[Abdominal fat assessment by magnetic resonance: comparison with biometric profiles and cardiovascular risk markers]

Independent and combined associations of solid-fuel use and smoking with obesity among rural Chinese adults

Although solid-fuel use or smoking is associated with obesity measured by body mass index (BMI), research on their interactive effects on general and central obesity is limited. Data of 20,140 individuals in the Henan Rural Cohort Study was examined the independent and combined associations of solid-fuel use and smoking with prevalent obesity, which was measured by BMI, waist circumference (WC), waist-to-hip ratio (WHR), waist-to-height ratio (WHtR), body fat percentage (BFP), and visceral fat index (VFI). Multiple adjusted logistic regression models showed that the OR (95% CI) of prevalent obesity measured by BMI associated with exposure to solid fuels alone or with smoking was 0.78 (0.70, 0.86) or 0.46 (0.32, 0.66), compared with neither smoking nor solid-fuel exposure. Similar results had been found in other obese anthropometric indices and in the results of linear regression analysis. The results indicated that solid-fuel use and smoking have a synergistic effect on reduction in obesity indices. The effects of household air pollution from solid-fuel use and smoking on obesity should be considered when exploring the influencing factors of obesity.

[Sensitivity and specificity of abdominal adiposity with metabolic syndrome in the elderly]

OBJECTIVES

It is recognised that abdominal adiposity is associated with cardiovascular risk factors, such as intolerance to glucose, hypertension and dyslipidaemia. The objective of the present study was to assess the relationship of trunk fat and visceral fat index, obtained by anthropometric and bioelectrical impedance, with metabolic syndrome (SM) in an elderly population.

METHODS

The study included 208 subjects (78 men and 130 women) with a mean age of 82.5 years. Abdominal obesity was assessed by anthropometry and bioelectrical impedance. ROC curves were calculated in order to assess the ability of these variables to diagnose metabolic syndrome.

RESULTS

There are differences between men and women in body mass index, waist to height ratio, waist circumference, and bioelectrical impedance measurements as trunk fat and visceral fat (p<.05). Also, found differences in anthropometric indices and variables and abdominal bioelectrical impedance between subjects with and without SM (p<.05) and only exist differences in blood glucose, triglycerides and HDL cholesterol (p<.05). There are significant correlations between anthropometric variables and abdominal bioelectrical impedance (p<.05). Areas under the curve (AUC) of waist to height index, waist circumference, sagittal abdominal diameter, and trunk fat were greater than 0.8 (all p<.01), and in women did not exceed values of 0.65. The cut-off points obtained for BMI were 26.81 and 23.53kg/m², 102 and 91cm for waist circumference, 22.1 and 20.7cm for sagittal abdominal diameter, 34% and 43.7% for trunk fat, and 17 and 11.5 for visceral fat ratio in men and women, respectively.

CONCLUSIONS

There are different levels of predictive ability for metabolic syndrome according to gender. Trunk fat and visceral fat index and anthropometric measures have higher predictive ability for metabolic syndrome in men than in women.

Simple anthropometric measures correlate with metabolic risk indicators as strongly as magnetic resonance imaging-measured adipose tissue depots in both HIV-infected and control subjects

BACKGROUND

Studies in persons without HIV infection have compared percentage body fat (%BF) and waist circumference as markers of risk for the complications of excess adiposity, but only limited study has been conducted in HIV-infected subjects.

OBJECTIVE

We compared anthropometric and magnetic resonance imaging (MRI)-based adiposity measures as correlates of metabolic complications of adiposity in HIV-infected and control subjects.

DESIGN

The study was a cross-sectional analysis of 666 HIV-positive and 242 control subjects in the Fat Redistribution and Metabolic Change in HIV Infection (FRAM) study assessing body mass index (BMI), waist (WC) and hip (HC) circumferences, waist-to-hip ratio (WHR), %BF, and MRI-measured regional adipose tissue. Study outcomes were 3 metabolic risk variables [homeostatic model assessment (HOMA), triglycerides, and HDL cholesterol]. Analyses were stratified by sex and HIV status and adjusted for demographic, lifestyle, and HIV-related factors.

RESULTS

In HIV-infected and control subjects, univariate associations with HOMA, triglycerides, and HDL were strongest for WC, MRI-measured visceral adipose tissue, and WHR; in all cases, differences in correlation between the strongest measures for each outcome were small (r

CONCLUSION

Relations of simple anthropometric measures with HOMA, triglycerides, and HDL cholesterol are approximately as strong as MRI-measured whole-body adipose tissue depots in both HIV-infected and control subjects.

