Proportion Of Visceral Adipose Tissue Research Articles

Contribution of epicardial adipose tissue to atrial fibrillation development in patients with arterial hypertension: a pilot study

Aim. To evaluate the value of body mass index (BMI), visceral adipose tissue (VAT) and epicardial adipose tissue (EAT) depots in the development of atrial fibrillation (AF).Material and methods. The study included 24 people with isolated hypertension (HTN) and 28 people with HTN in combination with AF. The median age of patients was 61,5 [53,8;69,0] years. The observational study assessed height, weight, BMI, proportion of VAT, EAT thickness, and cardiac chamber sizes. Height was measured using a metal height meter Rm-1 "Diakoms"; the results were expressed in centimeters. Weight, BMI, and VAT proportion were measured using an Omron BF-508 body composition monitor (Omron, Japan). EAT thickness and cardiac chamber sizes were assessed using two-dimensional echocardiography. Univariate logistic regression models were used to assess the independent contribution of the identified factors associated with the disease presence.Results. Hypertensive patients with and without AF were comparable in terms of BMI and VAT content. At the same time, the EAT content was significantly higher in the group of patients with HTN and AF and amounted to 7,0 [5,0;8,2] mm and 6,0 [4,5;7,0] mm (p=0,027) in the group HTN with and without AF, respectively.Left atrial (LA) volume was 70 [55,2;83,0] ml and 52 [45,5;59,0] ml (p=0,003) in the hypertensive group with and without AF, respectively. Univariate analysis revealed the greatest significance of EAT and LA volume in terms of AF prediction. Logistic regression models did not reveal significant effect of VAT.Conclusion. In hypertensive patients with and without AF at comparable levels of BMI and VAT, differences in EAT thickness and LA volume were identified. Univariate analysis showed that these factors have an advantage in the development of AF. However, even despite the limited sample, the EAT depot was found to be more significant than the VAT depot and BMI in predicting the AF risk.The data that EAT depot and LA volume have the same effect on the arrhythmia risk indicates that patients with AF should be treated not only for hypertension, but also hidden obesity, which we can judge by EAT thickness.

Gestational Weight Gain Is Associated with the Expression of Genes Involved in Inflammation in Maternal Visceral Adipose Tissue and Offspring Anthropometric Measures

Background: Adequate gestational weight gain (GWG) is essential for maternal and fetal health. GWG may be a sign of higher visceral adipose tissue (VAT) accretion. A higher proportion of VAT is associated with an inflammatory process that may play a role in the fetal programming of obesity. This study aimed to (1) compare the expression of genes involved in inflammatory responses (TLR2, TLR4, NFκB, IKKβ, IL-1RA, IL-1β, IL-6, IL-10, TNF-α) in the VAT of pregnant women according to GWG and (2) explore whether VAT inflammation and GWG are related to offspring anthropometric measures. Material and methods: 50 women scheduled for cesarean section who delivered term infants were included in the study. We collected maternal omental VAT, and the expression of genes was examined with RT-qPCR. Results: Women with excessive and with adequate GWG had significantly higher expressions of most inflammatory genes than women with insufficient GWG. Neonates from mothers with excessive GWG had greater birth weight and chest circumference than those from mothers with insufficient GWG. GWG was positively correlated with fetal birth weight. Conclusions: The VAT expression of most genes associated with inflammatory pathways was higher in excessive and adequate GWG than in pregnant women with insufficient GWG. Moreover, GWG was found to be positively associated with newborn weight.

Higher proportion of visceral adipose tissue is associated with smaller regional brain volumes in older adults with type 2 diabetes: Triglycerides may be in the pathway

