Peripheral Body Fat Distribution Research Articles

Central and peripheral body fat distribution: Different associations with low-grade inflammation in young adults?

Background and aimsEvidence regarding the impact of regional body fat distribution on low-grade inflammation is limited. The current study examined the association of central and peripheral body fat distribution and low-grade inflammation levels in young adults, considering collinearity between variables. Methods and resultsA cross-sectional analysis of 809 adults (aged 27 years) was conducted as part of the EPITeen cohort, Porto, Portugal. Regional body fat was measured by dual-energy X-ray absorptiometry scan (DXA) and serum high-sensitivity C-reactive protein (hsCRP) was measured in a fasting blood sample. OLS (ordinary least squares) and LASSO (least absolute shrinkage and selection operator) regression models were fitted to estimate the association of trunk and peripheral fat with hsCRP, stratified by sex. Using OLS regression, trunk fat in females was positively associated with ln(hsCRP) (β1 = 0.064, 95% CI 0.018; 0.109). The effect of peripheral fat on ln(hsCRP) was shown not to be significantly different from trunk fat (β2 = −0.011, 95% CI −0.110; 0.089), but no statistically significant association was observed (β3 = 0.053, 95% CI −0.004; 0.110) between peripheral fat and ln(hsCRP). In males, trunk fat also showed a positive association with ln(hsCRP) (β1 = 0.104, 95% CI 0.055; 0.154), and the effect of peripheral fat on ln(hsCRP) was shown to be significantly different from trunk fat (β2 = −0.124, 95% CI −0.237;−0.011). However, the association between peripheral fat and ln(hsCRP) did not reach statistical significance (β3 = −0.020, 95% CI −0.086; 0.046). The results of OLS were confirmed by LASSO regression. ConclusionA higher fat deposited in the trunk was positively associated with hsCRP, whereas no statistically significant effect was observed for peripheral fat.

Central and Peripheral Body Fat Distribution on Insulin Resistance of Young Obese Women

Studies have shown that excess of fat in central region is the main substrate for pathophysiological alterations that leads obesity‐associated insulin resistance. Lately, in the medical practice the use of the waist circumference (WC) instead waist‐to‐hip ratio (WHR) is more usual. We hypothesized that WHR is a better tool to infer insulin resistance in young obese women. The aim of this study was to evaluate the insulin‐sensitive/insulin‐resistant in young obese women within central and peripheral body fat distribution. We studied 61 young obese women (BMI 30 to 40 kg/m2) with WC ≥ 88 cm and without comorbidities. They were divided into: with central fat distribution (CF), defined as waist‐to‐hip ratio (WHR) ≥ 0.85 cm (n=30, 33±7 y), and with peripheral fat distribution (PF) with WHR < 0.85 cm (n=31, 33±6 y). All volunteers were submitted to anthropometric, glycemic and insulin measurements and indexes: fasting, HOMA‐IR, QUICKI and area under the curve (AUC) during the Oral Glucose Tolerance Test (OGTT) to assess the insulin sensitivity. Despite the fat distribution, CF and PF shown similar anthropometric measures (weight= 86.8±8.5 vs.87.6±8.3 kg, WC= 109±6 vs.106±8 cm, BMI= 33.2±2.7 vs. 33.7±2.4 kg/m2; respectively, p>0.05). Also, both obese groups, CF and PF, showed normal fasting glucose (84±10 vs. 82±10 mg/dL, p=0.420), based in the IDF criteria (<100mg/dL). However, the group CF compared with PF presented elevated fasting insulin (17.8±8.2 vs. 12.6±6.8 uUI/mL, p=0.008), HOMA‐IR (3.7±1.9 vs. 2.6±1.6 uUI/mL, p=0.011), reduced QUICKI (0.322±0.025 vs. 0.340±0.025, p=0.007). Furthermore, the group CF compared with PF had lower insulin sensitivity as AUCglucose/AUCinsulin ratio from OGTT (1.42±0.67 vs. 2.12±0.86, p=0.001). In conclusion, our data demonstrated that in young obese women with similar WC and fasting glucose, the central body fat distribution increase insulin‐resistant, emphasizing the importance in used the waist‐to‐hip ratio as important tool for identify the additional risk factor in obesity young women.Support or Funding Information#Universidade Nove de Julho (UNINOVE), SP ‐ Brazil.This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.

