Evaluation of ultrasonographic approaches aimed at determining distinct abdominal adipose tissue depots

Objective

To analyze different anatomical sites in the abdominal region, in order to determine the positional parameter that identifies a higher level of visceral adipose tissue (VAT) and confers a greater cardiometabolic risk.

Materials and methods

This is a methodological study in which VAT was evaluated by ultrasonography (USG) in three anatomical sites in the abdomen, while the abdominal circumference (AC) was measured using seven different protocols. Additionally, the glycemic and lipid profile, C-reactive protein, and the presence of systemic arterial hypertension were evaluated.

Results

One hundred and six individuals with an average age of 42 (36.8-46.2) years were included. The evaluation of the calibration of the ultrasound procedure for the analysis of VAT by intra- and inter-evaluators showed high reproducibility. The pattern of abdominal fat distribution differed between sexes, with higher mean VAT in males (p < 0.05) and higher mean SAT (subcutaneous adipose tissue) in females (p < 0.005). In the abdominal scan applied to women, higher levels of VAT and lower levels of SAT were observed in the narrower waist region, between the iliac crest and the last rib (p < 0.001). In males, the profile of adipose disposition along the abdomen was uniform (p > 0.05). Correlations between VAT measured by USG and cardiometabolic parameters were relatively stronger in the upper abdomen (p < 0.05).

Conclusion

Women accumulate more VAT in the narrower waist region, while men accumulate VAT uniformly across the abdomen. There was relative superiority in predicting cardiometabolic risk in the upper abdomen for both sexes.

Ultrasonographic measurement of abdominal and gluteal-femoral fat thickness as a predictor for android/gynoid ratio

OBJECTIVE

To evaluate the use of ultrasonography (US) as an alternative to dual-energy x-ray absorptiometry (DXA) to predict the percentage ratio of android/gynoid (A/G) fat mass.

METHODS

This was a cross-sectional study. Twenty-eight participants included in the study underwent whole-body DXA examinations and the A/G ratio was calculated. Soft-tissue US was performed in several standardised anthropometric areas of the body. Correlation analysis between abdominal and gluteal-femoral fat thickness based on US and A/G ratio was conducted using the Pearson or Spearman test depending on the data normality. Multiple regression analysis using the backward stepwise method was performed to establish an equation for estimating the A/G ratio.

RESULTS

There was a strong and significant correlation between fat thickness in the six anthropometric areas and the A/G ratio in female participants. The analysis revealed three anthropometric areas: upper abdomen (S4), lower abdomen (S5), and mid-xiphoid-umbilical region (S7), that can accurately predict the A/G ratio by 82.3%. (P < 0.05). However, no such correlation was found in male participants.

CONCLUSIONS

US measurement of fat thickness can predict A/G ratio in the female population. However, this method is not recommended for men.

Comparisons of conventional and novel anthropometric obesity indices to predict metabolic syndrome among vegetarians in Malaysia

Our study aimed to compare the ability of anthropometric obesity indices to predict MetS and to determine the sex-specific optimal cut-off values for MetS among Malaysian vegetarians. Body weight, height, waist circumference (WC), blood pressure (BP), fasting venous blood sample were collected from 273 vegetarians in Selangor and Kuala Lumpur, Malaysia. The abilities of body mass index (BMI), body fat percentage (BF%), waist to height ratio (WHtR), lipid accumulation product (LAP), visceral adiposity index (VAI), a body shape index (ABSI), and body roundness index (BRI) to identify MetS were tested using receiver operating characteristic (ROC) curve analyses. MetS was defined according to the Joint Interim Statement 2009. The ROC curve analyses show that BMI, BF%, WHtR, LAP and VAI were able to discriminate MetS in both sexes. LAP was a better predictor to predict MetS, followed by WHtR for male and female vegetarians. The suggested WHtR’s optimal cut-offs and LAP’s optimal cut-offs for MetS for male and female vegetarians were 0.541, 0.532, 41.435 and 21.743, respectively. In conclusion, LAP was a better predictor to predict MetS than other anthropometric obesity indices. However, WHtR could be an alternative obesity index in large epidemiology survey due to its convenient and cost-effective characteristics.

The Potential for Using Sonography to Measure Abdominal Adiposity in Children

The accumulation of abdominal adiposity has been associated with many risk factors in adults and children. Currently, body mass index (BMI) percentiles, computed tomography (CT), and dual X-ray absorptiometry (DXA) are widely used to evaluate body fat but are not widely acceptable for measuring visceral and subcutaneous adiposity. The aim of this study was to evaluate abdominal adiposity in children by the use of diagnostic medical sonography (DMS). Fifty-eight third graders were recruited for a 10-week interventional study. This cohort received baseline body composition and anthropometric measures, including height, weight, calculated BMI percentiles, blood pressure, bioelectric impedance, and DMS. The resulting data analysis provided a set of descriptive statistics. DMS may be a reliable, practical, and cost-effective method for measuring visceral and subcutaneous adiposity across varied body compositions of children.