AbstractBackgroundNumerous studies have identified an increased risk for Alzheimer’s dementia (AD) in Type II Diabetes (T2D). However, the T2D biological characteristics contributing to this risk are still unknown. Adiposity assessed by body mass index (BMI) is one of the main causes of T2D and has been consistently linked to higher dementia risk, faster cognitive decline, and related neural injury. However, the contribution of fat specifically cannot be derived from BMI, which encompasses different adipose tissues, bone, and muscle mass. In this study we examined whether regional abdominal adiposity contributes to AD‐related regional brain volume and mechanism underlying it, in older adults with T2D participating in the Israel Diabetes and Cognitive Decline (IDCD) study.MethodRegional abdominal adiposity was measured so far in 60 participants, including hepatic and pancreatic adiposity and abdominal adipose tissue (AAT), composed of subcutaneous and visceral adipose tissues (SAT and VAT). Brain volumes were assessed for regions associated with cognitive decline (hippocampus, cingulate gyrus, amygdala, and ventromedial prefrontal cortex (vmPFC)). Linear regressions examined associations of regional abdominal adiposity with regional brain volumes adjusting for sociodemographics, BMI and intracranial volume. We also tested if triglycerides, the main components of fat and associated with dementia risk, mediated these associations.ResultGreater VAT:AAT ratio was associated with smaller volumes of the vmPFC (r = ‐0.38; p = 0.026) and hippocampal (r = ‐0.44; p = 0.005) volumes but not with amygdala and cingulate gyrus volumes. The SAT:AAT ratio was associated with greater volumes of the vmPFC (r = 0.40; p = 0.026) and hippocampus (r = 0.48; p = 0.004) but not with amygdala and cingulate. No associations were found between hepatic and pancreatic adiposity with brain volumes. Higher VAT:AAT ratio was associated with higher triglyceride levels (r = 0.38; p = 0.036) which in turn were associated with lower hippocampal volume (r = ‐0.45, p = 0.05). Triglycerides partially mediated the association between VAT:AAT ratio and hippocampal volume (r = ‐0.36; p = 0.03). Triglycerides did not mediate any other associations.ConclusionIn older adults with T2D, a higher proportion of visceral fat may have a detrimental impact on brain regions relevant to cognitive functioning. Higher proportions of subcutaneous fat may have a protective role. Triglycerides, implicated in insulin resistance and chronic systemic inflammation may mediate the VAT‐hippocampus link.

Obesity as an Additional Risk Factor for Thrombogenic Changes in Hemostasis in Hypertensive Patients with Non-Alcoholic Fatty Liver Disease

Introduction: Obesity due to the high proportion of visceral adipose tissue is often leads to hypertension (HT), non-alcoholic fatty liver disease (NAFLD). The risk of thrombogenic complications increases in the presence of NAFLD and HT. Considering the occurrence of prothrombotic changes in the blood in patients with NAFLD, HT and obesity, the combination of these diseases may be an additional risk of thrombosis. Methods: The research was conducted at the Bogomolets National Medical University, at Department Propaedeutics of Internal Medicine No 1. We examined 152 patients and 15 individuals for control group. Results: Mean platelet count was higher in obese patients by 6.4% (p<0.05). In patients with NAFLD without HT, platelet count was higher in the presence of obesity by 16% (p<0.05), we have seen an increase level of MPV in NAFLD patients with obesity. In the comorbid course of HT and NAFLD, aggregation of platelets stimulated by adrenaline was grown in case of obesity (18%; p<0.001) relatively to non-obese patients. In obese patients suffering from HT, these hemostasis changes were characterized by a tendency to accelerate coagulation. There was a reduction in prothrombin time (PT) time by 8.1%, a growth in fibrinogen by 25.8% (p<0.001) and soluble fibrin monomeric complexes (SFMC) by 4 times (p<0.001) in obesity. Conclusion: Obesity increases the thrombogenic activity of blood in both patients with HT and in patients with HT and NAFLD, both due to platelet and coagulation of hemostasis.

Heterogeneity of abdominal obesity in patients with cardiovascular diseases

Aim: To assess the content of visceral adipose tissue (VAT) in patients with abdominal obesity and its relationship with metabolic disorders.Material and methods. Patients with abdominal obesity (n=107) were included in the study. All participants had an assessment of anthropometric parameters (height, weight), calculation of body mass index (BMI), proportion of total adipose tissue and VAT (bioimpedance analyzer), high-density lipoprotein cholesterol (HDL-c) levels, triglycerides, fasting blood glucose, epicardial thickness adipose tissue (two-dimensional echocardiography).Results. The median share of VAT (bioimpedance method) was 13%. Patients with abdominal obesity are divided by VAT into 2 groups: ≥14% or ≤13%. Patients with VAT≥14% had significantly higher levels of triglycerides (1.76 [1.27; 2.38] mmol / L) and glucose (6.33 [5.78; 7.87] mmol / L), and below HDL-c levels (0.95 [0.85; 1.21] mmol / L) compared with patients with VAT≤13% (1.32 [1.02; 1.50], 5.59 [5, 11; 6.16] and 1.31 [1.07; 1.58] mmol / L, respectively; p<0.001 for all three comparisons). A significant correlation was found between VAT and triglyceride, glucose and HDL-c levels (r=0.40; r=0.40; r=-0.31, respectively; p<0.001).Conclusion. Persons with abdominal obesity are heterogeneous in the proportion of VAT. The proportion of VAT above the median is associated with metabolic disorders that are significant for the development and progression of atherosclerosis. An increase in BMI in obese individuals is not associated with an increase in VAT and an increase in the severity of metabolic disorders.

