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The role of obesity in the pathogenesis of heart failure (HF), and in particular HF with preserved ejection fraction (HFpEF), has drawn significant attention in recent years. The prevalence of both obesity and HFpEF has increased worldwide over the past decades and when present concomitantly suggests an obese‐HFpEF phenotype. Anthropometrics, including body mass index, waist circumference, and waist‐to‐hip ratio, are associated with incident HFpEF. However, the cardiovascular effects of obesity may actually be driven by the distribution of fat, which can accumulate in the epicardial, visceral, and subcutaneous compartments. Regional fat can be quantified using non‐invasive imaging techniques, including computed tomography, magnetic resonance imaging, and dual‐energy X‐ray absorptiometry. Regional variations in fat accumulation are associated with different HFpEF risk profiles, whereby higher epicardial and visceral fat have a much stronger association with HFpEF risk compared with elevated subcutaneous fat. Thus, regional adiposity may serve a pivotal role in the pathophysiology of HFpEF contributing to decreased cardiopulmonary fitness, impaired left ventricular compliance, upregulation of local and systemic inflammation, promotion of neurohormonal dysregulation, and increased intra‐abdominal pressure and vascular congestion. Strategies to reduce total and regional adiposity have shown promise, including intensive exercise, dieting, and bariatric surgery programmes, but few studies have focused on HFpEF‐related outcomes among obese. Further understanding the role these variable fat depots play in the progression of HFpEF and HFpEF‐related hospitalizations may provide therapeutic targets in treating the obese‐HFpEF phenotype. [ABSTRACT FROM AUTHOR]

Summary: Objective: Research findings on the relationship between serum androgens and adipose tissue in older females are inconsistent. We aimed to clarify the relationship using state‐of‐the‐art techniques to evaluate associations between body fat distribution and plasma testosterone (T) levels in older postmenopausal women. Design: Observational, cross‐sectional study of healthy, community dwelling postmenopausal women. Patients and Measurements: Postmenopausal women (60‐80 years old) were included in this study. Overall body composition was evaluated by dual‐energy X‐ray absorptiometry. Abdominal and thigh fat depots were measured by magnetic resonance imaging. Circulating T concentrations were analysed by liquid chromatography‐tandem mass spectrometry. Results: Thirty‐five women (66.6 ± 0.8 years) participated in this study. T levels were positively associated with clinical proxy measures of adiposity including weight (ρ = 0.39), BMI (ρ = 0.43) and waist circumference (ρ = 0.39) (all P < 0.05). Fat mass and % body fat were correlated with T levels (ρ = 0.42 and 0.38 respectively, both P < 0.05). T correlated with overall and superficial abdominal fat (ρ = 0.34 and 0.37 respectively, both P < 0.05) but not with visceral adipose tissue. T increased with greater thigh fat (ρ = 0.49, P < 0.05) in both superficial and deep depots (ρ = 0.50 and 0.35 respectively, both P < 0.05). Conclusion: Our results suggest that postmenopausal women with higher circulating T levels have both higher regional and overall body adiposity. These findings underscore the sexual dimorphism in the relationship between serum androgen levels and adiposity. [ABSTRACT FROM AUTHOR]

Many athletes seek to optimize body composition to fit the physical demands of their sport. American football requires a unique combination of size, speed, and power. The purpose of the current study was to evaluate longitudinal changes in body composition in Division I collegiate football players. For 57 players (mean ± SD, age = 19.5 ± 0.9 years, height = 186.9 ± 5.7 cm, weight = 107.7 ± 19.1 kg), body composition was assessed via dual-energy x-ray absorptiometry in the off-season (March- Pre), end of off-season (May), mid-July (Pre-Season), and the following March (March-Post). Outcome variables included weight, body fat percentage (BF%), fat mass, lean mass (LM), android and gynoid (GYN) fat, bone mineral content (BMC), and bone mineral density (BMD). For a subset of athletes (n = 13 out of 57), changes over a 4-year playing career were evaluated with measurements taken every March. Throughout a single year, favorable changes were observed for BF% (Δ = -1.3 ± 2.5%), LM (Δ = 2.8 ± 2.8 kg), GYN (A = -1.5 ± 3.0%), BMC (Δ = 0.06 ± 0.14 kg), and BMD (Δ = 0.015 ± 0.027 g⋅cm-2, all p ≤ 0.05). Across 4 years, weight increased significantly (Δ = 6.6 ± 4.1 kg) and favorable changes were observed for LM (Δ = 4.3 ± 3.0 kg), BMC (Δ = 0.1 8 ± 0.1 7 kg), and BMD (Δ = 0.033 ± 0.039 g⋅-2, all p ≤ 0.05). Similar patterns in body composition changes were observed for linemen and non-linemen. Results indicate that well-trained collegiate football players at high levels of competition can achieve favorable changes in body composition, even late in the career, which may confer benefits for performance and injury prevention. [ABSTRACT FROM AUTHOR]

