Machine Learning-Based Prediction of Abdominal Subcutaneous Fat Thickness During Pregnancy.

Objective: Current evidence regarding the safety of abdominal subcutaneous injections in pregnant women is limited. In this study, we developed a predictive model for abdominal skin-subcutaneous fat thickness (S-ScFT) by gestational periods (GP) in pregnant women. Methods: A total of 354 cases were measured for S-ScFT. Three machine learning algorithms, namely deep learning, random forest, and support vector machine, were used for S-ScFT predictive modeling and factor analysis for each abdominal site. Data analysis was performed using SPSS and RapidMiner softwares. Results: The deep learning algorithm best predicted the abdominal S-ScFT. The common important variables in all three algorithms for the prediction of abdominal S-ScFT were menarcheal age, prepregnancy weight, prepregnancy body mass index (categorized), large fetus for gestational age, and alcohol consumption. Conclusion: Predicting the safety of subcutaneous injections during pregnancy could be beneficial for managing gestational diabetes mellitus in pregnant women.

Cryolipolysis for abdominal subcutaneous fat reduction: A prospective, multicenter, single arm, clinical study.

Various treatment methods are used for noninvasive body contouring. To evaluate the efficacy and safety of a newly designed cryolipolysis device using a three-dimensional cooling method for abdominal fat reduction. Twenty-five participants with clinically apparent abdominal fat tissue participated in the study. The thickness of fat tissue below the umbilicus level was measured using a caliper at baseline and 12 weeks after the first treatment. The height of abdominal subcutaneous fat tissue on ultrasonography and participant satisfaction were assessed at every visit for 16 weeks. All adverse events (AEs) during the study period were recorded. p values <0.05 were considered statistically significant. Twenty-four participants completed this study; the mean BMI of participants was 29.34 ± 2.36 kg/m2 . The mean thickness of abdominal subcutaneous fat was significantly lower at 12 weeks (40.4 ± 6.8 mm, p < 0.001) than at baseline (49.3 ± 8.5 mm). Differences in the height of abdominal subcutaneous fat compared to that at baseline were 1.02 ± 0.41 cm (12 weeks, p < 0.001) and 1.13 ± 0.44 cm (16 weeks, p < 0.001). Rates of abdominal subcutaneous fat reduction at 12 and 16 weeks compared to that at baseline were 28.45% and 31.13%, respectively. The ratio of abdominal circumference to hip circumference at 12 and 16 weeks was significantly decreased compared to that at baseline. Most participants (95.8%) reported improvement in satisfaction scores at 16 weeks. There were no serious AEs during the entire study period. The study demonstrated the efficacy of a noninvasive cryolipolysis device using a three-dimensional cooling method for reducing abdominal subcutaneous fat.

Efficacy of a Novel Injection Lipolysis to Induce Targeted Adipocyte Apoptosis: A Randomized, Phase IIa Study of CBL-514 Injection on Abdominal Subcutaneous Fat Reduction.

BACKGROUND: CBL-514 is a novel injectable drug that may be safe and efficacious for localized abdominal subcutaneous fat reduction. OBJECTIVES: The aim of this study was to assess the safety and efficacy of CBL-514 in reducing abdominal subcutaneous fat volume and thickness. METHODS: This Phase IIa, open-label, random allocation study consisted of a 6-week treatment period and follow-up at 4 and 8 weeks following the last treatment. Participants were randomly allocated to receive 1.2 mg/cm2 (180 mg), 1.6 mg/cm2 (240 mg), or 2.0 mg/cm2 (300 mg) of CBL-514 with up to 4 treatments, each comprising 60 injections into the abdominal adipose layer. Changes in abdominal subcutaneous fat were assessed by ultrasound at follow-up visits. Treatment-emergent adverse events were recorded. RESULTS: Higher doses of CBL-514 (unit dose, 2.0 and 1.6 mg/cm2) significantly improved the absolute and percentage reduction in abdominal fat volume (P < 0.00001) and thickness (P < 0.0001) compared with baseline. Although the COVID-19 pandemic halted some participant recruitment and follow-ups, analysis was unaffected, even after sample size limitations. CONCLUSIONS: CBL-514 injection at multiple doses up to 300 mg with a unit dose of 2.0 mg/cm2 is safe, well-tolerated, and reduced abdominal fat volume and thickness by inducing adipocyte apoptosis. Although other procedures exist to treat abdominal fat, they have limitations and may cause complications. At a dose of 2.0 mg/cm2, CBL-514 safely and significantly reduced abdominal fat volume by 24.96%, making it a promising new treatment for routine, nonsurgical abdominal fat reduction in dermatologic clinics.