Changes in Visceral Fat and Its Correlation With Changes in Metabolic Variables After Bariatric Surgery

Obesity is a health problem. There is a relationship between visceral adipose tissue (VAT) and various metabolic components. So far the most effective treatment for weight reduction and control of comorbidities is bariatric surgery. After bariatric surgery there is a reduction in VAT and a correlation with better control of metabolic variables would be expected. Objective: To determine the decrease in VAT, calculated by bioimpedance at 3 and 6 months after bariatric surgery and its correlation with changes in metabolic parameters (fasting glucose, HOMA, HbA1c, lipid profile). MATERIAL AND Methods: Patients belonging to the HECMNSXXI Obesity Clinic undergoing bariatric surgery during 2020 who agreed to participate in the study were included. VAT volume was determined before surgery and at 3 and 6 months after the procedure by bioimpedance using the SECA mBCA525 body analyzer. At the same time, biochemical metabolic markers were determined (fasting glucose, HOMA, HbA1c, CT, HDL, LDL, and triglycerides). The results were reported using descriptive statistics. A Pearson or Spearman correlation was carried out according to the distribution of the variables. P <0.05 was taken as significant. Results: Eleven patients with a mean age of 49 ± 7 years were included, 73% of them were women. Their average initial BMI was 42 ± 4 kg/m2. VAT prior to surgery had a mean of 10.6 ± 2.5L for men and 6.4 ± 2.4L for women. Eighty-two percent of the patients fulfilled harmonized criteria for metabolic syndrome. There was a statistically significant decrease in VAT at 3 and 6 months after surgery in both men and women (Baseline 7.5 ± 3L, 3 months 3.8 ± 2.8 L (p <0.001), 6 months 2.5 ± 2 L (p = 0.001). An average decrease in visceral adipose tissue of 57 ± 24% in women and 34 ± 18% in men (p = 0.18) was found 3 months after surgery and 70 ± 22% in women and 60 ± 21% in men (p = 0.53) 6 months after surgery. Laparoscopic one-anastomosis gastric bypass (OAGB) was the type of surgery with the highest percentage of VAT loss at 3 and 6 months, however, this was not statistically significant when compared with Y-Roux Gastric bypass (YRGB). A statistically significant decrease in HbA1c, HOMA, total cholesterol, LDL, and triglycerides levels were found at 3 and 6 months after surgery. However, when correlating the proportion of VAT lost with the metabolic variables, only a significant correlation was found with the HbA1c levels. The higher the proportion of VAT lost, the lower the HbA1c levels (R2 -0.72 p = 0.01). Conclusions: Bariatric surgery produces a statistically significant reduction in visceral adipose tissue from 3 months after surgery. In this study, an inversely proportional correlation was found between the proportion of VAT lost and HbA1c levels.

CT-derived abdominal adiposity: Distributions and better predictive ability than BMI in a nationwide study of 59,429 adults in China

BackgroundAlthough abdominal adiposity is associated with an altered cardiometabolic risk profile, the specific contribution of abdominal adipose tissue distribution remains not fully understood. Computed tomography (CT) is a well-established and precise method to measure abdominal adipose tissue distribution. The present study investigated abdominal adiposity assessed by CT in a large-scale Chinese population. MethodA total of 59,429 adults who underwent a low dose chest CT for lung cancer screening at one of 13 health checkup centers throughout China were evaluated. Abdominal visceral adipose tissue (VAT) and subcutaneous adipose tissue (SAT) areas were measured at the center of the 2nd lumbar vertebra with Mindways quantitative CT software using the existing CT dataset without any additional radiation exposure. The ratio of visceral to total adipose tissue (TAT) areas (VAT/TAT ratio) was calculated and expressed as a percentage. Anthropometric indices including body mass index (BMI) and waist circumference were also obtained. ResultsBMI, waist circumference, VAT area, SAT area, and the VAT/TAT ratio were 25.0 ± 3.0 kg/m2, 90 ± 8 cm, 194 ± 77 cm2, 85 ± 41 cm2, and 69.5 ± 9.1%, respectively, in men and 23.3 ± 3.1 kg/m2, 79 ± 8 cm, 120 ± 57 cm2, 123 ± 53 cm2, and 48.9 ± 9.7% in women. With increasing age, VAT area and the VAT/TAT ratio increased in both sexes whereas SAT area decreased in men (P < 0.001 for all). After adjustment for BMI and waist circumference, older individuals showed higher VAT area and higher VAT/TAT ratio than younger subjects (P < 0.001 for all). Adjusted VAT areas in participants aged 75 or older was 45 cm2 (95% confidence interval [CI]: 41 cm2, 50 cm2) higher in men and 43 cm2 (95% CI: 37 cm2, 49 cm2) higher in women compared with participants aged 31–44 years. Additionally, differences in VAT area across age groups increased as BMI or waist circumference increased. VAT and SAT areas, but not the VAT/TAT ratio, were positively associated with BMI and waist circumference in every age group. ConclusionIn a nationwide study conducted in China, distributions of CT-derived measures of visceral and subcutaneous adiposity were found to vary significantly between sex and age groups. Our study also revealed that the proportion of VAT (an important driver of cardiometabolic risk) could not be predicted from BMI in a Chinese population.

