Impact of visceral fat on blood pressure and insulin sensitivity in hypertensive obese women

Role of gender in explaining metabolic syndrome risk factors in an Iranian rural population using structural equation modelling

Many factors can lead to an increase in the prevalence of metabolic syndrome (MetS) in different populations. Using an advanced structural equation model (SEM), this study is aimed to determine the most important risk factors of MetS, as a continuous latent variable, using a large number of males and females. We also aimed to evaluate the interrelations among the associated factors involved in the development of MetS. This study used data derived from the Fasa PERSIAN cohort study, a branch of the PERSIAN cohort study, for participants aged 35 to 70 years with 10,138 males and females. SEM was used to evaluate the direct and indirect effects, as well as gender effects of influencing factors. Results from the SEM showed that in females most changes in MetS are described by waist circumference (WC), followed by hypertension (HP) and triglyceride (TG), while in males most changes in MetS are described by WC, followed by TG then fasting blood glucose (FBG). Results from the SEM confirmed the gender effects of social status on MetS, mediated by sleep and controlled by age, BMI, ethnicity and physical activity. This study also shows that the integration of TG and WC within genders could be useful as a screening criterion for MetS in our study population.

Body composition assessment of people with overweight/obesity with a simplified magnetic resonance imaging method

To develop a simplified magnetic resonance imaging method (MRI) to assess total adipose tissue (AT) and adipose tissue free mass (ATFM) from three single MRI slices in people with overweight/obesity in order to implement body composition follow-up in a clinical research setting. Body composition of 310 participants (70 women and 240 men, age: 50.8 ± 10.6 years, BMI: 31.3 ± 5.6 kg.m^-2) was assessed with 3 single slices (T6-T7, L4-L5 and at mid-thigh) MRI. Multiple regression analysis was used to develop equations predicting AT and ATFM from these three single slices. Then we implemented a longitudinal phase consisting in a 2-month exercise training program during which we tested the sensitivity of these equations in a subgroup of participants with overweight/obesity (n = 79) by comparing the exercise-induced variations between predicted and measured AT and ATFM. The following equations: total AT = - 12.74105 + (0.02919 × age) + (4.27634 × sex (M = 0, F = 1)) + (0.22008 × weight) + (26.92234 × AT T6-T7) + (23.70142 × AT L4-L5) + (37.94739 × AT mid-thigh) and total ATFM = - 33.10721 + (- 0.02363 × age) + (- 3.58052 × sex (M = 0, F = 1)) + (30.02252 × height) + (0.08549 × weight) + (11.36859 × ATFM T6-T7) + (27.82244 × ATFM L4-L5) + (58.62648 × ATFM mid-thigh) showed an excellent prediction (adjusted R² = 97.2% and R² = 92.5%; CCC = 0.986 and 0.962, respectively). There was no significant difference between predicted and measured methods regarding the AT variations (- 0.07 ± 2.02 kg, p = 0.70) and the ATFM variations (0.16 ± 2.41 kg, p = 0.49) induced by 2-months of exercise training. This simplified method allows a fully accurate assessment of the body composition of people with obesity in less than 20 min (10 min for images acquisition and analysis, respectively), useful for a follow-up.

Adipose methylome integrative-omic analyses reveal genetic and dietary metabolic health drivers and insulin resistance classifiers

BACKGROUND

There is considerable evidence for the importance of the DNA methylome in metabolic health, for example, a robust methylation signature has been associated with body mass index (BMI). However, visceral fat (VF) mass accumulation is a greater risk factor for metabolic disease than BMI alone. In this study, we dissect the subcutaneous adipose tissue (SAT) methylome signature relevant to metabolic health by focusing on VF as the major risk factor of metabolic disease. We integrate results with genetic, blood methylation, SAT gene expression, blood metabolomic, dietary intake and metabolic phenotype data to assess and quantify genetic and environmental drivers of the identified signals, as well as their potential functional roles.

METHODS

Epigenome-wide association analyses were carried out to determine visceral fat mass-associated differentially methylated positions (VF-DMPs) in SAT samples from 538 TwinsUK participants. Validation and replication were performed in 333 individuals from 3 independent cohorts. To assess functional impacts of the VF-DMPs, the association between VF and gene expression was determined at the genes annotated to the VF-DMPs and an association analysis was carried out to determine whether methylation at the VF-DMPs is associated with gene expression. Further epigenetic analyses were carried out to compare methylation levels at the VF-DMPs as the response variables and a range of different metabolic health phenotypes including android:gynoid fat ratio (AGR), lipids, blood metabolomic profiles, insulin resistance, T2D and dietary intake variables. The results from all analyses were integrated to identify signals that exhibit altered SAT function and have strong relevance to metabolic health.

RESULTS

We identified 1181 CpG positions in 788 genes to be differentially methylated with VF (VF-DMPs) with significant enrichment in the insulin signalling pathway. Follow-up cross-omic analysis of VF-DMPs integrating genetics, gene expression, metabolomics, diet, and metabolic traits highlighted VF-DMPs located in 9 genes with strong relevance to metabolic disease mechanisms, with replication of signals in FASN, SREBF1, TAGLN2, PC and CFAP410. PC methylation showed evidence for mediating effects of diet on VF. FASN DNA methylation exhibited putative causal effects on VF that were also strongly associated with insulin resistance and methylation levels in FASN better classified insulin resistance (AUC=0.91) than BMI or VF alone.

CONCLUSIONS

Our findings help characterise the adiposity-associated methylation signature of SAT, with insights for metabolic disease risk.

No Changes in Body Composition in NCAA Division I Collegiate Football Players because of COVID-19 Restrictions

ABSTRACT

Czeck, MA, Roelofs, EJ, Evanoff, NG, and Dengel, DR. No Changes in body composition in NCAA Division I Collegiate Football Players due to COVID-19 restrictions. J Strength Cond Res 36(6): 1749-1752, 2022-The purpose of this study was to explore the impact of coronavirus disease 2019 (COVID-19) restrictions on body composition, assessed by dual x-ray absorptiometry (DXA), between the 2020 postseason (pre-COVID-19 restrictions) and the 2021 postseason (post-COVID-19 restrictions) in collegiate football players (n = 50). In addition, a subset of athletes (n = 23) was used to explore body composition variables across 4 postseason time points. Body composition variables assessed were total and regional body fat percent, total mass, lean mass, fat mass, bone mineral content, bone mineral density, and visceral adipose tissue mass. Paired t-tests were used to determine differences between the 2020 postseason and the 2021 postseason in body composition variables. Analysis of variance with Tukey HSD post hoc tests assessed significant differences in total and regional body composition across 4 years while adjusting for multiple comparisons. There were no significant differences (p > 0.05) between postseason 2020 and postseason 2021 for all measures of body composition. In a subset of athletes, body composition was analyzed over a 4-year period of time. There were no significant differences between all 4 time points for all measures of body composition. In conclusion, body composition variables in this study's subjects were not affected because of coronavirus disease 2019 restrictions or over 4 years of their collegiate football career.

Handgrip Strength-Related Factors in a Colombian Hypertensive Population: A Cross-Sectional Study

(1) Background: This study determined the factors associated with manual grip strength in people with high blood pressure (HBP); (2) Methods: 219 subjects participated in this cross-sectional study, which evaluated muscle strength (manual dynamometer), sociodemographic factors, clinical characteristics, level of physical activity (International Physical Activity Questionnaire-IPAQ score), and depression (Zung's Depression Self-Rating Scale); (3) Results: The bivariate analysis found that handgrip strength in people with HPB was associated with sex (p = 0.000), age (p = 0.000), ethnicity (p = 0.019), smoking habits (p = 0.037), alcohol consumption (p = 0.004), diastolic blood pressure (p = 0.012), weight (p = 0.000), height (p = 0.000), measurement of waist circumference (p = 0.002), depression (p = 0.041), and IPAQ score (p = 0.000). Regardless of being male or female, handgrip strength was associated with age (p = 0.009), IPAQ (p = 0.000), weight (p = 0.038), height (p = 0.000), DPB units (p = 0.043), and depression (p = 0.020). The multivariate generalized linear gamma regression model showed that the coefficient with the greatest weight, regardless of sex, was age (p = 0.043), level of physical activity (24% more at high level than at low level, p = 0.031), and depression (moderate/severe depression level) associated with lower handgrip strength (p = 0.025); (4) Conclusions: Handgrip strength showed an association with level of physical activity, age, and level of depression in a middle-aged population with HBP.