Equine metabolic syndrome (EMS) is a clinical syndrome, the components of which are increased adiposity, hyperinsulinaemia and insulin dysregulation resulting in a predisposition to developing laminitis. It has been described as EMS because it has many similarities to metabolic syndrome in man, which designates a set of risk factors which predispose to coronary heart disease and type 2 diabetes mellitus. The aim of this article is to describe the diagnosis and management of EMS in ambulatory practice. [ABSTRACT FROM AUTHOR]

Objective: Vital exhaustion (VE) is more strongly associated with cardiovascular disease (CVD) risk for women than men. This study examined whether sex differences in associations of VE with CVD risk markers are accounted for by unique associations of VE with regional adiposity.Methods: The study enrolled 143 persons (18-55 years) without diagnosed conditions. VE was assessed by the Maastricht questionnaire. CVD indices were measured using the euglycemic-hyperinsulinemia clamp, resting blood pressure, and blood draws. Regional adiposity was measured using computed tomography and 2-D echocardiography. This cross-sectional study employed a path analysis approach, including relevant covariates.Results: Of the cohort, aged 38.7 ± 8.4 years, 65% were men, and 41% were obese. The final model had excellent fit (χ2(36) = 36.5, p = .45; RMSEA = 0.009, CFI = 0.999). For women, but not men, the model indicated paths from VE to: 1) lower insulin sensitivity (B = -0.10, p = .04), and higher total cholesterol to HDL ratio (B = 0.12, p = .09), triglycerides (B = 0.10, p = .08), and C-reactive protein (B = 0.08, p = .09) through visceral adiposity; 2) higher mean arterial pressure (B = 0.14, p = .04), lower insulin sensitivity (B = -0.09, p = .08), and higher C-reactive protein (B = 0.12, p = .07) through subcutaneous adiposity; 3) lower insulin sensitivity (B = -0.07, p = .08) and higher total cholesterol to HDL ratio (B = 0.16, p = .03) through liver adiposity; and 4) higher C-reactive protein (B = 0.08, p = .09) through epicardial adiposity.Conclusion: Results extend prior evidence by showing that the association of VE with CVD risk in women is linked with specific regional adiposity elevation. Further study of adiposity-related mechanisms in women who experience early decline in vitality may inform clinical targets for CVD prevention. [ABSTRACT FROM AUTHOR]

Background: Menarche seems be related to the relative distribution rather than the total amount of body fat. Previous studies showed that the ratio between lower-body vs. upper-body fat was associated with the timing of menarche. Aim: To compare the relative distribution of subcutaneous fat among Bengali Hindu pre-.and post-menarcheal girls. Materials and Methods: The participants were 234 Bengali Hindu girls aged 11-14 years: 111 pre-menarcheal and 123 post-menarcheal girls, randomly selected from a secondary school from a suburb of Kolkata, West Bengal, India. Triceps, abdominal, sub-scapular, and calf skinfolds were measured. For each skinfold site, ratio was calculated as follows: Log (one skinfold/sum of skinfolds). Principal components (PC) analysis was performed to derive components which express the maximum contrast among the log of ratios. T-test was employed to assess differences between individual scores of components between pre-.and post-menarcheal girls. Results: The three identified PC suggested extremities-trunk, lower trunk-upper trunk, and an upper extremity-lower extremity contrasts, respectively. Scores for second and third components showed significant differences between pre- and post-menarcheal groups of girls. Conclusion: The attainment of menarche by Bengali girls aged 11-14 years was associated with characteristically more relative subcutaneous fat distribution in the upper trunk and in the lower limbs, in contrast to lower trunk and upper limbs, respectively. [ABSTRACT FROM AUTHOR]

