Visceral Adipose Tissue Volume Research Articles

The causal relationship between air pollution, obesity, and COVID-19 risk: a large-scale genetic correlation study.

Observational evidence reported that air pollution is a significant risk element for numerous health problems, such as obesity and coronavirus disease 2019 (COVID-19), but their causal relationship is currently unknown. Our objective was to probe the causal relationship between air pollution, obesity, and COVID-19 and to explore whether obesity mediates this association. We obtained instrumental variables strongly correlated to air pollutants [PM2.5, nitrogen dioxide (NO2) and nitrogen oxides (NOx)], 9 obesity-related traits (abdominal subcutaneous adipose tissue volume, waist-to-hip ratio, body mass index, hip circumference, waist circumference, obesity class 1-3, visceral adipose tissue volume), and COVID-19 phenotypes (susceptibility, hospitalization, severity) from public genome-wide association studies. We used clinical and genetic data from different public biological databases and performed analysis by two-sample and two-step Mendelian randomization. PM2.5 genetically correlated with 5 obesity-related traits, which obesity class 1 was most affected (beta = 0.38, 95% CI = 0.11 - 0.65, p = 6.31E-3). NO2 genetically correlated with 3 obesity-related traits, which obesity class 1 was also most affected (beta = 0.33, 95% CI = 0.055 - 0.61, p = 1.90E-2). NOx genetically correlated with 7 obesity-related traits, which obesity class 3 was most affected (beta = 1.16, 95% CI = 0.42-1.90, p = 2.10E-3). Almost all the obesity-related traits genetically increased the risks for COVID-19 phenotypes. Among them, body mass index, waist circumference, hip circumference, waist-to-hip ratio, and obesity class 1 and 2 mediated the effects of air pollutants on COVID-19 risks (p < 0.05). However, no direct causal relationship was observed between air pollution and COVID-19. Our study suggested that exposure to heavy air pollutants causally increased risks for obesity. Besides, obesity causally increased the risks for COVID-19 phenotypes. Attention needs to be paid to weight status for the population who suffer from heavy air pollution, as they are more likely to be susceptible and vulnerable to COVID-19.

SAT445 Exposure To Perfluoroalkyl Substances At Preconception In Association With Metabolic Phenotype In Women From Singapore

Abstract Disclosure: N.J. Cohen: None. M. Yao: None. V. Midya: None. S. India-Aldana: None. S.S. Andra: None. S. Narasimhan: None. A.K. Meher: None. M. Arora: None. J.K. Chan: None. S.Y. Chan: None. Y. Kway: None. N. Michael: None. S.A. Sadanathan: None. J.G. Eriksson: None. S.S. Velan: None. T.K. Hian: None. Y. Oulhote: None. J. Huang: None. D. Valvi: None. Background and Aim: Exposure to perfluoroalkyl substances (PFAS) may result in adverse metabolic health outcomes, but few studies have focused on preconception PFAS exposures and metabolic dysregulation which could impact pregnancy. We assessed cross-sectional and prospective associations between preconception PFAS concentrations and glucose regulation, insulin sensitivity, and magnetic resonance imaging (MRI) based adiposity measures in a Singaporean cohort of women who were actively attempting to conceive. Methods: Our analyses included 384 participants from the Singapore Preconception Study of Long-Term Maternal and Child Outcomes (S-PRESTO), from which 126 underwent abdominal MRI at preconception. 15 different PFAS in preconception plasma samples were measured, and metabolic measures were cross-sectionally assessed at preconception (waist-to-height ratio [WHtR], 2-hour oral glucose tolerance test [OGTT] indices, and MRI-based measures of abdominal adiposity and liver fat), and prospectively at 24-28 weeks of gestation (2-hour OGTT indices). We used linear regression models to assess associations between individual PFAS and metabolic phenotype at preconception and pregnancy. In addition, we used Bayesian weighted quantile sum (BWQS) regression to assess the joint associations of the PFAS mixture with study outcomes. Results: We observed negative associations between perfluorononanoic acid (PFNA) concentrations and visceral adipose tissue (VAT; log2-transformed) volume (β per doubling of PFNA=-0.12 cm3, 95% CI -0.24, 0.00) and log2-transformed liver fat percentage (β=-0.28%, 95% CI -0.52, -0.04). Inverse associations were observed between the individual PFAS and most mid-pregnancy OGTT indices and insulin resistance, but were not statistically significant. Associations were not statistically significant for all preconception OGTT indices. Conclusions: We did not find strong evidence for an association between preconception PFAS concentrations and prenatal metabolic outcomes in young women in Singapore. Cross-sectional analyses indicated reduced adiposity in VAT volume and liver fat percentage with increasing PFAS concentration, which requires further investigation in prospective, more diverse, and larger studies. Presentation: Saturday, June 17, 2023

Resistance training decreased abdominal adiposity in postmenopausal women.

