Quantification Of Visceral Fat Research Articles

Role of CT-based body composition parameters in the course of COVID-19.

A significant correlation is observed between the course of coronavirus disease 2019 (COVID-19) and body composition parameters including visceral fat quantification, muscle mass, and hepatic attenuation. The aim of the study was to investigate the correlation between the extent of lung involvement and various computed tomography (CT) parameters, as well as laboratory findings in COVID-19 patients. A retrospective analysis was conducted on 72 adult patients with laboratory-confirmed severe acute respiratory syndrome coronavirus 2 infection who underwent two consecutive thorax CT scans at least 2 weeks apart. The patients were divided into two groups, as progressive and nonprogressive, based on the presence of two consecutive CT scans. Skeletal muscle area (SMA), subcutaneous fat area (SFA), visceral fat area (VFA), total fat area (TFA), liver-to-spleen (L/S) density ratio, and laboratory findings were compared between the groups. The correlation between the extent of lung involvement and CT parameters, as well as the laboratory findings were assessed. A total of 72 patients were included in the study, with 34 (47.2%) females and 38 (52.8%) males. Hemoglobin levels were significantly lower in the progressive group compared to the nonprogressive group. C-reactive protein (CRP) values were higher in the progressive group at follow-up. The nonprogressive group exhibited decreases in the SFA, VFA, and TFA, while liver density increased. The progressive group showed a decrease in the twelfth thoracic vertebra (T12) paravertebral muscle area and muscle index. In the comparison of the laboratory and radiological data in the course of COVID-19, white blood cell (WBC) and neutrophil counts increased, SMA T12, and the skeletal muscle index (SMI) decreased in the lung progressive group. Hemoglobin and CRP levels at admission may indicate disease progression. Future studies are warranted to increase the reliability with larger series.

Quantification of Visceral Fat at the L5 Vertebral Body Level in Patients with Crohn's Disease Using T2-Weighted MRI.

The umbilical or L3 vertebral body level is often used for body fat quantification using computed tomography. To explore the feasibility of using clinically acquired pelvic magnetic resonance imaging (MRI) for visceral fat measurement, we examined the correlation of visceral fat parameters at the umbilical and L5 vertebral body levels. We retrospectively analyzed T2-weighted half-Fourier acquisition single-shot turbo spin echo (HASTE) MR axial images from Crohn's disease patients who underwent MRI enterography of the abdomen and pelvis over a three-year period. We determined the area/volume of subcutaneous and visceral fat from the umbilical and L5 levels and calculated the visceral fat ratio (VFR = visceral fat/subcutaneous fat) and visceral fat index (VFI = visceral fat/total fat). Statistical analyses involved correlation analysis between both levels, inter-rater analysis between two investigators, and inter-platform analysis between two image-analysis platforms. Correlational analysis of 32 patients yielded significant associations for VFI (r = 0.85; p < 0.0001) and VFR (r = 0.74; p < 0.0001). Intraclass coefficients for VFI and VFR were 0.846 and 0.875 (good agreement) between investigators and 0.831 and 0.728 (good and moderate agreement) between platforms. Our study suggests that the L5 level on clinically acquired pelvic MRIs may serve as a reference point for visceral fat quantification.

Opportunistic Screening at Abdominal CT: Use of Automated Body Composition Biomarkers for Added Cardiometabolic Value.

Abdominal CT is a frequently performed imaging examination for a wide variety of clinical indications. In addition to the immediate reason for scanning, each CT examination contains robust additional data on body composition that generally go unused in routine clinical practice. There is now growing interest in harnessing this additional information. Prime examples of cardiometabolic information include measurement of bone mineral density for osteoporosis screening, quantification of aortic calcium for assessment of cardiovascular risk, quantification of visceral fat for evaluation of metabolic syndrome, assessment of muscle bulk and density for diagnosis of sarcopenia, and quantification of liver fat for assessment of hepatic steatosis. All of these relevant biometric measures can now be fully automated through the use of artificial intelligence algorithms, which provide rapid and objective assessment and allow large-scale population-based screening. Initial investigations into these measures of body composition have demonstrated promising performance for prediction of future adverse events that matches or exceeds the best available clinical prediction models, particularly when these CT-based measures are used in combination. In this review, the concept of CT-based opportunistic screening is discussed, and an overview of the various automated biomarkers that can be derived from essentially all abdominal CT examinations is provided, drawing heavily on the authors' experience. As radiology transitions from a volume-based to a value-based practice, opportunistic screening represents a promising example of adding value to services that are already provided. If the potentially high added value of these objective CT-based automated measures is ultimately confirmed in subsequent investigations, this opportunistic screening approach could be considered for intentional CT-based screening. ©RSNA, 2021.