Estrogen has direct effects within adipose tissue and has been implicated in regional adiposity; however, the influence of estrogen on in vivo lipolysis is unclear. The purpose of this study was to investigate the effect of local 17β-estradiol (E2) on subcutaneous adipose tissue (SAT) lipolysis in premenopausal women. In vivo lipolysis (dialysate glycerol) was measured in 17 women (age 27.4 ± 2.0 yr, BMI 29.7 ± 0.5 kg/m²) via microdialysis of abdominal (AB) and gluteal (GL) SAT. Glycerol was measured at baseline and during acute interventions to increase lipolysis including local perfusion of isoproterenol (ISO, β-adrenergic agonist, 1.0 μmol/l), phentolamine (PHEN, β-adrenergic antagonist, 0.1 mmol/l), and submaximal exercise (60%VO2peak, 30 min); all with and without coperfusion of E2 (500 nmol/l). E2 coperfusion blunted the lipolytic response to ISO in AB (E2 196 ± 31%, control 258 ± 26%, P = 0.003) but not in GL (E2 113±14%, control 111±12%, P = 0.43) adipose tissue. At rest, perfusion of PHEN with ISO did not change dialysate glycerol. Submaximal exercise during ISO + PHEN increased dialysate glycerol in the AB (56 ± 9%) and GL (62 ± 12%) regions. Probes perfused with E2 during exercise and ISO + PHEN had an increased lipolytic response in AB (90 ± 9%, P = 0.007) but a lower response in GL (35 ± 7%, P = 0.05) SAT compared with no-E2 conditions. E2 effects on lipolysis are region specific and may work through both adrenergic and adrenergic-independent mechanisms to potentiate and/or blunt SAT lipolysis in premenopausal women. [ABSTRACT FROM AUTHOR]

Objectives To study the relationships between muscle mass, regional adiposity, and adipokines and glucose disposal in an older population. Design Cross-sectional analysis. Setting Community-dwelling volunteers from the Baltimore Longitudinal Study of Aging. Participants Two hundred eighty men and 259 women with a mean age of 71.1 ± 0.4 (range 55-96) and complete data on fasting plasma adiponectin and leptin, oral glucose tolerance test ( OGTT) (plasma glucose available at 0, 20, 40, 60, 80, 100, and 120 minutes), thigh computed tomography ( CT), physical activity levels, and anthropometric measures. Measurements Participants were classified into eight groups according to the presence of global adiposity (body mass index > 27 kg/m2), central adiposity (waist circumference > 88 cm for women and > 102 cm for men), and low muscle mass ( CT thigh, lowest sex-specific tertile (93.8 cm2 in women and 110.7 cm2 in men) of adjusted thigh muscle area). Linear regression models were used to estimate the contribution of these eight groups to early glucose area under the curve ( AUC) ( t = 0-40 minutes), late glucose AUC ( t = 60-120 minutes), and total glucose AUC ( t = 0-120 minutes) from the OGTT. Results Regardless of muscle mass, individuals with a combination of central and global adiposity were more likely to have delayed glucose disposal rates ( P < .05). A strong negative association was also found between circulating adiponectin levels and glucose disposal rates (early AUC, β = −0.14; late AUC, β = −0.20; and total AUC, β = −0.20; P < .05 for all three AUCs) after adjusting for regional adiposity, muscle mass, circulating leptin levels, physical activity, age, and sex. Conclusion Older individuals with global and central adiposity may be at risk of glucose intolerance unrelated to low muscle mass. [ABSTRACT FROM AUTHOR]

The article presents a consensus statement on equine metabolic syndrome (EMS). Similar to the metabolic syndrome (MetS) in humans, the principal components of EMS include obesity, insulin resistance (IR) and laminitis in horses and ponies. To diagnose EMS, a complete history of the patient should be obtained, in addition to performing a physical examination, taking radiographs of the feet and conducting laboratory tests.

