 0.004) and small HDL (56.9% vs. 67.6%; p = 0.009). Multivariate analysis indicated that independently from other metabolic risk factors, dysfunction of adipose tissue is significantly associated with low HDL-C (OR: 1.624 [CI 95%: 1.100-2.397]) and small HDL (OR: 1.462 [CI 95%: 1.000-2.139]). Adding BMI, waist circumference, and subcutaneous or visceral adipose tissue did not modify the association. CONCLUSIONS: Dysfunction of adipose tissue is associated with a 65 and 50% higher probability of having low HDL-C and small HDL. Identification of dysfunctional adipose tissue could be a useful tool in the clinical setting to prevent the cardiometabolic risk independently from adiposity.

THE BRANCHED-CHAIN AMINO ACID TRANSAMINASE 1 -23C/G POLYMORPHISM CONFERS PROTECTION AGAINST ACUTE CORONARY SYNDROME.

BACKGROUND: Previous studies have shown an association between polymorphisms of the BAT1-NF-κB inhibitor-like-1 (NFKBIL1)-LTA genomic region and susceptibility to myocardial infarction and acute coronary syndrome (ACS). OBJECTIVE: The objective of the study was to study the role of three polymorphisms in the BAT1, NFKBIL1, and LTA genes on the susceptibility or protection against ACS; we included a group of cases-controls from Central Mexico. METHODS: The BAT1 rs2239527C/G, NFKBIL1 rs2071592T/A, and LTA rs1800683G/A polymorphisms were genotyped using a 5' TaqMan assay in a group of 625 patients with ACS and 617 healthy controls. RESULTS: Under a recessive model, the BAT1 -23C/G (rs2239527) polymorphism showed an association with protection against ACS (odds ratio = 0.56, and p-corrected = 0.019). In contrast, the genotype and allele frequencies of the NFKBIL1 rs2071592T/A and LTA rs1800683G/A polymorphisms were similar between ACS patients and controls and no association was identified. CONCLUSION: Our data suggest an association between the BAT1 -23C/G polymorphism and protection against ACS in Mexican patients.

Interleukin 27 polymorphisms, their association with insulin resistance and their contribution to subclinical atherosclerosis. The GEA Mexican study.

Our previous data suggest that the heterodimeric interleukin-27 (IL-27) could participate in the developing of insulin resistance (IR). Our aim was to assess the participation of IL-27p28 gene single nucleotide polymorphisms (SNPs) as markers for IR, subclinical atherosclerosis (SA) and cardiovascular risk factors in a Mexican population. Five IL-27p28 SNPs (rs153109, rs40837, rs17855750, rs26528 and rs181206) were genotyped in 856 individuals with IR and 644 participants without IR. Under inheritance models adjusted for confounding factors, the rs153109A (0.78[0.64-0.94] Padditive = 0.008, 0.58[0.41-0.82] Precessive = 0.002, 0.57[0.38-0.83] Pcodominant2 = 0.004), rs26528T (0.78[0.64-0.94] Padditive = 0.008, 0.61[0.43-0.88] Precessive = 0.007, 0.57[0.38-0.84] Pcodominant2 = 0.004) and rs40837A (0.76[0.63-0.92] Padditive = 0.004; 0.60[0.42-0.86] Precessive = 0.005; 0.54[0.37-0.80] Pcodominant2 = 0.002) alleles were related with a decreased risk of IR. Moreover, AAATA haplotype that contains the protector alleles was related with 17% lower risk of presenting IR (0.83 [0.71-0.98], P = 0.023). After adjusting for potential confounding variables, IL-27p28 SNPs were not associated with SA. However, some SNPs were associated with hypertension (rs26528 and rs40837) and increased total abdominal fat (rs17855750) in non-IR individuals, whereas in IR subjects we observed an association of rs26528 and rs40837 with hypoadiponectinemia. Our evidence suggests that rs40837A, rs153109A, and rs26528T alleles could be envisaged as protective markers for IR. Some polymorphisms showed an association with hypertension, low adiponectin levels, and increased total abdominal fat.

miR-196a2 (rs11614913) polymorphism is associated with coronary artery disease, but not with in-stent coronary restenosis.

