Estimation of CT-Derived Abdominal Visceral and Subcutaneous Adipose Tissue Depots from Anthropometry in Europeans, South Asians and African Caribbeans

Abstract

BackgroundSouth Asians and African Caribbeans experience more cardiometabolic disease than Europeans. Risk factors include visceral (VAT) and subcutaneous abdominal (SAT) adipose tissue, which vary with ethnicity and are difficult to quantify using anthropometry.ObjectiveWe developed and cross-validated ethnicity and gender-specific equations using anthropometrics to predict VAT and SAT.Design669 Europeans, 514 South Asians and 227 African Caribbeans (70±7 years) underwent anthropometric measurement and abdominal CT scanning. South Asian and African Caribbean participants were first-generation migrants living in London. Prediction equations were derived for CT-measured VAT and SAT using stepwise regression, then cross-validated by comparing actual and predicted means.ResultsSouth Asians had more and African Caribbeans less VAT than Europeans. For basic VAT prediction equations (age and waist circumference), model fit was better in men (R2 range 0.59-0.71) than women (range 0.35-0.59). Expanded equations (+ weight, height, hip and thigh circumference) improved fit for South Asian and African Caribbean women (R2 0.35 to 0.55, and 0.43 to 0.56 respectively). For basic SAT equations, R2 was 0.69-0.77, and for expanded equations it was 0.72-0.86. Cross-validation showed differences between actual and estimated VAT of <7%, and SAT of <8% in all groups, apart from VAT in South Asian women which disagreed by 16%.ConclusionWe provide ethnicity- and gender-specific VAT and SAT prediction equations, derived from a large tri-ethnic sample. Model fit was reasonable for SAT and VAT in men, while basic VAT models should be used cautiously in South Asian and African Caribbean women. These equations will aid studies of mechanisms of cardiometabolic disease in later life, where imaging data are not available.

Anthropometrically‐predicted visceral adipose tissue and mortality among men and women in the third national health and nutrition examination survey (NHANES III)

“…Although waist circumference is often considered an anthropometric proxy for VAT, it cannot differentiate VAT from the less deleterious subcutaneous adipose tissue (SAT) in the abdomen (Despres, 2012; Ibrahim, 2010), and is more closely correlated to total body adipose tissue ( R 2 =0.85) than VAT ( R 2 =0.59) (Bouchard, 2007). Investigators have recently developed equations to predict VAT that simultaneously integrate various anthropometric dimensions such as body mass index (BMI) and circumferences of the waist and thigh to more accurately approximate measured VAT ( R 2 =0.80–0.84) (Eastwood et al, 2013; Neamat-Allah et al, 2014; Samouda et al, 2013). While larger waist circumference is a known predictor of premature mortality (Pischon et al, 2008), the VAT prediction equation has not been studied as a predictor of long-term health outcomes.…”

Body composition in clinical practice

“…Moreover CTCB has been used to derive an predictive cardio-metabolic risk equation, after a large triethnic sample, according to ethnicity-and sex-specific data [23]. This type of evidence endorsed other specific research, analyzing pericardial fat, intrathoracic fat and epicardial fat, showing the potential contribution in CMR stratification [24].…”

Imaging Body Fat

“…These equations will be useful in future studies of mechanisms of cardiometabolic disease across ethnicities in countries where imaging data are not available (figure 4). 21 …”

“…Adipose tissue is dark grey, white line shows delineation of visceral compartment, white arrow indicates depth of subcutaneous compartment. (Reproduced from ref 21)…”