Association of abdominal muscle area and density with glucose regulation: The multi-ethnic study of atherosclerosis (MESA)

AIMS

Previous characterisation of body composition as a type 2 diabetes mellitus (T2DM) risk factor has largely focused on adiposity, but less is known about the independent role of skeletal muscle. We examined associations between abdominal muscle and measures of glucose regulation.

MATERIALS AND METHODS

Cross-sectional analysis of 1,891 adults enrolled in the Multi-Ethnic Study of Atherosclerosis. Multivariable regression assessed associations between abdominal muscle area and density (measured by computed tomography) with fasting glucose, homeostasis model assessment of insulin resistance (HOMA-IR), and prevalent T2DM (fasting glucose ≥126 mg/dL or medication use).

RESULTS

In minimally adjusted models (age, sex, race/ethnicity, income), a 1-SD increment in abdominal muscle area was associated with higher HOMA-IR (β = 0.20 ± SE 0.03; 95%CI: 0.15, 0.25; P < 0.01) and odds of T2DM (OR = 1.47; 95%CI: 1.18, 1.84; P < 0.01), while higher density was associated with lower fasting glucose (-4.49 ± 0.90; -6.26, -2.72; P < 0.01), HOMA-IR (-0.16 ± 0.02; -0.20, -0.12; P < 0.01), and odds of T2DM (0.64; 0.52, 0.77; P < 0.01). All associations persisted after adjustment for comorbidities and health behaviours. However, after controlling for height, BMI, and visceral adiposity, increasing muscle area became negatively associated with fasting glucose (-2.23 ± 1.01; -4.22, -0.24; P = 0.03), while density became positively associated with HOMA-IR (0.09 ± 0.02; 0.05, 0.13; P < 0.01).

CONCLUSIONS

Increasing muscle density was associated with salutary markers of glucose regulation, but associations inverted with further adjustment for body size and visceral adiposity. Conversely, after full adjustment, increasing muscle area was associated with lower fasting glucose, suggesting some patients may benefit from muscle-building interventions.

Association of adiposity evaluated by anthropometric, BIA, and DXA measures with cardiometabolic risk factors in nonobese postmenopausal women: the CoLaus/OsteoLaus cohort

OBJECTIVE

After menopause, body composition changes with body fat accumulation, and an increase in cardiometabolic risk factors. Total fat mass, regional fat mass, and visceral adipose tissue (VAT) may be estimated with anthropometric measures, bioelectrical impedance analysis (BIA), and dual-energy X-ray absorptiometry (DXA). The aim of our study was to assess which measurement correlated best with cardiometabolic risk factors in healthy nonobese postmenopausal women.

METHODS

The CoLaus/OsteoLaus cohort included 1,500 postmenopausal women (age range 50-80). We analyzed correlations between: 1) measurements of body composition assessed by anthropometric measures, BIA, and DXA and 2) these measurements and different selected cardiometabolic risk factors, such as blood pressure, lipid markers (cholesterol subtypes and triglycerides), and metabolic markers (glucose, insulin, adiponectin, and leptin). Spearman correlation coefficient, stepwise forward regression, and linear regression analyses were used to determine association between anthropometric measurements and cardiometabolic risk factors.

RESULTS

In the 803 included participants (mean age 62.0 ± 7.1 y, mean body mass index 25.6 kg/m2 ± 4.4), correlations between total fat mass measured by BIA and total fat mass, android fat, gynoid fat, or VAT measured by DXA are very strong (from r = 0.531, [99% confidence interval (CI), 0.443-0.610] to r = 0.704, [99% CI, 0.640-0.758]). Body mass index and waist circumference have a higher correlation with VAT (r = 0.815, [99% CI, 0.772-0.851] and r = 0.823 [99% CI, 0.782-0.858], respectively) than BIA (r = 0.672 [99% CI, 0.603-0.731]). Among the anthropometric measurement and the measurements derived from DXA and BIA, VAT is the parameter most strongly associated with cardiometabolic risk factors. VAT better explains the variation of most of the cardiometabolic risk factors than age and treatment. For example, nearly 5% of the variability of the diastolic blood pressure (9.9 vs 4.9), nearly 15% of the variability of high-density lipoprotein cholesterol (20.3 vs 3.8) and triglyceride (21.1 vs 6.5), 25.3% of the variability of insulin (33.3 vs 8.1), and 37.5% of the variability of leptin (37.7 vs 1.1) were explained by VAT.

CONCLUSIONS

BIA seems not to be a good tool to assess VAT. At the population level, waist circumference and body mass index seem to be good tools to estimate VAT. VAT measured by DXA is the parameter most correlated with cardiometabolic risk factors and could become a component of the cardiometabolic marker on its own.

Effect of resistance training with and without caloric restriction on visceral fat: A systemic review and meta-analysis

We performed a systematic review and meta-analysis to investigate the effect of resistance training (RT) with and without caloric restriction (CR) on visceral fat (VF). PubMed and Scopus were searched to identify original articles published through December 2020. Standardized mean differences and 95% confidence intervals (95% CIs) were determined, and separate analyses were conducted for RT versus control, and RT plus CR versus CR only. Thirty-four studies including 38 intervention arms and involving 2285 were included in the meta-analysis. RT effectively reduced VF [-24 (95% CI -0.34 to -0.13), p < 0.001; I²  = 4.17%, p = 0.40; 24 intervention arms] when compared with control. Based on subgroup analyses, reduction in VF was significant for individual with (p = 0.04) and without (p < 0.001) obesity as well as across medium-term (p = 0.001) and long-term (p = 0.002) interventions. Reduction in VF was significant for both middle-age (p = 0.03) and elderly (p = 0.001) adults but was not significant for pediatric (p = 0.08) participants. However, RT plus CR did not indicate superiority effect on VF [0.23 95% CI -0.04 to 0.51, p = 0.09; I²  = 58.76%, p = 0.003; 14 intervention arms] when compared with CR only. Our results confirm that RT may be effective for reducing VF, but adding RT with CR was not associated with a greater effect for reducing VF.

The relation between submaximal aerobic exercise improving vascular elasticity through loss of visceral fat and antihypertensive

Purpose: We sought to observe the effect of submaximal aerobic exercise on abdominal obesity in hypertension patients and to clarify a correlation between blood pressure improvement and visceral fat, along with arterial elasticity. Materials and Methods: According to the treatment plan, the patients were divided into two groups: the combined treatment group and the single drug group. During the training period, the subjects in the combined treatment group performed a 60 min treadmill exercise at 65% of Pmax. PWV was measured using blood pressure pulse-wave detectors before and after treatment. We assessed carotid stiffness and visceral fat area by B‑mode ultrasonography. Results: The 24-h SBP and DBP changed significantly in the two groups in the pre- and post-treatment comparison. Significant statistical differences among SBP and DBP in the two groups of combination therapy and drug therapy after 12 months were demonstrated. Visceral fat area was significantly reduced in the combination therapy group compared to the drug therapy group at the last assessment. Compared with the drug group, arterial compliance in the combination therapy group was higher after treatment. Blood pressure showed significant positive correlation with visceral fat area, PWV, β‑stiffness, Ep, and PWVβ in the combination therapy group. Conclusion: The combination of drug therapy and is more effective than just pursuing single drug treatment of hypertension in patients with abdominal obesity. Submaximal aerobic exercise contributes to anti-hypertension. The main mechanism of anti-hypertension in combination with drug therapy and submaximal aerobic exercise is the improvement of vascular elasticity and decreased central body-fat distribution.