Body Fat Accumulation is Associated with Early Arterial Changes in HIVInfected Children

Background: Antiretroviral therapy (ART) has greatly improved clinical outcomes in human immunodeciency virus (HIV) infection in adults and children. However, emerging data link ART to clinical lipodystrophy and premature atherosclerosis. We examined the impact of body fat changes on blood pressure and endothelial function in HIV infected children with and without ART. Methods: Central and peripheral body fat distribution was assessed in 68 HIV infected children. In all children blood pressure was measured and high resolution ultrasound was used to determine endothelium dependent dilatation (flow mediated dilatation-FMD) in the brachial artery. Results: From the 68 HIV infected children, 46 were on ART. There was no evidence of clinical lipodystrophy with ART in this cohort. Total cholesterol was increased in children on ART (p<0.001). FMD was significantly lower in those on ART compared to antiretroviral naive children (p<0.01). Increased BMI and waist as well as peripheral body circumference measurements in the arm and thigh were associated with higher systolic blood pressure (p<0.05 and p<0.01 respectively). An inverse association was noted between peripheral body composition measurements (zcalf and zthigh) and FMD (p<0.05 for both). Conclusion: HIV-infected children on ART have deranged lipids and evidence of early arterial abnormalities. Increased body fat accumulation is associated with reduced endothelial function and elevated blood pressure in HIVinfected children. These findings suggest that healthy dietary intake and weight control would be advisable in HIV infected children for optimal vascular disease prevention.

Body size and endometriosis: results from 20 years of follow-up within the Nurses' Health Study II prospective cohort

Is there a relationship between body mass index (BMI), body shape and endometriosis? Endometriosis is inversely associated with early adult BMI and may correlate with a peripheral body fat distribution. The literature suggests an inverse relation between endometriosis and BMI, although few studies have specifically explored this association in depth. Prospective cohort study using data collected from 116 430 female nurses from September 1989 to June 2011 as part of the Nurses' Health Study II cohort. PARTICIPANTS/MATERIALS, METHODS AND SETTING: Cases were restricted to laparoscopically confirmed endometriosis. Weight at age 18 and height were reported at baseline, and current weight was updated every 2 years. Waist and hip measurements were first taken in 1993 and updated in 2005. Rate ratios (RR) and 95% confidence intervals (CI) were calculated using Cox proportional hazards models with time-varying covariates. A total of 5504 incident cases of endometriosis were reported during 1 299 349 woman-years (incidence rate = 385 per 100 000 woman-years). BMI at age 18 and current BMI were each significantly inversely associated with endometriosis (P-value, test for linear trend <0.0001). Both associations were stronger among infertile women. Obese infertile women with current BMIs of 35-39.9 kg/m(2) and ≥ 40 kg/m(2) had a 55% (95% CI 0.30-0.67) and a 62% (95% CI 0.23-0.62) lower risk of endometriosis, respectively, compared with the low-normal BMI referent (18.5-22.4 kg/m(2)). Rates of endometriosis were nearly 3-fold higher in women with waist-to-hip ratios <0.60 (RR = 2.78, 95% CI 1.38-5.60) compared with those with waist-to-hip ratios between 0.70 and 0.79, although the sample size for this category was very small. Although women with undiagnosed endometriosis certainly remain in the comparison population even in this prospective cohort study, the community prevalence of endometriosis in an asymptomatic population is very low. Moreover, the characteristics of this small proportion of undiagnosed cases are diluted among the >90 000 women accurately defined as being endometriosis-free and are, therefore, unlikely to impact on effect estimation. Although geographically diverse, the NHS II cohort is overwhelmingly Caucasian, which may limit generalizability to more ethnically diverse populations. WIDER IMPLICATIONS OF THE STUDY: The results of this study suggest that endometriosis is inversely associated with early adult BMI and may correlate with a peripheral body fat distribution.

Adrenergic Overdrive as the Link Among Hypertension, Obesity, and Impaired Thermogenesis

The sympathetic nervous system plays a pivotal role in both blood pressure and metabolic homeostatic control by regulating cardiac output, peripheral vascular resistance, heat production, and resting metabolic rate, which accounts for a large fraction of adult energy expenditure. Throughout the years, the attractive hypothesis based on this evidence has been advanced that an alteration in blood pressure regulation, as well as in thermogenesis control exerted by the sympathetic nervous system, represents the pathogenetic background for 2 diseases of common detection in current clinical practice, that is, hypertension and obesity, respectively. As far as high blood pressure is concerned, a number of studies based on indirect or direct methodologic approaches to assess neuroadrenergic function have unequivocally demonstrated that a hyperactivity of the sympathetic nervous system contributes at the development, maintenance, and progression of the hypertensive state.1–4 They have also shown that neurogenic mechanisms favor the genesis of hypertension-related end organ damage, that is, left ventricular hypertrophy, arterial and arteriolar hypertrophy, and vascular remodelling.5,6 Even when blood pressure is normal, an adrenergic overdrive has also been reported in the obese state,7,8 and independent but additive increases in sympathetic activity have been described when obesity is coupled with hypertension.9 Traditionally, obesity-related hypertension has been regarded, at least in part, as the result of a hyperactivity of the sympathetic nervous system, related to some extent to the weight-associated increase in sympathetic cardiovascular drive.9,10 …

