Associations Of Body Fat Distribution Research Articles

Body fat distribution, fat-free mass and cardiovascular function in the UK Biobank

Abstract Background Excess adiposity and high body mass index have been associated with cardiac dysfunction and heart failure. However, the role of whole body imaging and independent associations of regional fat and fat-free mass on left ventricular and vascular function is unclear. Purpose This study determined the cross-sectional associations of regional fat depots and fat-free mass on left ventricular function and arterial stiffness to explain obesity-related cardiac dysfunction. Methods Participants who underwent whole body magnetic resonance imaging (MRI) and dual energy X-ray absorptiometry (DXA) in an ongoing imaging study of 100,000 individuals in the UK were included in this analysis. Analyses exclude individuals with major cardiac and vascular diseases at initial baseline assessment. Regional fat distribution was quantified using MRI while body fat-free mass was quantified with DXA. Cardiac MRI was used to measure left ventricular (LV) ejection fraction and LV mass while pulse wave velocity from finger photo-plethysmography was used to measure arterial stiffness index. Associations of body fat distribution (visceral fat, abdominal subcutaneous fat, other body fat) and fat-free mass with each of LV ejection fraction, LV mass and arterial stiffness index, after mutual adjustment for one another and potential confounders were determined using multivariable linear regression. Results We included 31,088 individuals (mean age 63.4 years, 53% women). Among regional body fat measures, higher visceral fat was associated with lower LVEF (β=-0.43; 95% CI: -0.55, -0.31 per SD) and higher arterial stiffness index (β=0.44; 95% CI: 0.34, 0.54 per SD) while none of the regional fat and fat-free mass showed significant association with LV function or arterial stiffness. None of the fat or fat-free mass measures showed significant association with LV mass. These associations were not explained by inflammatory markers, blood pressure or glycaemic profile. Conclusion Visceral fat is the main driver of obesity-related cardiac and vascular dysfunction. There is need for further studies to understand the biological causal pathways of obesity-heart disease.Figure 1Figure 2

Association of body fat distribution with all-cause and cardiovascular mortality in US adults: a secondary analysis using NHANES

ObjectiveTo investigate the association of fat and lean mass in specific regions with all-cause and cardiovascular-related mortality.DesignPopulation based cohort study.SettingUS National Health and Nutrition Examination Survey (2003–2006 and 2011–2018).Participants22 652...

Association of body fat distribution with high blood pressure among Chinese children and adolescents with various nutritional status: a population-based study

Association of body fat distribution with high blood pressure among Chinese children and adolescents with various nutritional status: a population-based study

Television viewing and body fat distribution among Bengali school children of Kolkata, India

Background: Childhood obesity is considered as a major concern since a couple of decades. The increasing prevalence of childhood obesity is clear and concerns about the future health impact of childhood obesity are currently well documented. Low level of physical activity, high quantity of fat rich junk food consumption and prolonged leisure time with television (TV) viewing were reported to be significantly associated with obesity.
 Objective: The present study aims to evaluate the association of body fat distribution with television watching among school going Bengali children of Kolkata, India.
 Sample and Methods: 200 girls (aged 10-15 years) from a very heterogeneous background were selected from one state school. Data on socio-demographic aspects, TV viewing, computer use, physical activity and dietary pattern were collected by pretested questionnaire after obtaining prior consent from competent persons. Anthropometric measurements were taken following standard techniques.
 Results: Most of the participants preferred fat rich junk food and a few practice regular exercises. One-way ANOVA showed significant differences of body mass index (BMI), waist circumference (WC) and mid upper arm circumference (MUAC) between groups depending on the duration of TV viewing. The adiposity related variables were standardized by standard deviation score before the inferential analyses. Adjusted multiple linear regression showed positive effects of the duration of TV viewing on BMI (R2=0.233) and MUAC (R2=0.277).
 Conclusion: Irrespective of economic status, prolonged television watching leads to an adverse body fat distribution among teenage girls of Kolkata.