Sonographic Measurement of Visceral Fat Thickness as a Correlate of Existing Metabolic Syndrome- A Cross-sectional Study

Introduction: Metabolic syndrome is a well-known disease of multiple risk factors that has at its core, insulin resistance accompanying abnormal adipose deposition and function. Multiple studies demonstrate a potential relationship between Visceral Fat Thickness (VFT) and metabolic syndrome. Ultrasound provides a radiation free low-cost alternative, which is high reproducible in the quantification of visceral fat and can act as an effective screening modality. The simplicity of the method combined with its objectiveness makes it advantageous for accurate measurement of VFT. Aim: To correlate of sonographic measurement of VFT with existing metabolic syndrome. Materials and Methods: This cross-sectional study was conducted on all patients that underwent ultrasound at the study center between August 2016 to August 2019 and were clinically suspected of suffering from metabolic syndrome at the Endocrinology Outpatient Department (OPD). Collation of data into three categories based on VFT (&lt;7 cm, 7 to 10 cm and &gt;10 cm) was done. The patients in each category underwent further testing and metabolic syndrome was either ruled out or diagnosed. Results: The study cohort comprised of 2022 patients. The VFT ranged between 4 and 16 with a mean value of 10.8 and standard deviation of 2.8. The percentage of patients with metabolic syndrome increased in proportion to the increased VFT. VFT &gt;10 cm was found to have specificity and Positive Predictive Value (PPV) 92.52% and 92.53% respectively while VFT &lt;7 cm was found to have a sensitivity and Negative Predictive Value (NPV) of 95.11% and 95.10%, respectively. Conclusion: Ultrasound seems to be the best screening tool for the assessment of intra-abdominal fat deposition as the number of VFT subjects with metabolic syndrome in Category 1 was higher.

New index of abdominal obesity, a body shape index, is BMI-independently associated with systemic arterial stiffness in real-world Japanese population.

To clarify that the new index of abdominal obesity, a body shape index (ABSI), is associated with obesity-related metabolic disorders and arterial stiffness. We analyzed the cross-sectional data from 62,514 Japanese subjects (mean age 44.4years, mean body mass index (BMI) 22.2kg/m2) without a past history of cardiovascular disease, stroke, or treatment for obesity-related metabolic disorders. Various body adiposity indices including BMI, waist circumference (WC), and ABSI were evaluated for abilities to indicate metabolic disorders and arterial stiffness assessed by cardio-ankle vascular index (CAVI). WC, WC/height ratio, and WC/BMI ratio correlated with BMI regardless of gender or obesity, whereas ABSI hardly correlated with BMI. ROC analyses demonstrated that ABSI had the highest discriminatory power in predicting high CAVI (≥90th percentile) compared to other body adiposity indices, and the cut-off value was 0.080. Increases in ABSI as well as BMI reflected severity of metabolic disorders. After adjusting for confounders identified by multiple regression analysis, adjusted CAVI correlated positively with ABSI, whereas an inverted relationship was observed between adjusted CAVI and BMI. Additionally, the contribution of high ABSI (≥0.080) for high CAVI was independent of gender, age, obesity, and obesity-related metabolic disorders in the multivariate logistic regression model. ABSI is an easily calculated index of abdominal obesity which reflects metabolic disorders and systemic arterial stiffening, and may be useful in primary health screening even without any medical equipment for visceral fat quantification.

