Category: Morphometric Measurements: (Body Composition, Vertebral Fracture Recognition, Hip Geometry)

26 - Relationship between DXA-based visceral fat and other total body and regional fat assessments.

Background: Studies have suggested that assessing how fat is distributed--especially fat distribution within the abdomen-- in the body may aid is assessing individual risk to subjects. The current study evaluates the utility of applying the DXA study to this purpose by examining the relationship between regional and total DXA-based fat content and anthropometrically or MRI assessed total body or abdominal fat content.

A cohort of 86 adult male subjects between 24 and 88 years of age underwent a total body and abdominal (visceral)composition study using the Norland XR-800. These subjects also underwent assessment of weight, height and waist and hip circumference to calculate a composition estimate. These measurements enabled analysis of the relationships between the DXA based abdominal assessment and the Siri Classification Grade for total body fat, Body Mass Index, Waist Circumference and Waist-Hip Ratio. Additionally, 18 other subjects between 12 and 17 years of age underwent evaluation by DXA and MRI to evaluate the relationship between DXA-based abdominal and MRI-based visceral fat assessments. Relationships between various assessments were analyzed by regression analysis and an ANOVA independent group evaluation by the Tukey-Kramer Method.

Regression analysis has documented that DXA based abdominal fat is strongly related to total body fat (y = 0.1144x -430.43; r = 0.9318) and MRI-based visceral fat (y = 0.1299x - 106.73; r = 0.8776). Significant positive regressions were also documented between the DXA based abdominal fat and Body Mass Index (y = 70.03x - 2368.8; r = 0.7388), waist circumference (y = 62.046x - 3560.5; r = 0.6853) and the Waist-Hip Ratio (y = 6821.2x - 4176.5; r = 0.5360). Evaluating the significant difference by Siri Classification Grade showed significant difference between all four groups in DXA based abdominal fat and waist circumference with patchy differences found when Body Mass Index and Waist-Hip Ratio were evaluated.

The study demonstrates that the Norland abdominal fat assessment reflects visceral fat and obesity related fat mass over a wide range of samples and suggests that this evaluation can be applied when investigating potential risk associated with abdominal fat content.

Chad A Dudzek

Software Engineer
Norland at Swissray
Fort Atkinson, Wisconsin

Tom V. Sanchez

Chief Science Officer
Norland at Swissray
Socorro, New Mexico

Yun Sun

Assistant Professor
Hospital of Tsinghua University
Beijing, Beijing, China (People's Republic)

Jingmei Wang

Director of Densitometry Research
Norland at Swissray
Beijing, Beijing, China (People's Republic)