Estimation of CT-derived abdominal visceral and subcutaneous adipose tissue depots from anthropometry in Europeans, South Asians and African Caribbeans

Background South 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. Objective We developed and cross-validated ethnicity and gender-specific equations using anthropometrics to predict VAT and SAT. Design 669 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. Results South 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%. Conclusion We 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

Utilização de medidas antropométricas para a avaliação do acúmulo de gordura visceral The use of anthropometric measures to assess visceral fat accumulation

A obesidade visceral tem sido associada ao desenvolvimento de doenças cardiovasculares e a alguns tipos de câncer. Nesse sentido, é crescente o interesse na avaliação da adiposidade intra-abdominal, de forma a se analisarem o risco de doenças e alterações metabólicas, como intolerância à glicose, hiperinsulinemia, diabetes mellitus tipo 2, dislipidemias e hipertensão arterial. Técnicas de imagem, como a tomografia computadorizada e a ressonância magnética, permitem a mensuração acurada e precisa da gordura visceral..Contudo, ambas são dispendiosas e inaplicáveis na prática clínica de rotina e nos estudos epidemiológicos..Parâmetros antro-pométricos surgem como uma opção para a avaliação da gordura visceral nessas situações, por serem inócuos, de fácil aplicação e de baixo custo. À luz dessas questões, este trabalho objetivou analisar criticamente estudos que avaliaram a pertinência em empregar parâmetros antropométricos como indicadores da gordura visceral. Realizou-se um levantamento bibliográfico, no qual foram consultados periódicos nacionais e internacionais disponíveis nas seguintes bases científicas: Portal de periódicos da Coordenação de Aperfeiçoamento de Pessoal de Nível Superior, Scientific Electronic Library Online, Science Direct e Pubmed, abrangendo publicações entre os anos de 1947 e 2007. Procurou-se dar ênfase aos parâmetros antropométricos, como o índice de massa corporal, a circunferência da cintura, a relação cintura-quadril e o diâmetro abdominal sagital.<br>Visceral obesity has been associated with the development of cardiovascular diseases and some types of cancer. Therefore, there is an increasing interest in quantifying intra-abdominal adiposity in order to assess the risk of metabolic disorders, such as glucose intolerance, hyperinsulinemia, type 2 diabetes, dyslipidemia and hypertension. Imaging techniques such as computed tomography and magnetic resonance provide an accurate and precise measurement of visceral fat. However, both are costly and inapplicable in routine clinical practice and epidemiological studies. Anthropometric parameters are an option for visceral fat assessment in these situations, since they are innocuous, easy to use and inexpensive. In this context, this work aimed to critically analyze studies that assessed anthropometric parameters as indicators of visceral fat. A bibliographic review of domestic and international articles found in the databases Coordenação de Aperfeiçoamento de Pessoal de Nível Superior, Scientific Electronic Library Online, Science Direct and Pubmed, published from 1947 to 2007 was done. Emphasis was given to anthropometric parameters, such as body mass index, waist circumference, waist-to-hip ratio and sagittal abdominal diameter