Precision of the Hologic DXA in the Assessment of Visceral Adipose Tissue

Introduction: Visceral fat, also known as visceral adipose tissue (VAT), has been the focus of intensive research over the past several yr, as ground breaking studies have investigated its possible role in predicting long-term cardiac dysfunction, hypertension, and diabetes. Historically, magnetic resonance imaging and computed tomography were the instruments of choice for visceral fat quantification. However, with the introduction of visceral fat assessment software for Dual-energy X-ray Absorptiometry (DXA) scanners, DXA's use for VAT assessment has become increasingly common. To effectively utilize DXA in future VAT research studies, information about their precision and accuracy must be known. This study provides novel information regarding the precision of the Hologic Horizon DXA scanner in the assessment of VAT. Methods: Sixty individuals (32.7 ± 17.1 yr, 51% male, 40% with body mass index (BMI) > 25 kg/m2) above the age of 16 years were recruited to participate in this study. Subjects found to be pregnant, have a lumbar vertebral compression fracture, nonremovable metal implants in the abdomen, or scoliosis/lordosis/kyphosis were excluded from the study. All subjects underwent 3 consecutive whole body scans on a Hologic Horizon A DXA scanner. Results: VAT mass ranged from 102 g to 1454 g. VAT precision improved with increasing BMI (p = 0.025): coefficient of variation (%CV) was 15.2% for underweight subjects (n = 2), 7.1% for healthy subjects (n = 34), 6.4% for overweight subjects (n = 18), and 4.7% for obese subjects (n = 6). Conclusions: VAT measurement by Hologic DXA displays a satisfactory level of precision in individuals with a BMI of >18.5 kg/m2. Precision was found to be higher in those with the greatest risk of cardio-metabolic dysfunction (individuals with high VAT). Due to its low cost, brief examination time, noninvasiveness, and limited radiation exposure, DXA may be considered the tool of choice for VAT determination in future studies.

Validation of a DIXON-based fat quantification technique for the measurement of visceral fat using a CT-based reference standard.

The purpose of the study is to determine whether a novel semi-automated DIXON-based fat quantification algorithm can reliably quantify visceral fat using a CT-based reference standard. This was an IRB-approved retrospective cohort study of 27 subjects who underwent abdominopelvic CT within 7days of proton density fat fraction (PDFF) mapping on a 1.5T MRI. Cross-sectional visceral fat area per slice (cm2) was measured in blinded fashion in each modality at intervertebral disc levels from T12 to L4. CT estimates were obtained using a previously published semi-automated computational image processing system that sums pixels with attenuation - 205 to - 51HU. MR estimates were obtained using two novel semi-automated DIXON-based fat quantification algorithms that measure visceral fat area by spatially regularizing non-uniform fat-only signal intensity or de-speckling PDFF 2D images and summing pixels with PDFF ≥ 50%. Pearson's correlations and Bland-Altman analyses were performed. Visceral fat area per slice ranged from 9.2 to 429.8cm2 for MR and from 1.6 to 405.5cm2 for CT. There was a strong correlation between CT and MR methods in measured visceral fat area across all studied vertebral body levels (r = 0.97; n = 101 observations); the least (r = 0.93) correlation was at T12. Bland-Altman analysis revealed a bias of 31.7cm2 (95% CI [- 27.1]-90.4cm2), indicating modestly higher visceral fat assessed by MR. MR- and CT-based visceral fat quantification are highly correlated and have good cross-modality reliability, indicating that visceral fat quantification by either method can yield a stable and reliable biomarker.

A retrospective investigation of abdominal visceral fat, body mass index (BMI), and active smoking as risk factors for donor site wound healing complications after free DIEP flap breast reconstructions