Metabolic role of visceral adipose tissue and main methods of its diagnosis at the present stage

A review of the literature on the metabolic role of visceral adipose tissue and the main methods for its diagnosis is presented. Visceral adipose tissue is an active endocrine organ what secretes a number of biologically active substances. With an increase in the proportion of visceral adipose tissue, moderate inflammation is observed with a chronic systemic increase in the activity of adipokines. Adipokines carry out several immune or metabolic functions associated with inflammatory infiltration. Active substances such as leptin, adiponectin, resistin, etc., the source of which is visceral adipose tissue, have peripheral, central and local effects on the metabolism of glucose and lipids, glycolysis processes in the liver, etc. It is the activity of visceral adipose tissue that should be considered among the main pathophysiological development factors obesity and its potential metabolic cardiovascular and/or liver complications.

Abstract WP422: 18 F-FDG PET/CT Imaging Factors for Prediction of Ischemic Stroke in Cancer Patients

Objective: 18 F-FDG PET/CT can acquire both anatomical and functional images in a single session. We investigated which factors of 18 F-FDG PET/CT imaging have potential as biomarkers for an increased risk of ischemic stroke in cancer patients. Methods: One hundred and thirty-four cancer patients were enrolled. A new infarct lesion in brain MRI within 1 year after FDG PET/CT defined future ischemic stroke. A target-to-background ratio (TBR) for each arterial segment defined arterial inflammation on PET imaging. Abdominal obesity was defined as area and proportion of visceral adipose tissue (VAT), subcutaneous adipose tissue and total adipose tissue (TAT), on a single CT slice at the umbilical level. Results: Thirty patients experienced the occurrence of future ischemic stroke confirmed by MRI. Patients who suffered a stroke had TBRs in carotid arteries and the abdominal aorta ( P &lt;0.001) that were higher than those in patients without stroke. Patients with stroke had higher VAT ( P =0.021) and TAT ( P= 0.041) proportions than patients without stroke. Multiple logistic regression analysis showed that TBRs of the carotid arteries and abdominal aorta, VAT and TAT proportions, and metabolically active tumors were significantly associated with future ischemic stroke. The combination of PET and CT variables improved predictive power for future ischemic stroke. Conclusion: Our findings suggest that arterial FDG uptake and hypermetabolic malignancy on PET, and VAT proportion on CT, could be independent predictors of future ischemic stroke in patients with cancer and identify those patients who would benefit from medical treatment.

Changes in abdominal fat following antiretroviral therapy initiation in HIV-infected individuals correlate with waist circumference and self-reported changes.

We examined whether waist circumference (WC) and self-reported abdominal size changes can estimate visceral adipose tissue (VAT) changes for those initiating antiretroviral therapy (ART). Prospectively collected data from ACTG A5257 and its metabolic substudy, A5260s, were used for this analysis. ART-naive HIV-infected participants were randomized to one of three contemporary ART regimens. Changes in abdominal CT-measured VAT and total adipose tissue (TAT) and DXA-measured trunk fat were tested for association with WC changes (by Pearson correlation) and categories of self-reported abdominal size changes (by ANOVA) between entry and week 96. Linear models compared WC and self-reported changes. The study population (n=328) was predominantly male (90%) and White non-Hispanic (44%) with a baseline median age of 36 years and body mass index of 25 kg/m2. At week 96, median WC change was +2.8 cm. Of those reporting at week 96, 53% indicated 'no change/lost', 39% 'gained some/somewhat larger' and 8% 'gained a lot/much larger' as their self-reported changes. Trunk fat, VAT and TAT changes differed across self-reported groups (ANOVA P<0.0001 for all), and the group ordering was as expected. WC changes were strongly correlated with CT and DXA changes (trunk fat: ρ=0.72, p<0.0001; VAT: ρ=0.52, p<0.0001; TAT: ρ=0.62, p<0.0001). While WC changes explained a greater proportion of VAT, TAT and trunk fat variation, self-reported changes remained a significant predictor after controlling for WC (p<0.05). WC and self-reported abdominal changes each correlated directly with imaging-derived abdominal fat measures, and can be used as reliable, affordable tools for central adiposity assessment.

