Trans fat involvement in cardiovascular disease

Coronary heart disease is becoming a worldwide epidemic and diet and lifestyle are well known contributing factors. Identifying the kinds of foods that may have a cardioprotective or cardiotoxic effect and understanding their molecular mechanisms of action has become of increasing importance. Through largely epidemiological evidence, trans fatty acid (TFA) intake has been associated with a variety of cardiovascular complications including atherosclerosis. Traditionally, industrial TFAs (iTFAs) have been associated with these deleterious cardiovascular effects. However, there is a current body of research that suggests that ruminant trans fats (rTFAs) may have a cardioprotective role within the heart. The molecular mechanisms whereby TFAs are delivering their effects are largely unknown. In the following review, we discuss recent in vitro, animal and epidemiological research to better understand the effect of TFAs in the diet on cardiovascular disease, particularly atherosclerosis.     

Adaptations in beta-adrenergic cardiovascular responses to training in older women.

To determine whether endurance exercise training can alter the beta-adrenergic-stimulated inotropic response in older women, we studied 10 postmenopausal healthy women (65.4 +/- 0.9 yr old) who exercised for 11 mo. Left ventricular (LV) function was evaluated with two-dimensional echocardiography during infusion of isoproterenol after atropine. Maximal O(2) consumption increased 23% in response to training (from 1.35 +/- 0.06 to 1.66 +/- 0.07 l/min; P = 0.004). Training had no effect on baseline LV function, end-diastolic diameter, LV wall thickness, or LV mass. The increase in LV systolic function in response to isoproterenol was unaffected by training. Furthermore, neither the systolic shortening-to-end-systolic wall stress relationship nor the end-systolic wall stress-to-end-systolic diameter relationship during isoproterenol infusion changed with training. We conclude that older postmenopausal women can increase their maximal O(2) consumption with exercise training without eccentric LV hypertrophy or enhancement of beta-adrenergic-mediated LV contractile function. These observations provide an explanation for the finding that maximal cardiac output and stroke volume are not increased in older women in response to training.     

Effect of sarcopenia on cardiovascular disease risk factors in obese postmenopausal women

Objective: To compare sarcopenic‐obese and obese postmenopausal women for risk factors predisposing to cardiovascular disease (CVD) and determine whether there may be a relationship between muscle mass and metabolic risk in obese postmenopausal women. Research Methods and Procedures: In this cross‐sectional study, 22 healthy obese postmenopausal women (mean age, 66 ± 5 years; mean BMI, 27 ± 3 kg/m²) were divided into two groups matched for age (±2 years) and fat mass (FM) (±2%). Sarcopenia was defined as a muscle mass index of <14.30 kg fat‐free mass (FFM)/m² (which corresponds to 1 standard deviation below the values of a young reference population), and obesity was defined as an FM of >35% (which corresponds to the World Health Organization guidelines). FM, FFM (measured by DXA), daily energy expenditure (accelerometry), dietary intake (3‐day dietary record), and blood biochemical analyses (lipid profile, insulin, glucose, and C‐reactive protein) were obtained. Visceral fat mass (VFM) was calculated by the equation of Bertin, which estimates VFM from DXA measurements. Results: Obese women had more FFM (p = 0.006), abdominal FM (p = 0.047), and VFM (p = 0.041) and a worse lipid profile [p = 0.040 for triglycerides; p = 0.004 for high‐density lipoprotein (HDL); p = 0.026 for total cholesterol/HDL] than sarcopenic‐obese postmenopausal women. Obese women also ingested significantly more animal (p = 0.001) and less vegetal proteins (p = 0.013), although both groups had a similar total protein intake (p = 0.967). Discussion: Sarcopenia seems to be associated with lower risk factors predisposing to CVD in obese postmenopausal women. With the increase in the number of aging people, the health implications of being sarcopenic‐obese merit more attention.     

Genes, fat intake, and cardiovascular disease risk factors in the Quebec Family Study

Objective: The aim of this study was to assess gene‐diet interaction effects on cardiovascular disease (CVD) risk factors (waist circumference, plasma triacylglycerol, high‐density lipoprotein‐cholesterol and fasting glucose concentrations, and diastolic and systolic blood pressure) in the Quebec Family Study cohort. Design: Sixty‐four polymorphisms from 45 candidate genes were studied in 645 subjects. Dietary fat intake was obtained from a 3‐day weighted food record. Results: We observed 18 significant interactions at a p value ≤ 0.01. Among them, the Pro12Ala polymorphism in peroxisome proliferator‐activated receptor γ, alone or in interaction with fat intake, significantly modulated waist circumference (p = 0.0005 for both effects). Additionally, the apolipoprotein E genotype in interaction with fat intake was significantly associated with diastolic and systolic blood pressure (p = 0.01 and p = 0.001, respectively). The ghrelin Leu72Met polymorphism also interacted with dietary fat in its relation to waist circumference and triacylglycerol concentrations (p = 0.0004 and p = 0.005). Discussion: These results suggest that several alleles at candidate genes interact with dietary fat intake to modulate well‐known CVD risk factors. The identification of gene‐diet interaction effects is likely to provide useful information concerning the etiology of CVD.     

