Toxic Metals and Subclinical Atherosclerosis in Carotid, Femoral, and Coronary Vascular Territories: The Aragon Workers Health Study

OBJECTIVE

Studies evaluating the association of metals with subclinical atherosclerosis are mostly limited to carotid arteries. We assessed individual and joint associations of nonessential metals exposure with subclinical atherosclerosis in 3 vascular territories. Approach and Results: One thousand eight hundred seventy-three Aragon Workers Health Study participants had urinary determinations of inorganic arsenic species, barium, cadmium, chromium, antimony, titanium, uranium, vanadium, and tungsten. Plaque presence in carotid and femoral arteries was determined by ultrasound. Coronary Agatston calcium score ≥1 was determined by computed tomography scan. Median arsenic, barium, cadmium, chromium, antimony, titanium, uranium, vanadium, and tungsten levels were 1.83, 1.98, 0.27, 1.18, 0.05, 9.8, 0.03, 0.66, and 0.23 μg/g creatinine, respectively. The adjusted odds ratio (95% CI) for subclinical atherosclerosis presence in at least one territory was 1.25 (1.03-1.51) for arsenic, 1.67 (1.22-2.29) for cadmium, and 1.26 (1.04-1.52) for titanium. These associations were driven by arsenic and cadmium in carotid, cadmium and titanium in femoral, and titanium in coronary territories and mostly remained after additional adjustment for the other relevant metals. Titanium, cadmium, and antimony also showed positive associations with alternative definitions of increased coronary calcium. Bayesian Kernel Machine Regression analysis simultaneously evaluating metal associations suggested an interaction between arsenic and the joint cadmium-titanium exposure.

CONCLUSIONS

Our results support arsenic and cadmium and identify titanium and potentially antimony as atherosclerosis risk factors. Exposure reduction and mitigation interventions of these metals may decrease cardiovascular risk in individuals without clinical disease.

High-quality intake of carbohydrates is associated with lower prevalence of subclinical atherosclerosis in femoral arteries: The AWHS study

BACKGROUND AND AIMS

High-quality of the carbohydrates consumed, apart from their total amount, appear to protect from cardiovascular disease (CVD). However, the relationship between the quality of carbohydrates and the early appearance of atherosclerosis has not yet been described. Our objective was to estimate the association between the quality of dietary carbohydrates and subclinical atherosclerosis in femoral and carotid arteries.

METHODS

Cross-sectional study of femoral and carotid atherosclerosis assessed using ultrasounds of 2074 middle-aged males, 50.9 (SD 3.9) years old, with no previous CVD, and pertaining to the Aragon Workers' Health Study (AWHS) cohort. Food frequency questionnaires were used to calculate a carbohydrate quality index (CQI) defined as: consumption of dietary fiber, a lower glycemic index, the ratio of whole grains/total grains, and the ratio of solid carbohydrates/total carbohydrates. The presence of plaques across four CQI intervals was studied using adjusted logistic regression models.

RESULTS

The CQI showed a direct inverse association with subclinical atherosclerosis in femoral territories. Participants with a higher consumption of high-quality carbohydrates (13-15 points) were less likely to have femoral plaques when compared with participants in the lowest index interval (4-6 points) (OR = 0.59; 95% CI = 0.39, 0.89; p = 0.005). No association was found between the CQI and the presence of subclinical atherosclerosis in carotid territories. A lower consumption of high-quality carbohydrates tended to be associated with a greater atherosclerosis extension, considered as the odds for having more affected territories (p = 0.011).

CONCLUSIONS

Among middle-aged males, a high-quality intake of carbohydrates is associated with a lower prevalence of femoral artery subclinical atherosclerosis when compared with a lower consumption. Thus, indicating an early relationship between the quality of carbohydrates and the development of CVD.

