Gene by sex interaction in the etiology of coronary heart disease and the preceding metabolic syndrome

A comprehensive multi-task deep learning approach for predicting metabolic syndrome with genetic, nutritional, and clinical data

Metabolic syndrome (MetS) is a complex disorder characterized by a cluster of metabolic abnormalities, including abdominal obesity, hypertension, elevated triglycerides, reduced high-density lipoprotein cholesterol, and impaired glucose tolerance. It poses a significant public health concern, as individuals with MetS are at an increased risk of developing cardiovascular diseases and type 2 diabetes. Early and accurate identification of individuals at risk for MetS is essential. Various machine learning approaches have been employed to predict MetS, such as logistic regression, support vector machines, and several boosting techniques. However, these methods use MetS as a binary status and do not consider that MetS comprises five components. Therefore, a method that focuses on these characteristics of MetS is needed. In this study, we propose a multi-task deep learning model designed to predict MetS and its five components simultaneously. The benefit of multi-task learning is that it can manage multiple tasks with a single model, and learning related tasks may enhance the model's predictive performance. To assess the efficacy of our proposed method, we compared its performance with that of several single-task approaches, including logistic regression, support vector machine, CatBoost, LightGBM, XGBoost and one-dimensional convolutional neural network. For the construction of our multi-task deep learning model, we utilized data from the Korean Association Resource (KARE) project, which includes 352,228 single nucleotide polymorphisms (SNPs) from 7729 individuals. We also considered lifestyle, dietary, and socio-economic factors that affect chronic diseases, in addition to genomic data. By evaluating metrics such as accuracy, precision, F1-score, and the area under the receiver operating characteristic curve, we demonstrate that our multi-task learning model surpasses traditional single-task machine learning models in predicting MetS.

Trends of hypertensive heart disease prevalence and mortality in the United States between the period 1990-2019, Global burden of disease database

Hypertension presents a substantial cardiovascular risk, with poorly managed cases increasing the likelihood of hypertensive heart disease (HHD). This study examines individual-level trends and burdens of HHD in the US from 1990 to 2019, using the Global Burden of Disease (GBD) 2019 database. In 2019, HHD prevalence in the US reached 1,487,975 cases, with stable changes observed since 1990. Sex stratification reveals a notable increase in prevalence among females (AAPC 0.3, 95 % CI: 0.2 to 0.4), while males showed relative constancy (AAPC 0.0, 95 % CI: -0.1 to 0.1). Mortality rates totaled 51,253 cases in 2019, significantly higher than in 1990, particularly among males (AAPC 1.0, 95 % CI: 0.8 to 1.3). Younger adults experienced a surge in HHD-related mortality compared to older adults (AAPC 2.6 versus 2.0). These findings highlight the need for tailored healthcare strategies to address sex and age-specific disparities in managing HHD.

Genetic variations in ACE2 gene associated with metabolic syndrome in southern China: a case-control study

Metabolic syndrome (MetS) is closely related to cardiovascular and cerebrovascular diseases, and genetic predisposition is one of the main triggers for its development. To identify the susceptibility genes for MetS, we investigated the relationship between angiotensin-converting enzyme 2 (ACE2) single nucleotide polymorphisms (SNPs) and MetS in southern China. In total, 339 MetS patients and 398 non-MetS hospitalized patients were recruited. Four ACE2 polymorphisms (rs2074192, rs2106809, rs879922, and rs4646155) were genotyped using the polymerase chain reaction-ligase detection method and tested for their potential association with MetS and its related components. ACE2 rs2074192 and rs2106809 minor alleles conferred 2.485-fold and 3.313-fold greater risks of MetS in women. ACE2 rs2074192 and rs2106809 variants were risk factors for obesity, diabetes, and low-high-density lipoprotein cholesterolemia. However, in men, the ACE2 rs2074192 minor allele was associated with an approximately 0.525-fold reduction in MetS prevalence. Further comparing the components of MetS, ACE2 rs2074192 and rs2106809 variants reduced the risk of obesity and high triglyceride levels. In conclusion, ACE2 rs2074192 and rs2106809 SNPs were independently associated with MetS in a southern Chinese population and showed gender heterogeneity, which can be partially explained by obesity. Thus, these SNPs may be utilized as predictive biomarkers and molecular targets for MetS. A limitation of this study is that environmental and lifestyle differences, as well as genetic heterogeneity among different populations, were not considered in the analysis.

Genomic study of maternal lipid traits in early pregnancy concurs with four known adult lipid loci

BACKGROUND

Blood lipids during pregnancy are associated with cardiovascular diseases and adverse pregnancy outcomes. Genome-wide association studies (GWAS) in predominantly male European ancestry populations have identified genetic loci associated with blood lipid levels. However, the genetic architecture of blood lipids in pregnant women remains poorly understood.

OBJECTIVE

Our goal was to identify genetic loci associated with blood lipid levels among pregnant women from diverse ancestry groups and to evaluate whether previously known lipid loci in predominantly European adults are transferable to pregnant women.

METHODS

The trans-ancestry GWAS were conducted on serum levels of total cholesterol, high-density lipoprotein cholesterol (HDL), low-density lipoprotein cholesterol (LDL) and triglycerides during first trimester among pregnant women from four population groups (608 European-, 623 African-, 552 Hispanic- and 235 East Asian-Americans) recruited in the NICHD Fetal Growth Studies cohort. The four GWAS summary statistics were combined using trans-ancestry meta-analysis approaches that account for genetic heterogeneity among populations.