To investigate if abdominal adipose tissue volumes and ratios change after a 15-week structured resistance training intervention in postmenopausal women with vasomotor symptoms (VMS). Sixty-five postmenopausal women with VMS and low physical activity were randomized to either three days/week supervised resistance training or unchanged physical activity for 15weeks. Women underwent clinical anthropometric measurements and magnetic resonance imaging (MRI) at baseline and after 15weeks. MRI was done using a Philips Ingenia 3.0T MR scanner (Philips, Best, The Netherlands). The per protocol principle was used in the analysis of data. The absolute change from baseline to week 15 in visceral adipose tissue (VAT) volume and the relative ratio (VAT ratio) between VAT and total abdominal adipose tissue (TAAT), i.e. the sum of abdominal subcutaneous adipose tissue (ASAT) and VAT. There were no significant differences between the groups in characteristics, anthropometry or MRI measures at baseline. Women who were compliant with the intervention (i.e. participated in at least two of the three scheduled training sessions per week) had significantly different reduction over time in ASAT (p=0.006), VAT (p=0.002), TAAT (p=0.003) and fat ratio (p<0.001) compared with women in the control group. Implementation of a 15-week resistance training regimen in midlife may help women to counteract the abdominal fat redistribution associated with the menopausal transition. gov registered ID: NCT01987778.

Optimal computed tomography-based biomarkers for prediction of incisional hernia formation.

Unstructured data are an untapped source for surgical prediction. Modern image analysis and machine learning (ML) can harness unstructured data in medical imaging. Incisional hernia (IH) is a pervasive surgical disease, well-suited for prediction using image analysis. Our objective was to identify optimal biomarkers (OBMs) from preoperative abdominopelvic computed tomography (CT) imaging which are most predictive of IH development. Two hundred and twelve rigorously matched colorectal surgery patients at our institution were included. Preoperative abdominopelvic CT scans were segmented to derive linear, volumetric, intensity-based, and textural features. These features were analyzed to find a small subset of OBMs, which are maximally predictive of IH. Three ML classifiers (Ensemble Boosting, Random Forest, SVM) trained on these OBMs were used for prediction of IH. Altogether, 279 features were extracted from each CT scan. The most predictive OBMs found were: (1) abdominopelvic visceral adipose tissue (VAT) volume, normalized for height; (2) abdominopelvic skeletal muscle tissue volume, normalized for height; and (3) pelvic VAT volume to pelvic outer aspect of body wall skeletal musculature (OAM) volume ratio. Among ML prediction models, Ensemble Boosting produced the best performance with an AUC of 0.85, accuracy of 0.83, sensitivity of 0.86, and specificity of 0.81. These OBMs suggest increased intra-abdominopelvic volume/pressure as the salient pathophysiologic driver and likely mechanism for IH formation. ML models using these OBMs are highly predictive for IH development. The next generation of surgical prediction will maximize the utility of unstructured data using advanced image analysis and ML.

Hemodynamic Determinants of Elevated Blood Pressure and Hypertension in the Middle to Older-Age UK Population: A UK Biobank Imaging Study.

Increased systemic vascular resistance and, in older people, reduced aortic distensibility, are thought to be the hemodynamic determinants of primary hypertension but cardiac output could also be important. We examined the hemodynamics of elevated blood pressure and hypertension in the middle to older-aged UK population participating in the UK Biobank imaging studies. Cardiac output, systemic vascular resistance, and aortic distensibility were measured from cardiac magnetic resonance imaging in 31 112 (distensibility in 21 178) participants (46.3% male, mean age±SD 63±7 years). Body composition including visceral adipose tissue volume and abdominal subcutaneous adipose tissue volume were measured in 19 645 participants. Participants with higher blood pressure had higher cardiac output (higher by 17.9±26.6% in hypertensive compared with those with optimal blood pressure) and higher systemic vascular resistance (higher by 11.4±27.9% in hypertensive compared with those with optimal blood pressure). These differences were little changed after adjustment for body size and adiposity. The contribution of cardiac output relative to systemic vascular resistance was more marked in younger compared with older subjects. Aortic distensibility decreased with age and was lower in participants with higher compared with lower blood pressure but with a greater difference in younger compared with older subjects. In the middle to older-aged UK population, cardiac output plays an important role in contributing to elevated mean arterial blood pressure, particularly in younger compared with older subjects. Reduced aortic distensibility contributes to a rise in pulse pressure and systolic blood pressure at all ages.

Left atrial strain and ventricular global longitudinal strain in cirrhotic patients using the new criteria of Cirrhotic Cardiomyopathy Consortium.