Association of Body Fat Distribution and Risk of Breast Cancer in Pre- and Postmenopausal Women

Introduction: Obesity is a risk factor for both the development of and mortality from breast cancer in postmenopausal but not in premenopausal women. However, which part of the fat mass is associated with risk remains unclear, and whether the difference in the risk for breast cancer is associated with discrepancy in the distribution of fat with menstrual status requires further study. Methods: A dataset from the UK Biobank, which included 245,009 female participants and 5,402 females who developed breast cancer during a mean follow-up of 6.6 years, was analyzed. Body fat mass was measured according to bioelectrical impedance at baseline by trained technicians. Age- and multivariable-adjusted hazard ratios and corresponding 95% confidence intervals for associations between body fat distribution and the risk for breast cancer were estimated using Cox proportional-hazards regression. Height, age, education level, ethnicity, index of multiple deprivation, alcohol intake, smoking, physical activity, fruit consumption, age at menarche, age at first birth, number of births, hormone replacement therapy, family history of breast cancer, hysterectomy, and ovariotomy were adjusted for potential confounders. Results: Fat distribution differed between pre- and postmenopausal women. After menopause, there was an increase in fat mass in different body segments (arms, legs, and trunk). After age- and multivariable adjustment, fat mass in different segments, BMI, and waist circumference were significantly associated with the risk for breast cancer among postmenopausal but not premenopausal women. Conclusion: Postmenopausal women exhibited more fat in different body segments, which are associated with increased risk for breast cancer, compared to premenopausal women. Fat mass control throughout the body may be beneficial in mitigating the risk for breast cancer and was not limited to abdominal fat alone among postmenopausal women.

Association between body composition and blood pressure in normal-weight Chinese children and adolescents

BackgroundThe aim of this study was to assess the associations of body fat distribution and lean body mass (LBM) with blood pressure (BP) in normal-weight Chinese children and adolescents.MethodsA total of 898 normal-weight Chinese children and adolescents, aged 10–18 years, were included this cross-sectional study via a cluster sampling method. The bioelectrical impedance analysis (BIA) was used to measure body composition. The participants were measured for blood pressure (BP) using a calibrated electronic sphygmomanometer according to the standard method by the "American Hypertension Education Project Working Group".ResultsBody composition was related to abnormal BP in normal-weight children and adolescents. After the model adjusted for age, smoking, and drinking, regression analysis showed that fat mass percentage (FMP) was negatively associated with abnormal BP, while LBM was positively associated with abnormal BP in boys(P < 0.05). Whereas FMP and visceral fat level (VFL) were positively associated with abnormal BP in girls (P < 0.05).ConclusionsThere are sex differences in the relationships between total body fat, visceral fat and lean body mass with abnormal BP in normal-weight youths. Therefore, it is of great significance to pay attention to the relative influence of the body composition of the boys and girls in the prevention and treatment of hypertension in youths.

Determinants of Metabolic Syndrome and Type 2 Diabetes in the Absence of Obesity: The Jackson Heart Study.

ContextMultiple studies suggest that adults who were normal weight at diabetes diagnosis are at higher risk for all-cause mortality than those who had overweight or obesity at diagnosis.ObjectiveWhile obesity is a known risk factor for cardiometabolic disease, differences in body fat distribution in those without obesity are understudied, especially in African Americans.MethodsIn 1005 participants of the Jackson Heart Study, without cardiovascular disease at baseline, we used logistic regression to investigate the longitudinal association of body fat distribution by CT scan with metabolic syndrome (MetS) or type 2 diabetes (T2D). We used the harmonized International Diabetes Federation criteria to define MetS. We included only normal weight or overweight participants (BMI: 18.5 to < 30.0 kg/m2). We created separate models for MetS and T2D adjusted for a standard set of covariates. We excluded participants with prevalent MetS or T2D, respectively in sensitivity.ResultsHigher visceral fat, subcutaneous fat, BMI, and insulin resistance (HOMA-IR) were significantly associated with MetS and T2D after adjustment. Visceral fat was strongly associated with both outcomes (MetS OR = 2.07 [1.66-2.68]; T2D OR = 1.51 [1.21-1.88]), and the association for MetS persisted in the normal weight only group. Estimates were robust to sensitivity analysis and were only modestly mediated by insulin resistance. Physical activity was not associated with MetS or T2D.ConclusionVisceral fat is strongly associated with developing MetS, even in normal weight individuals, suggesting that excess visceral fat plays a role in cardiometabolic risk beyond that of overall adiposity and obesity in African Americans.