RESULTS

Loci in CELSR2 and APOE were genome-wide significantly associated (p-value < 5×10-8) with total cholesterol and LDL levels. Loci near CETP and ABCA1 approached genome-wide significant association with HDL (p-value = 2.97×10-7 and 9.71×10-8, respectively). Less than 20% of previously known adult lipid loci were transferable to pregnant women.

CONCLUSION

This trans-ancestry GWAS meta-analysis in pregnant women identified associations that concur with four known adult lipid loci. Limited replication of known lipid-loci from predominantly European study populations to pregnant women underlines the need for genomic studies of lipids in ancestrally diverse pregnant women.

CLINICAL TRIAL REGISTRATION

ClinicalTrials.gov, NCT00912132.

Sexual Differences in Genetic Predisposition of Coronary Artery Disease

BACKGROUND

The genomic structure that contributes to the risk of coronary artery disease (CAD) can be evaluated as a risk score of multiple variants. However, sex differences have not been fully examined in applications of genetic risk score (GRS) of CAD.

METHODS

Using data from the UK Biobank, we constructed a CAD-GRS based on all known loci, 3 mediating trait-based (blood pressure, lipids, and body mass index) subscores, and a genome-wide polygenic risk score based on 1.1 million variants. The differences in genetic associations with prevalent and incident CAD between men and women were investigated among 317 509 unrelated individuals of the European ancestry. We also assessed interactions with sex for 161 individual loci included in the comprehensive GRS.

RESULTS

For both prevalent and incident CAD, the associations of comprehensive and genome-wide GRSs were stronger among men than women. Using a score of 161 loci, we observed a 2.4× higher risk for incident CAD comparing men with high genetic risk to men with low genetic risk but an 80% greater risk comparing women with high genetic risk to women with low genetic risk (interaction P=0.002). Of the 3 subscores, the blood pressure-associated subscore exhibited sex differences (interaction P=0.0004 per SD increase in subscore). Analysis of individual variants identified a novel gene-sex interaction at locus 21q22.11.

CONCLUSIONS

Sexual differences in genetic predisposition should be considered in future studies of CAD, and GRSs should not be assumed to perform equally well in men and women.

Body Fat Mass, Fat Distribution and Egg Consumption: a Population-Based Study in Chinese Adults

Objective: Egg is the vital source for many nutrients. The present study aimed to evaluate how egg consumption contributes to body fat mass and fat distribution in general Chinese adults.Methods: In a representative study of Chinese adults, 2241 rural adults aged 18-80 years completed physical measurements and semi quantitative food frequency questionnaire (FFQ). Body fat percentage (BF%) was estimated through validated Chinese-specific equations including age, body mass index (BMI), waist circumference (WC), gender and their interaction.Results: The prevalence of excessive body fat and central obesity in males were 44.2% and 31.3%, lower than that in females (60.7% and 36.1%, p < 0.05). 37.3% of lean or normal-weight individuals by BMI experienced excessive body fat given their BF% and 43.5% were central obesity according to WC. In females, egg consumption was associated with better body fat mass and its distribution. Compared with non-consumers, individuals consumed egg >50 g/d had a 34% lower risk of central obesity (OR:0.66, 0.39-0.99) and 38% lower risk of excessive body fat (OR:0.62, 0.37-1.00). There were significant dose-response relationships between egg consumption and overweight with excessive body fat/central obesity (p for linear trend <0.05). However, these associations were not significant in males.Conclusion: Our findings underscore the necessity for future public health guidelines to assess body fat mass and distribution simultaneously in Chinese adults. Egg consumption might be beneficial for weight regulation, especially for overweight with excessive body fat/central obesity in females. Further research is warrant to establish the causal inference.

Heritable traits that contribute to nephrolithiasis

Urinary stones tend to cluster in families. Of the known risk factors, evidence is strongest for heritability of urinary calcium excretion. Recent studies suggest that other stone risk factors may have heritable components including urinary pH, citrate and magnesium excretion, and circulating vitamin D concentration. Several risk factors assumed purely environmental may also have heritable components, including dietary intake and thirst. Thus, future studies may reveal that genetics plays an even stronger role in urinary stone pathogenesis than previously known.

Effect of B Vitamins from Diet on Hypertension

BACKGROUND

In western populations, a higher level of dietary B vitamins intake has been associated with a lower risk of hypertension. However, data in Chinese is limited, whose B vitamins consumption is low and rates of hypertension are high.

AIM OF THE STUDY

To investigate whether the three B vitamins are associated with hypertension in rural Chinese.

METHODS

Cross-sectional survey among 2241 rural Chinese aged 18-80 years was conducted in northwestern China in 2010. Blood pressure was measured by trained medical staff and dietary nutrients were assessed with a semiquantitative food frequency questionnaire.

RESULTS

592 cases of hypertension were newly diagnosed. The deficiency proportions were 20.5% for vitamin B-6, 43.9% for folate and 98.5% for B-12. For females, participants in the highest quartile of B-6 intake had a significantly lower risk of hypertension (OR = 0.69; 95% CI: 0.50-0.93; p for trend <0.05). For males, the multivariable OR for the same comparison was 0.75 (95% CI: 0.56-0.99, p for trend >0.05). No significant associations were observed between B-12, folate intake and hypertension. For females, the highest quartile of both folate and B-6 intake was associated with a reduced risk of hypertension (OR = 0.53; 95% CI: 0.29-0.89), compared with in the middle quartile of both vitamins.

CONCLUSIONS

Higher intake of vitamin B-6 is independently associated with lower risk of hypertension in Chinese rural adults. Among females with high folate intake, the association between B-6 and hypertension was strongest. Additional studies are warrant to establish the causal inference.