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MESH Headings

• Adipose Tissue/anatomy & histology
• Adult
• Anthropometry/methods
• Body Mass Index
• Body Size
• Cross-Sectional Studies
• Female
• HIV Infections/complications
• HIV Infections/epidemiology
• Humans
• Magnetic Resonance Imaging/methods
• Male
• Middle Aged
• Patient Selection
• Predictive Value of Tests
• Reference Values
• Risk Assessment
• Waist-Hip Ratio

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Grants

• HL74814 NHLBI NIH HHS
• R01 HL074814-06 NHLBI NIH HHS
• R01 DK057508-03S1 NIDDK NIH HHS
• M01 RR000054 NCRR NIH HHS
• RR00052 NCRR NIH HHS
• RR0636 NCRR NIH HHS
• M01 RR000083 NCRR NIH HHS
• RR00054 NCRR NIH HHS
• R01 DK057508-03 NIDDK NIH HHS
• R01 DK057508-01S1 NIDDK NIH HHS
• RR00865 NCRR NIH HHS
• R01-DK57508 NIDDK NIH HHS
• R01 DK057508 NIDDK NIH HHS
• R01 HL074814-07 NHLBI NIH HHS
• R01 DK057508-01 NIDDK NIH HHS
• RR00083 NCRR NIH HHS
• M01 RR000865 NCRR NIH HHS
• M01 RR000036 NCRR NIH HHS
• HL 53359 NHLBI NIH HHS
• R01 HL074814-04 NHLBI NIH HHS
• RR00051 NCRR NIH HHS
• R01 DK057508-03S2 NIDDK NIH HHS
• M01 RR000052 NCRR NIH HHS
• R01 HL074814-05 NHLBI NIH HHS
• M01 RR000051 NCRR NIH HHS
• M01-RR00036 NCRR NIH HHS
• R01 HL074814 NHLBI NIH HHS
• R01 DK057508-02 NIDDK NIH HHS

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Affiliation(s)

Rebecca Scherzer Northern California Institute for Research and Education, San Francisco, CA, USA
Wei Shen
Peter Bacchetti
Donald Kotler
Cora E Lewis
Michael G Shlipak
Steven B Heymsfield
Carl Grunfeld

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Quantitative comparison and evaluation of software packages for assessment of abdominal adipose tissue distribution by magnetic resonance imaging

OBJECTIVE

To examine five available software packages for the assessment of abdominal adipose tissue with magnetic resonance imaging, compare their features and assess the reliability of measurement results.

DESIGN

Feature evaluation and test-retest reliability of softwares (NIHImage, SliceOmatic, Analyze, HippoFat and EasyVision) used in manual, semi-automated or automated segmentation of abdominal adipose tissue.

SUBJECTS

A random sample of 15 obese adults with type 2 diabetes.

MEASUREMENTS

Axial T1-weighted spin echo images centered at vertebral bodies of L2-L3 were acquired at 1.5 T. Five software packages were evaluated (NIHImage, SliceOmatic, Analyze, HippoFat and EasyVision), comparing manual, semi-automated and automated segmentation approaches. Images were segmented into cross-sectional area (CSA), and the areas of visceral (VAT) and subcutaneous adipose tissue (SAT). Ease of learning and use and the design of the graphical user interface (GUI) were rated. Intra-observer accuracy and agreement between the software packages were calculated using intra-class correlation. Intra-class correlation coefficient was used to obtain test-retest reliability.

RESULTS

Three of the five evaluated programs offered a semi-automated technique to segment the images based on histogram values or a user-defined threshold. One software package allowed manual delineation only. One fully automated program demonstrated the drawbacks of uncritical automated processing. The semi-automated approaches reduced variability and measurement error, and improved reproducibility. There was no significant difference in the intra-observer agreement in SAT and CSA. The VAT measurements showed significantly lower test-retest reliability. There were some differences between the software packages in qualitative aspects, such as user friendliness.

CONCLUSION

Four out of five packages provided essentially the same results with respect to the inter- and intra-rater reproducibility. Our results using SliceOmatic, Analyze or NIHImage were comparable and could be used interchangeably. Newly developed fully automated approaches should be compared to one of the examined software packages.

[Cardiovascular risk factors in patients with morbid obesity: weight loss influence]

BACKGROUND

We studied the presence of cardiovascular risk factors in patients with morbid obesity and analyzed the influence of weight loss achieved through diet on these factors. We also evaluated the influence of gender on the presence of cardiovascular risk factors and on its response to diet.

PATIENTS AND METHODS

An anthropometric evaluation was performed in patients with morbid obesity (23 men and 36 women). The presence of cardiovascular risk factors was evaluated (fibrinogen, blood pressure, glucose metabolism determination by means of oral glucose tolerance test, complete lipid profile, sleep apnea syndrome), before and after following, on an alternative fashion, very-low calorie and low-calorie diets. The comparison was made with the t-test for paired samples.

RESULTS

A very significant weight loss was achieved in our patients, particularly in men (decrease of 33.4 kg, 95% CI: 26.9 to 39.8). This was accompanied by a reduction in the presence of cardiovascular risk factors, particularly in men, in whom the body fat distribution improved significantly (decrease in waist: 24.8 cm, 95% CI 18.4 to 36.5), as well as the lipid profile including triglycerides, VLDLc, HDLc and B100 apoprotein.

CONCLUSIONS

Patients with morbid obesity have a high prevalence of cardiovascular risk factors. A significant reduction of this prevalence can be achieved with diet during one year. This improvement is particularly significant in men.