Estimation Of Visceral Adipose Tissue Research Articles

Standardization of dual-energy x-ray visceral adipose tissue measures for comparison across clinical imaging systems.

Excess visceral adipose tissue (VAT) is a major risk factor for metabolic syndrome (MetS) and clinical guidelines have been proposed to define VAT levels associated with increased risk. The aim was to standardize VAT measures between two dual-energy x-ray absorptiometry (DXA) manufacturers who provide different VAT estimates to support standardization of measures across imaging modalities. Scans from 114 individuals (ages 18-81 years) on GE HealthCare (GEHC) and Hologic DXA systems were compared via Deming regression to standardize VAT between the two systems, validated in a separate sample (n = 15), with κ statistics to assess agreement of VAT measurements for classifying patients into risk categories. The GEHC and Hologic VAT measures were highly correlated and validated in the separate data set (r2 = 0.97). VAT area measures substantially agreed for metabolic risk classification (weighted κ = 0.76) with no significant differences in the population mean values. VAT measures can be estimated from GEHC and Hologic scans that classify individuals in a substantially similar way into metabolic risk categories, and systematic bias between the measures can be removed using simple regression equations. These findings allow for DXA VAT measures to be used in complement to other imaging modalities, regardless of whether scans used GEHC or Hologic systems.

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.

Associations between visceral adipose tissue estimates produced by near-infrared spectroscopy, mobile anthropometrics, and traditional body composition assessments and estimates derived from dual-energy X-ray absorptiometry.

Assessments of visceral adipose tissue (VAT) are critical in preventing metabolic disorders; however, there are limited measurement methods that are accurate and accessible for VAT. The purpose of this cross-sectional study was to evaluate the association between VAT estimates from consumer-grade devices and traditional anthropometrics and VAT and subcutaneous adipose tissue (SAT) from dual-energy X-ray absorptiometry (DXA). Data were collected from 182 participants (female = 114; White = 127; Black/African-American (BAA) = 48) which included anthropometrics and indices of VAT produced by near-infrared reactance spectroscopy (NIRS), visual body composition (VBC) and multifrequency BIA (MFBIA). VAT and SAT were collected using DXA. Bivariate and partial correlations were calculated between DXAVAT and DXASAT and other VAT estimates. All VAT indices had positive moderate-strong correlations with VAT (all P < 0·001) and SAT (all P < 0·001). Only waist:hip (r = 0·69), VATVBC (r = 0·84), and VATMFBIA (r = 0·86) had stronger associations with VAT than SAT (P < 0·001). Partial associations between VATVBC and VATMFBIA were only stronger for VAT than SAT in White participants (r = 0·67, P < 0·001) but not female, male, or BAA participants individually. Partial correlations for waist:hip were stronger for VAT than SAT, but only for male (r = 0·40, P < 0·010) or White participants (r = 0·48, P < 0·001). NIRS was amongst the weakest predictors of VAT which was highest in male participants (r = 0·39, P < 0·010) but non-existent in BAA participants (r = -0·02, P > 0·050) after adjusting for SAT. Both anthropometric and consumer-grade VAT indices are consistently better predictors of SAT than VAT. These data highlight the need for a standardised, but convenient, VAT estimation protocol that can account for the relationship between SAT and VAT that differs by sex/race.

Use of Dual-Energy X-ray Absorptiometry for Body Composition in Chronic Disease Management

Aging and chronic disease are often accompanied by changes in body composition that lead to decreased muscle mass and increased fat mass, even in weight-stable individuals. Both obesity and sarcopenia are important causes of frailty, disability, morbidity, and mortality. Diminished skeletal muscle and expanded visceral fat can act synergistically, which might maximize their effects on physical impairments and metabolic disorders. Dual-energy X-ray absorptiometry (DEXA) was regarded as one of the most versatile imaging techniques for evaluation of sarcopenia and obesity as well as osteoporosis. Whole-body DEXA allows total and regional assessment of the three compartments for fat mass, non-bone lean mass, and bone mineral content. Moreover, DEXA is accurate, reproducible, fast, relatively inexpensive, and involves very low radiation dose to the patient. Developments in DEXA equipment and software allow an accurate and differential estimate of visceral adipose tissue. This review summarizes the clinical practical application of whole-body DEXA values, with use of muscle and fat mass indices in the diagnostic workup of low muscle mass, sarcopenia, and sarcopenic obesity according to the most recent studies and guidelines.