Three Dimensional Carotid and Femoral Ultrasound is not Superior to Two Dimensional Ultrasound as a Predictor of Coronary Atherosclerosis Among Men With Intermediate Cardiovascular Risk

BACKGROUND

Current cardiovascular disease (CVD) risk stratification scales, drawn up from traditional risk factors, have important limitations. The detection of subclinical atherosclerosis, by a non-invasive technique such as peripheral arteries ultrasound (US) may improve cardiovascular risk (CVR) stratification, especially in intermediate risk population. Our aim was to compare the predictive power of atherosclerotic plaques detected in carotid and femoral arteries by 2-dimensional (2D) vs. 3-dimensional (3D) US for positive coronary artery calcium score (CACS), used as a proxy for CVD, in a middle-aged sample with intermediate 10-year CVR (7.5-20%).

METHODS

To detect atherosclerotic plaques by 2D vs. 3D US scan of carotid and femoral arteries and comparison of their association with CACS obtained by computed tomography (CT) of subjects with intermediate CVR belonging to the Aragon Workers' Health Study.

RESULTS

120 men were included, with a 10.4% average 10 years CVR. Forty-one (34.2%) participants had CACS ≥ 1. 90 participants (75%) had at least one plaque detected by 2D scan while 85 participants (70.8%) had at least a plaque detected by 3D US. Conventional CVR estimates c-statistic for CACS was .590. Although the variables most predicted of CACS ≥ 1 were those measured by 3D US (total plaque volume and mean of plaque density, c-statistics: .743 and .750 respectively), their predictive capacity was not statistically significantly different from the number of territories with plaque, measured either by 2D and 3D US (c-statistics .728 to .740 respectively).

CONCLUSION

Subclinical atherosclerosis measured by 2D and 3D US were better predictors of CACS ≥ 1 than CVR estimated by conventional guidelines. In our sample, 3D US did not show any significant advantages with respect to 2D US for the prediction of coronary atherosclerosis.

In silico epigenetics of metal exposure and subclinical atherosclerosis in middle aged men: pilot results from the Aragon Workers Health Study

We explored the association of metal levels with subclinical atherosclerosis and epigenetic changes in relevant biological pathways. Whole blood DNA Infinium Methylation 450 K data were obtained from 23 of 73 middle age men without clinically evident cardiovascular disease (CVD) who participated in the Aragon Workers Health Study in 2009 (baseline visit) and had available baseline urinary metals and subclinical atherosclerosis measures obtained in 2010-2013 (follow-up visit). The median metal levels were 7.36 µg g^-1, 0.33 µg g^-1, 0.11 µg g^-1 and 0.07 µg g^-1, for arsenic (sum of inorganic and methylated species), cadmium, antimony and tungsten, respectively. Urine cadmium and tungsten were associated with femoral and carotid intima-media thickness, respectively (Pearson's r = 0.27; p = 0.03 in both cases). Among nearest genes to identified differentially methylated regions (DMRs), 46% of metal-DMR genes overlapped with atherosclerosis-DMR genes (p < 0.001). Pathway enrichment analysis of atherosclerosis-DMR genes showed a role in inflammatory, metabolic and transport pathways. In in silico protein-to-protein interaction networks among proteins encoded by 162 and 108 genes attributed to atherosclerosis- and metal-DMRs, respectively, with proteins known to have a role in atherosclerosis pathways, we observed hub proteins in the network associated with both atherosclerosis and metal-DMRs (e.g. SMAD3 and NOP56), and also hub proteins associated with metal-DMRs only but with relevant connections with atherosclerosis effectors (e.g. SSTR5, HDAC4, AP2A2, CXCL12 and SSTR4). Our integrative in silico analysis demonstrates the feasibility of identifying epigenomic regions linked to environmental exposures and potentially involved in relevant pathways for human diseases. While our results support the hypothesis that metal exposures can influence health due to epigenetic changes, larger studies are needed to confirm our pilot results.This article is part of a discussion meeting issue 'Frontiers in epigenetic chemical biology'.