Efficacy and safety of a novel combined 1060-nm and 635-nm laser device for non-invasive reduction of abdominal and submental fat.

The aim of this study was to evaluate the safety and efficacy of combined 1060-nm diode laser and 635-nm low-level laser therapy (LLLT) device for non-invasive reduction of the abdominal and submental fat. Forty-two healthy subjects received single laser treatment on both the abdomen and submental area. Ultrasound images measuring the thickness of abdominal and submental fat were taken at baseline, follow-up at 4, 8, and 12 weeks after treatment. Waist circumference and body weight were also measured at all visits. Adverse events were recorded at all visits. Subjects completed a satisfaction questionnaire at the end of the trial. Twelve weeks after a single treatment with the investigational device, ultrasound images showed statistically significant (P < 0.0001) reductions in abdominal and submental fat by 18.62 and 26.4%, respectively. In addition, significant (P < 0.0001) reduction in waist circumference was observed. Ninety-six percent of subjects rated that they were satisfied. Noted side effects were transient mild to moderate tenderness which subsided within 1 to 3 weeks. No serious treatment-related adverse events were reported. The dual wavelength device combining 1060-nm diode laser with 635-nm LLLT was safe and effective for non-invasive reduction of both abdominal and submental fat.

The role of muscle depletion and visceral adiposity in HCC patients aged 65 and over undergoing TACE.

BACKGROUND: The incidence of hepatocellular carcinoma (HCC) has been increasing among the elderly populations. Trans-arterial chemoembolization (TACE), a widely used first-line non-curative therapy for HCCs is an issue in geriatrics. We investigated the prognosis of elderly HCC patients treated with TACE and determined the factors that affect the overall survival. METHODS: We included 266 patients who were older than 65 years and had received TACE as initial treatment for HCC. We analyzed the skeletal muscle index (SMI) and visceral-to-subcutaneous fat ratio (VSR) around the third lumbar vertebrae using computed tomography scans. Muscle depletion with visceral adiposity (MDVA) was defined by falling below the median SMI and above the median VSR value sex-specifically. We evaluated the overall survival in association with MDVA and other clinical factors. RESULTS: The mean age was 69.9 ± 4.5 years, and 70.3% of the patients were men. According to the Barcelona Clinic Liver Cancer (BCLC) staging system, 29, 136, and 101 patients were classified as BCLC 0, A, and B stages, respectively, and 79 (29.7%) had MDVA. During the median follow-up of 4.1 years, patients with MDVA had a shorter life expectancy than those without MDVA (P = 0.007) even though MDVA group had a higher objective response rate after the first TACE (82.3% vs. 75.9%, P = 0.035). Multivariate analysis revealed that MDVA (Hazard ratio [HR] 1.515) age (HR 1.057), liver function (HR 1.078), tumor size (HR 1.083), serum albumin level (HR 0.523), platelet count (HR 0.996), tumor stage (stage A, HR 1.711; stage B, HR 2.003), and treatment response after the first TACE treatment (HR 0.680) were associated with overall survival. CONCLUSIONS: MDVA is a critical prognostic factor for predicting survival in the elderly patients with HCC who have undergone TACE.

Asociación entre variables ecográficas de adiposidad abdominal y variables analíticas y antropométricas aplicando análisis de correlación canónica en gestantes normopeso / Association between echography variables of abdominal adiposity and analytical and anthropometric variables applying canonical correlation analysis in normal-weight pregnant

RESUMEN Fundamento: La obesidad abdominal en gestantes es un marcador de riesgo cardiometabólico independientemente de la adiposidad general, siendo la ultrasonografía de gran utilidad para distinguir los compartimientos adiposos del abdomen y diagnosticar tal peligro al inicio de la gestación. Objetivo: Determinar asociaciones entre variables ecográficas de adiposidad abdominal y variables analíticas y antropométricas en gestantes normopeso al inicio del embarazo según fenotipos metabólicos empleando análisis de correlación canónica. Metodología: Estudio transversal en 526 embarazadas normopeso, entre 12 y 14 semanas de edad gestacional, atendidas en consulta de ultrasonido del Policlínico Docente Chiqui Gómez, municipio Santa Clara. Se midieron las grasas abdominales subcutánea, preperitoneal y visceral, así como variables antropométricas y analíticas. Se conformaron 3 fenotipos metabólicos, y se aplicó la correlación canónica para determinar el nexo entre las mismas y su comportamiento en los diferentes fenotipos. Resultados: Se identificaron 2 conjuntos de variables con correlaciones canónicas que se incrementaron del fenotipo saludable al metabólicamente obeso con valores de 0.6930 a 0.8955 y 0.9298 respectivamente y alta significancia estadística (p=0.000). Conclusiones: Se demuestra el nexo entre las variables ecográficas de adiposidad abdominal grasa subcutánea y grasa visceral y las variables analíticas resistencia a Ia insulina, producto de acumulación lipídico, índice aterogénico y glucemia, evidenciado por los altos valores de correlaciones canónicas obtenidos según cambia el fenotipo de normopeso saludable al metabólicamente obeso; orientando un nuevo enfoque en la determinación de fenotipos de riesgo metabólico en la gestación temprana en mujeres normopeso.