The deep inferior epigastric artery perforator (DIEP) flap is one of the most common techniques for breast reconstruction. Body mass index (BMI) is considered as an important predictor of donor site healing complications such as wound dehiscence. The use of computed tomography (CT) proved to be a precise and objective method to assess visceral adipose tissue. It remains unclear whether quantification of visceral fat provides more accurate predictions of abdominal wound healing complications than BMI. A total of 97 patients with DIEP flap were retrospectively evaluated. Patients' abdominal visceral fat (AVF) was quantified on CT angiography (CTA). The patients were postoperatively assessed for abdominal wound healing complications. We analyzed for the correlations between AVF, BMI, and dehiscence and established a logistic regression model to assess the potential high-profile predictors in anatomic and patient characteristics such as weight, smoking, and diabetes. We included 97 patients, and of them, 24 patients (24.7%) had some degree of abdominal dehiscence. No significant differences were observed between the dehiscence group and the non-dehiscence group, except for smoking (p = 0.002). We found a significant correlation between AVF and BMI (R = 0.282, p = 0.005), but neither was significant in predicting donor site dehiscence. Smoking greatly increased the likelihood of developing wound dehiscence (OR = 11.4, p = < 0.001). AVF and BMI were not significant predictors of abdominal wound healing complications after DIEP flap reconstruction. This study established active smoking (OR = 11.4, p = < 0.001) as the significant risk factor that contributed to the development of abdominal wound dehiscence in patients with DIEP.

Morphometric measurements of systemic atherosclerosis and visceral fat: Evidence from an autopsy study.

BackgroundMorphometric measurements of systemic atherosclerosis and direct quantification of visceral fat are only possible using materials from autopsy studies. However, the few autopsy studies that have investigated the association of visceral fat with atherosclerosis had small sample sizes and focused on coronary arteries of young or middle-aged White subjects. We aimed to investigate the association of pericardial fat (PF) and abdominal visceral fat (AVF) with atherosclerosis in the aorta, coronary, carotid, and cerebral arteries in a large autopsy study.Materials and methodsWe evaluated deceased subjects aged 30 years or above. We dissected and weighted the PF and the AVF and evaluated the atherosclerotic burden in the aorta, as well as the carotid, coronary, and cerebral arteries using morphometric measurements. We also investigated the interaction of PF and AVF with age regarding the atherosclerotic burden.ResultsThe mean age of the 240 included subjects was 64.8±15.3 years, and 63% was male. Greater PF was associated with a higher degree of aortic atherosclerosis after adjusting for confounding variables (coefficient = 4.39, 95% CI = 0.83; 7.94, p = 0.02). Greater AVF was associated with a higher coronary stenosis index (coefficient = 1.49, 95% CI = 0.15; 2.83, p = 0.03) and a greater number of coronary plaques (coefficient = 0.71, 95% CI = 0.24; 1.19, p = 0.003). We did not find an association of PF or AVF with carotid or cerebral atherosclerotic burden. We found a significant interaction of AVF (coefficient = -0.08; 95% CI = -0.14; -0.02, p = 0.009) and PF (coefficient = -0.87, 95% CI = -1.70; -0.04, p = 0.04) with age regarding carotid artery atherosclerotic burden.ConclusionsGreater AVF was associated with greater atherosclerotic burden and extent in coronary arteries, while greater PF correlated with a higher degree of atherosclerosis in the aorta.

Development and validation of visceral fat quantification as a surrogate marker for differentiation of Crohn's disease and intestinal tuberculosis.

Crohn's disease (CD) and intestinal tuberculosis (ITB) have close phenotypic resemblance. Mesenteric fat (a component of visceral fat [VF]) hypertrophy and fat wrapping, which is visible radiologically as fibrofatty proliferation, is seen more commonly in CD than in ITB. The present study was conducted to study the role of VF in differentiating CD and ITB. Visceral fat area and subcutaneous (SC) fat area were measured on computed tomography in two cohorts (development and validation). VF/SC ratio was also calculated for all patients. In the development cohort, retrospective data collection was carried out for 75 patients with CD and ITB who were on follow-up from January 2012 to November 2014. In the validation cohort, 82 patients were recruited prospectively from December 2014 to December 2015 and were diagnosed as CD or ITB according to standard diagnostic criteria. Visceral fat area and VF/SC ratio were significantly higher in CD patients (n = 42: development, n = 46: validation) than in ITB patients (n = 33: development, n = 36: validation) in both the development (106.2 ± 63.5 vs 37.3 ± 22, P = <0.001; 1.1 ± 0.57 vs 0.43 ± 0.24, P = <0.001) and validation cohorts (102.2 ± 69.8 vs 55.8 ± 44.9, P = 0.01; 1.2 ± 0.68 vs 0.56 ± 0.33, P = <0.001). A cut-off of 0.63 for VF/SC ratio in the development cohort had a high sensitivity (82%) and specificity (81%) in differentiating CD and ITB. Similar sensitivity (81%) and specificity (78%) were seen when this cut-off was applied in the validation cohort. The VF/SC ratio is a simple, cost-effective, non-invasive and single objective parameter with a good sensitivity and specificity to differentiate CD and ITB.