The new criteria of Cirrhotic Cardiomyopathy Consortium (CCC) propose the use of left ventricular global longitudinal strain (LV-GLS) for evaluation of systolic function in patients with cirrhosis. The aim of this study was to evaluate LV-GLS and left atrial (LA) strain in association with the severity of liver disease and to assess the characteristics of cirrhotic cardiomyopathy (CCM). One hundred and thirty-five cirrhotic patients were included. Standard echocardiography and speckle tracking echocardiography (2D-STE) were performed, and dual X-ray absorptiometry was used to quantify the total and regional fat mass. CCM was defined, based on the criteria of CCC, as having advanced diastolic dysfunction, left ventricular ejection fraction ≤50% and/or a GLS <18%. LV-GLS lower or higher than the absolute mean value (22.7%) was not associated with mortality (logrank, p = 0.96). LV-GLS was higher in patients with Model for end stage liver disease (MELD) score ≥15 compared to MELD score <15 (p = 0.004). MELD score was the only factor independently associated with systolic function (LV-GLS <22.7% vs. ≥22.7%) (Odds Ratio:1.141, p = 0.032). Patients with CCM (n = 11) had higher values of estimated volume of visceral adipose tissue compared with patients without CCM (median: 735 vs. 641 cm3 , p = 0.039). On multivariable Cox regression analysis, MELD score [Hazard Ratio (HR):1.26, p < 0.001] and LA reservoir strain (HR:0.96, p = 0.017) were the only factors independently associated with the outcome. In our study, absolute LV-GLS was higher in more severe liver disease, and LA reservoir strain was significantly associated with the outcome in patients with end-stage liver disease.

Adiposity and Coagulation: Predicting Postinjury Coagulation With Advanced Imaging Analysis

IntroductionAnatomic distribution of adipose tissue has demonstrated variable associations with hypercoagulability. Utilizing a retrospective analysis of a previously enrolled prospective cohort, we assessed computed tomography (CT) scan-based anthropometric and volumetric measures of adiposity as predictors of postinjury hypercoagulability. MethodsSegmentation analysis of arrival CT scans in significantly injured patients at a single level-I trauma center enrolled from December 2017 to August 2021 were analyzed for anthropometric indices of waist circumference (WC) and sagittal abdominal diameter (SAD), and volumetric parameters of visceral adipose tissue, superficial/deep subcutaneous adipose tissue, psoas/paravertebral muscle volume, and abdominal wall muscle volume. Associations with thromboelastography (TEG) were explored. ResultsData from 91 patients showed strong correlations between body mass index and standard anthropometric measures of WC and SAD (P < 0.001); calculated volumes of subcutaneous adipose tissue and visceral adipose tissue (P < 0.001); and ratios of subcutaneous adipose:psoas muscle (SP ratio) and visceral adipose:psoas muscle ratio (both with P < 0.001, respectively). Correlation between TEG maximal amplitude (MA) and body mass index and SAD were not significant, with only weak correlation between TEG-MA and WC (r = 0.238, P = 0.041). Moderate but significant correlations existed between SP ratio and TEG-MA (r = 0.340, P = 0.005), but not visceral adipose:psoas muscle ratio (r = 0.159, P = 0.198). The relationship between TEG-MA and SP ratio remained significant when adjusted for injury severity score and lactate level (b = 0.302, P = 0.001). ConclusionsSP ratio is more strongly correlated with TEG-MA than standard obesity measures, and independently predicts increasing clot strength/stability after injury. Coagulation-relevant measures of sarcopenic obesity can be measured on CT scan, and may be used to optimize thromboprophylaxis strategies for obese injured patients.

Long-term aspartame and saccharin intakes are related to greater volumes of visceral, intermuscular, and subcutaneous adipose tissue: the CARDIA study

BackgroundArtificial sweetener (ArtSw) intakes have been previously associated with higher BMI in observational studies and may promote visceral and skeletal muscle adipose tissue (AT) accumulation. This study aimed to determine whether habitual, long-term ArtSw or diet beverage intakes are related to greater AT depot volumes and anthropometry-related outcomes.MethodsA validated diet history questionnaire was administered at baseline, year 7, and year 20 examinations in 3088 men and women enrolled in the Coronary Artery Risk Development in Young Adults cohort (CARDIA), mean age of 25.2 years and mean BMI of 24.5 kg/m2 at baseline. Volumes of visceral (VAT), intermuscular (IMAT), and subcutaneous adipose tissue (SAT) were assessed by computed tomography at year 25. Linear regression evaluated associations of aspartame, saccharin, sucralose, total ArtSw, and diet beverage intakes with AT volumes, anthropometric measures, and 25-year change in anthropometry. Cox regression estimated associations of ArtSw with obesity incidence. Adjustments were made for demographic and lifestyle factors, total energy intake, and the 2015 healthy eating index.ResultsTotal ArtSw, aspartame, saccharin, and diet beverage intakes were positively associated with VAT, SAT, and IMAT volumes (all ptrend ≤ 0.001), but no associations were observed for sucralose intake (all ptrend > 0.05). In addition, total ArtSw, saccharin, aspartame, and diet beverage intakes were associated with greater body mass index, body weight, waist circumference, and their increases over a 25-year period. Except for saccharin (ptrend = 0.13), ArtSw, including diet soda, was associated with greater risks of incident obesity over a median 17.5-year follow-up (all ptrend < 0.05).ConclusionsResults suggest that long-term intakes of aspartame, saccharin, or diet soda may increase AT deposition and risk of incident obesity independent of diet quality or caloric intake. Coupled with previous evidence, alternatives to national recommendations to replace added sugar with ArtSw should be considered since both may have health consequences.