Effect of central and peripheral body fat distribution on sympathetic and baroreflex function in obese normotensives

Previous studies have shown that obesity is characterized by a sympathetic overactivity coupled with an insulin resistance state and a baroreflex impairment. The present study was set out to compare the effects of peripheral versus central obesity on sympathetic, metabolic and reflex function. In 36 lean subjects (age 35.8 +/- 1.4 years, mean +/- SEM), 20 subjects with peripheral obesity (PO) and 26 subjects with central obesity (CO), all age-matched and with normal blood pressure values, we measured beat-to-beat arterial blood pressure (Finapres), heart rate (HR, ECG), homeostasis model assessment (HOMA) index, plasma norepinephrine (NE, high-performance liquid chromatography) and postganglionic muscle sympathetic nerve traffic (MSNA, microneurography) at rest and during baroreceptor stimulation and deactivation induced by stepwise intravenous infusions of phenylephrine and nitroprusside, respectively. Both HOMA index, NE and MSNA values were significantly increased (P < 0.01) in obese as compared with lean individuals. Subjects with CO displayed MSNA and HOMA values significantly greater than those found in individuals with PO (65.4 +/- 2.0 versus 47.9 +/- 1.9 bs/100hb and 2.85 +/- 0.10 versus 2.43 +/- 0.11 a.u., respectively, P < 0.05 for both). Both in male and female subjects with CO or PO, MSNA, HOMA index and waist-to-hip ratio were significantly related to each other. Baroreceptor-HR and -MSNA control was significantly (P < 0.01) impaired in obese as compared with lean subjects, the degree of impairment being similar in CO and PO. These data suggest that CO is characterized by a sympathetic activation greater for magnitude than that detectable in PO. This appears not to be related to gender or to baroreflex mechanisms but rather to metabolic factors, i.e. to the greater insulin resistance characterizing CO.

Hyperviscosity and microproteinuria in central obesity: relevance to cardiovascular risk.

To investigate the role of blood rheology changes in the occurrence of glomerular proteinuria in obese patients with central fat distribution. Fifty-nine obese out-patients (31 with central and 28 with peripheral body fat distribution) and 24 healthy subjects. Blood and plasma viscosity (Rotational viscometer CV100 HAAKE), erythrocyte deformability (whole-blood filtration time), fibrinogen (nephelometry), urinary excretion rates of albumin, IgG, transferrin and IgA (nephelometry). Higher blood viscosity (at low and high shear-rates), plasma viscosity, fibrinogen, erythrocyte aggregability and lower erythrocyte deformability were found in patients with central obesity than in patients with peripheral obesity (P < 0.01) and in healthy subjects (P < 0.001). Furthermore an increased urinary excretion rate of albumin (P < 0.001), IgG (P < 0.001), transferrin (P < 0.01) and IgA (P < 0.05) was found in patients with central obesity than in the other two groups. Blood hyperviscosity (at shear-rate 1 s-1 and 1/200 ratio) significantly correlated with the amount of urinary excretion of proteins independently of the other clinical and metabolic variables. The data demonstrated haemorheologic disorders related to pathologic proteinuria in patients with central obesity. The interaction between these two components may increase the risk of widespread cardiovascular disease.

Body fat distribution has weight-independent effects on clinical, hormonal, and metabolic features of women with polycystic ovary syndrome