Body fat distribution in trunk and legs are associated with cardiometabolic risk clustering among Chinese adolescents aged 10–18 years old

Abstract Objectives The aim of the present study was to evaluate the association of body fat distribution with cardiometabolic risk factors clustering among Chinese adolescents. Methods In this cross sectional study a total of 1,175 adolescents aged 10–18 years underwent a comprehensive assessment of cardimetabolic risk factors. Body fat analysis was performed with bioelectrical impedance analysis (BIA). Results Individuals with the CVRFs≥1 or CVRFs≥2 had higher indices of body fat distribution such as body fat mass (BFM) compared to those with normal CVRFs (all p&lt;0.001). The prevalence of CVRFs≥1, CVRFs≥2 increased with increasing of the quartile of BFM, TBFM, ABFM, LBFM, PBF, VFL compared to normal subjects. After adjusted for age and sex, the study indicated an linear relationship between TBFM (β = 0.693, 95% CI:0.363, 1.023), LBFM (β = −1.471, 95% CI:−2.768, −0.175) and CVRFs z-score. Logistic regression models suggested TBFM was associated with CVRFs≥1 and CVRFs≥2 by higher odds. Lower odds of LBFM was associated with CVRFs≥2. Conclusions The contribution of the fat mass in specific region on the cardiovascular risk factors clustering is different among adolescents. The trunk fat is associated with higher clustered cardiometabolic risk, while leg fat mass is the protective factor.

ASSOCIATION BETWEEN BODY FAT DISTRIBUTION AND BLOOD PRESSURE IN NORMAL-WEIGHT CHINESE CHILDREN AND ADOLESCENTS

Objective: Body fat distribution is commonly considered as playing a significant role in blood pressure (BP), whether normal-weight children and adolescents whose body fat distribution confer BP risk that remains uncertain. Aim of this study was to assess the associations of body fat distribution with BP risk in normal-weight Chinese children and adolescents. Design and method: A cross-sectional study consisted of 898 normal-weight children and adolescents aged 10–18 years from China. Participants were selected using a cluster sampling method and underwent bioelectrical impedance analysis (BIA) for body fat distribution indexes. Results: Body fat distribution was related with an increased risk for BP in normal-weight children and adolescents. After adjustment for gender and age, visceral fat level(VFL) was positively associated with abnormal BP (OR:1.109 95%CI, 1.016–1.210; P &lt; 0.05), and the same result also found when including fat mass percentage(FMP; P &lt; 0.05). FMP, VFL and VFL/FMP ratio showed a positively association with abnormal BP in girls after adjustment for age, respectively (OR:1.08; 95%CI, 1.03–1.13; P &lt; 0.01)(OR:1.22; 95%CI, 1.07–1.38; P &lt; 0.01)(OR:1.08; 95%CI, 1.01–1.14; P &lt; 0.05). However, when both FMP and VFL were adjusted for age, FMP but not VFL negatively associated with abnormal BP in boys (OR:0.94; 95%CI,0.88–1.00; P &lt; 0.05), and the same result also found when additional including VFL/FMP ratio in the same model(P &lt; 0.05). Conclusions: The body fat distribution (especially visceral fat) is associated with abnormal BP in normal-weight children and adolescents, especially in girls. Therefore, attention should be paid to the relative effect of body fat distribution (especially visceral fat) on BP in the prevention and treatment of hypertension in youths.