Towards visceral fat estimation at population scale: correlation of visceral adipose tissue assessment using three-dimensional cross-sectional imaging with BIA, DXA, and single-slice CT.

In terms of assessing obesity-associated risk, quantification of visceral adipose tissue (VAT) has become increasingly important in risk assessment for cardiovascular and metabolic diseases. However, differences exist in the accuracy of various modalities, with a lack of up-to-date comparison with three-dimensional whole volume assessment. Using CT or MRI three-dimensional whole volume VAT as a reference, we evaluated the correlation of various commonly used modalities and techniques namely body impedance analysis (BIA), dual-energy x-ray absorptiometry (DXA) as well as single slice CT to establish how these methods compare. We designed the study in two parts. First, we performed an intra-individual comparison of the 4558 participants from the UK Biobank cohorts with matching data of MRI abdominal body composition, DXA with VAT estimation, and BIA. Second, we evaluated 174 CT scans from the publicly available dataset to assess the correlation of the commonly used single-slice technique compared to three-dimensional VAT volume. Across the UK Biobank cohort, the DXA-derived VAT measurement correlated better (R2 0.94, p<0.0001) than BIA (R2 0.49, p<0.0001) with reference three-dimensional volume on MRI. However, DXA-derived VAT correlation was worse for participants with a BMI of < 20 (R2 = 0.62, p=0.0013). A commonly used single slice method on CT demonstrated a modest correlation (R2 between 0.51 - 0.64), with best values at L3- and L4 (R2 L3 = 0.63, p<0.0001; L4 = 0.64, p<0.0001) compared to reference three-dimensional volume. Combining multiple slices yielded a better correlation, with a strong correlation when L2-L3 levels were combined (R2 = 0.92, p<0.0001). When deployed at scale, DXA-derived VAT volume measurement shows excellent correlation with three-dimensional volume on MRI based on the UK Biobank cohort. Whereas a single slice CT technique demonstrated moderate correlation with three-dimensional volume on CT, with a stronger correlation achieved when multiple levels were combined.

31-OR: Sex-Specific Differences in Subcutaneous Adipose Tissue in Persons with HIV May Contribute to Diabetes Risk

Background: Men with HIV have greater visceral adipose tissue (VAT) accumulation compared to women, which contributes to insulin resistance and derives, in part, from a failure to sequester lipids in subcutaneous adipose tissue (SAT). We assessed whether sex-specific differences in SAT composition are associated with measures of VAT volume and insulin resistance. Methods: Adults with HIV and consistent viral suppression on antiretroviral therapy had SAT and VAT measured by CT imaging, HOMA2-IR using fasting plasma glucose and insulin, and a subset had abdominal SAT lipoaspirates for single-cell RNA-sequencing to define proportions of CD4 and CD8 T effector memory cells (TEM), perivascular (PVM) and intermediate (IM) macrophages, and fibroblasts. Adjusted ordinal regression models and partial Spearman’s assessed the interaction between sex and cell proportions. Results: We enrolled 111 participants (24% female) with a median age of 48 years, BMI of 31.5 kg/m2, and HOMA2-IR of 3.0. VAT volume was significantly associated with HOMA2-IR. Women had lower VAT volumes and higher proportions of SAT PVMs and lower IMs, as well as fewer cytotoxic CD4 and CD8 T cells compared with men (p ≤ 0.05 for all). The proportions of SAT CD4 TEM, CD8 TEM, myofibroblasts, MYOC fibroblasts, and IMs were associated with VAT volume (p ≤ 0.05 for all), but an interaction by sex was not observed. The proportions of CD4 and CD8 TEM cells were significantly associated with HOMA2-IR and there was evidence of an interaction by sex status (interaction term p = 0.09 &amp; p = 0.06, respectively). Conclusions: Women with HIV have a greater adjusted proportion of PVMs and lower cytotoxic CD4 and CD8 T cells in SAT. While the relationship between immune cell proportions and HOMA-IR only appeared to differ for CD4 and CD8 TEM cells, lower ectopic fat deposition in the context of reduced SAT inflammatory cells in women suggests the sex difference in diabetes risk among persons with HIV may relate to adipose tissue cellular composition. Disclosure S.Bailin: None. M.Mashayekhi: None. C.L.Gabriel: None. L.Hannah: None. S.Kalams: None. S.A.Mallal: None. J.A.Kropski: Advisory Panel; APIE Therapeutics, Research Support; Boehringer Ingelheim Inc., Bristol-Myers Squibb Company, Genentech, Inc. C.N.Wanjalla: None. J.Koethe: Advisory Panel; Merck Sharp &amp; Dohme Corp., Janssen Pharmaceuticals, Inc., Gilead Sciences, Inc., Theratechnologies, Research Support; Merck Sharp &amp; Dohme Corp. Funding National Institutes of Health (R01DK112262, UL1RR024975, T32AI007474, P30AI110527)

758-P: Changes in Liver and Abdominal Fat in Tirzepatide-Treated Patients Achieving Normoglycemia in the SURPASS-3 MRI Substudy