A prospective evaluation of obesometric parameters associated with renal stone recurrence.

Our aim was to evaluate whether obesometric serum hormones and body fat distribution are associated with renal stone recurrence. We conducted a prospective cohort study of participants undergoing renal stone (RS) intervention at a single institution from November 2009-June 2010 and followed them for a median 62 months. Obesometric parameters were measured at baseline, including body mass index (BMI), fasting serum leptin and adiponectin, and proportion of visceral adipose tissue (%VAT) averaged from three fixed axial computed tomography (CT) slices. The primary study outcome was stone recurrence. A total of 110 participants were enrolled. Elevated %VAT was associated RS recurrence; participants with %VAT in the highest quartile had a five-year stone-free rate of 47.1% compared to 72.2% among other participants (p=0.004). Adjusting for gender, elevated %VAT was independently predictive of renal stone recurrence among initial stone formers (n=74; hazard ratio [HR] 4.53, 95% confidence interval [CI] 1.08-19.02), but not among recurrent stone formers (n=19; HR 0.51, 95% CI 0.054-4.72). Other obesometric factors, including leptin, adiponectin, and BMI, were not significantly predictive of recurrence. We report a novel association between an elevated %VAT and stone recurrence. These findings may inform patient counselling and followup regimens. The metabolic basis for these findings requires further investigation.

18F-FDG PET/CT imaging factors that predict ischaemic stroke in cancer patients.

18F-FDG PET/CT can acquire both anatomical and functional images in a single session. We investigated which factors of 18F-FDG PET/CT imaging have potential as biomarkers for an increased risk of ischaemic stroke in cancer patients. From among cancer patients presenting with various neurological symptoms and hemiparesis, 134 were selected as eligible for this retrospective analysis. A new infarct lesion on brain MRI within 1year of FDG PET/CT defined future ischaemic stroke. The target-to-background ratio (TBR) of each arterial segment was used to define arterial inflammation on PET imaging. Abdominal obesity was defined in terms of the area and proportion of visceral adipose tissue (VAT), subcutaneous adipose tissue and total adipose tissue (TAT) on a single CT slice at the umbilical level. Ischaemic stroke confirmed by MRI occurred in 30 patients. Patients with stroke had higher TBRs in the carotid arteries and abdominal aorta (P < 0.001) and a higher VAT proportion (P = 0.021) and TAT proportion (P = 0.041) than patients without stroke. Multiple logistic regression analysis showed that TBRs of the carotid arteries and abdominal aorta, VAT and TAT proportions, and the presence of a metabolically active tumour were significantly associated with future ischaemic stroke. Combining PET and CT variables improved the power for predicting future ischaemic stroke. Our findings suggest that arterial FDG uptake and hypermetabolic malignancy on PET and the VAT proportion on CT could be independent predictors of future ischaemic stroke in patients with cancer and could identify those patients who would benefit from medical treatment.

Prenatal notch1 receptor blockade by protein delta homolog 1 (DLK1) modulates adipocyte size in vivo.

The protein delta homolog 1 (DLK1) has been reported to have an important role as inhibitor of adipogenesis. Understanding its mode of action can be a promising approach to cope with the formation of obesity. However, data on DLK1 signaling are not consistent, and especially its role as negative regulator of Notch receptors is discussed controversially. DLK1 effects have been investigated in differentiated 3T3-L1 cells by Adipokine Profiler Array, enzyme-linked immunosorbent assay and quantitative real-time PCR (qRT-PCR). In vivo effects of DLK1 on adipogenesis have been studied by the DLK1 treatment of pregnant C57BL/6NTac mice and the phenotypical characterization of the offspring fed on chow or high-fat diet (HFD). Furthermore, gene expression of key adipogenesis genes in adipose tissue (AT) samples was observed by qRT-PCR. In 3T3-L1 cells, DLK1 was found to be an inhibitor of Notch1 signaling. Gene expression of Notch1 and Hes1 was lowered by 53% and 65%, respectively, and the expression of protein target PAI-1 was decreased by 51%. The offspring of DLK1-treated pregnant mice were fed chow or HFD starting from week 4. At week 18, a larger proportion of visceral AT was determined on HFD after DLK1 treatment (P=0.011), whereas adipocyte size was reduced (P=0.007 for maximal size). This was affiliated to an upregulation of adipocyte differentiation. The underlying mechanism was found in an increased expression of the Notch1 receptor gene and protein in AT of the offsprings independently of the diet. However, feeding a chow diet resulted in a decreased expression of Notch1 target genes Hes1 and RBP-Jκ, whereas under HFD these genes were upregulated. Treatment of mice with recombinant human DLK1 during pregnancy has significant effects on AT of the offspring. This can be associated with counter-regulatory changes in the Notch1 signaling cascade.