This study was performed to investigate whether different patterns of body fat distribution may have distinct effects on the clinical, hormonal, and metabolic features of women with clinical hyperandrogenism such as polycystic ovary syndrome (PCOS). Ninety-seven consecutive women with PCOS were included in the study after assessment of gynecological and obesity history and careful clinical examination. Women were divided into three tertile groups based on the waist to hip ratio (WHR). Those with peripheral body fat distribution (P-BFD) had a WHR of less than 0.80, those with intermediate body fat distribution (I-BFD) had a WHR of 0.81 to 0.90, and those with abdominal body fat distribution (A-BFD) had a WHR exceeding 0.90. Baseline blood and urine samples were obtained for several hormone and lipid determinations, and the response of glucose, insulin, and C-peptide to a glucose oral challenge (75 g) was investigated. In the PCOS group, WHR values were higher than those used to define P-BFD and A-BFD in the normal female population. As WHR values increased, a significantly greater prevalence of obesity and acanthosis nigricans and a lower prevalence of acne was present. No significant differences were present in any of the other clinical features between the three groups. Ovarian morphology and volumes were similar in all groups. After adjusting for age and body mass index, we found that increasing WHR values led to (1) a progressive and significant increase of luteinizing hormone (LH), androstenedione, and estrone concentrations; (2) higher levels of fasting and glucose-stimulated insulin, whereas no difference was present in fasting and stimulated glucose and C-peptide concentrations; (3) significantly higher levels of triglycerides, very-low-density lipoprotein (VLDL) cholesterol, and apolipoprotein B and lower values of high-density lipoprotein (HDL) cholesterol without any difference in total cholesterol and apolipoprotein A-I. In addition, women with A-BFD had significantly higher diastolic blood pressure levels than the other two groups. This study therefore demonstrates that among women with PCOS, those with A-BFD have different clinical, hormonal, and metabolic features when compared with women with P-BFD, and that these differences were independent of individual body weight.

The hypothalamic-pituitary-adrenal axis in obese women with different patterns of body fat distribution.

To investigate whether obese subjects with abdominal obesity may be characterized by hyperactivity of the hypothalamic-pituitary-adrenal axis, we examined two groups of obese women with a waist to hip ratio (WHR) lower than 0.80 (n = 13), therefore having peripheral body fat distribution (P-BFD), or a WHR higher than 0.85 (n = 12), thus having abdominal body fat distribution (A-BFD). A group of seven normal weight healthy women served as controls. All subjects underwent the following protocol study that included 1) measurement of daily urinary free cortisol excretion rate; 2) a CRF test (human CRF, 1 microgram/kg BW, as iv bolus), with blood samples taken at regular intervals for ACTH and cortisol determination; and 3) an ACTH test, performed by administering two boli of ACTH (Synacthen, 0.2 microgram/kg BW, iv), at 90-min intervals, with blood samples taken for cortisol determination. Each woman also had a control saline study. Basal levels of both ACTH and cortisol rose significantly after CRF administration in all groups, but this increase was significantly higher in A-BFD than in P-BFD and control women. A significant correlation was found between the incremental area of cortisol and that of ACTH during the CRF test (r = 0.502), but not between these parameters and WHR values. Although the cortisol increase after the ACTH test was higher in A-BFD than in the other groups, these differences were only significant at 60 min during the test and when the analysis for repeated measures was applied. On the contrary, the incremental cortisol area after the ACTH test was not significantly different in the three groups. Moreover, it was not significantly correlated with the incremental cortisol area after CRF test or WHR values. Daily urinary free cortisol excretion rates (per g creatinine), however, were significantly higher in A-BFD than in P-BFD and control women. These results, therefore, suggest that obese women with A-BFD may have hyperactivity of the hypothalamic-pituitary-adrenal axis. This abnormality could be central in origin, due to hypersecretion of CRF or ACTH; alternatively, it could represent an adaptive phenomenon secondary to a state of functional cortisol resistance.

Body Fat Distribution and Breast Cancer in the Framingham Study

We examined the relation between central body fat distribution and breast cancer in a prospective cohort of women who participated in the Framingham Study. At the baseline examination in 1948, a total of 2,201 women aged 30-62 years were analyzed. An index of central to peripheral body fat (the central adiposity ratio) was calculated from the sum of the trunkal skinfolds (chest, subscapular, and abdominal) divided by the sum of the extremity skinfolds (triceps and thigh). These skinfolds were measured at the fourth examination in 1954. The cohort was followed for up to 28 years and yielded 106 cases of breast cancer. When divided into quartiles based on the central adiposity ratio, only women in the fourth quartile (those with the highest central to peripheral body fat distribution) demonstrated an increased risk for breast cancer. The age- and adiposity-adjusted relative risk estimate for having an increased central adiposity ratio (fourth quartile) compared to lower central adiposity ratios was 1.8 (95% confidence interval, 1.2-2.6). Adjustment for potential confounders of height, parity, and education did not appreciably alter this estimate (1.7, 1.1-2.5). There was no association between degree of adiposity, as measured by the sum of the five skinfolds or by body mass index (weight in kg divided by height in m2), and subsequent breast cancer. The results of this study suggest that increased central to peripheral body fat distribution predicts breast cancer risk independently of the degree of adiposity and may be a more specific marker of a premalignant hormonal pattern than degree of adiposity.