OBJECTIVE: The aim of the study was to evaluate the association of miRNA-146a G/C (rs2910164), and miRNA-196a2 C/T (rs11614913) polymorphisms with the presence of coronary artery disease (CAD) and/or restenosis in patients with coronary stent. MATERIALS AND METHODS: The polymorphisms were determined in 218 patients with CAD who underwent coronary artery stenting (66 with restenosis and 152 without restenosis) and 611 healthy controls using 5' exonuclease TaqMan assays. RESULTS: The distribution of both polymorphisms was similar in patients with and without restenosis. However, when the whole group of patients (with and without restenosis) was compared to healthy controls, under co-dominant, dominant and additive genetic models, the T allele of the miRNA-196a2 C/T (rs11614913) polymorphism was associated with increased risk of CAD (OR = 2.18, Pco-dom = 0.006, OR = 1.86, Pdom = 0.002, and OR = 1.52, Padd = 0.002, respectively). All models were adjusted for age, type 2 diabetes mellitus, dyslipidemia, hypertension and smoking habit. The "GT" haplotype was associated with increased risk of developing CAD (OR = 1.36, P = 0.046). CONCLUSIONS: Our data suggests that the T allele of the miRNA-196a2 C/T (rs11614913) polymorphism is associated with the risk of developing CAD, but no association with restenosis was observed.

The rs10455872-G allele of the LPA gene is associated with high lipoprotein(a) levels and increased aortic valve calcium in a Mexican adult population.

Polymorphisms in the LPA gene have been associated with aortic valve calcification (AVC). There are wide differences in the allelic frequencies, Lp(a) levels, and the association with AVC among ethnic groups. The aim of this study was to determine the association of the LPA gene polymorphisms with Lp(a) levels and risk of developing AVC, in Mexican-Mestizos population. Six LPA polymorphisms (rs10455872, rs7765803, rs6907156, rs1321195, rs12212807 and rs6919346) were genotyped by TaqMan assays in 1,265 individuals without premature coronary artery disease. The presence of AVC was determined by computed tomography. The association of the LPA polymorphisms with AVC, Lp(a), and other cardiovascular risk factors (CVRF) was evaluated using logistic regression analysis. Compared to AA genotype, subjects with AG+GG genotypes had high prevalence of Lp(a) ≥ 30 mg/dL (7.1% vs. 23.7%, p<0.001) and AVC (19.0% vs. 29.4%, p=0.007). In a model adjusted for several CVRF, the LPA rs10455872-G allele was associated with high Lp(a) levels and AVC. Carriers of G allele had a high risk of Lp(a) ≥ 30 mg/dL (OR= 3.86, CI 95%: 2.2 - 6.7, p=0.001) and AVC (OR= 2.54, CI 95%: 1.56 - 4.14, p=0.001), independently of other CVRF. In this population, carriers of rs10455872-G allele had 3.86 and 2.54 higher risk of Lp(a) ≥ 30 mg/dL or presence of AVC, respectively.

The IL-10-1082 (rs1800896) G allele is associated with a decreased risk of developing premature coronary artery disease and some IL-10 polymorphisms were associated with clinical and metabolic parameters. The GEA study.

Interleukin 10 (IL-10) is an anti-inflammatory cytokine with a protective role in the formation and the development of the atherosclerotic plaque. The aim of the present study was to establish if IL-10 gene polymorphisms are associated with the development of premature coronary artery disease (pCAD) and cardiovascular risk factors in Mexican individuals. Three IL-10 gene polymorphisms [-592C/A (rs1800872), -819C/T (rs1800871), and -1082 A/G (rs1800896)] and IL-10 plasma levels were analyzed in 2266 individuals (1160 pCAD patients and 1106 healthy controls). Under recessive and co-dominant2 models, the -1082 A/G (rs1800896) G allele was associated with decreased risk of developing pCAD (OR = 0.572, Prec = 0.022 and OR = 0.567, Pcod2 = 0.023). In pCAD patients, the polymorphisms were associated with hyperinsulinemia, small and dense LDLs, hypertension, and diabetes mellitus. In the control group, the polymorphisms were associated with hypertension, hyperuricemia, and small and dense LDLs. pCAD patients have significantly higher IL-10 plasma levels than healthy controls [0.91 (0.55-1.67) pg/mL vs 0.45 (0.24-0.98) pg/mL, respectively, P < 0.0001]. Nevertheless, these levels were not associated with the genotypes analyzed in the present study. The results suggest that the IL-10-1082 A/G (rs1800896) G allele is associated with a decreased risk of developing pCAD. In patients and controls, the polymorphisms analyzed were associated with some cardiovascular risk factors. Although, in pCAD patients the IL-10 plasma levels were higher, they were not associated with the genotypes of the polymorphisms examined.