Sex-specific effect of CPB2 Ala147Thr but not Thr325Ile variants on the risk of venous thrombosis: A comprehensive meta-analysis

BACKGROUND

Thrombin activatable fibrinolysis inhibitor (TAFI), encoded by the Carboxypeptidase B2 gene (CPB2), is an inhibitor of fibrinolysis and plays a role in the pathogenesis of venous thrombosis. Experimental findings support a functional role of genetic variants in CPB2, while epidemiological studies have been unable to confirm associations with risk of venous thrombosis. Sex-specific effects could underlie the observed inconsistent associations between CPB2 genetic variants and venous thrombosis.

METHODS

A comprehensive literature search was conducted for associations between Ala147Thr and Thr325Ile variants with venous thrombosis. Authors were contacted to provide sex-specific genotype counts from their studies. Combined and sex-specific random effects meta-analyses were used to estimate a pooled effect estimate for primary and secondary genetic models.

RESULTS

A total of 17 studies met the inclusion criteria. A sex-specific meta-analysis applying a dominant model supported a protective effect of Ala147Thr on venous thrombosis in females (OR = 0.81, 95%CI: 0.68,0.97; p = 0.018), but not in males (OR = 1.06, 95%CI:0.96-1.16; p = 0.263). The Thr325Ile did not show a sex-specific effect but showed variation in allele frequencies by geographic region. A subgroup analysis of studies in European countries showed decreased risk, with a recessive model (OR = 0.83, 95%CI:0.71-0.97, p = 0.021) for venous thrombosis.

CONCLUSIONS

A comprehensive literature review, including unpublished data, provided greater statistical power for the analyses and decreased the likelihood of publication bias influencing the results. Sex-specific analyses explained apparent discrepancies across genetic studies of Ala147Thr and venous thrombosis. While, careful selection of genetic models based on population genetics, evolutionary and biological knowledge can increase power by decreasing the need to adjust for testing multiple models.

The effect of mobile phone short messaging system on healthy food choices among Iranian postmenopausal women

Introduction:

Central adiposity and metabolic syndrome are quite common among postmenopausal women. Dietary diversity and healthy food choices have essential role in health and also in prevention of obesity. The main objective of this study was to evaluate the impact of mobile phone short messaging system on healthy food choices among Iranian postmenopausal women.

Materials and Methods:

This was a randomized controlled trial in which 100 postmenopausal women aged 40-60 years were recruited and assigned to two groups (50 each in the intervention and control groups). Food frequency consumption was measured using a questionnaire. A total of 16 text messages including information about modification of food selection (healthy choices, benefits, methods, etc.,) were sent to participants in the intervention group during 4 months follow-up (1/week). The Chi-square and independent t-test used for data analysis. Ninety-two women completed the study.

Results:

The consumption of Vitamin A rich fruits and vegetables significantly increased in the intervention group compared to the control group (P < 0.001). More women in the intervention group consumed fish after intervention (P = 0.02). The consumption of green leafy vegetables showed a nonsignificant increase in the intervention group.

Conclusion:

Using mobile phone short messaging system can improve the healthy food choices regarding Vitamin A rich fruits and vegetables and fish among postmenopausal women.

Heritability of metabolic syndrome traits in a large population-based sample

Heritability estimates of metabolic syndrome traits vary widely across studies. Some studies have suggested that the contribution of genes may vary with age or sex. We estimated the heritability of 11 metabolic syndrome-related traits and height as a function of age and sex in a large population-based sample of twin families (N = 2,792-27,021, for different traits). A moderate-to-high heritability was found for all traits [from H(2) = 0.47 (insulin) to H(2) = 0.78 (BMI)]. The broad-sense heritability (H(2)) showed little variation between age groups in women; it differed somewhat more in men (e.g., for glucose, H(2) = 0.61 in young females, H(2) = 0.56 in older females, H(2) = 0.64 in young males, and H(2)= 0.27 in older males). While nonadditive genetic effects explained little variation in the younger subjects, nonadditive genetic effects became more important at a greater age. Our findings show that in an unselected sample (age range, ~18-98 years), the genetic contribution to individual differences in metabolic syndrome traits is moderate to large in both sexes and across age. Although the prevalence of the metabolic syndrome has greatly increased in the past decades due to lifestyle changes, our study indicates that most of the variation in metabolic syndrome traits between individuals is due to genetic differences.

Association between dietary protein intake and the risk of hypertension: a cross-sectional study from rural western China

Evidence for an association between dietary proteins and the risk of hypertension in rural Chinese adults, whose diets are protein-poor and unbalanced, is limited. The aim of this study was to investigate the effect of dietary proteins on hypertension among adults of rural western China. A cross-sectional survey was conducted in Hanzhong, China, and 2241 residents were included in the analysis. Logistic regression models were used to examine whether dietary proteins (total, plant and animal protein) were independently correlated with hypertension. The total protein intake was inadequate (51.7 g per day for male and 40.1 g per day for female), accounting for 56-71% of the Chinese recommended nutrient intakes or adequate intakes. Nearly 80% of protein intake derived from plants, especially grains, and the proportion derived from plants was higher in females than in males. The daily animal protein intake was 12.1 g for males and 8.3 g for females. For females, no significant association was found between hypertension and total protein or plant protein intake. However, animal protein intake was significantly and negatively associated with the risk of hypertension after controlling for demographic characteristics, lifestyle factors, body mass index and other dietary nutrients. In addition, the odds ratio for the upper quartile compared with the bottom quartile was 0.64 (95% confidence interval, CI: 0.43-0.95, P for trend <0.05). Furthermore, a significant decrease of 1.082 mm Hg (95%CI: 0.189-1.975) in systolic blood pressure and 0.668 mm Hg (95%CI: 0.105-1.232) in diastolic blood pressure was observed per s.d. increase of animal protein intake in females. For males, we did not observe a significant association between dietary proteins and hypertension or blood pressure. In conclusion, for the western rural Chinese population, especially women, whose dietary protein intake is low and largely derived from plants, the intake of animal protein may be related to a decreased risk of hypertension.