Anatomical and CT approach of the adipose tissue: application in morbid obesity.

The importance and proportion of visceral adipose tissue (VAT) represent the best criterion to define obesity. Because VAT value is difficult to obtain in clinical practice, the indication for bariatric surgery is still based at present on Body Mass index (BMI), even though BMI is a poor predictor of obesity-related morbid complications. This correlation study aimed at determining a simple and accurate computed tomography (CT) anatomic marker, which can be easily used clinically, well correlated with the volume of VAT and consequently with morbid complications. We studied 108 CT scans of patients presenting with morbid obesity. Several simplified measures (external and internal abdominal diameters and circumferences) were conducted on CT scan view, going through the fourth lumbar vertebra (L4), in addition to various vertebral measurements (area of the vertebra, sagittal and transversal diameters), VAT and subcutaneous adipose tissue (SAT). Then, we reported the simplified measures values on the vertebral areas, and we calculated the Bertin index. Finally, we conducted a correlation study between all variables to obtain accurate VAT measurements. The internal abdominal circumference and the Bertin index showed the best correlations with VAT in morbidly obese patients (r=0.84 and 0.85, respectively). BMI and anthropometric measures were not correlated with VAT. CT scan study allows to simply approximate VAT value in morbidly obese patients. An abdominal CT scan could be part of the tests used in the evaluation of obese patients to base therapeutic strategies on VAT values and not on BMI as it is the case today.

732 VISCERAL OBESITY AND RISK OF HIGH-GRADE DISEASE IN CLINICAL T1A RENAL CELL CARCINOMA

You have accessJournal of UrologyKidney Cancer: Evaluation & Staging (II)1 Apr 2013732 VISCERAL OBESITY AND RISK OF HIGH-GRADE DISEASE IN CLINICAL T1A RENAL CELL CARCINOMA Yao Zhu, Hong-Kai Wang, and Ding-Wei Ye Yao ZhuYao Zhu Shanghai, China, People's Republic of More articles by this author , Hong-Kai WangHong-Kai Wang Shanghai, China, People's Republic of More articles by this author , and Ding-Wei YeDing-Wei Ye Shanghai, China, People's Republic of More articles by this author View All Author Informationhttps://doi.org/10.1016/j.juro.2013.02.295AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookTwitterLinked InEmail INTRODUCTION AND OBJECTIVES Accurate assessment of disease characteristics is a prerequisite for treatment decision making in small renal masses. The aim of the current study was to evaluate the association between visceral obesity and Fuhrman grade (FG) in patients with cT1a renal cell carcinoma (RCC). METHODS We retrospectively collected data on 186 patients with surgically treated cT1a RCC. Single-slice computed tomography images were used to measure the area of visceral and subcutaneous adipose tissue. Visceral obesity was calculated as the proportion of visceral adipose tissue to overall adipose tissue (VAT%). Other analyzed factors included clinical characteristics (age, gender, body mass index and tumor size) and anatomic features of the tumor defined by RENAL nephrometry score. The association between predictors and high-grade disease (FG III or IV) were assessed using logistic regression analyses. RESULTS Fourty-seven (25.3%) tumors were classified as high-grade. VAT% was higher in male participants, but didn't correlate with body mass index, age or tumor size. In univariate analyses, VAT% and tumor size were significantly associated with higher FG. Multivariate analysis showed that VAT% (odds ratio=1.06, p=0.0018) and tumor size (odds ratio=1.91, p=0.047) were independent predictors of high-grade cancer. Addition of VAT% to a model including clinical characteristics and anatomic features of the tumor remarkably improved its discriminatory ability (p=0.0010). CONCLUSIONS Increased visceral obesity was found to be strongly associated with higher FG in patients with cT1a RCC. Further studies are needed to confirm these findings and discover the underlying biological mechanism. © 2013 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 189Issue 4SApril 2013Page: e301 Advertisement Copyright & Permissions© 2013 by American Urological Association Education and Research, Inc.MetricsAuthor Information Yao Zhu Shanghai, China, People's Republic of More articles by this author Hong-Kai Wang Shanghai, China, People's Republic of More articles by this author Ding-Wei Ye Shanghai, China, People's Republic of More articles by this author Expand All Advertisement Advertisement PDF downloadLoading ...