Vitamin D Deficiency is not Associated with Fatty Liver in a Mexican Population.

INTRODUCTION AND AIM: Association of vitamin D deficiency (VDD) with fatty liver (FL) disease is controversial. The purpose of this study was to analyze the association of VDD with FL. MATERIAL AND METHODS: Cross-sectional study. Data on cardiovascular risk factors, medications, alcohol intake, smoking, diet, and physical activity were obtained. Biochemical, anthropometric, and blood pressure variables were measured. The 25-hydroxyvitamin D (25(OH)D) was quantified through chemoluminescence. The presence of FL, defined as a liver/spleen attenuation index lower than 1.0, was identified through computed axial tomography (CAT). RESULTS: The study included 1,467 subjects (49.7% men) with a mean age of 53.3 ± 9.3 years and BMI of 28.3 ± 4.0 kg/m2. Only 11% had optimum values of vitamin D, and 25(OH)D concentration was lower in participants with FL. Multivariate logistic regression models, adjusted for age, gender, BMI, sampling season, glucose, total cholesterol, triglycerides, HOMA-IR, hs-CRP, ALT, AST, and elevated VAT, revealed an association between FL and vitamin D (VD) insufficiency (RM 1.61 [0.99-2.61]) and with VDD (RM 1.68 [1.02-2.77]); however, statistical significance was lost when including caloric consumption and physical activity in the model. CONCLUSIONS: In Mexican adults, deficient VD concentration and FL were not independently associated of caloric consumption and physical activity.

Raet1e Polymorphisms Are Associated with Increased Risk of Developing Premature Coronary Artery Disease and with Some Cardiometabolic Parameters: The GEA Mexican Study.

In an animal model, new evidence has been reported supporting the role of raet1e as an atherosclerosis-associated gene. Our objective was to establish if raet1e polymorphisms are associated with the risk of developing premature coronary artery disease (CAD) or with the presence of cardiometabolic parameters. After an informatic analysis, five polymorphisms were chosen and determined in 1158 patients with premature CAD and 1104 controls using 5' exonuclease TaqMan genotyping assays. Standardized questionnaires were applied to all participants to obtain family medical history, demographic information, history of nutritional habits, physical activity, alcohol consumption, and pharmacological treatment. The functional effect of the rs7756850 polymorphism was analyzed by luciferase assays. Under different models, adjusted by age, gender, body mass index, current smoking, and type 2 diabetes mellitus, the rs6925151 (OR = 1.250, p heterozygote = 0.026; OR = 1.268, p codominant1 = 0.034), rs9371533 (OR = 1.255, p heterozygote = 0.024), rs7756850 (OR = 1.274, p heterozygote = 0.016; OR = 1.294, p codominant1 = 0.031), and rs9383921 (OR = 1.232, p heterozygote = 0.037) polymorphisms were associated with increased risk of premature CAD. When compared to the rs7756850 G allele, the C allele showed a decreased luciferase activity. In premature CAD patients, associations with low levels of adiponectin, with a high presence of hypertension, and with high levels of gamma-glutamyltransferase and total cholesterol were observed. In healthy controls, associations with a decrease in LDL pattern B, aspartate aminotransaminase, and hypo-α-lipoproteinemia were detected. An association of the raet1e polymorphisms with an increased risk of developing premature CAD and with cardiometabolic parameters has been shown for the first time. In addition, the functional effect of the rs7756850 polymorphism was defined.

The UCP2 -866G/A, Ala55Val and UCP3 -55C/T polymorphisms are associated with premature coronary artery disease and cardiovascular risk factors in Mexican population.