Sex differences in age-related cardiovascular mortality

Introduction

Sex-related physiological differences result in different expressions of diseases for men and women. Data are contradicting regarding the increase in the female risk for cardiovascular disease (CVD) at mid-life. Thus, we studied possible sex differences in age-adjusted mortality for CVD and non-vascular diseases stratifying our findings by specific age groups.

Methods

Over one million deaths (1 080 910) reported to the Finnish nationwide Causes of Death Register in 1986–2009 were analyzed. A total of 247 942 male deaths and 278 752 female deaths were of CVD origin, the remaining deaths were non-vascular. The annual mortality rates were calculated per 100 000 mid-year population, separately for men and women in 5-year age categories.

Results

The age-standardized risk of death from CVD was 80% higher for men (442/100 000) than for women (246/100 000). After age 45–54 the male CVD mortality rate elevated parallel to the non-vascular mortality, whereas in women the CVD mortality elevated considerably more rapidly than the non-vascular mortality from age 60 years onwards.

Conclusions

Heart disease mortality in men accelerates at a relatively young age, but in women the risk shows a steep increase at approximately 60 years of age. These data emphasize the need to identify and prevent risk factors for CVD, especially in women in their mid-life years.

Development and evaluation of a genetic risk score for obesity

Multi-locus profiles of genetic risk, so-called "genetic risk scores," can be used to translate discoveries from genome-wide association studies into tools for population health research. We developed a genetic risk score for obesity from results of 16 published genome-wide association studies of obesity phenotypes in European-descent samples. We then evaluated this genetic risk score using data from the Atherosclerosis Risk in Communities (ARIC) cohort GWAS sample (N = 10,745, 55% female, 77% white, 23% African American). Our 32-locus GRS was a statistically significant predictor of body mass index (BMI) and obesity among ARIC whites [for BMI, r = 0.13, p<1 × 10(-30); for obesity, area under the receiver operating characteristic curve (AUC) = 0.57 (95% CI 0.55-0.58)]. The GRS predicted differences in obesity risk net of demographic, geographic, and socioeconomic information. The GRS performed less well among African Americans. The genetic risk score we derived from GWAS provides a molecular measurement of genetic predisposition to elevated BMI and obesity.[Supplemental materials are available for this article. Go to the publisher's online edition of Biodemography and Social Biology for the following resource: Supplement to Development & Evaluation of a Genetic Risk Score for Obesity.].

Oxidative stress and metabolic syndrome in a Japanese female population

AIM

One of the methods to evaluate oxidative stress in clinical medical settings is the reactive oxygen metabolites (d-ROMs) test. While metabolic syndrome (MetS) is considered an oxidative condition, the oxidative status in MetS has not been fully examined using this test. The aim of the present study was to investigate the possible association between oxidative stress as evaluated by the d-ROMs test and the MetS component number, in a Japanese female population.

METHODS

The serum oxidant capacity (measured by the d-ROMs test) was cross-sectionally determined in cardiovascular disease-free and non-smoking women who were not taking medications (n = 180; mean age, 60 ± 10 (standard deviation) years). Their MetS state was determined by the National Cholesterol Education Program Adult Treatment Panel recommendations with minor modifications for a Japanese population.

RESULTS

Patients with MetS (n = 60, 362 ± 53 CARR U) showed a significantly higher oxidant capacity by d-ROMs than those without MetS (n = 120, 324 ± 55 CARR U, P < 0.01). Moreover, the significant increase in the oxidant capacity by d-ROMs was closely associated with an increase in the MetS component number (trend P < 0.01).

CONCLUSIONS

These results showed a significantly positive association between the oxidant capacity (by d-ROMs) and the MetS component number in this population. Further studies are required to establish the clinical applications of this test to MetS practice and clarify the biological mechanisms of the observed relationships.

Type 2 diabetes and cardiovascular diseases: do they share a common soil? The Asian Indian experience

In India, diabetes and cardiovascular disease (CVD) are growing health problems. CVD accounts for much of the increased morbidity and premature mortality associated with type 2 diabetes. Moreover, CVD also occurs 2-3 decades earlier among diabetic subjects and runs a more aggressive course and has a worse prognosis. The pathophysiology of the link between diabetes and CVD is complex and multifactorial and understanding the mechanisms of the disease can help identify and treat CVD in patients with diabetes and vice versa. The current article reviews the common antecedents between type 2 diabetes and CVD including non-modifiable and modifiable risk factors and suggests that future research on diabetes and CVD should focus on searching for risk factors for CVD that may be more specific to diabetes, such as hypoglycaemia or medication related comorbidities. Also, the authors recommend research on common genetic variants which might have stronger effects and hence have a potential role in diabetes and CVD risk prediction. Finally, primary prevention trials trying to prevent both diabetes and CVD are the urgent need of the hour!