Visceral Obesity and Risk of High Grade Disease in Clinical T1a Renal Cell Carcinoma

Accurate assessment of disease characteristics is a prerequisite for treatment decision making regarding small renal masses. In this study we evaluate the association between visceral obesity and Fuhrman grade in patients with cT1a renal cell carcinoma. We retrospectively collected data on 186 patients with surgically treated cT1a renal cell carcinoma. Single slice computerized tomography was used to measure the area of visceral and subcutaneous adipose tissue. Visceral obesity was calculated as the proportion of visceral adipose tissue to overall adipose tissue. Other analyzed factors included clinical characteristics (age, gender, body mass index and tumor size) and anatomical features of the tumor defined by the R.E.N.A.L. nephrometry score. The association between predictors and high grade disease (Fuhrman grade III or IV) were assessed using logistic regression analyses. A total of 47 (25.3%) tumors were classified as high grade. The percentage of visceral adipose tissue was higher in male participants but did not correlate with body mass index, age or tumor size. In univariate analyses the percentage of visceral adipose tissue and tumor size were significantly associated with higher Fuhrman grade. Multivariate analysis showed that the percentage of visceral adipose tissue (OR 1.06, p = 0.0018) and tumor size (OR 1.91, p = 0.047) were independent predictors of high grade cancer. Addition of the percentage of visceral adipose tissue to a model including clinical characteristics and anatomical features of the tumor remarkably improved its discriminatory ability (p = 0.0010). Increased visceral obesity was found to be strongly associated with higher Fuhrman grade in patients with cT1a renal cell carcinoma. Further studies are needed to confirm these findings and discover the underlying biological mechanism.

Plasma amino acid profile is associated with visceral fat accumulation in obese Japanese subjects.

What is already known about this subject • Asians with metabolic complications associated with obesity, a low body mass index and a low waist circumference have a greater proportion of visceral adipose tissue for a given amount of total body fat compared with Europeans. • Apparent obese humans and obese animal models show an elevation of branched-chain amino acid levels in plasma. • A multivariate logistic regression model of plasma free amino acids has been used to screen for several types of cancers in clinical settings. What this study adds • A specific formula incorporating six amino acid values (Ala, Gly, Glu, Trp, Tyr and branched-chain amino acid) was developed for discrimination of subjects with high visceral fat area by multivariate logistic regression analyses. • The generated amino acid formula was strongly correlated with visceral fat area in both apparent and non-apparent obese subjects. • Measuring plasma free amino acids can be used to distinguish the non-apparent visceral obesity in clinical settings in Asian populations. Metabolic complications associated with obesity are becoming more common among Japanese subjects. However, visceral fat accumulation is not always apparent by measuring body mass index (BMI) or waist circumference in Asian populations because of the physiological characteristics particular to those ethnicities. Excess visceral fat accumulation raises the odds ratio for developing cardiovascular disease. Thus, high-throughput determination of the amount of abdominal adipose tissue is necessary. We hypothesized that accumulating visceral fat alters the peripheral amino acid profile and that a multivariate logistic regression model of plasma free amino acids can distinguish visceral obesity. A total of 1449 Japanese subjects (985 males and 464 females) who had undergone a comprehensive health screening were enrolled in this study. The visceral fat area was determined using computed tomography imaging, and a plasma free amino acid index to identify high visceral fat areas (≥100 cm(2) ) was developed. The sensitivity and specificity values of the generated amino acid index were 80% and 65%, respectively. In particular, the sensitivity of the generated index to identify subjects with non-apparent visceral obesity (BMI < 25 kg m(-2) ; visceral fat area ≥ 100 cm(2) ) was much greater than that of the waist circumference (73% vs. 46%, respectively). This index's high sensitivity and specificity may be the result of specific alterations in the patients' amino acid profiles, which were specifically correlated with the visceral fat areas and not with subcutaneous fat areas. This profile can be used as a predictor of elevated visceral obesity and a risk assessment tool for metabolic complications in Asian populations.