Association of body fat distribution and metabolic syndrome with the occurrence of colorectal adenoma: A case-control study.

Visceral fat is thought to play different roles in the carcinogenesis of the colon with peripheral fat. Our aim was to evaluate the association of body fat distribution measured by bioelectrical impedance analysis (BIA) with the incidence of colorectal adenoma (CRA). A total of 410 asymptomatic participants who underwent a screening colonoscopy from July 2017 to December 2019 in our center were recruited, including 230 with adenomas and 180 without detected adenomas. The participants' body fat was measured by BIA, including their body fat mass (BFM), body fat percentage (BFP), and waist-to-hip ratio. Parameters of metabolic syndrome (MetS), including waist circumference, blood pressure, fasting blood glucose (FBG), blood level of triglyceride, cholesterol, and high-density lipoprotein were measured as well. According to univariate analysis, age, male sex, body mass index, waist circumference, BFM, waist-to-hip ratio, blood pressure, and FBG were higher in the adenoma group than in the adenoma-free group (P < 0.05). On multivariate logistical analysis (adjusted for age, sex, smoking, drinking, and family history of CRC), a high waist-to-hip ratio was associated with a high incidence of CRA (odds ratio [OR] 1.84, 95% confidence interval [CI] 1.09-3.09, P = 0.02). Only a large waist circumference in components of MetS was independently associated with the incidence of CRA (OR 1.90, 95% CI 1.17-3.08, P = 0.01) in the multivariate analysis. Body fat distribution is associated with CRA, central obesity is a core risk factor for CRA in MetS. Chinese Clinical Trial Registration number: ChiCTR-RRC-17010862.

Body Fat Distribution, Overweight, and Cardiac Structures in School-Age Children: A Population-Based Cardiac Magnetic Resonance Imaging Study.

BackgroundAdiposity is associated with larger left ventricular mass in children and adults. The role of body fat distribution in these associations is not clear. We examined the associations of body fat distribution and overweight with cardiac measures obtained by cardiac magnetic resonance imaging in school‐age children.Methods and ResultsIn a population‐based cohort study including 2836 children, 10 years of age, we used anthropometric measures, dual‐energy X‐ray absorptiometry, and magnetic resonance imaging to collect information on body mass index, lean mass index, fat mass index, and abdominal visceral adipose tissue index. Indexes were standardized by height. Cardiac measures included right and left ventricular end‐diastolic volume, left ventricular mass, and mass‐to‐volume ratio as a marker for concentricity. All body fat measures were positively associated with right and left ventricular end‐diastolic volumes and left ventricular mass, with the strongest associations for lean mass index (all P<0.05). Obese children had a 1.12 standard deviation score (95% CI, 0.94–1.30) larger left ventricular mass and a 0.35 standard deviation score (95% CI, 0.14–0.57) higher left ventricular mass‐to‐volume ratio than normal weight children. Conditional on body mass index, higher lean mass index was associated with higher right and left ventricular end‐diastolic volume and left ventricular mass, whereas higher fat mass measures were inversely associated with these cardiac measures (all P<0.05).ConclusionsHigher childhood body mass index is associated with a larger right and left ventricular size. This association is influenced by higher lean mass. In childhood, lean mass may be a stronger determinant of heart growth than fat mass. Fat mass may influence cardiac structures at older ages.