Role of Ultrasonography Compared to Computed Tomography in Measurement of Visceral Adipose Tissue and Subcutaneous Adipose Tissue in Diabetic Overweight and Obese Adolescents

Background: Ultrasound is considered as a suitable, accurate, safe, available technique to measure abdominal adipose tissue of low cost compared to other imaging modalities as CT and MRI. It is superior to BMI as a monitor for diabesity because of it is ability to differentiate between visceral adipose tissue (VAT) and subcutaneous adipose tissue (SAT) in wide epidemiological studies.&#x0D; Results: The correlation between the ultrasound and CT measurements was high with correlation coefficient 0.921 and 0.988 for VAT and SAT respectively. Also there was high significant correlation between the BMI and US and CT measurements of VAT and SAT in all studied groups with correlation coefficient ranging from 0.514 to 0.956.&#x0D; Conclusion: Ultrasound provides reproducible and valid estimates of VAT and SAT and represents a useful method to assess abdominal fat in large scale epidemiological studies.

Validity of dual-energy x-ray absorptiometry for estimation of visceral adipose tissue and visceral adipose tissue change after surgery-induced weight loss in women with severe obesity.

Reliable and simple methods to quantify visceral adipose tissue (VAT) and VAT changes are needed. This study investigated the validity of dual-energy x-ray absorptiometry (DXA) compared with magnetic resonance imaging (MRI) for estimating VAT cross sectionally and longitudinally after surgery-induced weight loss in women with severe obesity. Women with obesity (n = 36; mean age 43 [SD 10] years; 89% White) with DXA and MRI before bariatric surgery (T0) at 12 (T12) and 24 months (T24) post surgery were included. CoreScan (GE Healthcare, Chicago, Illinois) estimated VAT from 20% of the distance between the top of the iliac crest and the base of the skull. MRI VAT (total VAT) was measured from the base of the heart to the sacrum/coccyx on a whole-body scan. Mean DXA VAT was 45% of MRI VAT at T0, 46% at T12, and 68% at T24. DXA underestimated change in MRI VAT between T0 and T12 by 26.1% (0.81 kg, p = 0.03) and by 71.7% (0.43 kg, p < 0.001) between T12 and T24. The relationship between DXA VAT and MRI VAT differed between T12 and T24 (p value for interaction = 0.03). CoreScan lacks validity for comparing VAT across individuals or for estimating the size of changes within individuals; however, within the limits of measurement error, it may provide a useful indicator of whether some VAT change has occurred within an individual.

Evaluation of the Value of Waist Circumference and Metabolomics in the Estimation of Visceral Adipose Tissue.

Visceral adipose tissue (VAT) is a strong prognostic factor for cardiovascular disease and a potential target for cardiovascular risk stratification. Because VAT is difficult to measure in clinical practice, we estimated prediction models with predictors routinely measured in general practice and VAT as outcome using ridge regression in 2,501 middle-aged participants from the Netherlands Epidemiology of Obesity study, 2008–2012. Adding waist circumference and other anthropometric measurements on top of the routinely measured variables improved the optimism-adjusted R2 from 0.50 to 0.58 with a decrease in the root-mean-square error (RMSE) from 45.6 to 41.5 cm2 and with overall good calibration. Further addition of predominantly lipoprotein-related metabolites from the Nightingale platform did not improve the optimism-corrected R2 and RMSE. The models were externally validated in 370 participants from the Prospective Investigation of Vasculature in Uppsala Seniors (PIVUS, 2006–2009) and 1,901 participants from the Multi-Ethnic Study of Atherosclerosis (MESA, 2000–2007). Performance was comparable to the development setting in PIVUS (R2 = 0.63, RMSE = 42.4 cm2, calibration slope = 0.94) but lower in MESA (R2 = 0.44, RMSE = 60.7 cm2, calibration slope = 0.75). Our findings indicate that the estimation of VAT with routine clinical measurements can be substantially improved by incorporating waist circumference but not by metabolite measurements.