Quantification of hepatic and visceral fat by CT and MR imaging: relevance to the obesity epidemic, metabolic syndrome and NAFLD.

Trends in obesity have continued to increase in the developed world over the past few decades, along with related conditions such as metabolic syndrome, which is strongly associated with this epidemic. Novel and innovative methods to assess relevant obesity-related biomarkers are needed to determine the clinical significance, allow for surveillance and intervene if appropriate. Aggregations of specific types of fat, specifically hepatic and visceral adiposity, are now known to be correlated with these conditions, and there are a variety of imaging techniques to identify and quantify their distributions and provide diagnostic information. These methods are particularly salient for metabolic syndrome, which is related to both hepatic and visceral adiposity but currently not defined by it. Simpler non-specific fat measurements, such as body weight, abdominal circumference and body mass index are more frequently used but lack the ability to characterize fat location. In addition, non-alcoholic fatty liver disease (NAFLD) is a related condition that carries relevance not only for obesity-related diseases but also for the progression of the liver-specific disease, including non-alcoholic steatohepatitis and cirrhosis, albeit at a much lower frequency. Recent CT and MRI techniques have emerged to potentially optimize diagnosing metabolic syndrome and NAFLD through non-invasive quantification of visceral fat and hepatic steatosis with high accuracy. These imaging modalities should aid us in further understanding the relationship of hepatic and visceral fat to the obesity-related conditions such as metabolic syndrome, NAFLD and cardiovascular disease.

The visceral fat compartment is independently associated with changes in urine constituent excretion in a stone forming population

The objective of this study was to identify the independent effect of visceral fat on urine constituent excretion in a stone forming population. Using a database of 382 kidney stone patients with available visceral fat quantification, we created multiple linear regression models predicting changes in urinary solutes based on visceral fat area and body mass-index, divided by gender. Chi-square tests were used to compare stone composition by body mass-index and visceral fat area. Visceral fat predicts increases in urinary creatinine, sodium, and volume in men, but only urinary phosphate in women. In women, total body mass-index does not appear to modify this effect, but in men it is more pronounced in overweight patients for creatinine and volume only. Elevated visceral fat is associated with increased probability of uric acid stone composition. Different fat compartments likely effect urine composition in different ways. This effect appears to be different in men and women. Understanding and quantifying the effects of different fat compartments is probably important to understanding the metabolism of urolithiasis.

Quantification of Visceral Fat Using Dual-Energy X-Ray Absorptiometry and Its Reliability According to the Amount of Visceral Fat in Korean Adults

Recently, a fully automated method for segmenting abdominal fat into subcutaneous fat and visceral fat (VF) within the android region using dual-energy X-ray absorptiometry (DXA) has been newly developed. The purpose of this study was to validate a new DXA method by comparing it to the gold standard, computed tomography (CT), in the Korean population. Furthermore, we examined its reliability regarding VF and explored whether it is applicable to the Asian population, which has relatively larger amount of VF. We studied 123 adult men and women, aged 22–73 yr, representing a wide range of body mass index values (17.1–36.0 kg/m2), who underwent both DXA and CT in a fasting state within 1 h. The coefficient of determination (r2) for regression of the CT on DXA values was 0.892 for females, 0.838 for males, and 0.931 combined. Bland-Altman bias was −451.4 cm3 with 95% limits of agreement of 149.8 to −1052.6 cm3. The DXA-measured VF showed a better correlation with CT-measured VF volume than common indices for adiposity, including the body mass index and waist circumference. There was a lesser discrepancy ratio between DXA- and CT-measured VF with an increase of VF volume. DXA, a relatively convenient, inexpensive, and safe method with minimum radiation dosage, can be a reliable technique for VF assessment in the Asian population.