ABSTRACT Background: Abdominal obesity in pregnant women is an indicator of cardiometabolic risk with non-independence of general adiposity, being the ultrasound very useful to distinguish the abdomen adipose compartments also diagnose this risk at the beginning of pregnancy. Objective: To determine possible associations between the ultrasound variables of abdominal adiposity and those analytical and anthropometric in normal-weight pregnant women at the beginning of pregnancy according to metabolic phenotypes using canonical correlation analysis. Methodology: A cross-sectional study in 526 normal-weight pregnant women, between 12 and 14 weeks of gestational age, assisted in the ultrasound office at Chiqui Gómez teaching polyclinic, in Santa Clara city. Subcutaneous, preperitoneal and visceral abdominal fats were measured, as well as anthropometric and analytical variables. Three metabolic phenotypes were formed, and canonical correlation was applied to determine their relation and also behavior among the different phenotypes. Results: 2 sets of variables were identified with canonical correlations that increased from the healthy to the metabolically obese phenotype with values from 0.6930 to 0.8955 and 0.9298 respectively and high statistical significance (p=0.000). Conclusions: The link between the ultrasound variables of abdominal adiposity, subcutaneous and visceral fat and the analytical insulin resistance, lipid accumulation product, atherogenic index and blood glucose is demonstrated, evidenced by the high values of canonical correlations obtained as the phenotype changes from healthy normal-weight to metabolically obese; guiding a new approach in the resolve of the metabolic risk phenotypes in early gestation in normal-weight women.

Superficial vs Deep Subcutaneous Adipose Tissue: Sex-Specific Associations With Hepatic Steatosis and Metabolic Traits.

CONTEXT: Subcutaneous adipose tissue (SAT) is not homogeneous, as the fascia scarpa separates the deep SAT (dSAT) from the superficial SAT (sSAT). OBJECTIVE: The aim of this study is to evaluate the sex-specific associations of sSAT and dSAT with hepatic steatosis and metabolic syndrome in overweight individuals. METHODS: We recruited 285 individuals with a body mass index (BMI) greater than or equal to 27 and aged 55 to 81 years. Abdominal magnetic resonance imaging was performed around level L4 to L5 to measure visceral adipose tissue (VAT), dSAT, and sSAT volumes. The amount of hepatic fat was quantified by MR spectroscopy. RESULTS: Men had significantly higher volumes of VAT (122.6 cm3 vs 98.7 cm3, P < .001) and had only half the volume of sSAT compared to women adjusted for BMI (50.3 cm3 in men vs 97.0 cm3 in women, P < .001). dSAT correlated significantly with hepatic fat content in univariate analysis (standardized ß = .190, P < .05), while VAT correlated significantly with hepatic steatosis in a multivariate model, adjusted for age, alcohol use, and other abdominal fat compartments (standardized ß = .184, P = .037). Moreover, dSAT in men correlated negatively with HDL cholesterol (standardized ß = -0.165, P = .038) in multivariate analyses. In women with a BMI between 30 and 40, in a multivariate model adjusted for age, alcohol use, and other abdominal fat compartments, VAT correlated positively (standardized ß = -.404, P = .003), and sSAT negatively (standardized ß = -.300, P = .04) with hepatic fat content. CONCLUSION: In men, dSAT is associated with hepatic steatosis and adverse metabolic traits, such as lower HDL cholesterol levels, whereas in women with obesity sSAT shows a beneficial relation with respect to hepatic fat content.