The site of waist measurement impacts the estimation of visceral fat: results from three-dimensional photonic body scanning.

Currently, various protocols regarding the site of waist circumference (WC) measurement are in place. This study aimed to analyse the effect of the site of WC measurement on visceral adipose tissue (VAT) estimation. WC was obtained at 7 anatomical sites in 211 German volunteers (103 males) aged 23-81 years using three-dimensional photonic body scanning (PBS). At one site, WC was additionally measured by tape. The quantity of VAT was assessed by MRI. Models to estimate VAT based on WC were developed; the precision of the estimation is represented by R2. The influence of the applied method of WC assessment (tape v. PBS) on the estimations is reported. Results show that the amount of estimated VAT and the precision of VAT estimation were dependent on the site of measurement. VAT was estimated most precisely by WC taken at the level of the lowest rib (WCrib: R2 = 0·75 females; 0·79 males), the minimum circumference (WCmin: R2 = 0·75 females; 0·77 males) and at the narrowest part of the torso (WCnar: R2 = 0·76 females; 0·77 males), and least precisely by WC assessed at the top of iliac crest (WCiliac: R2 = 0·61 females; 0·60 males). VAT estimates based on WC obtained by PBS were smaller and estimations were slightly less precise compared to estimates based on tape measures. Our results indicate that the method and the site of waist measurement should be considered when estimating VAT based on WC. The implementation of a standardised protocol using either WCrib, WCmin or WCnar could improve the precision of VAT estimation.

Precision of Lunar Dual-energy X-ray Absorptiometry (iDXA) in measuring body composition among colorectal cancer patients and healthy subjects.

High quality and precise methods are needed when monitoring changes in body composition among colorectal cancer (CRC) patients and healthy subjects. The aim of this study was to estimate precision of the Dual-energy X-ray absorptiometry (Lunar iDXA, GE Healthcare software enCORE version 16) in measuring body composition in CRC patients and healthy subjects. Precision error of iDXA in measuring body composition was investigated in the current study. Thirty CRC patients and 30 healthy subjects, including both men and women underwent two consecutive whole-body DXA scan with repositioning. Precision estimates of visceral adipose tissue (VAT) and subcutaneousadipose tissue (SAT) in the abdominal region, and total fat mass (FM), fat-free mass (FFM), lean mass (LM), bone mineral density (BMD) and bone mineral content (BMC) were calculated. Precision error expressed as coefficient of variation (% CV) of VAT and SAT were estimated to be 3.56% and 3.28% among CRC patients, and 5.30% and 3.46% among healthy subjects. Estimated precision errors for body masses in the total region ranged between 0.49-1.01% and 0.40-0.88% in CRC patients and healthy subjects, respectively. Least significant change (LSC) in VAT mass, SAT mass, FM and LM were 140.9g, 121.4g, 637.0g and 701.0g, respectively, among CRC patients. Among healthy subjects the LSC in VAT, SAT, FM and LM were 80.93g, 98.90g, 484.0g and 618.0g, respectively. Only minor and non-significant differences between the two consecutive measurements for each body compartment were observed within both populations, and we found no systematic bias in the distribution of the differences. The Lunar iDXA demonstrated high precision in body composition measurements among both CRC patients and healthy subjects. Hence, iDXA is a useful tool in clinical following-up and interventions targeted towards changes in body composition.