The impact of visceral and general obesity on vascular and left ventricular function and geometry: a cross-sectional magnetic resonance imaging study of the UK Biobank

Aims We aimed to evaluate the associations of body fat distribution with cardiovascular function and geometry in the middle-aged general population.Methods and results Four thousand five hundred and ninety participants of the UK Biobank (54% female, mean age 61.1 ± 7.2 years) underwent cardiac magnetic resonance for assessment of left ventricular (LV) parameters [end-diastolic volume (EDV), ejection fraction (EF), cardiac output (CO), and index (CI)] and magnetic resonance imaging for body composition analysis [subcutaneous adipose tissue (SAT) and visceral adipose tissue (VAT)]. Body fat percentage (BF%) was assessed by bioelectrical impedance. Linear regressions were performed to assess the impact of visceral (VAT) and general (SAT and BF%) obesity on cardiac function and geometry. Visceral obesity was associated with a smaller EDV [VAT: β −1.74 (−1.15 to −2.33)], lower EF [VAT: β −0.24 (−0.12 to −0.35), SAT: β 0.02 (−0.04 to 0.08), and BF%: β 0.02 (−0.02 to 0.06)] and the strongest negative association with CI [VAT: β −0.05 (−0.06 to −0.04), SAT: β −0.02 (−0.03 to −0.01), and BF% β −0.01 (−0.013 to −0.007)]. In contrast, general obesity was associated with a larger EDV [SAT: β 1.01 (0.72–1.30), BF%: β 0.37 (0.23–0.51)] and a higher CO [SAT: β 0.06 (0.05–0.07), BF%: β 0.02 (0.01–0.03)]. In the gender-specific analysis, only men had a significant association between VAT and EF [β −0.35 (−0.19 to −0.51)].Conclusion Visceral obesity was associated with a smaller LV EDV and subclinical lower LV systolic function in men, suggesting that visceral obesity might play a more important role compared to general obesity in LV remodelling.

Body fat distribution, in particular visceral fat, is associated with cardiometabolic risk factors in obese women.

BackgroundBody fat distribution is, next to overall obesity, an important risk factor for cardiometabolic outcomes in the general population. In particular, visceral adipose tissue (VAT) is strongly associated with cardiometabolic risk factors. Since it is unclear whether body fat distribution is also important in men and women with obesity we investigated the associations between measures of body fat distribution and cardiometabolic risk factors in men and women with obesity.MethodsIn this cross-sectional analysis of obese men and women (BMI≥30 kg/m2) included in the Netherlands Epidemiology of Obesity Study, waist:hip ratio(WHR), waist circumference, and MRI-based abdominal subcutaneous adipose tissue (aSAT) and VAT were determined. Associations between measures of body fat distribution and presence of ≥1 risk factor, such as hypertension or hypertriglyceridemia, were examined using logistic regression analyses; stratified by sex and adjusted for age, ethnicity, education, tobacco smoking, alcohol consumption, physical activity and depending on the association additionally for total body fat or VAT.ResultsWe included 2,983 obese individuals (57% women) with a mean age of 56 and standard deviation (SD) of 6 and mean BMI of 34.0 kg/m2 (4.0), after exclusion of individuals with missing values of cardiometabolic risk factors (n = 33). 241 individuals were obese without other cardiometabolic risk factors. In obese women, all measures of body fat distribution except aSAT (OR per SD:0.76, 95%CI: 0.53, 1.10) were associated with having ≥1 cardiometabolic risk factor, of which VAT most strongly associated (5.77; 3.02, 11.01). In obese men, associations of body fat distribution and the presence of cardiometabolic risk factors were attenuated. (e.g. VAT:1.42; 0.84, 2.41).ConclusionsIn obese women, but less so in men, measures of body fat distribution, of which VAT most strongly, are associated with cardiometabolic risk factors.