Asociación entre el espesor de la grasa subcutánea abdominal y la esteatosis hepática, las enzimas hepáticas y los lípidos séricos en niños obesos / Association of abdominal subcutaneous fat thickness with hepatic steatosis, liver enzymes, and serum lipids in obese children

Introducción. La obesidad infantil puede causar hiperlipidemia y esteatosis hepática y complicaciones crónicas. Nuestro objetivo fue evaluar la relación entre el espesor de la grasa subcutánea abdominal (GSA) y la esteatosis hepática, las transaminasas y los lípidos séricos en niños obesos.Población y métodos. Estudio retrospectivo en niños (4-18 años) que acudieron a los consultorios externos. Se evaluaron las asociaciones entre el espesor de la GSA mediante ecografía y la esteatosis hepática, alanina aminotransferasa (ALT), aspartato aminotransferasa (AST) y el perfil lipídico sérico.Resultados. Se identificaron 95 niños con esteatosis hepática; el grado 1 fue el más frecuente (73,6 %, n: 70), seguido del grado 2 (21,1 %) y del 3 (5,3 %). El espesor medio (en mm) de la GSA de línea media y flancos fue 38,48 ± 11,53 y 20,91 ± 8,00 en grado 1; 41,23 ± 10,03 y 19,84 ± 6,75 en grado 2, y 63,12 ± 12,08 y 23,22 ± 5,92 en grado 3, respectivamente. El espesor de la GSA de línea media y flancos se correlacionó positivamente con triglicéridos en grado 3; el espesor de la GSA de línea media se correlacionó con el índice de masa corporal, colesterol total, colesterol LDL y AST (r: 0,9; p: 0,037; r: 0,648; p: 0,001; r: 0,387; p: 0,001; r: 0,406; p: 0,001; r: 0,463; p: 0,001; respectivamente) en grado 1.Conclusión. El espesor de la GSA mediante ecografía puede predecir hiperlipidemia en niños obesos con esteatosis hepática de grado 3 e hipercolesterolemia en grado 1.

Introduction. Childhood obesity can cause hyperlipidemia and hepatic steatosis at early age and chronic disease complications in adult life. We aimed to evaluate the relationship between abdominal subcutaneous fat thickness (ASFT) and hepatic steatosis, serum lipid and transaminase levels in obese children.Population and methods. A retrospective study was conducted with children (aged 4-18 years) who presented to outpatient clinic due to obesity. Associations between ASFT as assessed by ultrasonography (US) and hepatic steatosis, alanine transaminase (ALT), aspartate transaminase (AST) and serum lipid profile were evaluated.Results. We identified 95 children, all of which were diagnosed as having hepatic steatosis; the most common type was grade 1 (73.6 %, n: 70), followed by grade 2 (21.1 %) and grade 3 (5.3 %). The mean values of midline and flank ASFT were measured as 38.48 ± 11.53 mm and 20.91 ± 8.00 mm in grade 1; 41.23 ± 10.03 and 19.84 ± 6.75 in grade 2 and 63.12 ± 12.08 and 23.22 ± 5.92 in grade 3 hepatic steatosis, respectively. Midline and flank ASFT correlated positively with triglycerides in grade 3 steatosis, while midline ASFT correlated with body mass index, total cholesterol, low-density lipoprotein cholesterol, and AST (r: 0.9; p: 0.037; r: 0.648, p: 0.001; r: 0.387, p: 0.001; r: 0.406, p: 0.001, r: 0.463, p: 0.001; respectively) in grade 1 steatosis.Conclusion. ASFT as assessed by US may be of predictive value for hyperlipidemia in grade 3 and for hypercholesterolemia in grade 1 hepatic steatosis in obese children.

Abdominal subcutaneous fat thickness as a substitute for BMI in predicting complications in abdominally-based autologous breast reconstruction.

INTRODUCTION: Patient selection for autologous tissue transfer for postmastectomy breast reconstruction often utilizes body mass index (BMI) to risk stratify patients, though it only estimates fat content and does not address fat distribution. This study aims to identify a measurement of abdominal subcutaneous fat thickness (ASFT) from preoperative computed tomography (CT) angiography imaging to better predict complications. METHODS: A retrospective review of patients who underwent an abdominal microvascular free flap breast reconstruction was performed. The average of the bilateral distances from the lateral border of the rectus abdominus to the most proximal point of the dermis at the L4-L5 space was measured on preoperative imaging to estimate ASFT. This measurement was compared to BMI in regards to correlation with any complication, major or minor complications, and donor or recipient site complications. Statistical analysis utilized point-biserial correlations and multivariable logistic regression analyses. RESULTS: Three hundred and nine cases comprising a total of 496 breast reconstructions were identified. BMI did not correlate with any of the grouped complications, while ASFT correlated with occurrence of any complication (p = .003), minor complications (p = .001), and recipient site complications (p = .001). Further analysis revealed ASFT is specifically correlated with fat necrosis (p = .005). In independent multivariable regression models, both BMI (p = .011) and ASFT (p = .001) were significant predictors of fat necrosis. The ASFT model had a BIC of 335.42 compared to the BMI model with a value of 340.89, with smaller numbers representing more predictive models. CONCLUSION: Estimation of ASFT is easily performed and is a significantly better predictor of flap fat necrosis than BMI.

