Estudo comparativo de medidas de adiposidade pela absorciometria de dupla-emissão de raios X e pela antropometria

Abstract

The increasing prevalence of overweight / obesity in the world determined the increase in rates of chronic diseases such as diabetes mellitus, hypertension, coronary heart disease, among others. Visceral adipose tissue (VAT) increase is more important than fat excess, so it is necessary to find ways to measure TAV accumulation, to identify people at higher risk of becoming ill. As VAT high precision measurement techniques Nuclear Magnetic Resonance Image, Computed Tomography scan, Dual Energy X-ray Absorptiometry (DXA) are not available to large populations, or for everyday clinical practice, the use of other resources is required. Anthropometric equations for VAT prediction represents a possibility, requiring their suitability to the studied population. The aim of this study was to identify, using anthropometric variables measured in the Pro-Health Study, those that best reflect the accumulation of visceral fat measured by DXA. It was a cross-sectional study with part of a cohort of university employees in Rio de Janeiro - the Pro-Health Study (n = 516; age = 53 (11.0) years), 250 men and 266 women. Two strategies to generate the equations were used: first, based on very strong/strong correlation of anthropometric variables with variables obtained with VAT measured by DXA; second, variables considered fulfilling specific criteria. The values of body mass index (BMI) identified the prevalence of overweight / obesity 71.45% in the sample of the Pro-Health Study, and these higher values when measured by fat mass index (79.4%). predictive equations for the entire sample were generated following the two strategies, and equations for men and women. Predictive equations were also generated for trunk fat mass due to the higher number of correlations with anthropometric variables that VAT, and fat mass index considering that it better reflects body fatness than BMI, identified by the higher prevalence of overweight / obesity when compared to that provided by BMI. Bland-Altman graphical analysis of agreement was used to compare the data estimated by equations with that measured by DXA. The good agreement between the estimated and observed endorsed the use of prediction equations based on anthropometric variables as a useful tool for use in clinical practice in the measurement of visceral fat, trunk fat mass and fat mass index. It was identified a variable little studied so far, the central adiposity index, as capable of measuring VAT, being necessary to study their suitability for other groups. It is recommended, in addition to the study, the routine adoption of dissemination of data related to body composition in all bone densitometry, as a way to increase the power of early diagnosis of changes in the distribution of body fat able to increase the risk of illness