Review of cardiovascular risk factors in women

Background: Although cardiovascular disease (CVD) is the leading cause of death in women in the United States, a knowledge gap persists regarding the mechanisms and management of CVD in women. Before treatment can be optimized, the role of cardiovascular risk factors must be elucidated.Objective: This review provides an updated assessment of cardiovascular risk factors in women, with a focus on cardiometabolic risk.Methods: MEDLINE and Cochrane Library databases, and statistics from the National Health and Nutrition Examination Survey and the American Heart Association, were searched from 1990 to September 2008 using the following terms: cardiovascular risk factors, women, gender, cardiometabolic risk, abdominal obesity, and metabolic syndrome. Publications were classified as English-only original data, reviews, and clinical guidelines. Nonpublished data were excluded. Data were extracted by 2 reviewers independently.Results: Investigators performing multivariable predictive models have estimated that traditional risk factors account for ~70% of the variance in estimating cardiovascular events. However, substantial sex differences exist in the prevalence of traditional risk factors as well as in cardiovascular outcomes. Hypertension is more prevalent in men until the age of 59 years, but then contributes to greater morbidity in older women. Low levels of high-density lipoprotein and elevated triglyceride levels pose more of a threat to women, yet high levels of low-density lipoprotein pose equal risk for women and men. The CVD mortality rate is -3 times greater in people with diabetes than in those without diabetes. Among diabetic individuals, CVD mortality is slightly higher in women compared with men.Conclusions: Increased knowledge of gender-specific risks for CVD has led to national campaigns to educate women. In addition to traditional risk factors, cardiometabolic risk is an important consideration in women. Controversy exists regarding the exact definitions and usefulness of the term metabolic syndrome, but it is clear that the presence of certain factors contributes to increased morbidity and mortality in affected individuals. Abdominal obesity links insulin resistance, dyslipidemia, and hypertension through complex endocrine pathways. Current research is identifying gene × gender interactions, and continued research is necessary to explore the relationship of sex steroids and cardiovascular risk in both men and women.     

Oxidative risk for atherothrombotic cardiovascular disease

In the vasculature, reactive oxidant species, including reactive oxygen, nitrogen, or halogenating species, and thiyl, tyrosyl, or protein radicals may oxidatively modify lipids and proteins with deleterious consequences for vascular function. These biologically active free radical and nonradical species may be produced by increased activation of oxidant-generating sources and/or decreased cellular antioxidant capacity. Once formed, these species may engage in reactions to yield more potent oxidants that promote transition of the homeostatic vascular phenotype to a pathobiological state that is permissive for atherothrombogenesis. This dysfunctional vasculature is characterized by lipid peroxidation and aberrant lipid deposition, inflammation, immune cell activation, platelet activation, thrombus formation, and disturbed hemodynamic flow. Each of these pathobiological states is associated with an increase in the vascular burden of free radical species-derived oxidation products and, thereby, implicates increased oxidant stress in the pathogenesis of atherothrombotic vascular disease.     

Dyslipidaemia and inflammatory markers as the risk predictors for cardiovascular disease in newly diagnosed premenopausal hypothyroid women

BackgroundHypothyroidism can predispose systolic and diastolic cardiac dysfunction, increased peripheral vascular resistance, endothelial dysfunction, altered coagulopathy, and dyslipidemia resulting in atherosclerosis. Thyroid hormones can influence homocysteine metabolism by regulating the methylenetetrahydrofolate reductase (M THR). So, this study aimed to compare the markers homocysteine, high sensitive C-reactive protein (hs-CRP), and Atherogenic Indices (AI) between newly diagnosed hypothyroid and euthyroid premenopausal women.Methods80 Female patients between 20 and 45 years were enrolled in this study and were equally divided into cases and controls group. Laboratory tests included: i) Serum T3, T4, TSH was measured using electrochemiluminescence, ii) lipid profile, homocysteine, and hs-CRP were measured for all the participants. Atherogenic indices: Castelli risk indices I&II, Atherogenic coefficient (AEC), and Atherogenic Index of Plasma (AIP) were calculated using formulas. A comparison between the study groups was made by using the Independent t-test and Mann-Whitney U test. p-value < 0.05 was considered significant.ResultsThe hypothyroid group had significantly higher levels of homocysteine (p= 0.014), and hs-CRP (hs-CRP> 3.0 mg/L, 70% of participants have intermediate to high risk for a cardiovascular event) and elevated BMI compared to participants in the euthyroid group. Atherogenic indices (p< 0.001) was significantly increased in the hypothyroid participants'' group. TC, TG , and LDL were significantly elevated in the hypothyroid group but did not show any association with systolic and diastolic blood pressure.ConclusionsPremenopausal women with hypothyroidism have a greater predisposition for cardiovascular disease compared to euthyroid     