Thickness of carotid artery intima is an independent risk factor for psoriasis.

Psoriasis (PsO) has been associated with lipoprotein abnormalities, visceral adiposity, atherosclerosis, and coronary artery disease (CAD) in several studies; however, data concerning the risk of psoriasis relevant to these parameters is not well established. We aimed to evaluate the relation between PsO and small dense low-density lipoprotein cholesterol (sd-LDL-C), serum lipid profile (SLP), blood pressures, anthropometric measurements, intima media thickness of the common carotid artery (CIMT), distribution of visceral adipose tissue (VAT; evaluated at 3 different measurement sites including VATa, VATb, VATc) along with subcutaneous (Sc-d1) and preperitoneal (Pre-d2) adipose tissue, and disease characteristics, so as to define relevant risk factors for PsO. In this cross-sectional and observational study, 62 patients with plaque-type PsO and 31 age- and sex-matched controls were enrolled. Data about metabolic profile, CIMT and VAT were obtained. There was a significant association between PsO and hypertension, smoking, diastolic blood pressure, sd-LDL-C/LDL-C ratio, CIMT, VATc, and Pre-d2. Following adjustments for hypertension and smoking, sd-LDL-C/LDL-C ratio, CIMT, and Pre-d2 still remained different between patients and controls (P = 0.03, P = 0.043, and P = 0.05, respectively). Each 0.1 unit increase in the CIMT increased the risk of PsO 1.51-fold (95%CI: 1.08 - 2.12, P = 0.016). PsO associates with a predisposition to develop thick preperitoneal fat tissue and thick intima of carotid arteries, all of which contribute to the increased risk of atherosclerosis and subsequent CAD. CIMT was considered as an independent risk factor for PsO.

Associations of DXA-measured abdominal adiposity with cardio-metabolic risk and related markers in early adolescence in Project Viva.

BACKGROUND: Increased visceral adipose tissue (VAT) precedes development of insulin resistance and dyslipidemia in adults. The associations of abdominal adiposity derived from dual-energy X-ray absorptiometry (DXA), including VAT, subcutaneous abdominal adipose tissue (SAAT) and total abdominal adipose tissue (TAAT) with cardio-metabolic risk in adolescents are understudied. OBJECTIVES: We examined the cross-sectional associations of DXA-measured abdominal adiposity with cardio-metabolic risk and related markers in early adolescence (mean [SD] age 13.0 [0.7] years). METHODS: We collected data from 740 adolescents (374 girls and 366 boys) in Project Viva, a U.S. pre-birth cohort. We used DXA estimates of VAT, SAAT and TAAT area. We conducted overall and sex-stratified linear regression models, adjusting for age, sex (in overall models), race/ethnicity, puberty score and body mass index (BMI) z-score. RESULTS: Mean BMI z-score was 0.59 (1.28). After adjustment, greater VAT (per 1 SD score) was associated with higher metabolic risk z-score (ß 0.14 units; 95% CI 0.08, 0.20), higher log high-sensitivity C-reactive protein (ß 0.51 mg/L; 0.36, 0.66) and log leptin (ß 0.36 ng/mL; 0.27, 0.44), and lower log adiponectin (ß -0.08 ug/mL; -0.13, -0.02). SAAT and TAAT showed similar associations as VAT with comparable or greater effect sizes. CONCLUSION: In early adolescence, DXA-measured VAT, SAAT and TAAT are associated with cardio-metabolic risk and related markers, independent of current BMI. Among two adolescents with the same BMI, there is an associated higher cardio-metabolic risk in the adolescent with greater DXA-measured abdominal adiposity.

Abdominal subcutaneous fat quantification in obese patients from limited field-of-view MRI data.