Socio-demographic factors and health status of adults with disability in Enugu Metropolis, Nigeria

Background

Disability is a major determinant of impaired health and nutritional status. This study aims to assess the health and nutritional status of adults with disability and their relationship with socio-demographic factors.

Methods

A descriptive cross-sectional study of 323 adults with disability in support-centers/schools of disability in Enugu Metropolis, Nigeria was conducted. The participants' socio-demographic factors, behavioural characteristics and 24-hour dietary recall were recorded. Blood pressure and anthropometric measurements of height, weight, waist and hip circumference were obtained. The height and weight measurements of non-ambulatory participants were estimated from knee height and mid-arm circumference. Biochemical analyses of blood samples were also performed. Multiple logistic regression was used to assess the effect of socio-demographic factors on health and nutritional status.

Results

The participants consisted of females (59.3%) within the age of 20 to 30 years (59.1%). The major area of difficulty was in physical mobility (51.1%) and this occurred mostly in females (26.9%). The participants' mean daily intakes of calorie, protein and fat were below the recommended dietary allowances. The participants were overweight (49.2%), obese (4.6%), hypertensive (29.7%) and diabetic (12.1%). Dyslipidemia (81.8%), anemia (63.6%) and zinc deficiency (51.1%) were highly prevalent among the study group. Gender difference was observed in alcohol consumption (p=0.000), smoking habit (p=0.001), waist circumference (WC)(p=0.000), waist-hip-ratio (WHR) (p=0.000), triglyceride (p=0.026) and haemoglobin concentration (p=0.007). Being boarder was a positive predictor of overweight/obesity (OR= 2.974, 95% CI=1.449-6.104), abnormal WHR (OR=2.893, 95% CI = 1.073-7.801) and hypertension (OR=8.381, 95% CI=1.598-13.959). Female gender was associated with abnormal WC (OR=7.219, 95% CI=3.116-14.228) and WHR (OR=3.590, 95% CI=2.095-6.150) whereas older age-group was associated with overweight/obesity (OR=1.908, 95% CI=1.137- 3.202). Being employed was a negative predictor of hypertension.

Conclusion

Overweight/obesity, anemia, zinc deficiency and dyslipidemia were highly prevalent among persons living with disability in Enugu Metropolis.

Role of body visceral fat in hypertension and dyslipidemia among the diabetic and nondiabetic ethnic population of Tripura-A comparative study

BACKGROUND

Excess fat in the upper part of human body correlates with increased mortality and risk for diabetes, dyslipidemia, and hypertension. In India, there are very limited data available on the association of excess body visceral fat with hypertension and dyslipidemia independent of obesity and diabetes.

OBJECTIVE

The objective of this study is to assess the role of body visceral fat percentage in hypertension and dyslipidemia among diabetic and nondiabetic indigenous ethnic population of Tripura.

METHODS

Random blood sugar test was done for each of the study subjects with the help of a standard and validated glucometer. Then, blood samples were obtained after an 8-12-h overnight fast using vacutainer. Later on, all the blood samples were transported to the MRU laboratory at Agartala Government Medical College maintaining cold chain for following investigations: (1) FBS, PP by GOD-POD method; (2) HbA1c by immunoturbidimetric method; (3) cholesterol estimation by CHOD-PAP method; and (4) triglyceride estimation by glycerol phosphate oxidase method.

RESULTS

In this study, it has been found that 62.5% diabetic subjects having high body visceral fat are suffering from Dyslipidemia, whereas only 42.9% nondiabetic subjects with high body visceral fat percentage are having dyslipidemia. Fisher's exact test showed association between diabetes status and body visceral fat (P = 0.048). It has been also observed that there was significant (P < 0.05) association between hypertension and body visceral fat among local indigenous ethnic population of Tripura.

CONCLUSION

Body visceral fat percentage is significantly associated with hypertension, dyslipidemia, and type-2 diabetes among indigenous ethnic population of Tripura.

Body Composition and Bone Mineral Density of Division 1 Collegiate Track and Field Athletes, a Consortium of College Athlete Research (C-CAR) Study

The purpose of the present study was to generate normative values for total and regional body composition in male and female Division 1 collegiate track and field athletes using dual X-ray absorptiometry. We also sought to examine body composition by event and sex. Data were used from the Consortium of College Athlete Research group. A total of 590 (male [M]/female [F] = 274/316) athletes had their height, weight, total and regional fat mass (FM), lean mass, and bone mineral density (BMD) measured. Athletes were classified into 1 of 7 categories: Jumps (M/F = 28/30); Long Distance (M/F = 104/110), Middle Distance (M/F = 27/24), Multievent (M/F = 11/9), Pole Vault (M/F = 21/27), Sprints (M/F = 54/96), and Throws (M/F = 29/20). Total and regional differences between events and sex were assessed by analysis of variance. Except for male and female throwers, all other track and field athletes' mean percent body fat (M: 10.3%-12.6%, F: 17.5%-21.6%) and visceral FM (<500 g) was low, but in a healthy range. As expected, throwers had significantly (p < 0.05) higher total and regional FM and lean mass than other events. In addition, male (1.55 ± 0.11 g/cm²) and female (1.40 ± 0.12 g/cm²) throwers had significantly greater BMD than all other events while male (1.25 ± 0.10 g/cm²) and female (1.16 ± 0.09 g/cm²) distance runners had significantly lower BMD than all other events. In conclusion, track athletes' body composition differed across events for both males and females. These measurements provide normative data on NCAA Division 1 male and female track and field athletes.

Comparing the ability of anthropometric indicators in determining the prevalence of hypertension among Indian tribes

OBJECTIVE

We compared the ability of the selected anthropometric indicators to best predict the prevalence of hypertension among the Indian tribes.

METHODS

A cross-sectional study was undertaken among 1431 adult participants (705 males and 726 females) between the ages of 20 and 60 years from six major tribes in India. Selected anthropometric indicators such as body mass index (BMI), waist-hip-ratio (WHR), waist-height-ratio (WHtR), percentage body fat (PBF), visceral fat (VF), minimum-waist-circumference (MWC) and sum-of-the-four skinfold thickness (SF4), along with the physiological parameters such as blood pressure were recorded. Discriminant analysis (DA) was performed to examine and compare the ability of the selected anthropometric indicators towards classifying hypertension among males, females and the total population.

RESULTS

Significant independent association was observed for hypertension and similar conditions within gender and selected age-group categories. The overall hypertension prevalence among the studied tribes was observed at 12.6%. Standardized function coefficients (SFCs) in discriminant analysis revealed PBF(0.89, 0.36, and 0.76 for overall, males, and females respectively) as the most powerful discriminator of hypertension. In addition, visceral fat (0.74, 1.46, and 0.58 for overall, males and females respectively) was observed to be the other significant indicator of hypertensive blood pressure. These exploratory findings for the first time indicate fat deposition, rather than body density alone, as an emerging physiological and metabolic risk among Indian tribes.

CONCLUSION

In the context of the highly prevalent chronic undernutrition, internal fat deposition is a major classifying factor of physiological and metabolic intolerance. It also indicates the increasing trend in lifestyle changes and the associated adversities among the Indian tribes.

Cardiovascular risk factors: Is the metabolic syndrome related to aging? Epidemiology in a Portuguese population

AIMS

The primary objective of our study is to determine the prevalence of the metabolic syndrome in the population. The secondary objective is to determine the prevalence of cardiovascular risk factors, anthropometric alterations and the prevalence of target organ damage and their relationship with aging.

MATERIAL AND METHODS

The sample for the study was obtained by means of a consecutive population-based demonstration in 803 adults over 18 years of age belonging to the labor force of the company Grupo Delta SA. The study was carried out according to the guidelines of the Declaration of Helsinki. The individuals included in the study voluntarily participated, once informed of the purpose of the study, giving their prior verbal consent, to the company's human resources department, in the case of Delta Group workers.

RESULTS

23.8% of the population has metabolic syndrome more prevalent in males, no smoking, no significant alcohol consumption, sedentary, with a high Body mass index (BMI). Its prevalence increases with age.