We examined the role of UCP gene polymorphisms as susceptibility markers for premature coronary artery disease (pCAD). The UCP2 Ala55Val (C/T rs660339), UCP2 -866G/A (rs659366), and UCP3 -55C/T (rs1800849) polymorphisms were genotyped in 948 patients with pCAD, and 763 controls. The distribution of the UCP2 A55V (C/T rs660339) and UCP3 -55 (rs1800849) was similar in patients and controls. However, under a recessive model, the UCP2 -866 (rs659366) A allele was associated with increased risk of developing pCAD (OR = 1.43, Pc = 0.003). On the other hand, patients with pCAD and UCP2 A55V (rs660339) TT showed high levels of visceral abdominal fat (VAF) (Pc = 0.002), low levels of subcutaneous abdominal fat (SAF) (Pc = 0.001) and high VAT/SAT ratio (Pc < 0.001). Also, patients with UCP2 -866 (rs659366) AA showed increased levels of VAF (Pc = 0.003), low levels of SAF (Pc = 0.001) and a high VAT/SAT ratio (Pc = 0.002), whereas patients with the UCP3 -55 (rs1800849) TT presented high levels of VAF (Pc = 0.002). The results suggest the association of the UCP2 -866 (rs659366) polymorphism with risk of developing pCAD. Some polymorphisms were associated with abdominal fat levels and cardiovascular risk factors.

Type 2 Diabetes Mellitus is Associated with Carotid Artery Plaques in Patients with Premature Coronary Heart Disease.

BACKGROUND: In subjects without a history of coronary heart disease (CHD), type 2 diabetes mellitus (T2DM) is associated with carotid artery plaques (CAP), which is a better marker than high carotid intima-media thickness (hCIMT) for predicting first or recurrent cardiovascular events. OBJECTIVE: The objective of this study is to analyze the association of T2DM with CAP and hCIMT in premature CHD patients. METHODS: Premature CHD was considered before the age of 55 years in men and before 65 in women. T2DM was defined according to the American Diabetes Association criteria. CAP was defined as a focal structure encroaching the arterial lumen by at least 50% of the surrounding IMT value or with a thickness > 1.5 mm. RESULTS: Among 1196 patients (CHD duration 1.5 years [interquartile range: 0.4-5.6]), 37.2% had T2DM, and 97.8% were on antihypertensive, 94.4% on lipid-lowering, and 97.3% on anti-aggregate treatment. hCIMT prevalence was similar in patients with or without T2DM, whereas CAP prevalence was higher among T2DM patients (17.7% vs. 30.9%; p < 0.001). T2DM showed association with CAP, independently of CHD evolution and glycemic control (odds ratio: 1.57; 95% confidence interval: 1.09-2.26). CONCLUSIONS: T2DM has an independent association with CAP. Early detection of recurrent cardiovascular events, with CAP identification, could be useful to prevent complications in patients with CHD.

Interaction between FTO rs9939609 and the Native American-origin ABCA1 rs9282541 affects BMI in the admixed Mexican population.

BACKGROUND: The aim of this study was to explore whether interactions between FTO rs9939609 and ABCA1 rs9282541 affect BMI and waist circumference (WC), and could explain previously reported population differences in FTO-obesity and FTO-BMI associations in the Mexican and European populations. METHODS: A total of 3938 adults and 636 school-aged children from Central Mexico were genotyped for both polymorphisms. Subcutaneous and visceral adipose tissue biopsies from 22 class III obesity patients were analyzed for FTO and ABCA1 mRNA expression. Generalized linear models were used to test for associations and gene-gene interactions affecting BMI, WC and FTO expression. RESULTS: FTO and ABCA1 risk alleles were not individually associated with higher BMI or WC. However, in the absence of the ABCA1 risk allele, the FTO risk variant was significantly associated with higher BMI (P = 0.043) and marginally associated with higher WC (P = 0.067), as reported in Europeans. The gene-gene interaction affecting BMI and WC was statistically significant only in adults. FTO mRNA expression in subcutaneous abdominal adipose tissue according to ABCA1 genotype was consistent with these findings. CONCLUSIONS: This is the first report showing evidence of FTO and ABCA1 gene variant interactions affecting BMI, which may explain previously reported population differences. Further studies are needed to confirm this interaction.

IL-15 polymorphisms are associated with subclinical atherosclerosis and cardiovascular risk factors. The Genetics of Atherosclerosis Disease (GEA) Mexican Study.