Different types of adipose tissue can be accurately localized and quantified by tomographic imaging techniques (MRI or CT). One common shortcoming for the abdominal subcutaneous adipose tissue (ASAT) of obese subjects is the technically restricted imaging field of view (FOV). This work derives equations for the conversion between six surrogate measures and fully segmented ASAT volume and discusses the predictive power of these image-based quantities. Clinical (gender, age, anthropometry) and MRI data (1.5 T, two-point Dixon sequence) of 193 overweight and obese patients (116 female, 77 male) from a single research center for obesity were analyzed retrospectively. Six surrogate measures of fully segmented ASAT volume (VASAT) were considered: two simple ASAT lengths, two partial areas (Ap-FH, Ap-ASIS) and two partial volumes (Vp-FH, Vp-ASIS) limited by either the femoral heads (FH) or the anterior superior iliac spine (ASIS). Least-squares regression between each measure and VASAT provided slope and intercept for the computation of estimated ASAT volumes (V~ASAT). Goodness of fit was evaluated by coefficient of determination (R2) and standard deviation of percent differences (sd%) between V~ASAT and VASAT. Best agreement was observed for partial volume Vp-FH (sd% = 14.4% and R2 = 0.78), followed by Vp-ASIS (sd% = 18.1% and R2 = 0.69) and AWFASIS (sd% = 23.9% and R2 = 0.54), with minor gender differences only. Other estimates from simple lengths and partial areas were moderate only (sd% > 23.0% and R2 < 0.50). Gender differences in R2 generally ranged between 0.02 (dven) and 0.29 (Ap-FH). The common FOV restriction for MRI volumetry of ASAT in obese subjects can best be overcome by estimating VASAT from Vp-FH using the equation derived here. The very simple AWFASIS can be used with reservation.

Change in abdominal, but not femoral subcutaneous fat CT-radiodensity is associated with improved metabolic profile after bariatric surgery.

BACKGROUND AND AIMS: Computed tomography (CT)-derived adipose tissue radiodensity represents a potential noninvasive surrogate marker for lipid deposition and obesity-related metabolic disease risk. We studied the effects of bariatric surgery on CT-derived adipose radiodensities in abdominal and femoral areas and their relationships to circulating metabolites in morbidly obese patients. METHODS AND RESULTS: We examined 23 morbidly obese women who underwent CT imaging before and 6 months after bariatric surgery. Fifteen healthy non-obese women served as controls. Radiodensities of the abdominal subcutaneous (SAT) and visceral adipose tissue (VAT), and the femoral SAT, adipose tissue masses were measured in all participants. Circulating metabolites were measured by NMR. At baseline, radiodensities of abdominal fat depots were lower in the obese patients as compared to the controls. Surprisingly, radiodensity of femoral SAT was higher in the obese as compared to the controls. In the abdominal SAT depot, radiodensity strongly correlated with SAT mass (r = -0.72, p < 0.001). After surgery, the radiodensities of abdominal fat increased significantly (both p < 0.01), while femoral SAT radiodensity remained unchanged. Circulating ApoB/ApoA-I, leucine, valine, and GlycA decreased, while glycine levels significantly increased as compared to pre-surgical values (all p < 0.05). The increase in abdominal fat radiodensity correlated negatively with the decreased levels of ApoB/ApoA-I ratio, leucine and GlycA (all p < 0.05). The increase in abdominal SAT density was significantly correlated with the decrease in the fat depot mass (r = -0.66, p = 0.002). CONCLUSION: Higher lipid content in abdominal fat depots, and lower content in femoral subcutaneous fat, constitute prominent pathophysiological features in morbid obesity. Further studies are needed to clarify the role of non-abdominal subcutaneous fat in the pathogenesis of obesity. CLINICAL TRIAL REGISTRATION NUMBER: NCT01373892.

The role of insulin resistance in the relation of visceral, abdominal subcutaneous and total body fat to cardiovascular function.

BACKGROUND AND AIMS: The separate cardiovascular effects of type 2 diabetes and adiposity remain to be examined. This study aimed to investigate the role of insulin resistance in the relations of visceral (VAT), abdominal subcutaneous (aSAT) adipose tissue and total body fat (TBF) to cardiovascular remodeling. METHODS AND RESULTS: In this cross-sectional analysis of the population-based Netherlands Epidemiology of Obesity study, 914 middle-aged individuals (46% men) were included. Participants underwent magnetic resonance imaging. Standardized linear regression coefficients (95%CI) were calculated, adjusted for potential confounding factors. All fat depots and insulin resistance (HOMA-IR), separate from VAT and TBF, were associated with lower mitral early and late peak filling rate ratios (E/A): -0.04 (-0.09;0.01) per SD (54 cm2) VAT; -0.05 (-0.10;0.00) per SD (94 cm2) aSAT; -0.09 (-0.16;-0.02) per SD (8%) TBF; -0.11 (-0.17;-0.05) per 10-fold increase in HOMA-IR, whereas VAT and TBF were differently associated with left ventricular (LV) end-diastolic volume: -8.9 (-11.7;-6.1) mL per SD VAT; +5.4 (1.1;9.7) mL per SD TBF. After adding HOMA-IR to the model to evaluate the mediating role of insulin resistance, change in E/A was -0.02 (-0.07;0.04) per SD VAT; -0.03 (-0.08;0.02) per SD aSAT; -0.06 (-0.13;0.01) per SD TBF, and change in LV end-diastolic volume was -7.0 (-9.7;-4.3) mL per SD VAT. In women, adiposity but not HOMA-IR was related to higher aortic arch pulse wave velocity. CONCLUSION: Insulin resistance was associated with reduced diastolic function, separately from VAT and TBF, and partly mediated the associations between adiposity depots and lower diastolic function.

