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

Anthropometric measures, predicted visceral adipose tissue and biomarkers of chronic inflammation

BACKGROUND

Evidence has linked low-grade systemic inflammation and visceral adipose tissue (VAT) with development of chronic conditions. Cytokines and select proteins released by VAT may promote a low-grade inflammatory response. A number of equations have been developed to estimate VAT levels. In this study, we compared predicted VAT equation relationships with biomarkers of inflammation.

METHODS

This was a cross-sectional study of 2038 men and women aged 46-73 years. Correlation and linear regression analyses were performed to examine inflammatory biomarker relationships with four commonly assessed anthropometric measures and 10 predicted VAT equations.

RESULTS

Compared with anthropometric measures, predicted VAT equations were found to explain a greater proportion of variance in CRP (R2  = .075, p = .001), IL-6 (R2  = .060, p = .001), TNF-α (R2  = .017, p = .005), resistin (R2  = .011, p = .012), monocyte (R2  = .027, p = .001), eosinophil (R2  = .012, p = .01) and basophil (R2  = .015, p = .002) levels in males, and a greater variance in concentrations of C3 (R2  = .175, p = .001), IL-6 (R2  = .090, p = .001), TNF-α (R2  = .036, p = .001), adiponectin (R2  = .121, p = .001), the adiponectin-to-leptin ratio (R2  = .444, p = .001), resistin (R2  = .025, p = .001), white blood cell count (R2  = .057, p = .001), neutrophils (R2  = .061, p = .001) and lymphocytes (R2  = .020, p = .001) in females.

CONCLUSION

Equations for assessing VAT levels might be useful to characterise metabolic health. Further studies that examine predicted VAT relationships with disease and mortality outcomes are warranted.

The Visceral Adiposity Index Is a Better Predictor of Excess Visceral Fat in Military Pilots: A Cross-sectional Observational Study

INTRODUCTION

Visceral adipose tissue (VAT) is related to cardiometabolic risk. Estimating it using the visceral adiposity index (VAI) could identify this risk in the Brazilian Air Force (BAF) aviator population. The aim here is to verify the predictive capacity of the VAI for identifying visceral fat areas compared to traditional obesity indicators in BAF pilots.

MATERIALS AND METHODS

Forty male BAF pilots were recruited. The study was conducted in two stages: the first applied a structured questionnaire to characterize the sample and identify sedentary behavior and the second obtained nutritional, anthropometric, and body composition data, carrying out biochemical and magnetic resonance imaging tests and investigating physical activity level in this stage. The comparison of the predictive capacity of the VAI with that of other adiposity indicators (body mass index [BMI], waist circumference, waist-height ratio, waist-hip ratio, and neck circumference) for detecting increased VAT and the determination of the optimal cutoff points for the different adiposity indicators were carried out using receiving operating characteristic (ROC) curves. An association was verified between the adiposity indicators and excess visceral fat using Poisson regression analysis with robust variance.

RESULTS

The VAI presented a better predictive capacity for VAT (area under the ROC curve = 0.941), while the BMI did not present diagnostic accuracy (95% CI < 0.5). The strength of the association with high visceral fat was also greater for the VAI than for the other indicators evaluated.

CONCLUSIONS

The VAI was shown to be a better predictor of excess VAT in relation to the other indicators studied. As it is a more easy-access and lower-cost technique than resonance, it enables greater applicability in tracing and monitoring the visceral obesity of a large contingent of military personnel.