Changes in ponderal index and body mass index across childhood and their associations with fat mass and cardiovascular risk factors at age 15

Background

Little is known about whether associations between childhood adiposity and later adverse cardiovascular health outcomes are driven by tracking of overweight from childhood to adulthood and/or by vascular and metabolic changes from childhood overweight that persist into adulthood. Our objective is to characterise associations between trajectories of adiposity across childhood and a wide range of cardiovascular risk factors measured in adolescence, and explore the extent to which these are mediated by fat mass at age 15.

Methods and Findings

Using data from the Avon Longitudinal Study of Parents and Children, we estimated individual trajectories of ponderal index (PI) from 0–2 years and BMI from 2–10 years using random-effects linear spline models (N = 4601). We explored associations between PI/BMI trajectories and DXA-determined total-body fat-mass and cardiovascular risk factors at 15 years (systolic and diastolic blood pressure, fasting LDL- and HDL-cholesterol, triglycerides, C-reactive protein, glucose, insulin) with and without adjustment for confounders. Changes in PI/BMI during all periods of infancy and childhood were associated with greater DXA-determined fat-mass at age 15. BMI changes in childhood, but not PI changes from 0–2 years, were associated with most cardiovascular risk factors in adolescence; associations tended to be strongest for BMI changes in later childhood (ages 8.5–10), and were largely mediated by fat mass at age 15.

Conclusion

Changes in PI/BMI from 0–10 years were associated with greater fat-mass at age 15. Greater increases in BMI from age 8.5–10 years are most strongly associated with cardiovascular risk factors at age 15, with much of these associations mediated by fat-mass at this age. We found little evidence supporting previous reports that rapid PI changes in infancy are associated with future cardiovascular risk. This study suggests that associations between early overweight and subsequent adverse cardiovascular health are largely due to overweight children tending to remain overweight.     

Adiponectin and visceral fat associate with cardiovascular risk factors

Objective: To examine the combined effect of CT‐measured visceral fat area (VFA) and adiponectin level against the clustering of metabolic risk factors. Design and Methods: The subjects were 6,996 Japanese. The subjects were divided according to the combinations of VFA and adiponectin level quartiles and the odds ratio for multiple risk factors of metabolic syndrome were calculated (adjusted for age and lifestyle factors using logistic regression analyses). Group with the lowest VFA and the highest adiponectin level was used as a reference. The correlation between adiponectin level and each metabolic risk factor was evaluated. Results: The strongest correlation was observed between adiponectin level and high‐density lipoprotein cholesterol levels (r = 0.369 and 0.439 for men and women). Both VFA and adiponectin level were independently associated with the clustering of metabolic risk factors (interaction P = 0.58 and 0.11 for men and women). The odds ratio for the clustering of metabolic risk factors in the group with the highest VFA and the lowest adiponectin level, compared with the group with the lowest VFA and the highest adiponectin level, was 12.7 (9.7‐16.6) for men and 13.5 (6.0‐30.2) for women. Conclusion: The ability to detect metabolic syndrome could be improved by examining adiponectin level in conjunction with VFA.     

Bivariate whole-genome linkage scan for bone geometry and total body fat mass

To quantify the genetic correlations between total body fat mass （TBFM） and femoral neck geometric parameters （FNGPs） and, if pos- sible, to detect the specific genomic regions shared by them, bivariate genetic analysis and bivariate whole-genome linkage scan were carried out in a large Caucasian population. All the phenotypes studied were significantly controlled by genetic factors （P 〈 0.001） with the heritabilities ranging from 0.45 to 0.68. Significantly genetic correlations were found between TBFM and CSA （cross-section area）, W （sub-periosteal diameter）, Z （section modulus） and CT （cortical thickness） except between TBFM and BR （buckling ratio）. The peak bivariate LOD scores were 3.23 （20q12）, 2.47 （20p11）, 3.19 （6q27）, 1.68 （20p12）, and 2.47 （7q11） for the five pairs of TBFM and BR, CSA, CT, W, and Z in the entire sample, respectively. Gender-specific bivariate linkage evidences were also found for the five pairs. 6p25 had complete pleiotropic effects on the variations of TBFM ＆ Z in the female sub-population, and 6q27 and 17q11 had coincident link- ages for TBFM ＆ CSA and TBFM ＆ Z in the entire population. We identified moderate genetic correlations and several shared genomic regions between TBFM and FNGPs in a large Caucasian population.     