Interesting case of an abdominal wall Merkel cell carcinoma highlighting the importance of developing an Australian clinical practice guideline.

A 66-year-old Australian male farmer was referred for management of an asymptomatic, rapidly expanding, anterior abdominal wall mass. It was firm and well circumscribed. There were no overlying skin changes, constitutional symptoms or weight loss. His medical history included small bowel obstruction and resection from a Meckel's diverticulitis and a 40-pack-year smoking history. Core biopsy was suggestive of a neuroendocrine tumour and Gallium-68-Dodecane-Tetraacetic-Acid (68GaTate) positron emission tomography revealed an avid solitary lesion confined to the subcutaneous space in the left anterior abdominal wall. Wide local excision was performed, and histopathology revealed Merkel cell carcinoma (MCC). Although classically regarded as a primary cutaneous neuroendocrine tumour, MCC may originate from the subcutaneous fat without obvious skin involvement. Older patients with asymptomatic, rapidly enlarging lesions, particularly if immunosuppressed, with significant ultraviolet sunlight exposure, should raise a high index of suspicion for MCC. Like melanoma, non-metastatic MCC should be treated aggressively for best prognosis.

Hepatic fat is a stronger correlate of key clinical and molecular abnormalities than visceral and abdominal subcutaneous fat in youth.

INTRODUCTION: Body fat distribution is strongly associated with cardiometabolic disease (CMD), but the relative importance of hepatic fat as an underlying driver remains unclear. Here, we applied a systems biology approach to compare the clinical and molecular subnetworks that correlate with hepatic fat, visceral fat, and abdominal subcutaneous fat distribution. RESEARCH DESIGN AND METHODS: This was a cross-sectional sub-study of 283 children/adolescents (7-19 years) from the Yale Pediatric NAFLD Cohort. Untargeted, high-resolution metabolomics (HRM) was performed on plasma and combined with existing clinical variables including hepatic and abdominal fat measured by MRI. Integrative network analysis was coupled with pathway enrichment analysis and multivariable linear regression (MLR) to examine which metabolites and clinical variables associated with each fat depot. RESULTS: The data divided into four communities of correlated variables (|r|>0.15, p<0.05) after integrative network analysis. In the largest community, hepatic fat was associated with eight clinical biomarkers, including measures of insulin resistance and dyslipidemia, and 878 metabolite features that were enriched predominantly in amino acid (AA) and lipid pathways in pathway enrichment analysis (p<0.05). Key metabolites associated with hepatic fat included branched-chain AAs (valine and isoleucine/leucine), aromatic AAs (tyrosine and tryptophan), serine, glycine, alanine, and pyruvate, as well as several acylcarnitines and glycerophospholipids (all q<0.05 in MLR adjusted for covariates). The other communities detected in integrative network analysis consisted of abdominal visceral, superficial subcutaneous, and deep subcutaneous fats, but no clinical variables, fewer metabolite features (280, 312, and 74, respectively), and limited findings in pathway analysis. CONCLUSIONS: These data-driven findings show a stronger association of hepatic fat with key CMD risk factors compared with abdominal fats. The molecular network identified using HRM that associated with hepatic fat provides insight into potential mechanisms underlying the hepatic fat-insulin resistance interface in youth.

Estimation of abdominal subcutaneous fat volume of obese adults from single-slice MRI data - Regression coefficients and agreement.