Arsenic exposure, diabetes-related genes and diabetes prevalence in a general population from Spain

Inorganic arsenic exposure may be associated with diabetes, but the evidence at low-moderate levels is not sufficient. Polymorphisms in diabetes-related genes have been involved in diabetes risk. We evaluated the association of inorganic arsenic exposure on diabetes in the Hortega Study, a representative sample of a general population from Valladolid, Spain. Total urine arsenic was measured in 1451 adults. Urine arsenic speciation was available in 295 randomly selected participants. To account for the confounding introduced by non-toxic seafood arsenicals, we designed a multiple imputation model to predict the missing arsenobetaine levels. The prevalence of diabetes was 8.3%. The geometric mean of total arsenic was 66.0 μg/g. The adjusted odds ratios (95% confidence interval) for diabetes comparing the highest with the lowest tertile of total arsenic were 1.76 (1.01, 3.09) and 2.14 (1.47, 3.11) before and after arsenobetaine adjustment, respectively. Polymorphisms in several genes including IL8RA, TXN, NR3C2, COX5A and GCLC showed suggestive differential associations of urine total arsenic with diabetes. The findings support the role of arsenic on diabetes and the importance of controlling for seafood arsenicals in populations with high seafood intake. Suggestive arsenic-gene interactions require confirmation in larger studies.

Influence of cardiovascular condition on retinal and retinal nerve fiber layer measurements

OBJECTIVE

To assess changes in the retinal nerve fiber layer (RNFL) and macula in subjects with cardiovascular risk factors or subclinical ischemia.

DESIGN

Prospective and observational study.

METHODS

A total of 152 healthy men underwent cardiovascular examination, including quantification of subclinical atheroma plaques by artery ultrasound scans, blood analysis, and a complete ophthalmic evaluation, including spectral-domain optical coherence tomography. The variables registered in cardiovascular examination were quantification of classic major risk factors, subclinical atheroma plaques by artery ultrasound scans, and analytical records. The ophthalmic evaluation registered RNFL and macular thickness.

RESULTS

Mean subject age was 51.27±3.71 years. The 40 subjects without classic cardiovascular risk factors did not show differences in RNFL and macular thicknesses compared with the 112 subjects with at least one risk factor (except in sector 9 that showed higher thicknesses in subjects with ≥1 risk factor). Comparison between the group of subjects with and without atheroma plaques revealed no differences in RNFL and macular thicknesses. The sub-analysis of subjects with subclinical atheroma plaques in the common carotid artery revealed a significant reduction in central macular thickness in the left eye compared with the right eye (p = 0.016), RNFL in the superior quadrant (p = 0.007), and the 11 o'clock sector (p = 0.020). Comparison between smokers and nonsmokers revealed that smokers had significant thinning of the central macular thickness (p = 0.034), the nasal RNFL quadrant (p = 0.006), and the 3 and 5 o'clock sectors (p = 0.016 and 0.009).

CONCLUSIONS

Classic cardiovascular risk factors do not cause RNFL or macular thickness reduction, but tobacco smoking habit reduces nasal RNFL thickness. Subclinical atherosclerosis in the common carotid artery associates a reduction in central macular and nasal RNFL quadrant thicknesses in the left eye compared with the right eye.

Identification of differentially methylated BRCA1 and CRISP2 DNA regions as blood surrogate markers for cardiovascular disease

Genome-wide Illumina InfiniumMethylation 450 K DNA methylation analysis was performed on blood samples from clinical atherosclerosis patients (n = 8) and healthy donors (n = 8) in the LVAD study (NCT02174133, NCT01799005). Multiple differentially methylated regions (DMR) could be identified in atherosclerosis patients, related to epigenetic control of cell adhesion, chemotaxis, cytoskeletal reorganisations, cell proliferation, cell death, estrogen receptor pathways and phagocytic immune responses. Furthermore, a subset of 34 DMRs related to impaired oxidative stress, DNA repair, and inflammatory pathways could be replicated in an independent cohort study of donor-matched healthy and atherosclerotic human aorta tissue (n = 15) and human carotid plaque samples (n = 19). Upon integrated network analysis, BRCA1 and CRISP2 DMRs were identified as most central disease-associated DNA methylation biomarkers. Differentially methylated BRCA1 and CRISP2 regions were verified by MassARRAY Epityper and pyrosequencing assays and could be further replicated in blood, aorta tissue and carotid plaque material of atherosclerosis patients. Moreover, methylation changes at BRCA1 and CRISP2 specific CpG sites were consistently associated with subclinical atherosclerosis measures (coronary calcium score and carotid intima media thickness) in an independent sample cohort of middle-aged men with subclinical cardiovascular disease in the Aragon Workers’ Health Study (n = 24). Altogether, BRCA1 and CRISP2 DMRs hold promise as novel blood surrogate markers for early risk stratification and CVD prevention.

