Suresh Anand Sadananthan1, Navin Michael1, Mya Thway Tint2, Kuan Jin Lee3, Jay Jay Thaung Zaw2, Khin Thu Zar Hlaing2, Pang Wei Wei2, Lynette Pei-Chi Shek4, Yap Kok Peng Fabian5,6, Peter D. Gluckman1,7, Keith M. Godfrey8, Yap Seng Chong1,2, Melvin Khee-Shing Leow9,10, Yung Seng Lee1,4, Christiani Jeyakumar Henry9, Marielle Valerie Fortier11, and S. Sendhil Velan1,3
1Singapore Institute for Clinical Sciences, A*STAR, Singapore, 2Department of Obstetrics & Gynaecology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, 3Singapore BioImaging Consortium, A*STAR, Singapore, 4Department of Paediatrics, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, 5Department of Paediatric Endocrinology, KK Women’s and Children’s Hospital, Singapore, 6Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore, 7Liggins Institute, University of Auckland, Auckland, New Zealand, 8MRC Lifecourse Epidemiology Unit & NIHR Southampton Biomedical Research Centre, University of Southampton & University Hospital Southampton NHS Foundation Trust, Southampton, United Kingdom, 9Clinical Nutrition Research Centre, Singapore Institute for Clinical Sciences, A*STAR, Singapore, 10Department of Endocrinology, Tan Tock Seng Hospital, Singapore, 11Department of Diagnostic and Interventional Imaging, KK Women’s and Children’s Hospital, Singapore
Synopsis
Longitudinal
assessment of abdominal fat compartments in children can help delineate some of
the early risk factors that can predispose an individual to high abdominal
adiposity and insulin resistance. While accurate determination of abdominal fat
can be achieved using CT or MRI, it is often not performed in large cohort
studies involving young children due to radiation exposure, high costs or poor
compliance with scan procedures. The goal of this work is to develop and
validate predictive equations for abdominal fat compartments from
anthropometric values with MRI-based abdominal fat volumes as reference in
multi-ethnic cohort of 4.5 year-old Asian children.Introduction
Longitudinal
assessment of abdominal fat compartments in children may help delineate some of
the early risk factors that can predispose an individual to high abdominal
adiposity and insulin resistance. While accurate determination of abdominal fat
can be achieved using computed tomography (CT) or magnetic resonance imaging
(MRI), it is often not performed in large cohort studies involving young
children due to radiation exposure, high costs or poor compliance with scan
procedures. The goal of this work is to develop and validate predictive equations
for abdominal fat compartments (subcutaneous (SAT) and internal (IAT) adipose
tissue) from anthropometric values with MRI-based abdominal fat volumes as
reference in multi-ethnic cohort of 4.5 year-old Asian children.
Methods
Our data for the study included observations from 54 children (31 Chinese, 14
Malays and 9 Indians) aged 4.5 years from the Growing Up in Singapore Towards healthy
Outcomes (GUSTO) study [1]. Anthropometric measures including height, weight,
abdominal and upper mid-arm circumference and skinfold thickness (subscapular,
triceps, biceps and suprailiac) were measured. Axial abdominal images with 5
mm slice thickness and in-plane resolution of 0.94 × 0.94 mm were acquired
using water suppressed HASTE sequence (TR=1000 ms, TE=95 ms) on the 3T MR
scanner (Siemens Skyra). The SAT and IAT volumes between the diaphragm
and S1 sacral level were segmented with an automated algorithm [2] and edited
manually for correction of any mis-segmented regions. The total sample (n=54) was randomly
divided into training (n=30) and testing (n=24) groups. Statistical analyses
were performed using SPSS 23.0 software. Linear predictive models were created
for the SAT and IAT depots with anthropometric measures, ethnicity, weight, height
and gender as potential predictors. Forward stepwise selection was performed
using the Akaike information criterion (AIC) to select/remove predictors from
the model in an automated fashion. The predictive equation derived from the
training set was validated against the MRI-based fat volumes of the test set.
Results
The optimal
predictive equations yielded by the linear modeling for SAT and IAT are shown
in Table 1. Within the training dataset (Fig. 1 & 2), the equations had a strong
predictive power for SAT (R
2 = 0.97) and a moderate predictive power
for IAT (R
2 = 0.73). When the equations were cross-validated on the
test dataset (Fig. 3 & 4), the R
2 for prediction of SAT was 0.88, while R
2 for IAT was 0.32. Body
weight was the strongest predictor of IAT.
Conclusion
We have
developed equations to predict abdominal fat depot volumes using anthropometric
measures in 4.5 year-old Asian children. We found that SAT can be predicted
with high accuracy from anthropometric measures while equation for IAT had poor
predictive power. These equations will benefit large cohort studies in Asian
preschoolers for the interpretation of anthropometric data with regard to abdominal
fat partitioning.
Acknowledgements
This
research is supported by the Singapore National Research Foundation under its
Translational and Clinical Research (TCR) Flagship Programme and administered
by the Singapore Ministry of Health’s National Medical Research Council (NMRC),
Singapore- NMRC/TCR/004-NUS/2008; NMRC/TCR/012-NUHS/2014. Additional funding is
provided by the Singapore Institute for Clinical Sciences, Agency for Science
Technology and Research (A*STAR), Singapore.References
[1] Shu-E et al., Cohort Profile: Growing Up in Singapore
Towards healthy Outcomes (GUSTO) birth cohort study. International Journal of Epidemiology
2014, 43(5):1401-1409.
[2] Suresh Anand Sadananthan et al., Automated
Segmentation of Visceral and Subcutaneous (Deep and Superficial) Adipose Tissues
in Normal and Overweight Men. Journal of Magnetic Resonance in Imaging 2015,
41(4):924-934.