Interleukin IL-15 (IL-15) has been implicated in the development of coronary artery disease (CAD). The aim of the present study was to evaluate the role of IL-15 gene polymorphisms as susceptibility markers for development of subclinical atherosclerosis (SA) and cardiovascular risk factors in Mexican population. Four IL-15 gene polymorphisms (rs4956403, rs3806798, rs1057972 and rs10833) were analyzed in a group of 397 individuals with SA and 1120 controls. Under different inheritance models adjusted by traditional risk factors, the rs10833T allele was associated with increased risk of developing SA [OR=1.42, Pcodom1=0.046; OR=1.48, Pdom=0.021; OR=1.43, Padd=0.014]. Under a dominant model, the rs1057972 polymorphism was associated with central obesity (P=0.045) and fatty liver (P=0.021), while the rs10833 polymorphism was associated with metabolic syndrome (P=0.007) in individuals with SA. The TAC haplotype was significantly associated with a decreased risk of SA. Individuals with rs10833CC genotype exhibited higher levels of IL-15 than individuals with CT+TT genotypes. The results suggest that IL-15 polymorphisms are involved in the risk of developing SA and are associated with metabolic syndrome, central obesity and fatty liver in our study population. The rs10833 polymorphism could be involved in regulating IL-15 production in SA.

Receptor-interacting protein 2 (RIP2) gene polymorphisms are associated with increased risk of subclinical atherosclerosis and clinical and metabolic parameters. The Genetics of Atherosclerotic Disease (GEA) Mexican study.

The receptor-interacting protein 2 (Rip2) is a serine/threonine kinase involved in multiple nuclear factor-κB (NFκB) activation pathways and is a key regulator of cellular lipid metabolism and cardiovascular disease. The aim of the present study was to evaluate the role of RIP2 gene polymorphisms as susceptibility markers for subclinical atherosclerosis (SA). Using an informatics analysis, four RIP2 gene polymorphisms with predicted functional effects (rs2293808, rs43133, rs431264, and rs16900627) were selected. The polymorphisms were genotyped in 405 individuals with SA (calcium score>0 assessed by computed tomography) and 1099 controls (calcium score=0). Clinical, anthropometric, tomographic and biochemical traits were measured. The association between the RIP2 polymorphisms and SA was evaluated using logistic regression analyses. Pair wise linkage disequilibrium (LD, D') estimations between polymorphisms and haplotype reconstruction were performed with Haploview version 4:1. Under different models adjusted by age, gender, body mass index, hypertension, diabetes mellitus, smoking habit, total cholesterol, HDL-cholesterol, LDL-cholesterol and triglyceride levels, rs43133 (OR=1.43, 95% CI: 1.05-1.94, P=0.022), and rs16900627 (OR=1.59, 95% CI: 1.00-2.54, Pdom=0.048 and OR=1.60, 95% CI: 1.05-2.54, Padd=0.028) were associated with increased risk of developing SA. Moreover, rs2293808, and rs431264 were associated with clinical or metabolic parameters in SA individuals and in healthy controls. The four polymorphisms were in high linkage disequilibrium and the GAAG haplotype was associated with increased risk of developing SA (OR=1.47, P=0.027). This study shows for the first time, that RIP2 polymorphisms are associated with increased risk of SA and with some clinical and metabolic parameters.

Interleukin 35 Polymorphisms Are Associated with Decreased Risk of Premature Coronary Artery Disease, Metabolic Parameters, and IL-35 Levels: The Genetics of Atherosclerotic Disease (GEA) Study.

Interleukin 35 (IL-35) is a heterodimeric cytokine involved in the development of atherosclerosis. The aim of the present study was to establish if the polymorphisms of IL-12A and EBI3 genes that encode the IL-35 subunits are associated with the development of premature coronary artery disease (CAD) in Mexican individuals. The IL-12A and EBI3 polymorphisms were determined in 1162 patients with premature CAD and 873 controls. Under different models, the EBI3 rs428253 (OR = 0.831, Padd = 0.036; OR = 0.614, Prec = 0.033; OR = 0.591, Pcod2 = 0.027) and IL-12A rs2243115 (OR = 0.674, Padd = 0.010; OR = 0.676, Pdom = 0.014; OR = 0.698, Phet = 0.027; OR = 0.694, Pcod1 = 0.024) polymorphisms were associated with decreased risk of developing premature CAD. Some polymorphisms were associated with clinical and metabolic parameters. Significant different levels of IL-35 were observed in EBI3 rs4740 and rs4905 genotypes only in the group of healthy controls. In summary, our study suggests that the EBI3 and IL-12A polymorphisms play an important role in decreasing the risk of developing premature CAD; it also demonstrates the relationship of the EBI3 rs4740 and rs4905 genotypes with IL-35 levels in healthy individuals.