CONCLUSION

We found that the prevalence of metabolic syndrome increases with age and is present in people of working age, increasing the risk of cardiovascular diseases, work-related absences, and socio-economic costs.

Potential application of testosterone replacement therapy as treatment for obesity and type 2 diabetes in men

Sedentary lifestyle and over-nutrition are the main causes of obesity and type 2 diabetes (T2D). However, the same causes are major triggers of hypogonadism. Many T2D patients show low testosterone levels while hypogonadal men seem to be prone to become diabetic. Testosterone plays a major role in the regulation of muscle mass, adipose tissue, inflammation and insulin sensitivity and is therefore indirectly regulating several metabolic pathways, while T2D is commonly triggered by insulin resistance, increased adipose tissue and inflammation, showing a negative correlation between testosterone levels and T2D. Testosterone replacement therapy (TRT) is widely used in patients with symptoms of hypogonadism, however it is not commonly used as preventive intervention or treatment for T2D patients even though hypogonadal patients share many common symptoms (obesity, insulin insensitivity, increased inflammation, decrease in muscle mass and strength) with T2D patients. Even though TRT is often associated with side effects such as prostatic hypertrophy or cancer, cardiovascular risks due to increase in the number of red blood cells and infertility, several studies have shown that TRT remains a potent intervention improving metabolic functions such as glycated haemoglobin, blood sugar, total cholesterol and visceral fat. The purpose of this review is to discuss the possible benefits and risks of TRT in the prevention and treatment of obesity and T2D and assess the health risks and benefits of common T2D medications and testosterone.

Derivation and validation of a new visceral adiposity index for predicting visceral obesity and cardiometabolic risk in a Korean population

Objectives

The visceral adiposity index (VAI), an indirect marker of visceral adipose tissue, serves as a model associated with cardiometabolic risk, but has limitations regarding the Asian population. We sought to develop a new VAI (NVAI) for the Korean population and compare it to VAI for prediction of atherosclerotic cardiovascular disease (ASCVD) risk and development of major cardiovascular diseases (CVD) and stroke.

Methods

Patients (969) who underwent visceral fat area measurement were analyzed. After exclusion, 539 patients (142 men, 397 women) were randomly divided into internal (n = 374) and external validation (n = 165) data set. The NVAI was developed using univariate and multivariate logistic regression with backward selection of predictors. Receiver operating characteristic (ROC) curve analysis and comparison of the area under the curve (AUC) verified the better predictor of ASCVD risk score. Additionally, nationwide population-based cross-sectional survey data (Korean National Health and Nutrition Examination Survey [KNHANES] 2008–2010, n = 29,235) was used to validate the NVAI’s ability to predict ASCVD risk and major CVD and stroke.

Results

The NVAI better reflected visceral fat area in internal and external data sets, with AUCs of 0.911 (95% confidence interval [CI]: 0.882–0.940) and 0.879 (95% CI: 0.828–0.931), respectively. NVAI better discriminated for ASCVD risk (AUC = 0.892, 95% CI: 0.846–0.938) compared to VAI (0.559, 95% CI: 0.439–0.679). The NVAI also better predicted MI or angina, and stroke with AUCs of 0.771 (95% CI: 0.752–0.789), and 0.812 (95% CI: 0.794–0.830), respectively, compared with waist circumference (WC), body mass index (BMI), TG to HDL ratio, and VAI via KNHANES, in a statistically significant manner.

Conclusions

The NVAI has advantages as a predictor of visceral obesity and is significantly associated with ASCVD risks and development of major CVD and stroke in the Korean population. The NVAI could be a screening tool for improved risk estimation related to visceral obesity.

Association of subcutaneous and visceral fat with circulating microRNAs in a middle-aged Japanese population

Purpose It has been demonstrated that circulating microRNA profiles are affected by physiological conditions. Several studies have demonstrated that microRNAs play important roles in the regulation of adiposity. However, few have investigated the relationship between circulating microRNAs and obesity, which has become a major public health problem worldwide. This study investigated the association between circulating microRNAs and obesity in a Japanese population. Methods Obesity parameters, such as subcutaneous and visceral fat adipose tissue, body fat percentage, and body mass index were assessed in a cross-sectional sample of 526 participants who attended health examinations in Yakumo, Japan. In addition, five circulating microRNAs (miR-20a, -21, -27a, -103a, and -320), which are involved in adipocyte proliferation and differentiation, were quantified using real-time polymerase chain reaction amplification. Results We compared the circulating microRNA concentrations in a percentile greater than 75th (high) with below the value (low) of subcutaneous adipose tissue, visceral fat adipose tissue, body mass index, and per cent body fat. For visceral fat adipose tissue, significant decrease in miR-320 expression was observed in high group. Also, for body mass index, significant change of miR-20a, -27a, 103a, and 320 expression level was observed in high group. Multiple linear regression analysis demonstrated that circulating levels of some microRNA such as miR-27a were significantly associated with subcutaneous adipose tissue, visceral fat adipose tissue, and body mass index. Conclusions Our findings support the need for further studies to determine whether such changes are consistent across different populations and whether the identified microRNAs may represent novel biomarkers to predict the susceptibility and progression of obesity-related disorders.

MicroRNAs in dysfunctional adipose tissue: cardiovascular implications

In this review, we focus on the emerging role of microRNAs, non-coding RNAs that regulate gene expression and signaling pathways, in dysfunctional adipose tissue. We highlight current paradigms of microRNAs involved in adipose differentiation and function in depots such as white, brown, and beige adipose tissues and potential implications of microRNA dysregulation in human disease such as obesity, inflammation, microvasculature dysfunction, and related cardiovascular diseases. We highlight accumulating studies indicating that adipocyte-derived microRNAs may not only serve as biomarkers of cardiometabolic disease, but also may directly regulate gene expression of other tissues. Finally, we discuss the future prospects, challenges, and emerging strategies for microRNA delivery and targeting for therapeutic applications in cardiovascular disease states associated with adipocyte dysfunction.

Sexual dimorphism in the glucose homeostasis phenotype of the Aromatase Knockout (ArKO) mice

We investigated the effects of estrogens on glucose homeostasis using the Aromatase Knockout (ArKO) mouse, which is unable to convert androgens into estrogens. The ArKO mouse is a model of total estrogen ablation which develops symptoms of metabolic syndrome. To determine the development and progression of whole body state of insulin resistance of ArKO mice, comprehensive whole body tolerance tests were performed on WT, ArKO and estrogen administrated mice at 3 and 12 months of age. The absence of estrogens in the male ArKO mice leads to hepatic insulin resistance, glucose and pyruvate intolerance from 3 to 12 months with consistent improvement upon estrogen treatment. Estrogen absence in the female ArKO mice leads to glucose intolerance without pyruvate intolerance or insulin resistance. The replacement of estrogens in the female WT and ArKO mice exhibited both insulin sensitizing and resistance effects depending on age and dosage. In conclusion, this study presents information on the sexually dimorphic roles of estrogens on glucose homeostasis regulation.

Association between individual fat depots and cardio-metabolic traits in normal- and overweight children, adolescents and adults

OBJECTIVES

To determine age-related associations between fat mass (FM), regional fat depots and cardiometabolic traits in normal- and overweight children, adolescents and adults.

METHODS

Detailed body composition (regional subcutaneous and visceral adipose tissue; SAT, VAT) by whole-body magnetic resonance imaging (MRI), FM and fat-free mass by air-displacement plethysmography, systolic and diastolic blood pressure (SBP, DBP), triglycerides (TG), high-density lipoprotein cholesterol (HDL), plasma glucose and plasma insulin were measured in 433 subjects (BMI: 23.6 (21.0-27.7); 151 children and adolescents, aged 6-18 years, 150 young adults, aged 18-30 years and 132 adults, aged 30-60 years). Data were derived from pooled data of the 'Reference Center for Body Composition' in Kiel, Germany. Insulin resistance was determined by the homeostatic model assessment of insulin resistance (HOMA-IR). Partial correlations and multivariate linear regression analyses were used to evaluate the associations between body composition and cardiometabolic traits. A descriptive approach was used to demonstrate age-dependent differences in associations between body fat depots and insulin resistance, independent of BMI.