Genetic variation within the TRPM5 locus associates with prediabetic phenotypes in subjects at increased risk for type 2 diabetes

The functional knockout of the calcium-sensitive, nonselective cation channel TRPM5 alters glucose-induced insulin secretion and glucose tolerance. We hypothesized that genetic variation in the TRPM5 gene may contribute to prediabetic phenotypes, including pancreatic β-cell dysfunction. We genotyped 1798 white subjects at increased type 2 diabetes mellitus risk for 9 TRPM5 single nucleotide polymorphisms (namely, rs2301696, rs800344, rs800345, rs800347, rs800348, rs2074234, rs2301698, rs886277, and rs2301699) and also performed correlational analyses with metabolic traits. An oral glucose tolerance test (OGTT) was conducted on all subjects, and a subset (n = 525) additionally underwent a hyperinsulinemic-euglycemic clamp. The 9 chosen single nucleotide polymorphisms cover 100% of the common genetic variation (minor allele frequency ≥0.05) within the TRPM5 locus (D' = 1.0; r² ≥ 0.8). Rs800344, rs800345, and rs2301699 were significantly associated with area under the curve (AUC) glucose during the OGTT in the additive and dominant models after adjustment for sex, age, and body mass index (all Ps ≤ .0025). Furthermore, rs800344 was significantly associated with 2-hour glucose in the dominant model (P = .0009). After stratification for sex, rs2301699 was significantly associated with the ratio of AUC insulin 0 to 30 minutes to AUC glucose 0 to 30 minutes in women (P = .0097), but not in men (P = .3), in the dominant model. Female minor allele carriers of rs2301699 showed significantly lower glucagon-like peptide-1 levels at 30 minutes during the OGTT compared with major allele homozygotes (P = .0124), whereas in male subjects, no significant differences were found (P = .3). In our German population, the common TRPM5 variants are likely to be associated with prediabetic phenotypes; and this may in turn contribute to the development of type 2 diabetes mellitus.

A QTL for genotype by sex interaction for anthropometric measurements in Alaskan Eskimos (GOCADAN Study) on chromosome 19q12-13

Variation in anthropometric measurements due to sexual dimorphism can be the result of genotype by sex interactions (G×S). The purpose of this study was to examine the sex-specific genetic architecture in anthropometric measurements in Alaskan Eskimos from the Genetics of Coronary Artery Disease in Alaska Natives (GOCADAN) study. Maximum likelihood-based variance components decomposition methods, implemented in SOLAR, were used for G×S analyses. Anthropometric measurements included BMI, waist circumference (WC), waist/height ratio, percent body fat (%BF), and subscapular and triceps skinfolds. Except for WC, mean values of all phenotypes were significantly different in men and women (P < 0.05). All anthropometric measures were significantly heritable (P < 0.001). In a preliminary analysis not allowing for G×S interaction, evidence of linkage was detected between markers D19S414 and D19S220 on chromosome 19 for WC (logarithm of odds (lod) = 3.5), %BF (lod = 1.7), BMI (lod = 2.4), waist/height ratio (lod = 2.5), subscapular (lod = 2.1), and triceps skinfolds (lod = 1.9). In subsequent analyses which allowed for G×S interaction, linkage was again found between these traits and the same two markers on chromosome 19 with significantly improved lod scores for: WC (lod = 4.5), %BF (lod = 3.8), BMI (lod = 3.5), waist/height ratio (lod = 3.2), subscapular (lod = 3.0), and triceps skinfolds (lod = 2.9). These results support the evidence of a G×S interaction in the expression of genetic effects resulting in sexual dimorphism in anthropometric phenotypes and identify the chromosome 19q12-13 region as important for adiposity-related traits in Alaskan Eskimos.

Frequency of citrus fruit intake is associated with the incidence of cardiovascular disease: the Jichi Medical School cohort study

Background

It has been reported that fruit intake protects against cardiovascular disease (CVD). However, most of the relevant studies were conducted in Western countries, and only a few investigated Japanese populations. The present cohort study assessed the effect of citrus fruit intake on the incidence of CVD and its subtypes in a Japanese population.

Methods

A baseline examination consisting of physical and blood examinations and a self-administered questionnaire was conducted during the period from April 1992 through July 1995. Dietary habits were assessed using a food frequency questionnaire that was divided into 5 categories. Citrus fruit was examined separately due to its frequent consumption by the general Japanese population. Using the Cox proportional hazards model, data from 10 623 participants (4147 men, 6476 women) who had no history of CVD or carcinoma were analyzed to assess the association between frequency of citrus fruit intake and CVD incidence.

Results

Frequent intake of citrus fruit was associated with a lower incidence of CVD: the hazard ratio for almost daily intake versus infrequent intake of citrus fruit was 0.57 (95% confidence interval: 0.33–1.01, P for trend = 0.04) in men and 0.51 (0.29–0.88, P for trend = 0.02) in women. Frequent intake of citrus fruit was also associated with lower incidences of both all stroke and cerebral infarction, but not hemorrhagic stroke or myocardial infarction.

Conclusions

Frequent intake of citrus fruit may reduce the incidence of CVD, especially cerebral infarction, in men and women.

The genetics of obesity and the metabolic syndrome

In this review, we discuss the genetic architecture of obesity and the metabolic syndrome, highlighting recent advances in identifying genetic variants and loci responsible for a portion of the variation in components of the metabolic syndrome, namely, adiposity traits, serum HDL and triglycerides, blood pressure, and glycemic traits. We focus particularly on recent progress from large-scale genome-wide association studies (GWAS), by detailing their successes and how lessons learned can pave the way for future discovery. Results from recent GWAS coalesce with earlier work suggesting numerous interconnections between obesity and the metabolic syndrome, developed through several potentially pleiotropic effects. We detail recent work by way of a case study on the cadherin 13 gene and its relation with adiponectin in the HyperGEN and the Framingham Heart Studies, and its association with obesity and the metabolic syndrome. We provide also a gene network analysis of recent variants related to obesity and metabolic syndrome discovered through genome-wide association studies, and 4 gene networks based on searching the NCBI database.