Visceral fat quantification in asymptomatic adults using abdominal CT: is it predictive of future cardiac events?

The purpose of this study was to determine if quantifying visceral adipose tissue (VAT) at CT in asymptomatic adults can predict the likelihood of future cardiac events. Subcutaneous and visceral fat volumes were obtained from abdominal CT utilizing a validated semi-automated software tool in 663 asymptomatic adults (mean age 57.3 years, 379F/284M) undergoing colorectal screening. Patients were followed for subsequent cardiac events, defined as myocardial infarction or coronary intervention for a mean follow-up interval of 7.0 ± 1.4 years. Relevant clinical data including Framingham risk score (FRS) were also collected. Statistical analysis included logistic regression, Pearson correlation coefficients, and Welch and Wilcoxon rank sum tests. Cardiac events were documented in 32 subjects (4.8%) an average 3.0 years after index CT. FRS was predictive of future cardiac events, signified by a higher score (mean score 11.9 vs. 7.4; p < 0.001). HDL levels were significantly lower in the cardiac event cohort (mean 52.2 vs. 61.0; p < 0.01). None of the other clinical variables were predictive and none of the CT-based fat measurements (visceral, subcutaneous, and total adipose tissue; visceral fat %) correlated with future cardiac events (p = 0.561–0.886). Mean visceral fat % in the cardiac event cohort was 38.1% vs. 39.1% for the non-event group. Quantification of VAT at abdominal CT was not predictive of future cardiac events in this asymptomatic cohort, whereas HDL levels and FRSs correlated well with risk.

Association of Visceral Obesity and Glomerulomegaly Among Kidney Donors.

OBJECTIVE: Due to increasing demand and shortage of kidneys for donation, there has been a liberalization of criteria with obese donors now being increasingly accepted. However, obesity causes glomerulomegaly, which is an established risk factor for future chronic kidney disease. Identifying a non-invasive obesity pattern most closely associated with glomerulomegaly may help inform the living kidney donor selection. METHODS: Implantation renal biopsy sections were reviewed on 1075 kidney donors (between 1999 and 2012), and the mean non-sclerotic glomerular volumes determined using the Weibel and Gomez stereological model. The 20 kidney donors with the largest glomerular volume were age and gender matched to the 20 kidney donors with the smallest glomerular volume. Abdominal obesity patterns were characterized from pre-donation abdominal CT images. The subcutaneous and visceral fat areas were measured at the umbilicus. Peri-renal (deep to the fascia but superficial to the capsule and para-renal (superficial to the fascia) fat for both kidneys were measured on cross-sectional scans at ¼, mid, and ¾ of kidney length, and averaged. The sinus fat was measured at the renal hilum for both kidneys and averaged. The waist circumference was assessed at the umbilicus. RESULTS: Mean age was 44 years and 70% were female in both groups. The mean ± SD glomerular volume was 0.0010 ± 0.0003 mm3 in the low and 0.0060 ± 0.0011 mm3 in the high group (p <0.001). The table compares fat distribution between these two groups.Table: No Caption available.CONCLUSION: In this pilot study, the proportional increase in visceral obesity with glomerulomegaly was greater than the other indices of obesity. Since contrast computed tomographic imaging is routinely performed during predonation kidney evaluations, visceral fat quantification could potentially be used to better inform the kidney donor selection process.

Liver in the analysis of body composition by dual-energy X-ray absorptiometry.