Obesity and cardiovascular risk factors among men and women aged 40 years and older in a rural area of Japan

Obesity is one of the most common health problems, and is recognized worldwide as an "escalating epidemic." For the establishment of an obesity-prevention strategy in Japan, it is important to assess the association between obesity and cardiovascular risk factors. Therefore, we conducted anthropometric measures of obesity and investigated the association of obesity with cardiovascular risk factors such as hypertension, diabetes, and dyslipidemia among community-dwelling men (N=85) and women (N=173) aged 40 years and older. Height, weight, and waist circumference (WC) were measured, and body mass index (BMI) was calculated. Subjects with a BMI> or =25 kg/m(2) were considered obese (BMI obesity), while men with a WC> or =85 cm and women with a WC> or =90 cm were classified as obese (WC obesity). In the present study, we defined 'obesity' as a BMI> or =25 kg/m(2) or a WC> or =85 cm for men, and a BMI> or =25 kg/m(2) or a WC> or =90 cm for women. The results of an age- and sex-adjusted logistic regression analysis indicated that BMI obesity was associated with dyslipidemia (p=0.04), WC obesity was associated with dyslipidemia (p=0.07), and 'obesity' was associated with diabetes (p=0.06) and dyslipidemia (p=0.01). These results emphasize the importance of preventing obesity in Japan. Therefore, healthcare professionals should measure BMI and WC in order to enhance their assessment of cardiovascular risk.     

Estrogen and oxidative stress: A novel mechanism that may increase the risk for cardiovascular disease in women

Although early studies demonstrated that exogenous estrogen lowered a woman's risk of cardiovascular disease, recent trials indicate that HRT actually increases the risk of coronary heart disease or stroke. However, there is no clear explanation for this discrepancy. Is estrogen a helpful or a harmful hormone in terms of cardiovascular function? This review discusses some recent findings that propose a novel mechanism which may shed significant light upon this controversy. We propose that nitric oxide synthase (NOS) expressed within the vascular wall is a target of estrogen action. Under normal conditions in younger women, the primary product of estrogen action is NO, which produces a number of beneficial effects on vascular biology. As a woman ages, however, there is evidence for loss of important molecules essential for NO production (e.g., tetrahydrobiopterin, l-arginine). As these molecules are depleted, NOS becomes increasingly “uncoupled” from NO production, and instead produces superoxide, a dangerous reactive oxygen species. We propose that a similar uncoupling and reversal of estrogen response occurs in diabetes. Therefore, we propose that estrogen is neither “good” nor “bad”, but simply stimulates NOS activity. It is the biochemical environment around NOS that will determine whether estrogen produces a beneficial (NO) or deleterious (superoxide) product, and can account for this dual and opposite nature of estrogen pharmacology. Further, this molecular mechanism is consistent with recent analyses revealing that HRT produces salutary effects in younger women, but mainly increases the risk of cardiovascular dysfunction in older postmenopausal women.     

Alcohol consumption and its relation to cardiovascular risk factors in British women.

OBJECTIVE--To examine the relation between alcohol consumption and risk factors for coronary heart disease in women. DESIGN--Cross sectional study of a stratified random sample of the population grouped into five categories of habitual alcohol consumption. SETTING--People registered with general practitioners at two large health centres in east Bristol, England. SUBJECTS--1048 women aged 25-69 years. MAIN OUTCOME MEASURES--Fasting plasma concentrations of insulin, total cholesterol, total triglycerides, and high density lipoprotein cholesterol, including its subfractions HDL2 and HDL3, and body mass index. RESULTS--Compared with non-drinkers women consuming a moderate amount of alcohol (1-20 g/day) had lower plasma concentrations of triglycerides, by 0.19 mmol/l (95% confidence interval 0.07 to 0.35); cholesterol, by 0.4 mmol/l (0.19 to 0.61); and insulin, by 1.4 mU/l (0.43 to 1.97) and a lower body mass index, by 1.2 kg/m2 (0.43 to 1.97). They also had higher concentrations of high density lipoprotein cholesterol, by 0.09 mmol/l (0.03 to 0.15); HDL2 cholesterol by 0.05 mmol/l (-0.02 to 0.10) and HDL3 cholesterol, by 0.06 mmol/l (0.06 to 0.11). All these were independent of body mass index, smoking habits, and taking oral contraceptives. CONCLUSIONS--Moderate alcohol consumption is associated with lower levels of cardiovascular risk factors in women. Insulin may have a central role.