Tirzepatide (TZP), a novel, once-weekly GIP/GLP-1 receptor agonist, significantly reduced liver fat content (LFC) and volumes of visceral and abdominal subcutaneous adipose tissue (VAT and ASAT) vs insulin degludec in a subpopulation of patients in the SURPASS-3 phase 3 trial. This post-hoc analysis evaluated changes from baseline to Week 52 in these outcomes and other clinical and laboratory parameters in TZP-treated patients achieving or not achieving normoglycemia (HbA1c &amp;lt;5.7%) at Week 52. LFC, VAT and ASAT volumes were assessed with MRI prior to randomization and at Week 52 in insulin-naïve patients with type 2 diabetes inadequately controlled on metformin with/without SGLT-2i and fatty liver index ≥60 at baseline. Analyses used pooled data from all TZP arms (5, 10, and 15 mg). Patients achieving HbA1c &amp;lt;5.7% were slightly younger and had lower baseline HbA1c and VAT vs those not achieving HbA1c &amp;lt;5.7%. Substantial reductions in LFC, VAT and ASAT volumes, weight, HbA1c, and overall improvement in lipids profile were observed in both subsets of patients (Table). Among patients achieving HbA1c &amp;lt;5.7% and ≥5.7%, respectively, 56% and 27% achieved LFC &amp;lt;6%, and 91% and 64% achieved ≥30% reduction in LFC. In summary, in TZP-treated patients, changes in LFC, VAT and ASAT, and lipids were more pronounced in those achieving normoglycemia. Disclosure Á.Rodríguez: Employee; Eli Lilly and Company, Stock/Shareholder; Eli Lilly and Company. K.Cusi: Consultant; Poxel SA, Altimmune, Arrowhead Pharmaceuticals, Inc., AstraZeneca, 89bio, Inc., Bristol-Myers Squibb Company, Lilly, Madrigal Pharmaceuticals, Inc., Merck &amp; Co., Inc., Medscape, Myovant, Novo Nordisk, ProSciento, Quest Diagnostics, Sagimet, Sonic Incytes, Terns, Research Support; Echosens, Inventiva, LabCorp, Zydus. A.Gastaldelli: Advisory Panel; Pfizer Inc., Novo Nordisk, Merck Sharp &amp; Dohme Corp., Boehringer Ingelheim International GmbH, Consultant; Boehringer Ingelheim International GmbH, Eli Lilly and Company, Fractyl Health, Inc., Merck Sharp &amp; Dohme Corp., Other Relationship; Pfizer Inc., Speaker's Bureau; Eli Lilly and Company. C.Nicolay: Employee; Eli Lilly and Company. A.Torcello-gomez: Employee; Eli Lilly and Company, Stock/Shareholder; Eli Lilly and Company. L.Fernandez lando: Employee; Eli Lilly and Company, Stock/Shareholder; Eli Lilly and Company. Funding Eli Lilly and Company

Metformin versus insulin for gestational diabetes: Adiposity variables and adipocytokines in offspring at age of 9 years

AimsTo compare body composition, visceral adiposity, adipocytokines, and low-grade inflammation markers in prepubertal offspring of mothers who were treated with metformin or insulin for gestational diabetes mellitus (GDM). Methods172 offspring of 311 mothers randomized to receive metformin (n = 82) or insulin (n = 90) for GDMwere studied at 9 years of age (follow-up rate 55%). Measurements included anthropometrics, adipocytokines, markers of the low-grade inflammation, abdominal magnetic resonance imaging (MRI), magnetic liver spectrometry (MRS), and whole body dual-energy X-ray absorptiometry (DXA). ResultsSerum markers of low-grade inflammation, visceral adipose tissue volume, total fat percentage, and liver fat percentage were similar between the study groups. Serum adiponectin concentration was higher in children in the metformin group compared to insulin group (median 10.37 vs 9.50 µg/ml, p = 0.016). This difference between groups was observed in boys only (median 12.13 vs 7.50 µg/ml, p < 0.001). Leptin/adiponectin-ratio was lower in boys in the metformin group than in the insulin group (median 0.30 vs 0.75; p = 0.016). ConclusionsMaternal metformin treatment for GDM had no effects on adiposity, body composition, liver fat, or inflammation markers in prepubertal offspring compared to maternal insulin treatment but was associated with higher adiponectin concentration and lower leptin/adiponectin-ratio in boys.

Associations of insulin-like growth factor binding protein-2 with metabolic profile and hepatic fat deposition in asymptomatic men and women.