To investigate the predictive value for hepatic steatosis of a new software for the quantification of visceral fat by dual-energy X-ray absorptiometry (DXA) and to design new regions of interest (ROIs). Adult volunteers were prospectively screened for hepatic steatosis by ultrasonography to obtain a well-balanced population according to the presence/absence of the disease. 90 adult patients without steatosis and 90 with steatosis (mild, 53.3%; moderate, 37.7%; and severe, 10.0%) were recruited. On the same day, all subjects were submitted to blood testing and to anthropometric and whole-body DXA for body composition evaluation. A new software for android visceral fat assessment was employed, and six new "liver-suited" ROIs as well as two modified android ROIs were designed. Their association with steatosis grade was tested by correlation analysis. Fat mass (FM) of the new ROIs showed the highest correlation coefficients with steatosis grade (ρ = 0.610-0.619; p < 0.001), which was also confirmed by multivariate analysis. On the whole population, the new ROIs maintained the highest predictive role for liver steatosis, with areas under the receiver operating characteristic curve up to 0.820 ± 0.032. Inter- and intra-operator agreement for the new ROIs was excellent (k = 0.915-1.000 and k = 0.927-1.000). New ROIs could be designed, standardized and implemented in DXA whole-body scan to provide more specific and predictive values of hepatic lipid content. This is the first study to investigate the predictive value for hepatic steatosis of visceral and regional FM assessed on the hepatic site by DXA in comparison with ultrasonography, anthropometry and surrogate markers derived by previously validated algorithms (fatty liver index).

Mesenteric Fat Is Less among Patients with Complicated Crohnʼs Disease: A Real Association?

Purpose: Mesenteric fat has been associated with more complicated (penetrating and stricturing) disease behaviors among patients with Crohn's disease (CD), suggesting that it is immunologically active. However, this conclusion was based on a cross-sectional analysis with the manual quantification of visceral fat at the level of the umbilicus, which is rather mobile and non-specific. We quantified mesenteric fat at L5-S1, and determined if it was independently associated with complicated CD. Methods: A retrospective study was performed on 176 consecutive CD patients, comparing inflammatory (non-stricturing non-penetrating) with complicated disease (Table). Mesenteric fat was determined at the time of behavior classification. Mesenteric fat was calculated based on CT and CT enterography, using software (TeraRecon, Foster,CA) highlighting the visceral fat by its specific Hounsfield units on a fixed cross sectional level of L5-S1 excluding retroperitoneal, intramuscular, subcutaneous, and intrathecal fat. The association of mesenteric fat with complicated disease behavior was determined after adjustment for disease-specific variables in a logistic regression analysis.TableResults: As expected, patents with complicated disease behavior had a younger age at diagnosis, longer disease duration, and were more likely to have received immunomodulator therapy (Table). There was no difference in mesenteric fat between those with penetrating or stricturing behaviors. Mesenteric fat was significantly lower (92 vs. 66 cm2) among patients with complicated disease. This was confirmed in the multivariate analysis with mesenteric fat negatively associated with complicated disease behavior (p=0.002). Conclusion: Contrary to recent literature, we found that mesenteric fat is negatively associated with complicated (penetrating or stricturing) Crohn's disease. Decreased quantity of mesenteric fat may be important in the development of complicated disease behavior, or, alternatively, may be the result of that behavior. Future prospective studies are necessary to provide measurements prior to the development of penetrating or stricturing complications, to better understand the role of mesenteric fat on the pathogenesis of Crohn's disease.

Ultrasonography is not more reliable than anthropometry for assessing visceral fat in obese children

Visceral fat accumulation is a risk factor for obesity-related complications. Waist circumference is used in clinical practice to assess visceral adiposity. Ultrasound is not superior to waist circumference for assessing visceral obesity in obese children. The optimal site for measuring waist circumference in obese children is at the smallest body circumference between xiphisternum and umbilicus. Visceral fat accumulation is a well-established risk factor for obesity-related complications. In children, it has not been determined whether ultrasonography is superior to waist measurement for assessing visceral fat. Moreover, the optimal site for waist measurement has not been determined. In a prospective cohort of 92 severely obese children and adolescents (age 13.9 ± 2.2 years, body mass index z-score 3.29 ± 0.33), we evaluated the performance of ultrasonography and two different methods of waist circumference measurement, using magnetic resonance imaging as the reference standard. Waist circumference, defined as the smallest body circumference between xiphisternum and umbilicus had the strongest correlation with visceral fat quantity (r = 0.69 all, r = 0.68 girls, r = 0.64 boys). It was not outperformed by ultrasonography (r = 0.60 all, r = 0.62 girls, r = 0.50 boys) and correlated significantly better than the World Health Organization standard for waist measurement, midway between lower margin of the last rib and the crest of the ilium, (r = 0.51 all, r = 0.39 girls, r = 0.46 boys). Waist circumference measurement, defined as the smallest body circumference between xiphisternum and umbilicus, is the preferred non-invasive technique for daily clinical practice to assess visceral fat accumulation in severely obese children and adolescents. There is no place for ultrasonography for the quantification of visceral fat in this group.