RESULTS

FM, SAT, and VAT increased from childhood to adulthood with low VAT in children and adolescents. When compared to children, TG was higher in adults. HDL and DBP did not differ between age groups. Insulin resistance was highest in male adolescents and female young adults. Associations between body fat depots and cardiometabolic traits were seen after puberty with no associations in pre- and intrapubertal children. When compared to FM, SAT and VAT had the strongest association with insulin resistance in adults. This association was independent of BMI.

CONCLUSIONS

Associations between individual body fat depots and most cardiometabolic traits became evident after puberty only. The strongest associations were observed between insulin resistance and abdominal fat in adults. The impact of VAT was independent of BMI.

Obesity-Induced Hypertension Develops in Young Rats Independently of the Renin-Angiotensin-Aldosterone System

A correlation exists between obesity and hypertension. In the currently available models of diet-induced obesity, the treatment of rats with a high fat (HF) diet does not begin until adulthood. Our aim was to develop and characterize a model of pre-pubescent obesity-induced hypertension. Male Sprague-Dawley rats were fed a HF diet (35% fat) for 10 weeks, beginning at age 3 weeks. Blood pressure was measured by tail-cuff, and a terminal blood sample was obtained to measure fasting blood glucose, insulin, plasma renin, aldosterone, thiobarbitutic acid reactive substances (TBARS), and free 8-isoprostanes levels. The vascular reactivity in the aorta was assessed using a myograph. Blood pressure was increased in rats fed the HF diet (HF, 161 ± 2 mm Hg vs. control, 137 ± 2 mm Hg, P < 0.05). Blood glucose (HF, 155 ± 4 mg/dL vs. control, 123 ± 5 mg/dL, P < 0.05), insulin (HF, 232 ± 63 pM vs. control, 60 ± 11 pM, P < 0.05), TBARS (expressed as nM of malondialdehyde [MDA]/ml [HF, 1.8 ± 0.37 nM MDA/ml vs. control 1.05 ± 0.09 nM MDA/ml, P < 0.05]), and free 8-isoprostanes (HF, 229 ± 68 pg/ml vs. control, 112 ± 9 pg/ml, P < 0.05) levels were elevated in the HF diet group. Interestingly, plasma renin and aldosterone levels were not different between the groups. The maximum vasoconstriction to phenylephrine (10−4 M) was increased in the HF diet group (HF, 26.1 ± 1.5 mN vs. control 22.3 ± 1.2 mN, P < 0.05). In conclusion, pre-pubescent rats become hypertensive and have increased oxidative stress and enhanced vasoconstriction when fed a HF diet. Surprisingly, this occurs without the increase in renin or aldosterone levels seen in the adult models of diet-induced obesity.

Blockade of the renin-angiotensin system in small arteries and anticontractile function of perivascular adipose tissue

BACKGROUND/AIMS

In patients with obesity, there is increased inflammation with attendant oxidative stress in perivascular adipose tissue. This has functional consequences with loss of vasodilator adipokine bioavailability. Part of the inflammatory response is mediated by increased activation of the renin-angiotensin-aldosterone axis. Therefore, this study was designed to investigate whether angiotensin-converting enzyme inhibitors or angiotensin receptor blockers can improve the anticontractile function of perivascular adipose tissue.

METHODS

Segments of rat mesenteric small artery were dissected and mounted in a wire myograph and contracted to incremental doses of norepinephrine in the presence and absence of perivascular adipose tissue and in conditions of normal oxygenation or after hypoxia and incubated with captopril or telmisartan.

RESULTS

Vessels with perivascular adipose tissue contracted significantly less than arteries with perivascular adipose tissue removed under normal oxygenation conditions, indicating that perivascular adipose tissue exerts an anticontractile effect. Hypoxia induced a loss of this anticontractile effect which could be completely prevented with captopril or telmisartan.

CONCLUSION

The in-vitro creation of a hypoxic environment can simulate the loss of anticontractile perivascular adipose tissue function seen in vivo in obese patients, and this can be prevented using inhibitors of the renin-angiotensin cascade.

Impact of gentamicin coadministration along with high fructose feeding on progression of renal failure and metabolic syndrome in Sprague-Dawley rats

The current study evaluates the impact of high fructose feeding in rat model of gentamicin induced nephrotoxicity. Sprague-Dawley rats weighing 180–200 g were randomized into four groups; (C) received standard rodents chow with free access to ad libitum drinking water for 8 weeks and was considered as control, (F) received standard rodents chow with free access to drinking water supplemented with 20% (W/V) fructose for the same abovementioned period, (FG) was fed as group F and was given 80 mg/kg (body weight)/day gentamicin sulphate intraperitoneally during the last 20 days of the feeding period, and (G) was given gentamicin as above and fed as group C. Renal function was assessed at the end of the treatment period through measuring serum creatinine, uric acid and albumin, creatinine clearance, absolute and fractional excretion of both sodium and potassium, twenty-four-hour urinary excretion of albumin, and renal histology. For metabolic syndrome assessment, fasting plasma glucose and insulin were measured and oral glucose tolerance test was performed throughout the treatment period. Results showed that gentamicin enhances progression of fructose induced metabolic syndrome. On the other hand, fructose pretreatment before gentamicin injection produced a comparable degree of renal dysfunction to those which were given fructose-free water but the picture of nephrotoxicity was somewhat altered as it was characterized by higher extent of glomerular congestion and protein urea. Overall, more vigilance is required when nephrotoxic drugs are prescribed for patients with fructose induced metabolic syndrome.

Leptin increases blood pressure and markers of endothelial activation during pregnancy in rats

Raised leptin levels have been reported in the placentae and serum of women with elevated blood pressure and proteinuria during pregnancy. The role of leptin in this however remains unknown. This study investigates the effect of leptin administration on systolic blood pressure (SBP) and proteinuria and serum markers of endothelial activation during pregnancy in Sprague Dawley rats. From day 1 of pregnancy, 24 rats were randomised into those given either saline (group 1) or leptin at 60 or 120 μ g/kg/body weight/day (groups 2 and 3 resp.). SBP was measured every 5 days and 24-h urinary protein was measured at days 0 and 20 of pregnancy. Animals were euthanised on day 20 of pregnancy, and serum was collected for estimation of E-selectin and ICAM-1. Compared to group 1, SBP during the latter part of the pregnancy was significantly higher in the leptin-treated group (P < 0.01). Urinary protein excretion, serum E-selectin, and ICAM-1 were significantly higher in leptin-treated rats (P < 0.05). It seems that leptin administration to normotensive Sprague Dawley rats during pregnancy significantly increases SBP, urinary protein excretion, and markers of endothelial activation. However, further studies are required to examine the underlying mechanism responsible for this and its relevance to preeclampsia in humans.

Effect of high saturated free fatty acids feeding on progression of renal failure in rat model of experimental nephrotoxicity

The current study evaluates the impact of high saturated fat feeding in rat model of experimental nephrotoxicity induced by gentamicin. Sprague-Dawley rats weighing 200 g were randomized into four groups; the first one received the standard rodents chow for 8 weeks and was treated as control, the second group (HFD)received an experimental high fat diet rich in palm kernel oil (40% of Calories as fat) for the same period. The third group (HFDG) was given 80 mg/kg (body weight)/day gentamicin sulphate intraperitoneally during the last 24 days of the feeding period while the fourth group was given gentamicin as above along with the standard rodents chow. Renal function was assessed through measuring serum creatinine, creatinine clearance and absolute and fractional excretion of both sodium and potassium. At the end, rats underwent a surgical procedure for blood pressure measurement. Renal function study showed a stronger nephrotoxicity for HFDG group. Hypertension was observed in HFD group while the pressure declined after gentamicin co-administration. Overall, changing the feeding behavior toward using more SAFFAs for rats injected with gentamicin promotes the progression of renal failure.

