Does Measurement Site for Visceral and Abdominal Subcutaneous Adipose Tissue Alter Associations With the Metabolic Syndrome?

Abstract

OBJECTIVE -To determine whether the associations between visceral adipose tissue (VAT), abdominal subcutaneous adipose tissue (ASAT), and the metabolic syndrome are altered depending on measurement site for VAT and ASAT and the definition used to identify the metabolic syndrome.RESEARCH DESIGN AND METHODS -Total VAT and ASAT volume was derived using ϳ37 contiguous computed tomography (CT) images from T10 -T11 to L5-S1 in 85 men. CT images obtained at eight intervertebral locations (e.g., L4 -L5, L3-L4, etc.) were used to determine the associations between partial volumes (single images) and metabolic syndrome. Metabolic syndrome was defined using the National Cholesterol Education Program (NCEP) and International Diabetes Federation (IDF) criteria. Logistic regression was used to calculate the odds ratio (OR) per SD increase in adipose tissue.RESULTS -For total and all partial volumes, VAT was more strongly associated with metabolic syndrome than ASAT independent of metabolic syndrome criteria. The OR (per SD) for NCEP metabolic syndrome was higher for total VAT volume (OR ϭ 7.26) and for the partial volumes at T12-L1 (7.46) and L1-L2 (8.77) than those at the L4 -L5 level (3.94). The OR for metabolic syndrome (ϳ2.6) was not substantially different among the ASAT measures. A similar pattern of association was observed using the IDF metabolic syndrome criteria.CONCLUSIONS -The measurement site for VAT, but not for ASAT, has a substantial influence on the magnitude of the association with both metabolic syndrome definitions. However, because VAT remained significantly associated with metabolic syndrome regardless of measurement site, the clinical interpretation was unaltered by measurement protocol or metabolic syndrome definition. Diabetes Care 29:679 -684, 2006M ounting evidence suggests that the metabolic syndrome, generally characterized using the National Cholesterol Education Program (NCEP) criteria, is a powerful predictor of morbidity and mortality (1). Because abdominal obesity is an important component of the NCEP metabolic syndrome definition (2), researchers have investigated the relationship between visceral adipose tissue (VAT) and abdominal subcutaneous adipose tissue (ASAT) with metabolic syndrome (3,4). Carr et al. (3) and Goodpaster et al. (4) report that VAT is associated with an increased incidence of metabolic syndrome. Conversely, ASAT is not consistently reported to be a significant correlate of metabolic syndrome (4) or its individual components (3). This may be due in part to variation in the measurement site selected for quantifying abdominal adipose tissue. Although L4 -L5 is the most commonly used landmark for measuring VAT and ASAT, there is reason to believe that L4 -L5 is not the ideal site for quantifying abdominal adipose tissue or for predicting obesityrelated metabolic risk. Recent studies report that a single image in the upper abdomen (i.e., at L1-L2 or L2-L3) is a more suitable surrogate for total VAT (5-7) and ASAT volume (7) than an image at L4 -L5. If one assumes that the a...

Quantitative comparison and evaluation of software packages for assessment of abdominal adipose tissue distribution by magnetic resonance imaging

“…TAT was calculated by adding SAT and VAT (TAT ¼ SAT þ VAT); therefore, some small intramuscular deposits of adipose tissue were not accounted for. Similar to other published reports, 5,7,18,22,25,29,[33][34][35][36][37][40][41][42][43][44][45]47,[49][50][51][52][53][54][55][56][57][58][59][60][61][62][63] VAT and SAT were not further subdivided.…”

“…Recent studies suggest using single-slice images in the upper abdomen (L1-L3) to minimize scanning and data analysis time and cost. The results show that single images are a good surrogate (Po0.01-o0.05 5,6,[29][30][31][32][33] ) for volume measurements of VAT or TAT.…”

“…[1][2][3][4][5][6][7] Many direct and indirect methods have been used to quantify body fat, such as anthropometric measurements 8 (for example, waist circumference), underwater weighing, 8,9 bioelectric impedance, 10 dual-energy X-ray absorptiometry, 11,12 computed tomography (CT) [13][14][15][16] and magnetic resonance imaging (MRI). However, at present, most published research endorses either CT or MRI as the best in vivo methods for accurate and reliable data about the amount and distribution of abdominal adipose tissue.…”

Automated and reproducible segmentation of visceral and subcutaneous adipose tissue from abdominal MRI

“…The L4-L5 level has been found to contain the largest amount of AT 14,17 and VAT has been found more concentrated and more strongly correlated to health risks at a higher location (L2-L3). [17][18][19][20] However, VAT has been found significantly associated with the metabolic syndrome independent of measurement site. 19 The abdominal subvolume used in this study typically included the volume between 2 cm below the promontorium and the lower part of L2 in the validation cohort.…”

“…[17][18][19][20] However, VAT has been found significantly associated with the metabolic syndrome independent of measurement site. 19 The abdominal subvolume used in this study typically included the volume between 2 cm below the promontorium and the lower part of L2 in the validation cohort. The volume used thus most likely allows robust estimates of the total amounts of SAT and VAT.…”