Association of body fat distribution and carotid intima media thicknesss with Vitamin D in obese premenopausal women

Searchable abstracts of presentations at key conferences in endocrinology ISSN 1470-3947 (print) | ISSN 1479-6848 (online)

Abstract 22: Influence of Smoking and Sex on Genetic Associations of Body Fat Distribution: The Giant (Genetic Investigation of ANthropometric Traits) Consortium

Visceral fat and smoking are important risk factors for CVD and other long-term poor health outcomes. Central adiposity is frequently assessed in population studies using waist-to-hip ratio adjusted for BMI (WHRadjBMI). Genome-wide association studies (GWAS) have discovered loci that influence WHRadjBMI, sometimes with sex-specific effects. However, we do not know whether and how smoking behavior influences the association between genetic variants and WHRadjBMI. Our study investigates the influence of smoking and genetic variants on WHRadjBMI, with particular consideration for differential effects by sex. Forty-one GIANT GWAS (108,397 participants) were used to investigate the influence of smoking on SNP WHRadjBMI associations using sex-stratified models considering SNP main effects adjusted for smoking status, and SNP main effects stratified by smoking status. Results from each study were meta-analyzed using an inverse-variance weighted fixed-effects model for men and women separately as well as combined. A total of 19 SNPs reached genome-wide significance (p&lt;5x10-8) having adjusted the SNP effect for smoking across strata (women, men, and combined), including 11 previously reported WHRadjBMI loci. For known WHRadjBMI loci, the influence of smoking varied by sex. In women, four known WHRadjBMI SNPs (TBX15, DNM3, RSPO3, and ADAMTS9) had a greater effect in smokers vs. nonsmokers (TBX15: β(SE) = 0.0506 (0.014), p = 3.84x10-4) vs. β(SE) = 0.0382 (0.0072), p = 1.14x10-7). Three of these (TBX15, DNM3, RSPO3) have been previously associated with tobacco use disorder (TUD). In men, three known WHRadjBMI loci (ADAMTS9, DNM3, ZNRF3) had a greater effect among smokers vs nonsmokers (ZNRF3: β(SE) = 0.0365 (0.0148), p = 1.37x10-2) vs β(SE) = 0.0192 (0.0088), p = 12.87x10-2). Eight of our 19 top SNPs have not been previously associated with WHRadjBMI (within 500 kb). Of these eight loci, distinct patterns of association by smoking and sex were again noted. In addition, one locus (ABCA1) has been previously associated with TUD. In addition to identifying novel loci associated with body fat distribution, these findings underscore the importance of considering the effect of smoking when investigating the genetics of obesity related phenotypes and emphasize the need to consider sex separately when studying the effects of smoking on body fat distribution.

Genome-wide association of body fat distribution in African ancestry populations suggests new loci.

Central obesity, measured by waist circumference (WC) or waist-hip ratio (WHR), is a marker of body fat distribution. Although obesity disproportionately affects minority populations, few studies have conducted genome-wide association study (GWAS) of fat distribution among those of predominantly African ancestry (AA). We performed GWAS of WC and WHR, adjusted and unadjusted for BMI, in up to 33,591 and 27,350 AA individuals, respectively. We identified loci associated with fat distribution in AA individuals using meta-analyses of GWA results for WC and WHR (stage 1). Overall, 25 SNPs with single genomic control (GC)-corrected p-values<5.0×10−6 were followed-up (stage 2) in AA with WC and with WHR. Additionally, we interrogated genomic regions of previously identified European ancestry (EA) WHR loci among AA. In joint analysis of association results including both Stage 1 and 2 cohorts, 2 SNPs demonstrated association, rs2075064 at LHX2, p = 2.24×10−8 for WC-adjusted-for-BMI, and rs6931262 at RREB1, p = 2.48×10−8 for WHR-adjusted-for-BMI. However, neither signal was genome-wide significant after double GC-correction (LHX2: p = 6.5×10−8; RREB1: p = 5.7×10−8). Six of fourteen previously reported loci for waist in EA populations were significant (p<0.05 divided by the number of independent SNPs within the region) in AA studied here (TBX15-WARS2, GRB14, ADAMTS9, LY86, RSPO3, ITPR2-SSPN). Further, we observed associations with metabolic traits: rs13389219 at GRB14 associated with HDL-cholesterol, triglycerides, and fasting insulin, and rs13060013 at ADAMTS9 with HDL-cholesterol and fasting insulin. Finally, we observed nominal evidence for sexual dimorphism, with stronger results in AA women at the GRB14 locus (p for interaction = 0.02). In conclusion, we identified two suggestive loci associated with fat distribution in AA populations in addition to confirming 6 loci previously identified in populations of EA. These findings reinforce the concept that there are fat distribution loci that are independent of generalized adiposity.