Low circulating levels of insulin-like growth-factor binding protein-2 (IGFBP-2) have been associated with increased adiposity and metabolic alterations such as insulin resistance, dyslipidemia, and nonalcoholic fatty liver disease in individuals with obesity. However, whether IGFBP-2 affects energy metabolism in the early stages of these disorders remains unclear. Herein, we hypothesized that plasma IGFBP-2 concentrations are inversely associated with early liver fat accumulation and alterations in lipid and glucose homeostasis in apparently healthy and asymptomatic men and women. Three hundred thirty-three middle-aged Caucasian men and women apparently healthy and without cardiovascular symptoms were enrolled for a cross-sectional cardiometabolic imaging study. Individuals with BMI ≥ 40 kg/m2, cardiovascular disease, dyslipidemia, hypertension, and diabetes were excluded. Fasting glucose and lipid profiles were measured and an oral glucose tolerance test was performed. Liver fat content was assessed by magnetic resonance spectroscopy. Volume of visceral adipose tissue (VAT) was evaluated by magnetic resonance imaging. Plasma IGFBP-2 levels were quantified by ELISA. Participants with low IGFBP-2 levels were characterized by a higher body fat mass (P < 0.0001), insulin resistance (P < 0.0001), higher plasma triglyceride (TG) (P < 0.0001), and lower HDL-cholesterol levels (P < 0.0001) in a sex-independent manner. IGFBP-2 levels were inversely correlated with hepatic fat fraction in both men (r = -0.36, P < 0.0001) and women (r = -0.40, P < 0.0001). IGFBP-2 concentrations were negatively associated with hepatic fat fraction independently of age and VAT in both men (R2 = 0.23, P = 0.012) and women (R2 = 0.27, P = 0.028). In conclusion, our findings show that even in asymptomatic, apparently healthy individuals, low IGFBP-2 levels are associated with a more deteriorated cardiometabolic risk profile and with a high hepatic fat content in a VAT-independent manner. However, IGFBP-2 does not appear to influence the established sexual dimorphism observed for metabolic variables and hepatic fat fraction. Additional studies are required to better understand the relationships between IGFBP-2 and liver fat content.NEW & NOTEWORTHY Faced with a paucity of reliable clinical etiologic markers for fatty liver, this research article demonstrates, for the first time, that low blood levels of the protein IGFBP-2 are associated with a more deteriorated cardiometabolic risk profile and with a high hepatic fat content independently of visceral fat volume and sex, even in asymptomatic, apparently healthy individuals.

The impact of excessive epicardial adipose tissue accumulation on cardiorespiratory fitness in adults without cardiac disease: a cross-sectional magnetic resonance imaging study

Abstract Funding Acknowledgements Type of funding sources: Public grant(s) – National budget only. Main funding source(s): Canadian Institutes of Health Research. Background/Introduction Excessive epicardial adipose tissue (EAT) is associated with worse exercise capacity and is thought to play a role in the pathophysiology of heart failure with preserved ejection fraction. Few studies have explored the relationship between EAT, cardiorespiratory fitness in men and women without cardiovascular disease. Purpose To investigate the association between EAT, cardiorespiratory fitness, and physical activity levels in asymptomatic men and women of variable degree of adiposity. Methods A total of 239 participants (43% women) free from cardiovascular disease who underwent concurrent quantification of EAT volume assessed by cardiac magnetic resonance and a cardiopulmonary exercise testing (CPET) (VO2peak [ml/kg/min]) were studied. Physical activity levels/intensity were measured by questionnaire and using pedometer. Participants were categorized into low-EAT, moderate-EAT, and high-EAT groups on the basis of EAT volume. Results Mean age of participants was 49.8 ± 8.3 years, BMI 26.0 ± 3.7 kg/m2 (15% with obesity), waist circumference 89 ± 11 cm, visceral adipose tissue volume 91.3 ± 51.3 cm3, and EAT volume 9.8 ± 3.1 cm3. EAT volume decreased with increment in cardiorespiratory fitness in men and women of variable adiposity (p&amp;lt;0.05). Men and women with high-EAT had worse cardiometabolic profile (visceral adiposity, insulin resistance, high blood pressure, dysglycemia, atherogenic dyslipidemia), and lower cardiorespiratory fitness (VO2peak) than those with low-EAT (all p&amp;lt;0.05). Physical activity levels were comparable across EAT tertiles (p=NS). The association between EAT and cardiorespiratory fitness was no longer significant after controlling for visceral adiposity. Conclusions In men and women of variable degree of adiposity, excessive EAT accumulation is associated with visceral adiposity and worse cardiorespiratory fitness. Further longitudinal studies are needed to understand the interplay between EAT and cardiorespiratory fitness, and the development of obesity-related heart failure features.

Preliminary observations on the administration of a glucagon-like peptide-1 receptor agonist on body weight and select carbohydrate endpoints in persons with spinal cord injury: A controlled case series