Evaluating gene by sex and age interactions on cardiovascular risk factors in Brazilian families

BACKGROUND

In family studies, it is important to evaluate the impact of genes and environmental factors on traits of interest. In particular, the relative influences of both genes and the environment may vary in different strata of the population of interest, such as young and old individuals, or males and females.

METHODS

In this paper, extensions of the variance components model are used to evaluate heterogeneity in the genetic and environmental variance components due to the effects of sex and age (the cutoff between young and old was 43 yrs). The data analyzed were from 81 Brazilian families (1,675 individuals) of the Baependi Family Heart Study.

RESULTS

The models allowing for heterogeneity of variance components by sex suggest that genetic and environmental variances are not different in males and females for diastolic blood pressure, LDL-cholesterol, and HDL-cholesterol, independent of the covariates included in the models. However, for systolic blood pressure, fasting glucose and triglycerides, the evidence for heterogeneity was dependent on the covariates in the model. For instance, in the presence of sex and age covariates, heterogeneity in the genetic variance component was suggested for fasting glucose. But, for systolic blood pressure, there was no evidence of heterogeneity in any of the two variance components. Except for the LDL-cholesterol, models allowing for heterogeneity by age provide evidence of heterogeneity in genetic variance for triglycerides and systolic and diastolic blood pressure. There was evidence of heterogeneity in environmental variance in fasting glucose and HDL-cholesterol.

CONCLUSIONS

Our results suggest that heterogeneity in trait variances should not be ignored in the design and analyses of gene-finding studies involving these traits, as it may generate additional information about gene effects, and allow the investigation of more sophisticated models such as the model including sex-specific oligogenic variance components.

Schizophrenia: women bear a disproportionate toll of antipsychotic side effects

BACKGROUND

Men and women with schizophrenia suffer not only from their illness but also from the side effects of their medications.

OBJECTIVE

To review the toll of antipsychotic side effects specifically on women.

STUDY DESIGN

A review of the literature in the PubMed database since 1990 using search terms: sex difference, antipsychotics, schizophrenia, pharmacokinetics, pharmacodynamics, and pharmacogenomics and retrieving additional publications from the reference lists of the original articles.

RESULTS

Findings suggest that, because of differing pharmacokinetics, women are more vulnerable than men to weight gain secondary to antipsychotics and to the consequences (metabolic, cardiovascular, reproductive) of weight gain. They are also more vulnerable to hyperprolactinemia and QTc prolongation.

CONCLUSIONS

Dosing guidelines need to be critically appraised. The greater toll of side effects in women may undermine adherence to prescribed treatments, add to the stigma that attaches to mental illness, and diminish the quality of women's lives. Side effects increase the cost of mental illness and heighten the burden experienced by caregivers. They exacerbate morbidity and raise mortality rates. They affect the children of women treated with antipsychotic medication.

The association between metabolic syndrome and coronary artery disease in Jordan

BACKGROUND

Previous studies in Jordan showed a considerably high prevalence of metabolic syndrome (MeS) and its individual components. However, data about the association between MeS and coronary artery disease (CAD) in Jordan are lacking. Therefore, this study aimed to determine the association between MeS and CAD among Jordanians.

METHODS

This case-control study included 269 patients diagnosed with CAD and 1026 subjects without CAD. Data collected from cases and controls included socio-demographic and clinical characteristics and anthropometric measurements. Patients were diagnosed with MeS based on the criteria of the National Cholesterol Education Program (NCEP) adult treatment panel (ATP) III.

RESULTS

MeS was present in 65.1% of patients with CAD and in 44.0% of those with no CAD (p<0.0005). After adjusting for the important variables in the multivariate analysis, those with MeS were twice more likely to have CAD (OR = 1.94, 95% CI: 1.29, 2.93, p = 0.002) compared to those without MeS. The number of metabolic abnormalities was significantly associated with CAD, when it substituted MeS in the regression model, with a higher number of MeS components led to greater odds for CAD.

CONCLUSIONS

The MeS, which occurs very frequently in the general population, is associated with CAD in Jordan. The identification of subjects with the MeS is conceivably useful from a clinical standpoint, as it can be anticipated that these individuals should benefit from interventions aimed at reducing cardiovascular risk.

Secondary effects of antipsychotics: women at greater risk than men

CONTEXT

The health burden of antipsychotic medication is well known, but the disproportionate effect on women as compared with men is underappreciated.

OBJECTIVE

The goal of this article is preventive--to better inform clinicians so that the risks to women and to their offspring can be diminished.

METHOD

All PubMed sources in which the search term gender (or sex) was linked to a side effect of antipsychotic medication were reviewed.

RESULT

There is general agreement in the literature on women's increased susceptibility to weight gain, diabetes, and specific cardiovascular risks of antipsychotics, with less consensus on malignancy risks and risks to the fetus. Cardiovascular death, to which men are more susceptible than women, is disproportionately increased in women by the use of antipsychotics. Sedating antipsychotics raise the risk of embolic phenomena during pregnancy, and postpartum. Prolactin-elevating drugs suppress gonadal hormone secretion and may enhance autoimmune proclivity.

CONCLUSIONS

Clinicians need to be aware of the differential harm that women (and their offspring) can incur from the side effects of antipsychotics.

Major depression and coronary artery disease in the Swedish twin registry: phenotypic, genetic, and environmental sources of comorbidity

CONTEXT

Major depresssion (MD) and coronary artery disease (CAD) frequently co-occur. The mechanisms of comorbidity are uncertain.

OBJECTIVE

To clarify sources of MD-CAD comorbidity.

DESIGN

Major depression was assessed at the time of the personal interview, and CAD from hospital discharge records and death certificates.