Lower-normal TSH is associated with better metabolic risk factors: A cross-sectional study on Spanish men

BACKGROUND AND AIMS

Subclinical thyroid conditions, defined by normal thyroxin (T4) but abnormal thyroid-stimulating hormone (TSH) levels, may be associated with cardiovascular and metabolic risk. More recently, TSH levels within the normal range have been suggested to be associated with metabolic syndrome and cardiovascular risk. This work studies the linearity of the relationship between metabolic syndrome and TSH across the euthyroid range.

METHODS AND RESULTS

We studied 3533 male participants of the Aragon Workers' Health Study (AWHS) with normal TSH and free T4 levels, across quintiles of these variables, after adjusting for age, alcohol intake, and smoking. Compared with the lowest TSH quintile, the odds ratios for metabolic syndrome at the higher quintiles, which indicate lower thyroid function, were 1.34 (1.04, 1.73), 1.56 (1.21, 2.01), 1.57 (1.22, 2.03), and 1.71 (1.32, 2.21). The lowest free T4 quintile also showed an odds ratio of 1.49 (1.16, 1.90) with respect to the highest quintile. In addition, spline models showed departures from linearity: the risk of metabolic syndrome mostly increases at TSH values below the median (sample half-closest to subclinical hyperthyroidism). Interestingly, glucose also increases with TSH primarily below the median TSH, diastolic blood pressure shows similar changes across the entire TSH range, whereas body mass index, triglycerides, and high-density lipoprotein (HDL)-cholesterol change only at the highest normal TSH values, which are associated with lower free T4 concentration.

CONCLUSIONS

TSH and free T4 within the normal range are associated with the metabolic syndrome. The sample half-below the TSH median (with probably higher functional thyroid status) exhibited better metabolic and cardiovascular profiles.

A genetic variant in the LDLR promoter is responsible for part of the LDL-cholesterol variability in primary hypercholesterolemia

BACKGROUND

GWAS have consistently revealed that LDLR locus variability influences LDL-cholesterol in general population. Severe LDLR mutations are responsible for familial hypercholesterolemia (FH). However, most primary hypercholesterolemias are polygenic diseases. Although Cis-regulatory regions might be the cause of LDL-cholesterol variability; an extensive analysis of the LDLR distal promoter has not yet been performed. We hypothesized that genetic variants in this region are responsible for the LDLR association with LDL-cholesterol found in GWAS.

METHODS

Four-hundred seventy-seven unrelated subjects with polygenic hypercholesterolemia (PH) and without causative FH-mutations and 525 normolipemic subjects were selected. A 3103 pb from LDLR (-625 to +2468) was sequenced in 125 subjects with PH. All subjects were genotyped for 4 SNPs (rs17242346, rs17242739, rs17248720 and rs17249120) predicted to be potentially involved in transcription regulation by in silico analysis. EMSA and luciferase assays were carried out for the rs17248720 variant. Multivariable linear regression analysis using LDL-cholesterol levels as the dependent variable were done in order to find out the variables that were independently associated with LDL-cholesterol.

RESULTS

The sequencing of the 125 PH subjects did not show variants with minor allele frequency ≥ 10%. The T-allele from g.3131C > T (rs17248720) had frequencies of 9% (PH) and 16.4% (normolipemic), p < 0.00001. Studies of this variant with EMSA and luciferase assays showed a higher affinity for transcription factors and an increase of 2.5 times in LDLR transcriptional activity (T-allele vs C-allele). At multivariate analysis, this polymorphism with the lipoprotein(a) and age explained ≈ 10% of LDL-cholesterol variability.