MRI Based Validation of Abdominal Adipose Tissue Measurements From DXA in Postmenopausal Women

Visceral adipose tissue (VAT) is a hypothesized driver of chronic disease. Dual-energy X-ray absorptiometry (DXA) potentially offers a lower cost and more available alternative compared to gold-standard magnetic resonance imaging (MRI) for quantification of abdominal fat sub-compartments, VAT and subcutaneous adipose tissue (SAT). We sought to validate VAT and SAT area (cm2) from historical DXA scans against MRI. Participants (n = 69) from the Women's Health Initiative (WHI) completed a 3 T MRI scan and a whole body DXA scan (Hologic QDR2000 or QDR4500; 2004-2005). A subset of 43 participants were scanned on both DXA devices. DXA-derived VAT and SAT at the 4th lumbar vertebrae (5 cm wide) were analyzed using APEX software (v4.0, Hologic, Inc., Marlborough, MA). MRI VAT and SAT areas for the corresponding DXA region of interest were quantified using sliceOmatic software (v5.0, Tomovision, Magog, Canada). Pearson correlations between MRI and DXA-derived VAT and SAT were computed, and a Bland-Altman analysis was performed. Participants were primarily non-Hispanic white (86%) with a mean age of 70.51 ± 5.79 years and a mean BMI of 27.33 ± 5.40 kg/m2. Correlations between MRI and DXA measured VAT and SAT were 0.90 and 0.92, respectively (p ≤ 0.001). Bland-Altman plots showed that DXA-VAT slightly overestimated VAT on the QDR4500 (-3.31 cm2); this bias was greater in the smaller subset measured on the older DXA model (QDR2000; -30.71 cm2). The overestimation of DXA-SAT was large (-85.16 to -118.66 cm2), but differences were relatively uniform for the QDR4500. New software applied to historic Hologic DXA scans provide estimates of VAT and SAT that are well-correlated with criterion MRI among postmenopausal women.

DEVELOPMENT AND VALIDATION OF EQUATIONS TO ESTIMATE VISCERAL ADIPOSE TISSUE IN MILITARY MEN

ABSTRACT Introduction It has been suggested that visceral adipose tissue (VAT) is associated with several non-communicable chronic diseases, but measuring it is difficult. Thus, anthropometry could be used because is easily applied in clinical practice. Objectives The present study aimed to develop and validate VAT estimation equations (Eq) in military men. Methods The sample consisted of 409 (mean age, 36.5 ± 6.7 years) military men in the Brazilian Army (BA) divided into an equation group (EG) ( n = 270; mean age, 37.0 ± 6.3 years) and a validation group (VG) ( n =139; mean age, 36.0 ± 7.2 years). Anthropometric, hemodynamic and DXA body composition evaluations ( GE iLunar ) were performed. The Student’s t test, Pearson’s correlation, and stepwise general linear regression were applied. Bland-Altman graphics were used to assess the concordance between VAT by Eq and by DXA. The level of significance was 95% ( p &lt; 0.05). Results Age, waist circumference (WC), hip circumference and body mass index presented the main significant positive correlations with the VAT-DXA. Four Eq were created Eq1 ( r 2 = 0.793), Eq2 ( r 2 = 0.810), Eq3 ( r 2 = 0.817), and Eq 4 ( r 2 = 0.823) ( p &lt; 0.05). No differences were observed between VAT by DXA and VAT by Eq ( p = 0.982, p = 0.970, p = 0.495 and p = 0.698). Bland-Altman analysis also presented good concordance as the bias was close to zero and was not statistically significant. Conclusion Eq2 (age*13.0 + WC*60.0 - 4975,.5) was more suitable because it is easier to apply, has a higher predictive power (81.0%), less bias (1.86) and validation yielded average VAT values close to those found in DXA. It may still be considered a valuable tool for other extensive epidemiological studies in military men in the BA and can be used in adult men. Evidence Level I: Development of diagnostic criteria on consecutive patients (with universally applied reference ‘‘gold’’ standard).