PURPOSE: Cross-sectional imaging is increasingly used to quantify adipose tissue compartments in subjects with overweight or obesity. The lack of ionizing radiation makes magnetic resonance imaging (MRI) highly preferable to computed tomography (CT) although it is generally less standardized and time-consuming. Fat areas of single or stacks of neighboring slices have previously been considered as surrogates to avoid laborious processing of whole abdominal data-but studies are inconsistent in design and results. The present work therefore analyzed a relatively large number of overweight or obese adults and involved a total of eight landmarks and two surrogates (slice and stack). The goals were to identify the most reliable estimators of abdominal subcutaneous adipose tissue (ASAT) volume for both genders and to relate the findings to the pertinent literature. MATERIAL AND METHODS: Anthropometric and fat-sensitive 1.5 T MRI data of 193 patients (116 female, 77 male) from different IRB-approved studies at a single clinical research institution (IFB Adiposity Diseases, University Medicine Leipzig, Germany) were analyzed retrospectively. Mean (± SD) age and BMI were 51.5 (± 12.4) years and 33.7 (± 3.9) kg/m2 for females versus 57.6 (± 12.4) years and 32.1 (± 3.7) kg/m2 for males. Areas of selected axial slices (10 mm thick, 0.5 mm gap) and of stacks of five slices at common landmarks - intervertebral disc spaces L1/L2 to L5/S1, anterior superior iliac spine (ASIS), femoral head (FH) and umbilicus (UM) - were considered as estimators for ASAT volume (reference). Agreement between simple areas and reference volumes was asssessed by linear regression (coefficient of determination R2) as well as standard deviations of percent differences sd% between estimated and measured volumes. RESULTS: ASAT volumes ranged from 6.61 to 21.94 L for females (mean: 13.37 L) and from 5.42 to 17.90 L (mean: 9.89 L) for males. The smallest sd% (8.4 %-10.1 %) and largest R2 values (0.86-0.92) for single slices were observed for three candidate slice positions that were also associated with the highest ASAT volume fraction: L4/L5, L5/S1 and UM. The stack estimates for these landmarks were overall somewhat better (7.3 %-9.7 %, 0.88-0.94, respectively). The differences in sd% between genders ranged between 0.2 % and 1.1 %. CONCLUSION: ASAT volume in overweight or obese patients can be readily estimated with good accuracy from a single MRI slice centered at intervertebral disc space L5/S1 for both genders. Disc space L4/L5 or the umbilicus are nearly equivalent landmarks, in particular for male subjects. The extension to stack measures may yield too little improvement to justify the extra effort. Landmarks like ASIS, FH or the remaining lumbar disc spaces are considered as unreliable.

Electrical Impedance Tomography-Based Abdominal Subcutaneous Fat Estimation Method Using Deep Learning.

This paper proposes a deep learning method based on electrical impedance tomography (EIT) to estimate the thickness of abdominal subcutaneous fat. EIT for evaluating the thickness of abdominal subcutaneous fat is an absolute imaging problem that aims at reconstructing conductivity distributions from current-to-voltage data. Existing reconstruction methods based on EIT have difficulty handling the inherent drawbacks of strong nonlinearity and severe ill-posedness of EIT; hence, absolute imaging may not be possible using linearized methods. To handle nonlinearity and ill-posedness, we propose a deep learning method that finds useful solutions within a restricted admissible set by accounting for prior information regarding abdominal anatomy. We determined that a specially designed training dataset used during the deep learning process significantly reduces ill-posedness in the absolute EIT problem. In the preprocessing stage, we normalize current-voltage data to alleviate the effects of electrodeposition and body geometry by exploiting knowledge regarding electrode positions and body geometry. The performance of the proposed method is demonstrated through numerical simulations and phantom experiments using a 10 channel EIT system and a human-like domain.

Metabolomics profiling of visceral and abdominal subcutaneous adipose tissue in colorectal cancer patients: results from the ColoCare study.

PURPOSE: Underlying mechanisms of the relationship between body fatness and colorectal cancer remain unclear. This study investigated associations of circulating metabolites with visceral (VFA), abdominal subcutaneous (SFA), and total fat area (TFA) in colorectal cancer patients. METHODS: Pre-surgery plasma samples from 212 patients (stage I-IV) from the ColoCare Study were used to perform targeted metabolomics. VFA, SFA, and TFA were quantified by computed tomography scans. Partial correlation and linear regression analyses of VFA, SFA, and TFA with metabolites were computed and corrected for multiple testing. Cox proportional hazards were used to assess 2-year survival. RESULTS: In patients with metastatic tumors, SFA and TFA were statistically significantly inversely associated with 16 glycerophospholipids (SFA: pFDR range 0.017-0.049; TFA: pFDR range 0.029-0.048), while VFA was not. Doubling of ten of the aforementioned glycerophospholipids was associated with increased risk of death in patients with metastatic tumors, but not in patients with non-metastatic tumors (phet range: 0.00044-0.049). Doubling of PC ae C34:0 was associated with ninefold increased risk of death in metastatic tumors (Hazard Ratio [HR], 9.05; 95% confidence interval [CI] 2.17-37.80); an inverse association was observed in non-metastatic tumors (HR 0.17; 95% CI 0.04-0.87; phet = 0.00044). CONCLUSION: These data provide initial evidence that glycerophospholipids in metastatic colorectal cancer are uniquely associated with subcutaneous adiposity, and may impact overall survival.