Objective: Computed tomography (CT) is widely used in humans for the assessment of regional body composition. It was particularly helpful in establishing the metabolic complications associated with high visceral fat volume. Physicists have only recently developed microCT systems dedicated to small animal imaging, with adequate resolution and dose delivery, but precision, accuracy and reproducibility remain to be determined. Methods: We determined visceral and subcutaneous adipose tissue volume in living mice by microCT and, after euthanasia, by immersing the dissected fat pads into water and measuring the volume displaced. The precision of each method was determined as well as overall agreement and limits of confidence between both techniques. Results: Bland-Altman analysis showed good limits of agreement between both methods and that microCT only slightly overestimated visceral and subcutaneous fat volumes (respectively, by 0.29±0.29 cm3 representing 3.5% of the average visceral fat volume and 0.07±0.05 cm3, ie 2.7% of the average subcutaneous fat volume) as compared to the water displacement method. Furthermore, the precision of microCT allowed a detection of a difference between animals in fat pad volumes of only 0.10 cm3 with a power of 80% and a statistical probability of 0.02 (approximately equal to 0.09 g ie 0.8% of the average fat pad mass). Conclusion: We showed that microCT is currently one of the most sensitive methods for assessing adipose tissue depots in small mammals in vivo, with discrimination between different fat depots. This technique allows highly quantitative measurements, small coefficient of variation and the capability for serial measurements in the same living animal [ABSTRACT FROM AUTHOR]

BMI has been recommended for evaluating over-weight and obesity in children and adolescents in the clinical setting. Definitions of overweight and obesity are based on percentile cutoff points. There are both strengths and limitations of BMI for this use. The strengths include the fact that BMI is cheap and relatively easy to use. The weaknesses include the fact that BMI percentiles are not widely used, and categorization of BMI percentiles may not adequately define risk of comorbid conditions. In addition, percentiles are not optimal for stratifying children and adolescents with very high BMI. Alternatives to the use of BMI and BMI percentiles include waist circumference to evaluate regional fat deposition and replacement of percentiles with z scores. Despite limitations, BMI and BMI percentiles have great utility in the clinical setting and the potential to be even more useful as BMI is used more frequently and more appropriately by primary care providers. Additional research on alternatives or adjuncts to BMI is needed. [ABSTRACT FROM AUTHOR]

Abstract: The hypotheses were: HISS-dependent insulin resistance (HDIR) accounts for insulin resistance that occurs with aging; HDIR is the initiating metabolic defect that leads progressively to type 2 diabetes and the metabolic syndrome; a synergistic antioxidant cocktail in chow confers protection against HDIR, subsequent symptoms of diabetes, and the metabolic syndrome. Male Sprague Dawley rats were tested at 9, 26, and 52 weeks to determine their dynamic response to insulin, the HISS (hepatic insulin sensitizing substance)-dependent component of insulin action, and the HISS-independent (direct) insulin action using a dynamic insulin sensitivity test. In young rats, the HISS component accounted for 52.3±2.1% of the response to a bolus of insulin (50mU/kg) which decreased to 29.8±3.4% at 6 months and 17.0±2.7% at 12 months. HISS action correlated negatively with whole body adiposity and all regional fat depots (r 2 =0.67–0.87). The antioxidants (vitamin C, vitamin E, and S-adenosylmethionine) conferred protection of HISS action, fat mass at all sites, blood pressure, postprandial insulin and glucose. Data are consistent with the hypotheses. Early detection and therapy directed towards treatment of HDIR offers a novel therapeutic target. [Copyright &y& Elsevier]