CONCLUSION

Our results suggest that the T-allele at the g.3131 T > C SNP is associated with LDL-cholesterol levels, and explains part of the LDL-cholesterol variability. As a plausible cause, the T-allele produces an increase in LDLR transcriptional activity and lower LDL-cholesterol levels.

Association of endothelial function and vascular data with LDL-c and HDL-c in a homogeneous population of middle-aged, healthy military men: Evidence for a critical role of optimal lipid levels

BACKGROUND

Modifying lipids levels underpins atherosclerosis prevention. Flow-mediated dilation (FMD) could advise which patients to treat and to what extent. Little is known about the influence of near-normal lipid levels on the endothelium and the mechanisms related to different lipid fractions. We studied associations between FMD and lipids, focusing on normal lipid levels.

METHODS

An age-homogeneous sample of 171 healthy, untreated military men (mean age 35.5+/-1.1 years) was studied: serum lipid determination and brachial artery ultrasound with a forearm ischemia cuff and automated measurement were performed. NCEP-ATP III groups were used.

RESULTS

Significantly smaller vessel diameters were found among individuals with high HDL-c (4.10 mm vs. 4.24 mm), optimal LDL-c (4.00 mm vs. 4.22 mm), and normal triglycerides (<150 mg/dl) (4.15 mm vs. 4.31 mm). Basal diameter correlated significantly with HDL-c and triglycerides. There were significant differences in FMD between low HDL-c compared to the rest (4.13% vs. 5.07%) and between optimal and near-optimal LDL-c compared to the rest (5.28% vs. 4.56%). HDL-c and LDL-c correlated with FMD. The inverse relation of high LDL-c and FMD is partially due to a decreased stimulus. Besides, stimulus heterogeneity may mask HDL-c link with FMD.

CONCLUSION

Those subjects naturally (not pharmacologically) in the healthy tail-end of the lipid distributions have the best endothelial function and smaller vessels. Functional vascular remodeling might precede anatomical remodeling and, in early stages, vessel size should be considered a risk indicator rather than an atherosclerotic sign. Furthermore, controlling the stimulus seems necessary for detecting the relationship between HDL-c and FMD, and should be performed regularly.

Prehypertension is associated with insulin resistance state and not with an initial renal function impairment. A Metabolic Syndrome in Active Subjects in Spain (MESYAS) Registry substudy

BACKGROUND

The aim of this study was to assess the prevalence of metabolic syndrome (MS) and other surrogate markers of insulin resistance, and whether these markers are better for defining the prehypertensive state than is renal dysfunction.

METHODS

Data from 19,041 healthy active workers, mean age 42.2 (10.7) years, from three health insurance companies, were prospectively collected. Presence of MS, assessed according to the modified criteria of the National Cholesterol Education Program Third Adult Treatment Panel, and the ratio of triglycerides to high-density lipoprotein were considered as surrogate markers of insulin resistance. Renal function was assessed by the Modification of Diet in Renal Disease Study equation. Blood pressure was classified as normotension (NT), prehypertension (PHT), or hypertension (HT) according to the guidelines of the seventh report of the Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure.

RESULTS

The global presence of MS was 11.8% The higher prevalence was found in subjects with hypertension (30%), followed by those with PHT (9.6%). The prevalence in normotensive subjects was very low (0.9%). The presence of MS and hypertension increased in parallel with age. Metabolic syndrome (odds ratio [OR] 4.3), obesity (OR 2.2), overweight (OR 1.7), impaired fasting glucose (OR 1.3), and elevated triglycerides to HDL ratio (OR 1.2), but no degree of renal dysfunction, were independent risk factors for the progression from NT to PHT.

CONCLUSIONS

Prehypertension is associated with markers of insulin resistance, assessed by the presence of MS and other surrogate markers, and not with an initial renal dysfunction. In this study, MS was found to be present in almost one third of hypertensive but asymptomatic and otherwise healthy workers.