Context/Objective To describe the effect of semaglutide, a glucagon-like peptide-1 (GLP-1) agonist, to reduce body weight and improve glycemic control in overweight or obese individuals with spinal cord injury (SCI). Design Open-label, randomized drug intervention case series. Setting This study was performed at James J. Peters VA Medical Center (JJP VAMC) and Kessler Institute for Rehabilitation (KIR). Participants Five individuals with chronic SCI meeting criteria for obesity and abnormal carbohydrate metabolism. Intervention Administration of semaglutide (subcutaneously once per week) versus no treatment (control) for 26 weeks. Outcome Measures Change in total body weight (TBW), fat tissue mass (FTM), total body fat percent (TBF%), and visceral adipose tissue volume (VATvol) was determined at baseline and after 26 weeks using Dual energy X-ray absorptiometry; fasting plasma glucose (FPG) concentration and serum glycated hemoglobin (HbA1C) values were obtained at the same two time points. Results In 3 participants, after 26 weeks of semaglutide administration, TBW, FTM, TBF%, and VATvol decreased, on average, by 6, 4.4 kg, 1.7%, and 674 cm3, respectively. In addition, values for FPG and HbA1c decreased by 17 mg/dl and 0.2%, respectively. After 26 weeks of observation in the 2 control participants, TBW, FTM, TBF% and VATvol increased on average by 3.3 , 4.5 kg, 2.5%, and 991 cm3, respectively. The average values for FPG and HbA1c also increased by 11 mg/dl and 0.3%, respectively. Conclusions Administration of semaglutide for 26 weeks resulted in favorable changes in body composition and glycemic control, suggesting a reduced risk for the development of cardiometabolic disease in obese individuals with SCI. Trial registration: ClinicalTrials.gov identifier: NCT03292315.

Abstract #1400837: Skewness in Body Fat Distribution Pattern Links to Specific Cardiometabolic Disease Risk Profiles

Research on body fat distribution illustrates a heterogeneity within obesity and indicates that the pattern in which a person carries their fat could help determine each individual’s cardiometabolic risk profile. The aim of this study was to evaluate the association between balance of different fat compartments (visceral, subcutaneous, and liver) with incident type 2 diabetes (T2D) and cardiovascular disease (CVD) in the UK Biobank imaging study. Magnetic resonance images were collected in 40,174 participants using a 6-minute neck-to-knee protocol and analyzed for visceral adipose tissue (VAT) volume, abdominal subcutaneous adipose tissue (aSAT) volume, and liver proton density fat fraction (LF) using AMRA® Researcher. To assess body fat distribution patterns independent of BMI, personalized body fat z-scores (VATz, aSATz, and LFz) were calculated for each participant using the distribution of least N=150 matched controls with the same sex and similar BMI. Participants without prevalent T2D and CVD (N=35,138), were partitioned in 3 ways: based on the balance between (1) VATz & LFz using z-scores=0 as cut-points (thus creating 4 groups: VATz< 0 & LFz< 0 (reference [lower VAT and LF than predicted by BMI]); VATz< 0 & LFz >0; VATz >0 & LFz< 0; VATz >0 & LFz >0, (2) VATz & aSATz, and (3) LFz & aSATz. Logistic regression and Cox proportional-hazards models were used to investigate the association of the balance between body fat z-scores with incident T2D and CVD respectively. Models were crude and subsequently adjusted for sex, age, and BMI. The strongest association with incident T2D were found for VATz >0 & LFz >0 (crude odds ratio (cOR) 4.31, 95% CI 2.83-6.78, p< 0.001), VATz >0 & aSATz< 0 (cOR 4.43, 95% CI 2.85-7.11, p< 0.001), and LFz >0 & aSATz< 0 (cOR 2.47, 95% CI 1.62-3.83, p< 0.001). When adjusted for sex, age, and BMI, those with VATz >0 and/or LFz >0 remained significant. For incident CVD, the strongest associations were found for VATz >0 & LFz< 0 (crude hazard ratio (cHR) 1.53, 95% CI 1.34-1.76, p< 0.001) and VATz >0 & aSATz< 0 (cHR 1.54, 95% CI 1.34-1.76, p< 0.001). When adjusted for sex, age, and BMI, only VATz >0 & LFz< 0 remained significant. Excessive accumulation of VAT in relation to BMI (VATz >0) was consistently linked to both T2D and CVD. Excessive accumulation of LF in relation to BMI (LFz >0) was linked to T2D only. Groups with skewed fat distribution patterns showed the highest risk for incident CVD (VATz >0 & LFz< 0 and VATz >0 & aSATz< 0) and T2D (VATz >0 & aSATz< 0). Descriptions of body fat distribution pattern could inform diagnosis and treatment strategies for obesity and related conditions.

46. Optimal Computed Tomography-based Biomarkers for Prediction of Incisional Hernia Formation

PURPOSE: Incisional hernia (IH) is a pervasive surgical disease. Computer vision and machine learning (ML) were used to derive computed tomography (CT)-based features predictive of IH. METHODS: Patients who underwent colorectal surgery between 2005-2017 were identified (n=14,345). Patients who developed IH were matched with those who did not (n=212). Preoperative abdominopelvic CT scans were segmented to derive linear, volumetric, intensity-based, and textural measurements. Optimal biomarkers (OBMs) were derived and used to test ML classifiers (SVMs, Random Forests, Ensemble Boosting) for IH prediction. RESULTS: 279 features were extracted from preoperative CTs. The most predictive combination of OBMs was: 1) abdominopelvic visceral adipose tissue volume (VAT); 2) abdominopelvic intra-abdominal musculature volume; and 3) pelvic VAT to outer abdominal musculature volume (OAM) ratio. ML models using these OBMs were tested, Ensemble Boosting outperformed other models across all metrics. CONCLUSION: These OBMs suggest intra-abdominal volume/pressure is the most salient pathophysiologic mechanism for IH formation. ML models using OBMs are highly predictive of IH. Image analysis is a powerful tool in surgical risk prediction.