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

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. 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). 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. 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 (β 0.14 units; 95% CI 0.08, 0.20), higher log high-sensitivity C-reactive protein (β 0.51 mg/L; 0.36, 0.66) and log leptin (β 0.36 ng/mL; 0.27, 0.44), and lower log adiponectin (β -0.08 ug/mL; -0.13, -0.02). SAAT and TAAT showed similar associations as VAT with comparable or greater effect sizes. 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.

Estimation Of Visceral Adipose Tissue: A Device Comparison

Many body composition devices now provide an estimate of visceral adipose tissue (VAT), a significant risk factor for cardiometabolic disease. PURPOSE: to evaluate the relationship between estimates of VAT from bioelectrical impedance (BIA), ultrasound (US), and dual-energy x-ray absorptiometry (DXA). METHODS: VAT was estimated in 124 adults (66% Female; Mean ± SD: Age: 25.4±8.9 yrs; BMI: 25.4±5.5 kg·m-2; %BF: 29.7±10.5%). VAT area (cm2) was estimated from a BIA system specific algorithm. VAT thickness (cm) was estimated using US, quantified as the distance between the linea alba and aorta. VAT volume (cm3) was estimated from the DXA predefined android region. Linear regression was used to evaluate the relationship between estimates and to identify factors that may contribute to estimate differences in the entire group and by sex. RESULTS: In the full group, VAT estimates from all three methods were significantly correlated [BIA-DXA (R=0.768; R2=0.589); BIA-US (R=0.545; R2=0.297); DXA-US (R=0.785; R2=0.616) (p<0.001)]. In men, stronger relationships were observed with DXA [BIA-DXA (R=0.852; R2=0.727); BIA-US (R=0.774; R2=0.600); DXA-US (R=0.878; R2=0.772) (p<0.001)]; in women, weaker relationships were observed with US [BIA-DXA (R=0.890; R2=0.793); BIA-US (R=0.567; R2=0.321); DXA-US (R=0.690; R2=0.477) (p<0.001)]. In men, total body water (TBW) explained 31.9% and 12.0% of the variance in the difference between BIA-DXA and BIA-US, respectively; %BF explained 13.1% of the variance in the difference between DXA-US (all p<0.05). In women, %BF explained 28.9%, 34.0%, and 15.6% of the variance in the difference between BIA-DXA, BIA-US, and DXA-US, respectively (all p<0.001). CONCLUSIONS: BIA and US are cost-effective alternatives to DXA. BIA may provide a more comparable estimate to DXA, while greater variability may occur when comparing with US, especially in women. Differences between estimates may be influenced by TBW and %BF.

DXA Measured Visceral Adipose Tissue, Total Fat, Anthropometric Indices and its Association With Cardiometabolic Risk Factors in Mother-Daughter Pairs From India

Visceral fat is the pathogenic fat depot associated with diabetes, dyslipidemia, and cardiovascular diseases. Estimation of visceral adipose tissue (VAT) by dual energy-X-ray absorptiometry (DXA) is a newer technique with less radiation exposure, shorter scanning time, and lower cost. In this study, we attempted to look at relationship between cardiometabolic risk factors and VAT, total body fat percent (TBF%) and anthropometry. We also studied the changes in body composition and metabolic parameters with menopause. The familial resemblance of VAT and TBF% in mother-daughter pair was also compared. This was a cross sectional community study of 300 women (150 postmenopausal mothers and 150 premenopausal daughters). Body composition indices by DXA and metabolic parameters were assessed. The association between DXA-VAT, TBF%, anthropometric measures, and cardiometabolic risk factors were studied by correlation, receiver operating characteristics curves, and logistic regression analysis. VAT indices were significantly higher and lean indices lower in postmenopausal women as compared to premenopausal women. One fourth of postmenopausal women were categorized as metabolically obese normal weight. DXA-VAT was a better predictor of cardiometabolic risk factors as compared to waist circumference, body mass index, and TF% in postmenopausal women (AUC:0.68 vs 0.62, 0.60 & 0.5, respectively), whereas body mass index had a better prediction in premenopausal women(AUC:0.68). VAT area >100 cm² had a significant association with the presence of ≥2 cardiometabolic risk factors (p = 0.04, OR: 2.2, CI:1.0–4.7) in the postmenopausal women. Daughters of the mothers with higher TBF% were found to have a higher TBF% compared to daughters of mothers with normal TBF% (36.2 ± 4.2 vs 32.2 ± 4.4, p = 0.03), similar resemblance was not seen for VAT. The study showed that the VAT increases and lean mass decreases with age and menopause. DXA measured VAT is a better predictor of cardiometabolic risk in postmenopausal women but not in premenopausal women. Total body fat may have a familial resemblance, but not the VAT which is determined by age, menopause, and probable life style factors.