Comparação de métodos de avaliação da gordura corporal total e sua distribuição

OBJETIVO: Comparar dois métodos de avaliação da gordura corporal total e sua distribuição. MÉTODOS: Estudo transversal, aninhado a uma coorte. Em amostra de 62 mulheres realizou-se avaliação do estado nutricional, incluindo a gordura corporal (GC) total obtida pelo somatório de dobras cutâneas (ΣDC) e bioimpedância (BIA). Mensurou-se a distribuição da gordura visceral por ultrassonografia (USG) (espessura de gordura intra-abdominal-EIA) e circunferência da cintura (CC). Foram calculados o coeficiente de correlação de concordância (CCC) e o coeficiente de determinação (r²). RESULTADOS: A média de idade das pacientes foi de 48,19 (8,99) anos. Observou-se 36 (58,06%) mulheres com a CC muito aumentada e 42 (67,74%) com GC aumentada. Identificou-se moderada concordância (r² = 0,42; CCC = 0,59; p < 0,01), entre os métodos avaliados para determinação da gordura corporal (%) e uma ótima concordância (r² = 0,90; CCC = 0,91; p < 0,01) para a gordura corporal (kg), avaliadas por BIA e ΣDC. A comparação entre a CC e EIA (USG) evidenciou uma moderada concordância (r² = 0,49; p < 0,01), entre os métodos. CONCLUSÕES: Evidenciou-se moderada concordância na avaliação da gordura corporal total (%) e ótima concordância na avaliação da gordura corporal (kg), entre os métodos utilizados. Identificou-se uma moderada concordância entre os métodos de distribuição da gordura corporal.

Body Mass Index Misclassification of Obesity among Community Police Officers

Occupational health nurses are at the forefront of obesity assessment and intervention and must be aware of potential inaccuracies of obesity measurement. The purpose of this study was to identify the prevalence of obesity among a sample of 84 male police officers 22 to 63 years old and determine the accuracy of body mass index (BMI) in estimating obesity compared to body fat percent (BF %). BMI identified 39.3% of the participants as obese, compared to 70.2% by BF %. BMI misclassified normal-weight officers as obese or overweight and obese officers as normal 48.8% ( n = 41) of the time. The two misclassified groups had similar average BMIs but significantly different BF %. BMI was not an accurate measure of obesity among adult males. BMI underestimated the true prevalence of obesity and could represent a missed opportunity for early intervention and disease prevention.

Body mass index misclassification of obesity among community police officers

Occupational health nurses are at the forefront of obesity assessment and intervention and must be aware of potential inaccuracies of obesity measurement. The purpose of this study was to identify the prevalence of obesity among a sample of 84 male police officers 22 to 63 years old and determine the accuracy of body mass index (BMI) in estimating obesity compared to body fat percent (BF %). BMI identified 39.3% of the participants as obese, compared to 70.2% by BF %. BMI misclassified normal-weight officers as obese or overweight and obese officers as normal 48.8% (n = 41) of the time. The two misclassified groups had similar average BMIs but significantly different BF %. BMI was not an accurate measure of obesity among adult males. BMI underestimated the true prevalence of obesity and could represent a missed opportunity for early intervention and disease prevention.

Self-reported experiences of discrimination and visceral fat in middle-aged African-American and Caucasian women

The authors examined the association between self-reported experiences of discrimination and subtypes of abdominal fat (visceral, subcutaneous) in a population-based cohort of African-American and Caucasian women. Prior studies examining associations between discrimination and abdominal fat have yielded mixed results. A major limitation of this research has been the reliance on waist circumference, which may be a poor marker of visceral fat, particularly for African-American women. Participants were 402 (45% African-American, 55% Caucasian) middle-aged women from the Chicago, Illinois, site of the Study of Women's Health Across the Nation. Visceral and subcutaneous fat were assessed via computed tomography scans between 2002 and 2005. Linear regression models were conducted to test associations among discrimination and visceral and subcutaneous fat. After adjustment for age and race, every one-point increase on the discrimination scale was associated with a 13.03-cm(2) higher amount of visceral fat (P = 0.04). This association remained significant after further adjustments for total body fat and relevant risk factors, including depressive symptoms. Discrimination was not associated with subcutaneous fat in minimally (P = 0.95) or fully adjusted models. Associations did not differ by race. Findings suggest that visceral fat may be one potential pathway through which experiences of discrimination increase cardiovascular risk.

Generalised and abdominal adiposity are important risk factors for chronic disease in older people: results from a nationally representative survey

OBJECTIVES

To look at the trends in prevalence of generalised (body mass index (BMI) ≥ 25 kg/m2) and abdominal obesity (waist circumference (WC) >102 cm, men; > 88 cm, women) among older people from 1993 to 2008, prevalence of chronic disease by overweight/obesity and WC categories in England 2005 and evaluate the association of these measures with chronic diseases.

DESIGN

Analyses of nationally representative cross-sectional population surveys, the Health Survey for England (HSE).

PARTICIPANTS

Non-institutionalised men and women aged ≥ 65 years (in HSE 2005, 1512 men and 1747 women).

MEASUREMENTS

Height, weight, waist circumference, blood pressure measurements were taken according to standardised HSE protocols. Information collected on socio-demographic, health behaviour and doctor diagnosed health conditions.

RESULTS

Generalised obesity and abdominal obesity increased among men and women from 1993 to 2008. In 2005, the HSE 2005 focussed on older people. 72% of men and 68% of women aged over 65 were either overweight or obese. Prevalence of raised WC was higher in women (58%) than in men (46%). The prevalence of diabetes and arthritis was higher in people with generalised obesity in both sexes. Men were more likely to have had a joint replacement and had a higher prevalence of stroke if they were overweight only but women were more likely to have had a joint replacement only if they were obese (13%) and had a higher risk of falls with generalised obesity. The pattern was similar for the prevalence of chronic diseases by raised WC. Multivariate analysis showed that generalised and abdominal obesity was independently associated with risk of hypertension, diabetes and arthritis in both men and women. In women only, there was an association between generalised obesity and having a fall in the last year (OR: 1.5), and between abdominal obesity and having a joint replacement (OR: 1.9, p=0.01).

CONCLUSION

Complications of obesity such as diabetes, hypertension and arthritis, are more common in men and women aged over 65 who are overweight or obese, as well as in those with a raised WC. These conditions impact on morbidity, mortality and have cost implications for the health service and are known to improve with weight loss even in old age. Treatment strategies to address these conditions such as weight management and prevention of overweight and obesity are important even in older people. There is a need to ensure that older people are given appropriate advice about keeping physically active and eating sensibly.

Non-dipping pattern relates to endothelial dysfunction in patients with uncontrolled resistant hypertension

Resistant hypertension (RHTN) includes both patients whose blood pressure (BP) is uncontrolled on three or more medications (uncontrolled RHTN (UCRH)) and patients whose BP is controlled with use of four or more drugs (controlled RHTN (CRH)). It is unknown whether endothelial function and nocturnal drop demonstrate a similar pattern in patients with CRH and UCRH. We examined circadian BP patterns and vascular function in these patients. In all, 40 CRH and 26 UCRH patients, and 25 normotensives underwent biochemical testing, ambulatory BP monitoring, determination of brachial artery responses to endothelial-dependent (flow-mediated; dilation (FMD)) and independent (nitroglycerin mediated) stimuli. The nighttime drop in systolic BP (SBP) and diastolic BP (DBP) was less pronounced in UCRH than in CRH (SBP, 1.9±1.6 versus 4.9±1.7%; DBP, 7.5±1.8 versus 10.9±1.8%, UCRH and CRH, respectively; P<0.05). FMD was greater in control group compared with RHTN patients. Patients with UCRH had significantly impaired FMD compared with CRH (5.9±2.3% versus 7.1±5.1%; P<0.0001). Therefore, UCRH patients have less nocturnal dipping and a more impaired endothelial response compared with CRH patients. These findings suggest that important differences among patients with RHTN may allow identify subgroups with increased cardiovascular risk.