SETTING

Swedish population-based twin registry.

PARTICIPANTS

The study included 30 374 twins with a mean age of 57 years. Main Outcome Measure Modified DSM-IV diagnosis of MD or diagnosis of CAD.

RESULTS

Lifetime association between MD and CAD was modest (odds ratio, approximately 1.3). In time-dependent Cox analyses, onset of CAD produced concurrent and ongoing hazard ratios for MD of 2.83 and 1.75. These risks increased if the diagnosis of CAD was restricted to myocardial infarction. Onset of MD increased the concurrent and ongoing hazard ratios for CAD to 2.53 and 1.17. The ongoing CAD risk was strongly associated with depressive severity and recurrence. Twin models showed that the modest comorbidity between MD and CAD in women arose primarily from shared genetic effects, although the genetic correlation was small (+0.16). In men, the source of comorbidity was moderated by age, being environmental in older members and largely genetic in younger members of the sample.

CONCLUSIONS

Although the MD-CAD relationship across the lifespan is modest, time-dependent models reveal stronger associations. The sustained effect of CAD onset on MD risk is much stronger than vice versa. The effect of MD on CAD is largely acute, and the longer-term effects are apparently mediated via depressive recurrence. When examined separately, in men, environmental effects, which are often acute, play a large role in MD-CAD comorbidity, whereas in women, chronic effects, which are in part genetic, are more important. In men, genetic sources of MD-CAD comorbidity are more important in younger members of the sample.

Common variants of four bilirubin metabolism genes and their association with serum bilirubin and coronary artery disease in Chinese Han population

OBJECTIVES

Studies have revealed an inverse relationship between serum total bilirubin (TBIL) levels and coronary artery disease (CAD). This study investigated the genetic variants of four bilirubin metabolism genes--heme oxygenase-1 (HMOX1), biliverdin reductase A (BLVRA), solute carrier organic anion transporter family member 1B1 (SLCO1B1), and uridine diphosphate glycosyltransferase 1A1 (UGT1A1)--in relation to TBIL levels and CAD.

METHODS AND RESULTS

Thirty-five common single nucleotide polymorphisms (SNPs) were genotyped in 2380 unrelated Han participants who underwent angiocardiography at hospitals in Shanghai, China. Only three genetic variants--rs4399719 (UGT1A1 T-2473G), rs887829 (UGT1A1 G-364A), and rs4148323 (UGT1A1 G211A)--were associated with TBIL levels (each P<0.001). Four significant associations with CAD were detected after controlling age and the false discovery rate at 15%: the recessive effect of SNP rs887829 (UGT1A1 G-364A) [age-adjusted odds ratio (OR): 0.24; 95% confidence interval (CI): 0.10-0.60; P=0.0014] and dominant effect of rs4149013 (SLCO1B1 A-12099G) (age-adjusted OR: 0.70; 95% CI: 0.55-0.91; P=0.0069) on male CAD, and the additive effects of rs2877262 (BLVRA G+1238/in6C) (age-adjusted OR: 0.73; 95% CI: 0.59-0.89; P=0.0021) and rs2690381 (BLVRA G+2613/in6A) (age-adjusted OR: 0.70; 95% CI: 0.56-0.86; P=0.0008) on female CAD. SNPs rs2877262 and rs2690381 were both in a linkage disequilibrium block within BLVRA with r greater than 0.750. Correspondingly, this block was identified to be associated with female CAD.

CONCLUSION

Our study provides genetic evidences for the difference in the impact of these four bilirubin metabolism genes on TBIL levels and CAD.

Gender differences in genetic risk profiles for cardiovascular disease

BACKGROUND

Cardiovascular disease (CVD) incidence, complications and burden differ markedly between women and men. Although there is variation in the distribution of lifestyle factors between the genders, they do not fully explain the differences in CVD incidence and suggest the existence of gender-specific genetic risk factors. We aimed to estimate whether the genetic risk profiles of coronary heart disease (CHD), ischemic stroke and the composite end-point of CVD differ between the genders.

METHODOLOGY/PRINCIPAL FINDINGS

We studied in two Finnish population cohorts, using the case-cohort design the association between common variation in 46 candidate genes and CHD, ischemic stroke, CVD, and CVD-related quantitative risk factors. We analyzed men and women jointly and also conducted genotype-gender interaction analysis. Several allelic variants conferred disease risk for men and women jointly, including rs1801020 in coagulation factor XII (HR = 1.31 (1.08-1.60) for CVD, uncorrected p = 0.006 multiplicative model). Variant rs11673407 in the fucosyltransferase 3 gene was strongly associated with waist/hip ratio (uncorrected p = 0.00005) in joint analysis. In interaction analysis we found statistical evidence of variant-gender interaction conferring risk of CHD and CVD: rs3742264 in the carboxypeptidase B2 gene, p(interaction) = 0.009 for CHD, and rs2774279 in the upstream stimulatory factor 1 gene, p(interaction) = 0.007 for CHD and CVD, showed strong association in women but not in men, while rs2069840 in interleukin 6 gene, p(interaction) = 0.004 for CVD, showed strong association in men but not in women (uncorrected p-values). Also, two variants in the selenoprotein S gene conferred risk for ischemic stroke in women, p(interaction) = 0.003 and 0.007. Importantly, we identified a larger number of gender-specific effects for women than for men.

CONCLUSIONS/SIGNIFICANCE

A false discovery rate analysis suggests that we may expect half of the reported findings for combined gender analysis to be true positives, while at least third of the reported genotype-gender interaction results are true positives. The asymmetry in positive findings between the genders could imply that genetic risk loci for CVD are more readily detectable in women, while for men they are more confounded by environmental/lifestyle risk factors. The possible differences in genetic risk profiles between the genders should be addressed in more detail in genetic studies of CVD, and more focus on female CVD risk is also warranted in genome-wide association studies.