[Guidelines of the Spanish Society of Cardiology for cardiovascular disease prevention and cardiac rehabilitation]

The priorities for the prevention of cardiovascular diseases should be focused on patients with established disease and high risk subjects, with individual global risk always being taken into account. The current evidence on the influence of the main risk factors are unanimous (dyslipemia, tobacco, hypertension and diabetes mellitus), being somewhat less so in cases of sedentarism, obesity and the metabolic syndrome. The evidence concerning other risk factors still remains controversial. Guidelines for the control of the different risk factors should be based on the evidence derived from both epidemiological or clinical trials. The recommendations published by several scientific societies should also be followed. There are, at present, important evidence on the efficacy of smoking cessation, the treatment of arterial hypertension and particularly on the successful control of lipid levels with lipid-lowering drugs, especially with statins. There is also evidence on the need for rigorous control of diabetic patients not only in relation to the glucose levels but also to dyslipemia. The most efficient measures for a reduction in morbidity and mortality are cessation of smoking, appropriate hypertensive therapy, a comprehensive program of cardiac rehabilitation and overall the successful control of lipid levels with statins.

[Primary angiosarcoma of the heart. A report of a new case and a review of the literature]

The case is presented of a primitive heart angiosarcoma (PHA) in a 53-year-old woman who developed repeated episodes of hemopericardium with cardiac tamponade. A literature review is performed. PHA is the most frequent primitive cardiac tumor. It is usually localized in the right striatum and is accompanied by effusion of pericardium and right heart failure. The diagnosis is usually made late and bidimensional echography is of great value. Treatment is surgical, if possible. Chemotherapy protocols are being used but with obscure prognosis.

Tobacco, physical exercise and lipid profile

A group of 572 young cadets from the General Military Academy in Zaragoza (AGEMZA) with a mean age of 19.9 years was studied in two different situations: on admission to the AGEMZA, when physical activity was very intensive (A) and after 8 months, by which time they had all received identical diets and physical activity was considerably reduced (B). On both occasions they were asked about their smoking habits and their personal and family histories. Their height and weight were recorded and a sample of venous blood was taken to determine the lipid, biochemical and haematological profiles. We found that more smokers had a family history of sudden death or acute myocardial infarction than the non-smokers. The smokers also showed a lower HDL cholesterol level (54.3 +/- 9.8 mg.dl-1 +/- SD) than the non-smokers (59.4 +/- 10.9) (P less than 0.0001) and a higher level of triglycerides (75.4 +/- 24.7 mg.dl-1) than the non-smokers (65.4 +/- 21.1 mg.dl-1). The smokers had a higher white cell count (8194 +/- 1981 vs 7332 +/- 1672 cells. 10mm-3) (P less than 0.001), a higher haemoglobin value (14.9 +/- 0.9 vs 14.6 +/- 0.9 g.dl-1) (P less than 0.004) and a higher haematocrit value (44.2 +/- 2.3 vs 43.6 +/- 2.7%) (P less than 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)

[Multicenter study of atenolol, combined with hydralazine and bendroflumethiazide in the treatment of essential, mild, and severe, arterial hypertension]

The aim of the present study was to determine both the effectiveness and tolerance of a preparation constituted by the combination at fixed doses of a betablocker (atenolol, 100 mg), a diuretic (bendroflumethiazide, 5 mg) and a vasodilator (hydralazine, 50 mg). The study was carried out on a sample formed by 46 patients with moderate or severe essential hypertension who received this preparation as a single antihypertensive therapy during 2 months. As for the hypotensive effectiveness of the product, obtained results demonstrate that arterial blood pressure (BP) levels were normalized in 89% of the patients with moderate essential hypertension and in 9/10 patients with severe hypertension. Tolerance was excellent in most of the cases. Although new studies should be performed in order to enlarge the number of available case-studies, the above presented data allow us to conclude with a positive opinion about the studied combination.