Objective:The aim of this study was to determine the ability of dual X-ray absorptiometry (DXA) to detect exogenous fat in men and women simulating typical sex-specific weight changes.Subjects:A diverse sample including 29 elderly (52–83 years) and 61 young (18–40 years) individuals (45 women, 45 men) of varying body mass index (BMI; M±s.d.: 26.1±4.9 kg/m2, range=16.4–39 kg/m2).Methods:Whole body (WB) DXA scans (Hologic QDR 4500A) were completed with Scan 1 performed as a normal baseline scan, Scan 2 with 1 kg packet of lard placed on each thigh and Scan 3 with two 1 kg lard packets placed on the abdomen (men) or chest and abdomen (women).Results:Measurement error of fat mass (FM) was more pronounced in the trunk as lard packets were detected with 59% accuracy (error=0.82±0.42 kg, P<0.001), whereas 94% of thigh lard (error=0.11±0.45 kg, P<0.001) was determined to be FM, while the remainder in both conditions was determined to be mineral free lean mass. Initial FM (r=0.37, P<0.001) for thigh loading and trunk bone mineral content (r=0.30, P<0.01) for trunk-loaded conditions had the most impact on measurement error of WB FM.Conclusions:Regional differences impact measurement error of simulated changes in FM with greater measurement error in the trunk compared to the thigh region and initial FM and higher levels of bone mineral content in the trunk region impacting error.European Journal of Clinical Nutrition (2008) 62, 553–559; doi:10.1038/sj.ejcn.1602770; published online 25 April 2007 [ABSTRACT FROM AUTHOR]

The article offers information whether effects of increasing and decreasing exercise levels are symmetric in weight gain and weight loss. According to the author, changes in adiposity are compared with the running distances at baseline and follow-up in men and women whose reported exercise increased or decreased during the 7.7 years of follow up. He emphasized that due to the reductions of weekly exercise in men and women, weight gain may not be reversed by resuming prior activity. Moreover, men's exercise threshold for symmetric weight change with changing exercise levels has been agreed by the IOM guidelines.

The article presents a prospective study which examines the hypothesis that long-term maintenance of vigorous activity, particularly running, attenuates age-related weight gain. The subjects of the study were 6,119 male and 2,221 female runners whose running distances changed after years. Based on the follow-up survey of these individuals, both sexes increased their body weight and waist circumference as their running intervals changed over time. According to the authors, both men and women gained less weight relative to the level of their vigorous activity.

Objective:To determine prospectively whether physical activity can prevent age-related weight gain and whether changing levels of activity affect body weight.Design/subjects:The study consisted of 8080 male and 4871 female runners who completed two questionnaires an average (±standard deviation (s.d.)) of 3.20±2.30 and 2.59±2.17 years apart, respectively, as part of the National Runners’ Health Study.Results:Changes in running distance were inversely related to changes in men's and women's body mass indices (BMIs) (slope±standard error (s.e.): −0.015±0.001 and −0.009±0.001 kg/m2 per Δkm/week, respectively), waist circumferences (−0.030±0.002 and −0.022±0.005 cm per Δkm/week, respectively) and percent changes in body weight (−0.062±0.003 and −0.041±0.003% per Δkm/week, respectively, all P<0.0001). The regression slopes were significantly steeper (more negative) in men than women for ΔBMI and Δ%body weight (P<0.0001). A longer history of running diminished the impact of changing running distance on men's weights. When adjusted for Δkm/week, years of aging in men and years of aging in women were associated with increases of 0.066±0.005 and 0.056±0.006 kg/m2 in BMI, respectively, increases of 0.294±0.019 and 0.279±0.028% in Δ%body weight, respectively, and increases of 0.203±0.016 and 0.271±0.033 cm in waist circumference, respectively (all P<0.0001). These regression slopes suggest that vigorous exercise may need to increase 4.4 km/week annually in men and 6.2 km/week annually in women to compensate for the expected gain in weight associated with aging (2.7 and 3.9 km/week annually when correct for the attenuation due to measurement error).Conclusions:Age-related weight gain occurs even among the most active individuals when exercise is constant. Theoretically, vigorous exercise must increase significantly with age to compensate for the expected gain in weight associated with aging.International Journal of Obesity (2006) 30, 543–551. doi:10.1038/sj.ijo.0803172; published online 29 November 2005 [ABSTRACT FROM AUTHOR]