Genome-Wide Association of Body Fat Distribution in African Ancestry Populations Suggests New Loci

Genome-Wide Association of Body Fat Distribution in African Ancestry Populations Suggests New Loci

Diabetes and Nonalcoholic Fatty Liver Disease

Diabetes and Nonalcoholic Fatty Liver Disease

Association of Body Fat Distribution with Proinflammatory Gene Expression in Peripheral Blood Mononuclear Cells from Young Adult Subjects

Peripheral blood mononuclear cells (PBMC) measurements have proved useful in recent studies to discern peripheral biomarkers for common complex diseases and for understanding host responses to drugs and nutrition in personalized medicine. Despite the initial promising data from PBMC, there is little information, however, on inflammatory and immune gene regulation in the context of body fat distribution and metabolic features in healthy adults. We investigated the putative association of body fat distribution and related-metabolic features with mRNA levels of proinflammatory markers in PBMC. This study enrolled 136 healthy subjects (85 females/51 males; age: 21.5 +/- 2.5 years). Anthropometrical, clinical, metabolic, and proinflammatory variables were assessed with validated tools. Interestingly, in normal-weight subjects with lower truncal fat (TF) values, mRNA levels of ICAM1, IL1R1, IL6, and TNF-alpha in PBMC were lower (p < 0.05), compared to normal-weight individuals with higher TF (>58.5/50.2% for men/women, respectively) and overweight/obese subjects [body mass index (BMI) >25 kg/m(2)]. After regression analyses were performed, individuals with the highest tertiles of TF and waist circumference displayed higher mRNA gene expressions as well as circulating proinflammatory (C-reactive protein and IL6) and metabolic (blood pressure, HOMA-IR, and LDL-c:HDL-c ratio) variables values (p < 0.05), independent from gender. Our findings collectively suggest that the mRNA expression of certain proinflammatory markers in PBMC is associated with body fat distribution in healthy adult subjects, which in turn, was also related to metabolic features and plasma proinflammatory markers concentrations.

Body composition and fat distribution influence systemic hemodynamics in the absence of obesity: the HyperGEN Study

We have shown that increased cardiac output is related to both fat-free mass and fat mass in obesity. We studied the association of body fat distribution and body composition with flow-resistance relations in overweight. We studied 521 overweight, nonobese participants in the Hypertension Genetic Epidemiology Network (HyperGEN) Study-a component of the National Heart, Lung, and Blood Institute Family Blood Pressure Program, designed to assess the genetic basis of hypertension. Participants had normal ventricular function and no cardiovascular disease: 261 with central fat distribution (CFD) (waist girth >88 cm in women and >102 cm in men) and 260 with peripheral fat distribution (PFD). Fat-free mass (FFM) and fat mass (FM) were measured by bioelectric impedance. Body composition was estimated as FM/FFM. Echocardiographic stroke volume (SV) and cardiac output (CO) were measured. Hypertension was present in 73% of the subjects with PFD and in 78% with CFD. Overweight with CFD was associated with greater FM/FFM in both normotensive and hypertensive participants. After FFM, age, sex, and race were controlled for, SV and CO were higher in subjects overweight with CFD than in those with PFD, whereas peripheral resistance was not significantly different. Differences in CO between CFD and PFD were reduced after further adjustment for FM. After the covariates were controlled for, hypertensive subjects had higher peripheral resistance and lower arterial compliance than did normotensive participants, but cardiac output was not significantly different. CFD is associated with more severe abnormalities in body composition and with higher CO independently of FFM in overweight, nonobese subjects.