Predictors of circulating endothelial progenitor cell levels in patients without known coronary artery disease referred for multidetector computed tomography coronary angiography

Introduction Endothelial progenitor cells (EPCs) have an important role in vascular repair. Levels in peripheral circulation are thought to be related to overall cardiovascular risk and may represent potential therapeutic targets. The aim of this work is to identify predictors of circulating EPC concentrations in patients without known coronary artery disease (CAD). Methods The study population consisted of 215 patients without known CAD referred for multidetector computed tomography (MDCT) coronary angiography (CTA) during a 6-month period. All patients underwent: 1) short anamnesis; 2) anthropometric measurements; 3) blood pressure and heart rate assessment; 4) blood tests; and 5) MDCT (including quantification of visceral fat, quantification of coronary artery calcification [CAC] and CTA). Results The patients’ mean age was 58 ± 11 years (26–84) and 61% were male. Dyslipidemia (59%) and hypertension (57%) were the most prevalent risk factors. Twenty-seven percent met the ATP III criteria for metabolic syndrome. Mean Framingham risk score was 12 ± 9%. Sixty-seven percent had no significant CAD but 64% had some degree of coronary calcification. The mean CAC (Agatston) was 186 ± 433. Mean EPC concentration, expressed as a percentage of total white blood cells, was 0.05 ± 0.08% (0.0–0.58%). EPCs were inversely related to the presence of diabetes mellitus and smoking, and positively related to C-reactive protein. No significant correlations were found between EPCs and other risk factors, measurements of adiposity, atherosclerotic burden or severity of CAD. Conclusion In patients without known CAD referred for MDCT, EPC levels in peripheral blood cannot be significantly estimated or predicted from knowledge of patient anamnesis, risk factors, visceral fat, CAC or CTA.

Predictors of circulating endothelial progenitor cell levels in patients without known coronary artery disease referred for multidetector computed tomography coronary angiography

IntroductionEndothelial progenitor cells (EPCs) have an important role in vascular repair. Levels in peripheral circulation are thought to be related to overall cardiovascular risk and may represent potential therapeutic targets. The aim of this work is to identify predictors of circulating EPC concentrations in patients without known coronary artery disease (CAD). MethodsThe study population consisted of 215 patients without known CAD referred for multidetector computed tomography (MDCT) coronary angiography (CTA) during a 6-month period. All patients underwent: 1) short anamnesis; 2) anthropometric measurements; 3) blood pressure and heart rate assessment; 4) blood tests; and 5) MDCT (including quantification of visceral fat, quantification of coronary artery calcification [CAC] and CTA). ResultsThe patients’ mean age was 58±11 years (26-84) and 61% were male. Dyslipidemia (59%) and hypertension (57%) were the most prevalent risk factors. Twenty-seven percent met the ATP III criteria for metabolic syndrome. Mean Framingham risk score was 12±9%. Sixty-seven percent had no significant CAD but 64% had some degree of coronary calcification. The mean CAC (Agatston) was 186±433.Mean EPC concentration, expressed as a percentage of total white blood cells, was 0.05±0.08% (0.0-0.58%). EPCs were inversely related to the presence of diabetes mellitus and smoking, and positively related to C-reactive protein. No significant correlations were found between EPCs and other risk factors, measurements of adiposity, atherosclerotic burden or severity of CAD. ConclusionIn patients without known CAD referred for MDCT, EPC levels in peripheral blood cannot be significantly estimated or predicted from knowledge of patient anamnesis, risk factors, visceral fat, CAC or CTA.