Body composition estimation using skinfolds in children with and without health conditions affecting growth and body composition

Abstract

Background Body composition prediction equations using skinfolds are useful alternatives to advanced techniques, but their utility across diverse pediatric populations is unknown. Aim To evaluate published and new prediction equations across diverse samples of children with health conditions affecting growth and body composition. Subjects and Methods Anthropometric and dual-energy x-ray absorptiometry (DXA) body composition measures were obtained in children with Down syndrome (n=59), Crohn disease (n=128), steroid-sensitive nephrotic syndrome (n=67), and a healthy reference group (n=835). Published body composition equations were evaluated. New equations were developed for ages 3 to 21y using the healthy reference sample and validated in other groups and national survey data. Results Fat mass [FM], fat-free mass [FFM] and percent body fat [%BF]) from published equations were highly correlated with DXA-derived measures (r=0.71 to 0.98), but with poor agreement (mean difference: 2.4kg, −1.9kg, and 6.3% for FM, FFM and %BF). New equations produced similar correlations (r=0.85 to 1.0) with improved agreement for the reference group (0.2kg, 0.4kg, and 0.0% for FM, FFM and %BF, respectively), and in sub-groups. Conclusions New body composition prediction equations show excellent agreement with DXA, and improve body composition estimation in healthy children and those with selected conditions affecting growth.

Body Composition in Children with Chronic Illness: Accuracy of Bedside Assessment Techniques

“…The Wendel 2SF and 4SF equations for males and females had a correlation coefficient between 0.85 to 0.92. 12 In our study all SF-based estimating equations had strong correlation coefficients but wide limits of agreement, reducing their clinical applicability. The inaccuracy of SF-based FM estimating equations may be due to inaccurate measurement of SF or invalid equations that were derived from healthy pediatric populations.…”

“…In relation to reference methods such as DXA and deuterium isotope dilution method, these equations have correlation coefficients greater than 0.9. 12–20 These equations were derived using body composition data from mostly healthy children from diverse ethnic backgrounds and a wide age range. In our current study, BIA based FFM estimating equations had strong linear correlation with reference methods, but limits of agreement were wider than +/− 20%.…”

“…9–11 These techniques use equations to estimate FM from skinfold measurements; or estimate FM and FFM using equations applied to impedance and resistance values obtained by BIA. 12–20 These equations have been developed in heterogeneous cohorts of children, a majority of whom have no comorbidities.…”

Deficits in Muscle Strength and Physical Performance Influence Physical Activity in Sarcopenic Children After Liver Transplantation

“…The intrasubject coefficient of variation for all of the individual skinfolds measured for the LT and HC groups ranged between 1% and 3% ( P = 0.78). FFM from 4 skinfolds (at the biceps, triceps, subscapular, and suprailiac) were calculated according to a predictive equation . A Bland‐Altman plot was used to assess agreement in FFM determinations between DXA and multiple skinfold measures .…”

“…FFM from 4 skinfolds (at the biceps, triceps, subscapular, and suprailiac) were calculated according to a predictive equation. (20) A Bland-Altman plot was used to assess agreement in FFM determinations between DXA and multiple skinfold measures. (21) FFMI (FFMI = FFM/height 2 [absolute/z score]) was determined according to normative data.…”