The physical ability of elderly female Japanese patients with cerebrovascular disease correlates with telomere length in their peripheral blood leukocytes

BACKGROUND AND AIMS

The telomere length of peripheral blood leukocytes has been reported to be inversely correlated with many kinds of pathophysiological conditions. However, correlations between telomere length in peripheral blood leukocytes and patients' physical ability are not known.

METHODS

To address this problem, the physical ability of patients with cerebrovascular disease admitted to the chronic disease ward of Kyushu University Hospital was assessed with the Barthel index (BI) and the telomere length of their peripheral blood leukocytes was determined.

RESULTS AND CONCLUSIONS

Women exhibited a significant correlation between the Barthel score and the expression of long telomeres (>9.4 Kb), in contrast with men who revealed no such correlation. The physical ability of older women was positively correlated with the lengths of their somatic telomeres. Among the BI items, the scores of more difficult physical performances tended to correlate with the presence of terminal restriction fragments longer than 9.4 Kb.

Growth in foetal life and infancy is associated with abdominal adiposity at the age of 2 years: the generation R study

OBJECTIVE

Early weight gain is associated with an increased risk of obesity. It is not known whether rapid weight gain in foetal life and infancy is also associated with increased abdominal adiposity. We examined the associations of foetal and postnatal growth characteristics with abdominal fat mass at the age of 2 years.

DESIGN

This study was performed in 481 children participating in a prospective cohort study from early foetal life onward.

MEASUREMENTS

Foetal and postnatal growth characteristics in second and third trimester, at birth and at the age of 2 years were related to abdominal fat mass (subcutaneous distance and area, preperitoneal distance and area) measured by ultrasound at the age of 2 years.

RESULTS

Foetal and birth weight were not associated with abdominal subcutaneous fat mass. Estimated foetal weight in second trimester of pregnancy was inversely associated with preperitoneal fat area [-3.73% (95% confidence interval -7.23, -0.10)] per standard deviation score increase in weight. Weight gain from birth to the age of 2 years was positively associated with preperitoneal fat mass measures. These associations remained significant after adjustment for age, sex, breastfeeding and body mass index. Positive associations were found between catch-up growth in weight and abdominal fat mass measures.

CONCLUSIONS

Our results suggest that rapid growth rates during foetal life and infancy are associated with increased abdominal subcutaneous and preperitoneal fat mass in healthy children. Further studies need to explore whether these associations persist in later life and are related to metabolic syndrome outcomes.

Abdominal fat in children measured by ultrasound and computed tomography

The prevalence of childhood obesity is increasing rapidly. Visceral fat plays an important role in the pathogenesis of metabolic and cardiovascular diseases. Currently, computed tomography (CT) is broadly seen as the most accurate method of determining the amount of visceral fat. The main objective was to examine whether measures of abdominal visceral fat can be determined by ultrasound in children and whether CT can be replaced by ultrasound for this purpose. To assess whether preperitoneal fat thickness and area are good approximations of visceral fat at the umbilical level, we first retrospectively examined 47 CT scans of nonobese children (body mass index <30kg/m(2); median age 7.9 y [95% range 1.2 to 16.2]). Correlation coefficients between visceral and preperitoneal fat thickness and area were 0.58 (p<0.001) and 0.76 (p<0.001), respectively. Then, to assess how preperitoneal and subcutaneous fat thicknesses and areas measured by ultrasound compare with these parameters in CT, we examined 34 nonobese children (median age 9.5 [95% range 0.3 to 17.0]) by ultrasound and CT. Ultrasound measurements of preperitoneal and subcutaneous fat were correlated with CT measurements, with correlation coefficients ranging from 0.75-0.97 (all p<0.001). Systematic differences of up to 24.0cm(2) for preperitoneal fat area (95% confidence interval -29.9 to 77.9cm(2)) were observed when analyzing the results described by the Bland-Altman method. Our findings suggest that preperitoneal fat can be used as an approximation for visceral fat in children and that measuring abdominal fat with ultrasound in children is a valid method for epidemiological and clinical studies. However, the exact agreement between the ultrasound and CT scan was limited, which indicates that ultrasound should be used carefully for obtaining exact fat distribution measurements in individual children.

Hostility is associated with visceral, but not subcutaneous, fat in middle-aged African American and white women

OBJECTIVE

To examine the cross-sectional association between hostility and measures of abdominal fat (visceral, subcutaneous) in middle-aged African American and white women. Because fat-patterning characteristics are known to differ by race, we were particularly interested in examining whether these associations were similar for women of both racial/ethnic groups.

METHODS

Participants were 418 (45% African American, 55% white) middle-aged women from the Chicago site of the Study of Women's Health Across the Nation. Visceral and subcutaneous fat were measured by computed tomographic scans and hostility was assessed via questionnaire. Multivariate linear regression models were conducted to test associations among race/ethnicity, hostility, and measures of abdominal fat.

RESULTS

In models adjusted for race/ethnicity and total percent fat, higher levels of hostility were associated with a greater amount of visceral fat (B = 1.8, standard error = 0.69, p = .01). This association remained significant after further adjustments for education, and multiple coronary heart disease (CHD) risk factors. Hostility was not associated with subcutaneous fat (p = .8). Although there were significant racial/ethnic differences in hostility (p < .001) and the amount of total body (p < .001), subcutaneous (p < .001) and visceral fat (p < .001), the associations between hostility and measures of abdominal fat did not differ for African American compared with white women (race/ethnicity x hostility interaction, p = .67 for visceral, p = .85 for subcutaneous).

CONCLUSIONS

Hostility may affect CHD risk in women via the accumulation of visceral fat. Despite significant black-white differences in fat patterning and overall CHD risk, the association between hostility and visceral fat seems to be similar for both African American and white women.

Sexual dimorphism of adipose tissue distribution across the lifespan: a cross-sectional whole-body magnetic resonance imaging study

BACKGROUND

Despite increasing research and clinical significance, limited information is available on how the visceral and subcutaneous adipose tissue (VAT and SAT) compartments develop during growth and maturation and then vary in volume across the adult lifespan. The present study aimed at exploring how adipose tissue compartments partition across the lifespan.

METHODS

Total body VAT and SAT were quantified in an ethnically-diverse cross-sectional sample of healthy subjects ages 5 - 88 yrs [children (5-17 years): males n = 88, BMI percentile (X ± SD), 61.9 ± 27.1; females, n = 59, BMI percentile, 60.0 ± 28.4; adults (≥ 18 yrs): males, n = 164, BMI, 25.6 ± 3.7 kg/m², and females, n = 188, BMI, 25.5 ± 5.4 kg/m²]. Subjects completed a whole-body magnetic resonance imaging scan and images were then segmented for VAT and SAT; total compartment volumes were calculated from respective slice areas. Sex and age distributions were evaluated by generating quadratic and cubic smoothing lines fitted to the data. Plots were developed with and without adjustment for total adipose tissue, ethnicity, and menopausal status in women. VAT and SAT volumes were both larger with greater age.

RESULTS

In adulthood, VAT was larger in males than in females with and without adjustment. In contrast, SAT volume was larger in females than in males after entering puberty and sex differences remained, with and without adjustment, across the remaining lifespan.

CONCLUSION

Based on observations made in this cross-sectional sample, VAT and SAT volumes were variably larger with greater age across most of the human lifespan, although the relatively small number of children warrants future larger scale studies to validate our observations. Moreover, the pattern and magnitude of adipose tissue "growth" differed between males and females, with the mechanistic basis of this sexual dimorphism only partially understood. These descriptive observations in a large cross-sectional cohort provide an initial foundation for future longitudinal and cohort studies.

