Prediction of basal metabolic rate in obese children and adolescents considering pubertal stages and anthropometric characteristics or body composition

BACKGROUND/OBJECTIVES: To develop and crossvalidate new equations for predicting basal metabolic rate (BMR) in obese children and adolescents in relation to pubertal stages, anthropometric characteristics or body composition. SUBJECTS/METHODS: A total of 1696 obese Caucasian children and adolescents (mean body mass index z-score: 3.5 ± 0.8) participated in this study. BMR was determined by indirect calorimetry and fat-free mass (FFM) and fat mass (FM) by bioelectrical impedance analysis. Equations were derived by stepwise multiple regression analysis using a calibration cohort of 848 subjects, and the equations were crossvalidated with a Bland and Altman method in the remaining 848 subjects. RESULTS: Two new specific equations based on gender (1: males; 0: females), pubertal stages (from 1 to 5, assessed according Marshall & Tanner methods) and body weight (BW, kg), stature (m) or body composition (kg) were generated as follows: (1) BMR = (BW x 0.044) + (stature x 2.836) - (pubertal stage x 0.148) + (gender x 0.781) - 0.551 (adjusted coefficient of determination ([R.sup.2.sub.adj]) = 0.69 and root mean squared error (RMSE) = 0.954 MJ);(2) BMR = (FFM x 0.082) + (FM x 0.037) - (pubertal stage x 0.125) + (gender x 0.706) + 2.528 ([R.sup.2.sub.adj] = 0.70 and RMSE = 0.943 MJ). In the crossvalidation group, mean-predicted BMR was not significantly different from the mean-measured BMR (MBMR) for all children and adolescents, as well as for boys and girls (difference < 2 %), and the limits of agreement ([+ or -] 2 s.d.) were +1.95 and -1.98 MJ/d, (P = NS). BMR was predicted accurately (90-110% of MBMR) in 67% of subjects. CONCLUSION: The new prediction equations considering the pubertal stages allow an accurate and more appropriate (vs equations using chronological age) estimation of BMR in obese children and adolescents. European Journal of Clinical Nutrition (2014) 68, 695-699; doi:10.1038/ejcn.2014.26; published online 5 March 2014
INTRODUCTION Obesity is an increasing health problem in children and adolescents in all countries of the industrialized world. (1,2) The progressive increase in adiposity is the result of a prolonged [...]