Association of vitamin D deficiency with coronary artery disease in Mexican population: Genetics of atherosclerotic disease (GEA) study. / Deficiencia de vitamina D y su asociación con enfermedad arterial coronaria en población mexicana: estudio Genético de la Enfermedad Aterosclerosa.

Objective: To investigate the independent association between vitamin D deficiency (VDD) and coronary artery disease (CAD) in Mexican adult population. Method: Matched case-control study. Data cardiovascular on risk factors, medication use, physical activity, alcohol use, smoking and vitamin D consumption were obtained. Biochemical variables, anthropometric and blood pressure were measured. 25(OH)D was quantified by chemiluminescence. Results: We studied 250 patients with established CAD and 250 age-gender-body mass index (BMI) matched control subjects, with a mean age of 53 ± 6.1 years and BMI of 28 ± 3.5 kg/m2. Deficiency of 25(OH)D was significantly higher in the control group (21.2 vs. 16%). Multiple logistic regression analysis did not show association between VDD and CAD (OR: 1.37 [0.08-23.2]). Multiple linear regression analysis also showed that statin use (b = 2.2; p = 0.004) and no alcohol use (b = -1.8; p = 0.03) significantly increased 25(OH)D levels. Conclusions: No independent association between VDD and the presence of coronary artery disease was found in Mexican adult population. The results suggest that treatment with statins and absence of alcohol consumption, might be the explanation for the higher concentrations of 25(OH)D observed in patients with CAD.

Serum magnesium is inversely associated with coronary artery calcification in the Genetics of Atherosclerotic Disease (GEA) study.

BACKGROUND: Serum magnesium is inversely associated to coronary artery calcification (CAC) in patients with chronic kidney disease. There is little information on this association in a general healthy population. OBJECTIVE: The aim of this study was to examine the cross-sectional association of serum magnesium levels with CAC. METHODS: We included 1276 Mexican-mestizo subjects (50 % women), aged 30-75 years, free of symptomatic cardiovascular disease. CAC was quantified by multidetector computed tomography using the method described by Agatston. Cross-sectional associations of serum magnesium with cardiometabolic factors and subclinical atherosclerosis defined as a CAC score > 0, were examined in logistic regression models adjusted for age, sex, education, smoking status, body mass index, systolic blood pressure, physical activity, elevated abdominal visceral tissue, fasting insulin and glucose, alcohol consumption, menopausal status (women only), low (LDL-C) and high density lipoprotein cholesterol (HDL-C), triglycerides, diuretic use, type 2 diabetes mellitus (DM2), and family history of DM2. RESULTS: After full adjustment, subjects in the highest quartile of serum magnesium had 48 % lower odds of hypertension (p = 0.028), 69 % lower odds of DM2 (p = 0.003), and 42 % lower odds of CAC score > 0 (p = 0.016) compared to those with the lowest serum magnesium. The analyses also showed that a 0.17 mg/dL (1SD) increment in serum magnesium was independently associated with 16 % lower CAC (OR 0.84, 95 % CI 0.724-0.986). CONCLUSIONS: In a sample of Mexican-mestizo subjects, low serum magnesium was independently associated to higher prevalence not only of hypertension and DM2, but also to coronary artery calcification, which is a marker of atherosclerosis and a predictor of cardiovascular morbidity and mortality.

Microalbuminuria and its Association with Subclinical Atherosclerosis in the Mexican Mestizo population: the GEA study.