Association between lipid profile and circulating concentrations of estrogens in young men

OBJECTIVES

Men show higher rates of cardiovascular morbidity and mortality than pre-menopausal women and this sexual dimorphism may be related to sex-specific effects of sex steroids on cardiovascular risk factors. Unlike androgens, estrogens were not extensively investigated in relation to cardiovascular phenotypes in men.

METHODS

We examined associations of estradiol and estrone and their precursors (total testosterone and androstenedione) with traditional cardiovascular risk factors (lipids, blood pressure, body mass) in 933 young (median age: 19 years), apparently healthy Polish men.

RESULTS

Total estradiol was associated with total cholesterol (p=0.006) and high-density lipoprotein cholesterol (HDL-C) (p<0.001) and estrone showed the strongest associations with both total cholesterol (p<0.001) and low-density lipoprotein cholesterol (LDL-C) (p<0.001) in the unadjusted ANOVA analysis. In the multivariable adjusted models in which other independent variables were held as constant one standard deviation increase in estradiol level was associated with 6%-standard deviation increase in total cholesterol (standardized beta=0.06, p=0.038) and 6%-standard deviation decrease in HDL-cholesterol (standardized beta=-0.06, p=0.036). An increase in estrone levels by one standard deviation was associated with respective 12%- and 13%-standard deviation increases in total cholesterol (standardized beta=0.12, p<0.001) and LDL-cholesterol levels (standardized beta=0.12, p<0.001) after controlling for other predictors of lipids. Estrone correlated linearly with androstenedione (r=0.28, p<0.001) but there was no correlation between estradiol and testosterone. Estrogens retained their independent associations with lipids after adjustment for their biochemical precursors in the multivariable analysis.

CONCLUSIONS

Increased levels of estrogens are associated with unfavourable lipid profile in men and this association is present early in life, before apparent manifestations of cardiovascular disease.

Fruit and vegetable intake and mortality from cardiovascular disease are inversely associated in Japanese women but not in men

Some epidemiological studies undertaken in Western countries have demonstrated that high intake of fruit and vegetables results in decreased risk of cardiovascular disease (CVD). The objective of this study was to examine the hypothesis that high intake of fruit and vegetables lowers CVD mortality in a population-based cohort of Japanese subjects. In 1992, fruit and vegetable intake was assessed in 13,355 men and 15,724 women in Takayama, Gifu, Japan using a validated FFQ. During the follow-up (1992-99), 200 men and 184 women died from CVD. For women, the highest quartile of vegetable intake compared with the lowest was marginally significant and inversely associated with CVD mortality after adjusting for total energy, age, and nondietary and dietary covariates [hazard ratio (HR) = 0.62; 95% CI, 0.36-1.08; P-trend = 0.007]. An inverse trend with borderline significance was also observed in fruit intake, excluding CVD deaths in the first 2 y of this study, after adjusting for the above-mentioned covariates (HR = 0.83; 95% CI, 0.51-1.34; P-trend = 0.10). In men, CVD death was not associated with fruit (HR = 1.16; 95% Cl, 0.77-1.74; P-trend = 0.61) and vegetable (HR = 0.81, 95% CI: 0.49-1.34; P-trend = 0.47) intake. These data suggest that higher intake of vegetables is associated with reduced risk of death from CVD for women.

Gaining weight and components of metabolic syndrome in the period of menopause

INTRODUCTION Menopause induces redistribution of fat mass and development of abdominal obesity, increasing risk for metabolic syndrome (MS) by 60%. Related cardiovascular diseases become a leading cause of morbidity and mortality in women after fifty years of age. OBJECTIVE The aim of this study was to investigate the influence of gaining weight on components of MS in the menopause. METHOD The study included 50 obese women, BMI=31.92? 5.83 kg/m2, age 54.40?3.64, time since menopause 5.90?5.46 years, and 37 normal weight women, BMI=23.50?2.13 kg/m2, age 53.92?3.95, time since menopause 5.96?4.92 years. Both groups were divided according to the presence of MS into two subgroups. Anthropometric characteristics and blood pressure were measured. Blood was taken at 8 am for the following: fasting glucose, triglycerides, cholesterol, HDL, LDL, apolipoprotein A (ApoA), apolipoprotein B (ApoB), lipoprotein(a) (Lp(a)), C-reactive protein (CRP), fibrinogen, FSH, LH, prolactin, oestrogen, progesterone, testosterone and sex hormonebinding globulin (SHBG). RESULTS 66% of obese women had MS compared with 22% normal weight women. Significant differences between groups were found for the following: weight, BMI, waist, hip circumference, waist/hip ratio, diastolic blood pressure, Lp(a), FSH, LH, prolactin (all p<0.01) and fasting glucose (p<0.05). Obese women with and without MS were significantly diverse for the following: waist/hip ratio, systolic blood pressure and fasting glucose (all p<0.01); age, BMI, waist circumference, triglycerides, HDL, Lp(a) and SHBG (all p<0.05). Normal weight women with and without MS had significantly different values of waist/hip ratio, systolic, diastolic blood pressure, triglycerides (all p<0.01); HDL and testosterone (p<0.05). Significant differences were found between obese and normal weight women with MS in anthropometric characteristics, ApoA, Lp(a), fibrinogen (all p<0.01) and FSH (p<0.05). CONCLUSION Abdominal obesity significantly increases incidence of MS as a cluster of cardiovascular risk factors in the menopause.