Aerobic Exercise Modulates Visceral Adipose Tissue of Estrogen Deprived Rats in an Experimental Model of Dyslipidemia

Abstract Introduction Menopausal women have an increase deposition of body fat and changes in the lipid profile, being especially susceptible to cardiovascular diseases, and type 2 diabetes. However, physical activity can mitigate this situation. Thus, the aim of the present study is to evaluate the effects of moderate aerobic exercise on visceral adipose tissue (VAT) of female LDL-receptor knockout ovariectomized mice. Methods We used 48 animals, divided into six groups (n = 8/per group): sedentary control (SC), sedentary ovariectomized control (SCO), trained ovariectomized control (TCO), sedentary non-ovariectomized LDL-receptor knockout (KS), sedentary ovariectomized LDL-receptor knockout (KOS), and trained LDL-receptor knockout ovariectomized (KOT). We analyzed the VAT through morphometric and stereological parameters in hematoxylin and eosin stained sections. Additionally, we evaluated biochemical parameters as glucose, triglycerides, and total cholesterol. Finally, immunohistochemical techniques for matrix remodeling, inflammation, apoptosis, and oxidative stress were evaluated. Results We observed that menopause is related to increased visceral adiposity, inflammation, oxidative stress, macrophages activity, serum levels of glucose, triglycerides, and total cholesterol. However, exercise was effective in reducing these parameters, as well as being associated with increased vascularization of VAT and interstitial volume density. Conclusions Moderate exercise is a key factor in mitigating the effects of dyslipidemia in estrogen deprivation. However, further studies are needed to corroborate with our findings.

CT-derived body composition associated with lung cancer recurrence after surgery

ObjectivesTo evaluate the impact of body composition derived from computed tomography (CT) scans on postoperative lung cancer recurrence. MethodsWe created a retrospective cohort of 363 lung cancer patients who underwent lung resections and had verified recurrence, death, or at least 5-year follow-up without either event. Five key body tissues and ten tumor features were automatically segmented and quantified based on preoperative whole-body CT scans (acquired as part of a PET-CT scan) and chest CT scans, respectively. Time-to-event analysis accounting for the competing event of death was performed to analyze the impact of body composition, tumor features, clinical information, and pathological features on lung cancer recurrence after surgery. The hazard ratio (HR) of normalized factors was used to assess individual significance univariately and in the combined models. The 5-fold cross-validated time-dependent receiver operating characteristics analysis, with an emphasis on the area under the 3-year ROC curve (AUC), was used to characterize the ability to predict lung cancer recurrence. ResultsBody tissues that showed a standalone potential to predict lung cancer recurrence include visceral adipose tissue (VAT) volume (HR = 0.88, p = 0.047), subcutaneous adipose tissue (SAT) density (HR = 1.14, p = 0.034), inter-muscle adipose tissue (IMAT) volume (HR = 0.83, p = 0.002), muscle density (HR = 1.27, p < 0.001), and total fat volume (HR = 0.89, p = 0.050). The CT-derived muscular and tumor features significantly contributed to a model including clinicopathological factors, resulting in an AUC of 0.78 (95% CI: 0.75–0.83) to predict recurrence at 3 years. ConclusionsBody composition features (e.g., muscle density, or muscle and inter-muscle adipose tissue volumes) can improve the prediction of recurrence when combined with clinicopathological factors.

Determination of lower radiation dose limit for automatic measurement of adipose tissue.

The purpose of this study was to determine the lower limit of radiation dose required to measure visceral adipose tissue (VAT) and subcutaneous adipose tissue (SAT) volumes when a fat quantification and noise reduction techniques (NRTs) are combined. For this purpose, we utilized CT colonography (CTC) images taken at low doses and manually segmented VAT and SAT fat volumes as ground truth. In order to derive the acceptable precision of the measurements needed to estimate the lower limit of radiation dose, we estimated the effect of different positioning during CT scanning on fat measurements using manually segmented VAT and SAT against normal dose. As a result, the acceptable accuracy of SAT and VAT was found to be 94.5% and 85.2%, respectively. Using these thresholds, the lower radiation dose limit required to accurately measure SAT using 5.25-mm slice-thick images was 1.5mGy of size-specific dose estimates (SSDE), while the lower radiation dose limit required to accurately measure VAT was 0.4mGy of SSDE. The lower dose limit for SAT and VAT combined was 1.5mGy, which was equivalent to an estimated effective dose of 0.38mSv. Alternatively, without noise reduction, SAT could not achieve acceptable accuracy even for images with a slice thickness of 5.25mm, while VAT required noise reduction for images with a slice thickness of 1.25mm, but could achieve acceptable accuracy without noise reduction for images with a slice thickness of 5.25mm.