Added values of DXA-derived visceral adipose tissue to discriminate cardiometabolic risks in pre-pubertal children.

BackgroundThe new generation of dual energy X-ray absorptiometry (DXA) scanners provide visceral adipose tissue (VAT) estimates by applying different algorithms to the conventional DXA-derived fat parameters such as total fat, trunk fat and android fat for the same image data.ObjectiveThis cross-sectional study aimed to investigate whether VAT estimates from Hologic scanners are better predictors of VAT than conventional DXA parameters in pre-pubertal children, and to explore the discrimination ability of these VAT methods for cardiometabolic risks.MethodsHealthy pre-pubertal children aged 7–10 years were recruited for basic anthropometric, DXA and magnetic resonance imaging (MRI) measurements. Laboratory tests included lipid profile, glycaemic tests and blood pressure.ResultsAll VAT methods had acceptable to excellent performance for the diagnosis of dyslipidaemia (area under the curve [AUC] = 0.753–0.837) and hypertensive risk (AUC = 0.710–0.821) in boys, but suboptimal performance for these risks in girls, except for VAT by MRI in the diagnosis of dyslipidaemia. In both sexes, all VAT methods had no or poor discrimination ability for diabetes risk.ConclusionsDXA-derived VAT estimates are very highly correlated with standard methods but has equivalent discrimination abilities compared to the existing DXA-derived fat estimates.

The combination of insulin resistance and visceral adipose tissue estimation improves the performance of metabolic syndrome as a predictor of type 2 diabetes.

To assess the performance of metabolic syndrome as a predictor of type 2 diabetes in a model that also includes both a measure of insulin resistance and a metabolic score for visceral fat, and to propose a novel metabolic syndrome definition. In a prospective Metabolic Syndrome Cohort (n=6143), we evaluated improvements in type 2 diabetes risk prediction using International Diabetes Federation-defined and Adult Treatment Panel III-defined metabolic syndrome, after inclusion in the model of updated homeostatic model assessment of insulin resistance and a metabolic score for visceral fat. We also developed a modified metabolic syndrome construct, 'MS-METS', which used the metabolic score for visceral fat instead of waist circumference to evaluate improved predictive performance for risk of developing type 2 diabetes. Participants who had metabolic syndrome as defined by both the Adult Treatment Panel III and the International Diabetes Federation criteria had a higher risk of type 2 diabetes compared to participants who did not meet these criteria. Addition of updated homeostatic model assessment of insulin resistance and metabolic score for visceral fat to both metabolic syndrome definitions increased predictive performance for type 2 diabetes risk. Homeostatic model assessment of insulin resistance was the only additional predictor of type 2 diabetes in participants without metabolic syndrome. Conversely, in participants with metabolic syndrome, the use of the metabolic score for visceral fat was the stronger added predictor for type 2 diabetes. When evaluating participants using the MS-METS definition we observed the largest improvement in predictive ability for type 2 diabetes risk and a significant reduction in risk overestimation compared to evaluation using metabolic syndrome defined according to the International Diabetes Federation and Adult Treatment Panel III criteria alone. Inclusion of updated homeostatic model assessment of insulin resistance and metabolic score for visceral fat increases performance of metabolic syndrome in prediction of type 2 diabetes. Assessment of insulin resistance could be more useful than conventional metabolic syndrome and assessment of visceral adipose tissue could be more useful in people with metabolic syndrome. Metabolic syndrome as defined using our modified MS-METS construct improved the accuracy of type 2 diabetes prediction.