Impact of abdominal fat and insulin resistance on arterial hypertension in non-obese women

OBJECTIVE: To evaluate the impact of abdominal fat and insulin resistance on arterial hypertension of non-obese women. METHODS:Thirty-five non-obese women (NO), age 35-68 years were studied, and divided into two groups according to the presence of hypertension (BP > 140 x 90 mmHg) ( HT = hypertensive; NT = normotensive). Leptin measurement and oral glucose tolerance test (OGTT) to assess insulin were performed in these patients. A CT-scan was used to evaluate visceral (VF) and subcutaneous abdominal fat (SCF). The Central fat distribution index (CDI) was proposed to evaluate the impact of subcutaneous abdominal fat on central fat distribution in hypertensive patients. RESULTS: When compared to NT-NO (n = 17) group, HT-NO (n = 18) showed higher blood pressure levels (systolic and diastolic), greater VF area (84.40 ± 55.70 versus 37.50 ± 23.00 cm²; p = 0.036), greater SCF area (174.30 ± 83.00 versus 79.80 ± 27.40 cm²; p = 0.030), higher HOMAr index (1.59 ± 0.72 versus 0.93 ± 0.48 mmol.mU/L²; p = 0.006), higher CDI index (12.67 ± 7.04 versus 6.19 ± 2.57 cm²/kg) and higher leptin level (19.1 ± 9.6 versus 7.4 ± 3.5 ng/mL; p = 0.028). CONCLUSIONS: Arterial hypertension in non-obese women is associated with insulin resistance, central fat distribution and higher leptin levels.

Gender aspects of the role of the metabolic syndrome as a risk factor for cardiovascular disease

BACKGROUND

The interaction of the risk factors of abdominal obesity, disturbed glucose homeostasis, dyslipidemia, and hypertension is believed to represent a distinct entity, termed the metabolic syndrome (MetS), that leads to a greater increase in cardiovascular risk than does the sum of its components.

OBJECTIVE

We reviewed currently available information regarding gender differences in the role of the MetS as a risk factor for cardiovascular disease (CVD).

METHODS

Using the search terms women, men, sex, gender, sex differences, and gender differences in combination with the metabolic syndrome, we conducted a systematic review of the available literature on sex differences in the MetS. The National Institutes of Health, PubMed, and MEDLINE databases were searched retrospectively from 2007 to 1987. Reference lists of identified articles were also used as a source, and articles were not restricted to the English language.

RESULTS

In recent years, the MetS has been more prevalent in men than in women but has risen particularly in young women, where it is mainly driven by obesity. Diagnostic criteria for the MetS vary for the cutoff points and definition of its components in a gender-specific manner. Based on the definition of impaired glucose homeostasis and pathologic abdominal circumference or waist/hip ratio, more or fewer women are included. Glucose and lipid metabolism are directly modulated by estrogen and testosterone, with a lack of estrogen or a relative increase in testosterone inducing insulin resistance and a proatherogenic lipid profile. Hypertension is a strong risk factor in both sexes, but the prevalence of hypertension increases more rapidly in aging women than in men. Menopause and polycystic ovary syndrome contribute to the development of MetS by the direct effects of sex hormones. Some components of the MetS (eg, diabetes and hypertension) carry a greater risk for CVD in women.

CONCLUSIONS

Future gender-related clinical and research activities should focus on the identification of sex- and gender-specific criteria for risk management in patients with the MetS. We propose small, focused, mechanistic studies on sex-specific surrogate end points and sex-specific studies in animal models for diabetes and aging.

Effect of a weight loss intervention on anthropometric measures and metabolic risk factors in pre- versus postmenopausal women

BACKGROUND

The present study examines changes in body weight, fat mass, metabolic and hormonal parameters in overweight and obese pre- and postmenopausal women who participated in a weight loss intervention.

METHODS

Seventy-two subjects were included in the analysis of this single arm study (premenopausal: 22 women, age 43.7 +/- 6.4 years, BMI 31.0 +/- 2.4 kg/m2; postmenopausal: 50 women, age 58.2 +/- 5.1 years, BMI 32.9 +/- 3.7 kg/m2). Weight reduction was achieved by the use of a meal replacement and fat-reduced diet. In addition, from week 6 to 24 participants attended a guided exercise program. Body composition was analyzed with the Bod Pod(R). Blood pressures were taken at every visit and blood was collected at baseline and closeout of the study to evaluate lipids, insulin, cortisol and leptin levels.

RESULTS

BMI, fat mass, waist circumference, systolic blood pressure, triglycerides, glucose, leptin and cortisol were higher in the postmenopausal women at baseline. Both groups achieved a substantial and comparable weight loss (pre- vs. postmenopausal: 6.7 +/- 4.9 vs 6.7 +/- 4.4 kg; n.s.). However, in contrast to premenopausal women, weight loss in postmenopausal women was exclusively due to a reduction of fat mass (-5.3 +/- 5.1 vs -6.6 +/- 4.1 kg; p < 0.01). In premenopausal women 21% of weight loss was attributed to a reduction in lean body mass. Blood pressure, triglycerides, HDL-cholesterol, and glucose improved significantly only in postmenopausal women whereas total cholesterol and LDL-cholesterol were lowered significantly in both groups.

CONCLUSION

Both groups showed comparable weight loss and in postmenopausal women weight loss was associated with a pronounced improvement in metabolic risk factors thereby reducing the prevalence of metabolic syndrome.

Non-dipping blood pressure in the metabolic syndrome among Arabs of the Oman family study

OBJECTIVE

The objective was to examine the circadian changes in blood pressure and their relation to the metabolic syndrome and its components in Omani Arabs.

RESEARCH METHODS AND PROCEDURES

Ambulatory blood pressure (ABPM) was recorded in 1124 subjects from 5 large, extended, consanguineous, and young Arab pedigrees. According to the International Diabetes Federation's definition, 264 subjects had the metabolic syndrome, a prevalence of 23%. Subjects were defined as non-dippers when their nocturnal systolic blood pressure (SBP) fell by <10% from daytime SBP.

RESULTS

Non-dippers with the metabolic syndrome were 131 of 264 (50%), compared with 265 of 860 (31%) without the metabolic syndrome. Of the non-dippers, 99 of 131 (76%) were females and 32 of 131 (24%) were males. Daytime and nighttime SBP and DBP and nighttime pulse pressure were significantly higher in non-dipper subjects with the metabolic syndrome. The important determinants of a non-dipping BP in this cohort were high BMI and high serum triglycerides.

DISCUSSION

We hypothesize that obesity and nocturnal volume-dependent hypertension may be involved in the pathophysiology of non-dipping in the metabolic syndrome. This study showed that non-dipping BP was common in subjects with the metabolic syndrome. Higher 24-hour blood pressure load may add to the indices of the overall cardiovascular burden already associated with the metabolic syndrome.

Generalised and abdominal obesity and risk of diabetes, hypertension and hypertension–diabetes co-morbidity in England

Objectives

To look at trends in generalised (body mass index (BMI) ≥30 kg m–2) and abdominal (waist circumference (WC) >102 cm in men, >88 cm in women) obesity among adults between 1993 and 2003, and to evaluate their association with diabetes, hypertension and hypertension–diabetes co-morbidity (HDC) in England.

Design

Analyses of nationally representative cross-sectional population surveys, the Health Survey for England (HSE).

Subjects

Non-institutionalised men and women aged ≥35 years.

Measurements

Interviewer-administered questionnaire (sociodemographic information, risk factors, doctor-diagnosed diabetes), measurements of height and weight to calculate BMI. WC and blood pressure measurements were taken by trained nurses.

Results

Generalised obesity increased among men from 15.8% in 1993 to 26.3% in 2003, and among women from 19.3% to 25.8%. Abdominal obesity also increased in both sexes (men: 26.2% in 1993 to 39.0% in 2003; women: 32.4% to 47.0%). In 1994, 1998 and 2003, generalised and abdominal obesity were independently associated with risk of hypertension, diabetes and HDC. The odds of diabetes associated with generalised obesity in 1994, 1998 and 2003 were 1.62, 2.26 and 2.62, respectively, in women and 1.24, 1.82 and 2.10, respectively, in men. Similar differences were observed for hypertension and HDC. Men and women with abdominal obesity also showed a higher risk for diabetes, hypertension and HDC than those with a normal WC.

Conclusions

If current trends in obesity continue then the risk of related morbidities may also increase. This will impact on cardiovascular disease morbidity and mortality, with cost implications for the health service. Therefore there is an urgent need to control the epidemic of obesity.