Influence of motor complete spinal cord injury on visceral and subcutaneous adipose tissue measured by multi-axial magnetic resonance imaging

Objective: Abdominal obesity conveys substantial health risks, in association with high levels of visceral adipose tissue (VAT), subcutaneous adipose tissue (SAT) and an increased proportion of VAT to SAT. The purposes were to determine the influence of spinal cord injury (SCI) on the associations between single axial cross-sectional area (CSA) slices and the average CSA or volumes of VAT and SAT across multi-axial slices of magnetic resonance imaging (MRI); and the relationships relative to the whole body composition and anthropometrics.Methods: Thirteen healthy male participants with traumatic motor complete SCI underwent fast spin-echo MRI to measure VAT and SAT across multi-axial slices, followed by dual-energy X-ray absorptiometry to measure whole body fat-free mass (FFM) and fat mass (FM). Waist circumference (WC) was also measured in the seated position.Results: The trunk CSAs of VAT and SAT were 99 ± 51 and 164 ± 69 cm2, respectively, and the ratio of VAT to SAT was 0.68 ± 0.33. The CSAs of VAT and SAT at a single slice strongly predicted the average CSA and modestly predicted the volumes across multi-axial slices. VAT and SAT represented 5.7 ± 1.8% and 9.7 ± 3.2% of the total body FM, respectively. Percent body FFM was negatively related to VAT and SAT volumes, but not to a single axial CSA.Conclusion: A single slice CSA can modestly predict the volume of multi-axial slices in individuals with SCI, yet it is not related to any of the body composition variables. Increased percent FFM is associated with a reduction in VAT and SAT volumes measured across multi-axial slices. The ratio of VAT to SAT is greater than 0.4, suggesting that individuals with SCI are at high risk of developing metabolic sequelae.

Distribution of abdominal adipose tissue as a predictor of hepatic steatosis assessed by MRI

To evaluate the relationship between the distribution of visceral and subcutaneous adipose tissue and hepatic steatosis assessed using magnetic resonance imaging (MRI). One T1-weighted, in-/out-of-phase, single-section sequence at the L3/L4 level and one multi-echo gradient MRI (MGRE) sequence were performed on 65 patients [19 females and 46 males; age 57+/-9.5 years; body mass index (BMI) 31+/-5.1kg/m(2)]. Visceral adipose tissue (VAT), subcutaneous adipose tissue (SAT) surfaces, and hepatic steatosis were automatically calculated using in-house software. Weight, height, BMI, waist circumference, hip circumference, and waist:hip ratio were recorded. The probability of having a steatosis greater than 10% on MRI was evaluated by receiver operating characteristic (ROC) curves. The anthropometric parameter best correlated to hepatic steatosis was the waist-to-hip ratio (r=0.301). VAT and proportion of VAT were correlated to liver fat content (r=0.307 and r=0.249, respectively). No significant correlations were found for BMI, hip circumference, and SAT. The area under the receiver operating characteristics (AUROCs) for the relationship between liver steatosis and BMI, waist circumference, waist:hip ratio, VAT surface, and proportion of VAT, were respectively 0.52, 0.63, 0.71, 0.73 and 0.75. Adipose tissue distribution is more relevant than total fat mass when assessing the possibility of liver steatosis in overweight patients.

The impact of liposuction on body fat.

Routine liposuction has very low perioperative complication rates and is thus considered to be innocuous. Some authors have even proposed that large-volume liposuction could be therapeutic. However, because subcutaneous adipose tissue has nutritional and thermodynamic metabolic functions proportional to the absolute amount and the distribution of fat, it is possible that removal of subcutaneous adipose tissue might be detrimental. We measured the amount of fat removed by large-volume (>1000 cc) liposuction and expressed the results in terms of absolute and relative changes in total body fat and in visceral adipose tissue (nonsubcutaneous adipose tissue) in 63 normal weight to mildly obese women (n = 51) and men (n = 12). Aspiration of 1.5 +/- 0.7 kg (mean +/- SD) of lipid in women removed 9.2 +/- 3.2 percent of body fat or 10.5 percent of subcutaneous adipose tissue corresponding to a 12-percent increase in the ratio of visceral to subcutaneous adipose tissue. One third of the women (n = 17) had a mean increase of 16 percent (range 13 to 21 percent) in the proportion of visceral fat. In the 12 men, aspiration of 1.7 +/- 0.6 kg of lipid removed 9.8 +/- 2.9 percent of body fat or 12.7 +/- 3.6 percent of subcutaneous adipose tissue, resulting in a 14-percent increase in the ratio of visceral to subcutaneous fat. The correlation between aspirate and body mass index was 0.57 (p < 0.001). Although large-volume subcutaneous liposuction removed relatively little body fat, it led to significant increases in the proportion of visceral adipose tissue. Because the proportion of visceral adipose tissue is a risk factor for metabolic complications of obesity, the metabolic effects of large-volume liposuction need to be evaluated.