Visceral Adiposity Index as an Independent Marker of Subclinical Atherosclerosis in Individuals Prone to Diabetes Mellitus.

Aims: The visceral adiposity index (VAI) has been proposed as an estimate of visceral adipose tissue (VAT) mass and as an indicator of VAT dysfunction. Both parameters are associated with cardiometabolic risk, including insulin resistance. In this study, we investigated whether VAI is associated with subclinical atherosclerosis in subjects who were free of cardiovascular disease but were at risk of developing diabetes mellitus.Methods: A total of 731 adults with a median age of 47 years old without diabetes mellitus were included in this cross-sectional study. The anthropometric data, blood pressure, and lipid profiles of 398 women and 333 men were measured. All subjects underwent an oral glucose tolerance test, and carotid intima–media thickness (cIMT) was evaluated by ultrasound. Insulin resistance was estimated using the homeostatic model assessment of insulin resistance (HOMA-IR).Results: VAI and HOMA-IR (βst = 0.44, p < 0.0001), VAI and cIMT (βst = 0.17, p < 0.0001), and HOMA-IR and cIMT (βst = 0.09, p = 0.0127) were correlated with each other. After adjusting for cofounding variables, VAI is still correlated with HOMA-IR (βst = 0.42, p < 0.0001). Furthermore, VAI (βst = 0.07, p = 0.0392) but not HOMA-IR (βst = 0.03, p = 0.37) was correlated with cIMT independently of other established cardiovascular risk factors.Conclusion: The calculation of VAI may provide a better estimation of subclinical atherosclerosis than the calculation of HOMA-IR.

Dual-Energy X-Ray Absorptiometry Compared to Computed Tomography for Visceral Adiposity Assessment Among Gastrointestinal and Pancreatic Cancer Survivors

Dual-energy x-ray absorptiometry (DXA) for visceral adipose tissue (VAT) assessment is used as an alternative to computed tomography (CT) for research purposes in apparently healthy and clinical populations. It is unknown whether DXA is comparable to CT among cancer survivors, especially in cases where VAT assessment may be affected by treatment history and side effects and become more challenging to assess, such as a history of surgical gastrointestinal resection and/or ascites. The purpose of this study was to determine the level of agreement between DXA and CT when assessing VAT area and volume among cancer survivors. One hundred Gastrointestinal and pancreatic cancer survivors underwent abdominal and pelvis CT and whole-body DXA within 48 hours. Bland-Altman analysis revealed that in women and men, DXA VAT-area estimates were larger and smaller, respectively, and was consistently smaller in estimates for VAT-volume. Correlations from linear regression analysis revealed statistically significant positive correlations between measurement methods. Overall, while DXA VAT estimates are highly correlated with CT VAT estimates, DXA estimates show substantial bias which indicates the two methods are not interchangeable in this population. Further research is warranted with a larger, more homogeneous sample to develop better estimates of the bias.