Introduction/Purpose: Data from vigorously active women (runners) suggested that declines in adiposity with weekly running distance were nonlinear and dependent on whether the women are relatively lean or fat. The purpose of the current study is to assess the cross-sectional relationship between the amount of moderate-intensity physical activity (walking distance) and indicators of adiposity. Methods: Cross-sectional analyses (i.e., quadratic polynomial regression, regression for percentiles of adiposity) of body mass index (BMI), body circumferences, and bra cup sizes in 27,596 women. Results: The estimated percent reductions between walking 40-50 km·wk-1 and < 10 km·wk-1 were greatest for BMI, intermediate for waist circumference and cup size, and least for hip and chest circumferences. The relationships of walking distance to SMI and body circumferences were all nonlinear (convex). In addition, the inverse relationship between weekly walking distance and adiposity was greatest at the highest percentile of BMI, body circumferences, and cup size, and least at the lowest percentiles. Thus, the decline in adiposity per kilometer per week increment in walking distance was greatest in overweight mostly sedentary women and least in lean active women. The decline in SMI per kilometer per week of exercise was greater in the walkers than previously reported for runners. However, based on the relationships between walking distance and percentiles of the BMI distribution reported here, we show that the majority of this difference is attributable to the leanness of the runners and greater fatness of the walker. Conclusion: These data suggest that in women the greatest benefit of walking may be among the most obese and that at higher weekly distances the declines in weight associated with walking diminish. Whether these relationships are causal remains to be determined. [ABSTRACT FROM AUTHOR]

Although it is known that triglyceride concentrations increase with adiposity, whether the same increase applies for different percentiles of the triglyceride distribution has not been reported. Therefore, physican-supplied triglyceride concentrations from 7288 male and 2326 female runners were divided into strata according to the body mass index (BMI) and circumferences of the waist, hip and chest. The percentiles of the triglyceride distribution within each stratum were used to determine the cross-sectional regression slope between adiposity and triglyceride levels at each triglyceride percentile.Compared to the 5th percentile of the triglyceride distribution, the rise in men’s triglycerides at the 95th percentile per unit of adiposity was 14-fold greater for BMI, 7.8-fold greater for waist circumference, 3.6-fold greater for hip circumference, and 4.4-fold greater for chest circumference. The rise in women’s triglyceride concentrations at the 95th percentile was 8-fold greater than at the 5th percentile for each kg/m2 increase in BMI.These results suggest that the metabolic effects of adiposity on plasma triglycerides depend upon whether the concentrations are high or low. This contradicts statistical assumptions upon which prior studies of adiposity have based their analyses. We speculate that the reported greater increases in triglycerides per unit of adiposity in whites than blacks, in men than women, and in low-density lipoprotein (LDL) pattern B than A are all consistent with the relationships we observe. It remains to be verified whether these relationship also apply to less active populations. [Copyright &y& Elsevier]

Discusses that obesity is a serious and rapidly increasing public health issue in many developed and developing countries. Risk factors associated with obesity; Effects of peroxisome proliferator- activated receptor gamma on body fat distribution; Impact of obesity on metabolism in man and women.

OBJECTIVE: To compare Canadians of Aboriginal (First Nation, FN) and European ancestry (EA), with respect to obesity, subcutaneous fatness and relative subcutaneous fat distribution. DESIGN: Cross-sectional comparison. SUBJECTS: 118 First Nation and 472 European ancestry Canadians from Northern Ontario, youth (5–19 y) and adults (20–75 y). MEASUREMENTS: Stature, mass and skinfold thicknesses at the triceps, biceps, medial calf, subscapular, suprailiac and abdominal sites. ANALYSIS: Prevalence of obesity was determined using the 85th percentile of body mass index (BMI) from NHANES II as the cut-off. Principal components (PC) analyses were performed on the six skinfolds. The first component (PC1) represented a trunk-extremity skinfold contrast. Differences in mean component scores between FN and EA were assessed using independent samples t-tests. RESULTS: Prevalence of obesity among FN was high, ranging from 29% in youth to 60% in adult females. FN demonstrated greater subcutaneous adiposity and greater values for PC1, with the exception of adult males, where the difference is in the expected direction, but is not significant. The direction of the differences indicates that the FN have a greater centralization of subcutaneous fat. CONCLUSIONS: FN Canadians generally have a greater prevalence of obesity, greater subcutaneous fatness and a more centralized distribution of body fat than those of European ancestry. [ABSTRACT FROM AUTHOR]