BACKGROUND: Microalbuminuria is an early marker of atherosclerosis. Ethnic differences for both conditions have been reported. We studied microalbuminuria prevalence and its association with coronary artery calcification as an early atherosclerosis marker in a Mexican-Mestizo population free of diabetes and hypertension (healthy), as well as in hypertensive and diabetic subjects. METHODS: In 1,472 adults (53.3 ± 9.4 years old, 50.3% women), anthropometric measurements, fasting blood glucose, and lipid profile were determined. A spot urine sample was used to quantify the albumin-to-creatinine ratio and to define microalbuminuria (20-200 mg/g in men, and 30-300 mg/g in women). A coronary artery calcification score was obtained by electron-beam computed tomography and subclinical atherosclerosis was defined as a score > 0. RESULTS: Overall microalbuminuria prevalence was 9.3% (5.4% in healthy, 11.6% in obese, 12% in hypertensive, and 25% in diabetic subjects). Compared to "healthy" subjects without microalbuminuria, those with microalbuminuria had a ∼3-fold higher prevalence of coronary artery calcification > 0, while normal-high albumin-to-creatinine ratio (OR: 1.8; p < 0.05) and microalbuminuria (OR: 2.6; p < 0.001) was independently associated with coronary artery calcification > 0 only among diabetic subjects. CONCLUSIONS: Microalbuminuria and high-normal albumin-to-creatinine ratio were independently associated with subclinical atherosclerosis, suggesting that they may confer a higher risk of future cardiovascular events.

Role of adiponectin and free fatty acids on the association between abdominal visceral fat and insulin resistance.

BACKGROUND: Experimental studies have shown that high free fatty acid (FFA) and low adiponectin (ADIPO) levels are involved in the mechanisms by which adiposity promotes insulin resistance (IR). However, no previous clinical studies have simultaneously analysed the relative contribution of FFA and ADIPO levels on the relation of abdominal visceral fat (AVF) with insulin resistance. OBJECTIVE: To analyse the contribution of low ADIPO (adiponectin < =p25th: 8.67 µg/mL in women and 5.30 µg/mL in men), and high FFAs (FFAs > =p75th: 0.745 mEq/L in women and 0.60 mEq/L in men) to the association of high AVF (AVF > =p75th: 127 cm2 in women; 152.7 cm2 in men) with insulin resistance (HOMA-IR > =75th: 3.58 in women and 3.12 in men), in non-diabetic subjects. MATERIAL AND METHODS: A cross-sectional analysis was performed including 1217 control participants of the Genetics of Atherosclerotic Disease study (GEA). Clinical, tomographic and biochemical parameters were measured in all participants. Logistic regression models were used to assess the association of high AVF with IR stratifying according to gender, and to normal or low ADIPO and normal or high FFA serum levels. RESULTS: In comparison to referent group, in men low ADIPO unlike high FFA increased the risk of IR. Females with normal AVF and low ADIPO, or high AVF and normal ADIPO had aprox 3 folds risk of IR (OR [IC95%]: 3.7 [2.1-6.6], p < 0.001, and 3.4 [2.0-5.7], p < 0.001; respectively). The risk increased to 7.6 [4.2-13.8], p < 0.001 when high AVF and low ADIPO were present. Irrespective of AVF, the effect of low ADIPO on IR was higher than that seen for high FFA. Besides, our results suggest an additive effect of high AVF, high FFA and low ADIPO on the IR prevalence. CONCLUSIONS: The present study provides novel and important information about the combined effect of high AVF and low ADIPO on the risk of IR. Furthermore, our data suggest that the effect of low adiponectin levels on the high AVF-IR association is stronger than that observed for high FFA, suggesting that adiponectin could be used as biomarker to identify subjects at high risk for T2DM and CAD.

The variant rs8048002 T>C in intron 3 of the MHC2TA gene is associated with risk of developing acute coronary syndrome.

Recently, an intronic single nucleotide polymorphism (rs8048002) in the MHC class II transactivator gene (MHC2TA) was shown to be associated with increased susceptibility to several inflammatory diseases. The aim of the present study was to test for an association between this MHC2TA gene polymorphism and susceptibility to the risk of developing acute coronary syndromes (ACS) in a group of Mexicans patients. The single nucleotide polymorphism (rs8048002) of the MHC2TA gene was analyzed by 5' exonuclease TaqMan genotyping assays in a group of 452 patients with ACS and 456 healthy controls. The C allele and TC genotype were associated with risk of developing ACS (OR=4.55, pC=6×10(-4) and OR=4.41, pC=1.5×10(-3), respectively). Multiple logistic analysis was used for estimate risk between ACS patients and controls adjusted by cardiovascular risk factors (gender, age, hypertension, dyslipidemia, smoking, diabetes, body mass index and alcohol consumption). In this analysis, the TC+CC genotypes were significantly associated with increased risk of ACS as compared to TT genotype (OR=4.56, pC=0.004). In summary, our data suggest that the MHC2TA rs8048002 C>T gene polymorphism plays an important role in the risk of developing ACS.