Does Intermittent Energy Restriction Plus Mediterranean Diet Reduce Visceral Adipose Tissue and Minimize Adaptive Responses of Energy Restriction? A Randomized Pilot Study (P21-016-19)

Abstract Objectives Test if an intermittent energy restriction with a Mediterranean diet (IER + MED) preferentially promotes loss of visceral adipose tissue (VAT) over subcutaneous adipose tissue (SAT), with minimal changes to resting energy expenditure (REE) and physical activity level (PAL), compared to an active control, the Dietary Approaches to Stop Hypertension (DASH) diet, in an East Asian adult population. Methods Men and women in Hawai'i (n = 60, aged 35–55, BMI 25–40, VAT ≥ 90cm2 for men and ≥ 80cm2 for women) of East Asian origin, were randomized equally to IER + MED (2 days with 70% energy restriction and 5 days euenergetic MED) or a 7 day euenergetic DASH diet for 12 weeks. Dual energy X-ray absorptiometry (DXA) for estimation of VAT and abdominal SAT, REE through indirect calorimetry, and physical activity questionnaires were collected at baseline and week 12. Four-days mobile food records were completed at baseline, weeks 5–6 and 11. Results At week 12, participants in the IER + MED group lost greater amounts of VAT (−22.6 ± 3.6 cm2 vs. −10.7 ± 3.5 cm2 in DASH, P = 0.022) and SAT (−48.2 ± 6.4 cm2 vs. −15.0 ± 6.1 cm2 in DASH, P &lt; 0.001). The IER + MED diet did not preferentially promote loss of VAT over SAT compared to DASH. Changes in VAT: SAT were 0.01 ± 0.01 for both groups (IER + MED vs. DASH, P = 0.825). Mean daily energy intake reductions at week 11 were larger in IER + MED (27%) than DASH (16%); and mean loss of weight at week 12 was higher in the IER + MED group (−5.9 ± 0.7 kg vs. −3.3 ± 0.6 kg in DASH, P = 0.007). Despite the significant drop in energy and weight for IER + MED, there was a non-significant change in REE of −105 ± 56 kcal/day for IER + MED (P = 0.068) and −25 ± 57 kcal/day for DASH (P = 0.663). Hours of moderate-to-vigorous physical activity per day were 1.6 ± 0.2 for IER + MED and 1.4 ± 0.3 for DASH at baseline and did not change significantly over 12 weeks. Conclusions In this short-term pilot study, the IER + MED diet was more effective at reducing VAT, SAT and weight; however, it did not preferentially promote loss of VAT over SAT, as compared to the active control DASH group. Loss of VAT, SAT and weight from the IER + MED diet may be sustainable long term as REE and PAL, which commonly decrease with large energy restriction, did not significantly change over 12 weeks. Funding Sources The William &amp; Ellen Melohn Endowed Research Fund, University of Hawaii; National Institutes of Health, National Cancer Institute.

Adiposity Mediates the Association between the Dietary Inflammatory Index and Markers of Type 2 Diabetes Risk in Middle-Aged Black South African Women.

The dietary inflammatory index (DII®), a validated tool used to measure the inflammatory potential of the diet, has been associated with metabolic disorders in various settings, but not in African populations. The aim of this study was to investigate whether the DII is associated with markers of type 2 diabetes (T2D) risk, and if this association is mediated by adiposity and/or low-grade inflammation, in black South Africa women. Energy-adjusted-DII (E-DII) scores were calculated in 190 women (median age, 53 years) from the Birth-to-Twenty plus cohort using a validated food frequency questionnaire. Fasting glucose, insulin, HbA1c, and inflammatory cytokines were measured, and an oral glucose tolerance test performed. Basic anthropometry and dual-energy x-ray absorptiometry-derived body fat, including estimate of visceral adipose tissue (VAT) area, were measured. E-DII scores were associated with all markers of T2D risk, namely, fasting glucose and insulin, HbA1c, HOMA2-IR, two-hour glucose and Matsuda index (all p < 0.05). After adjusting for age, measures of adiposity, but not inflammatory cytokines, mediated the association between E-DII and markers of T2D risk (p < 0.05). Measures of central obesity had proportionally higher (range: 23.5–100%) mediation effects than total obesity (range: 10–60%). The E-DII is associated with T2D risk through obesity, in particular central obesity, among black middle-aged South African women.