Development of a predictive model of body fat mass for newborns and infants

• Published in: Nutrition (Burbank, Los Angeles County, Calif.) Los Angeles County, Calif.), 2023-10, Vol.114, p.112133, Article 112133
• Main Authors: Marano, Daniele, Couto, Elissa de Oliveira, Amaral, Yasmin Notarbartolo di Villarosa do, Junior, Saint Clair Gomes, Ramos, Eloane Gonçalves, Moreira, Maria Elisabeth Lopes
• Format: Article
• Language: English
• Subjects: Age; Anthropometry; Arm circumference; Babies; Births; Body composition; Body fat; Cardiovascular disease; Children & youth; Congenital diseases; densitometry; Gender; Gestational age; Infant; Infants; Methods; Neonates; Newborn; Newborn babies; nutrition; Nutrition monitoring; Plethysmography; Prediction models; Predictive mode; Software; t-test; variance; waist circumference; Weight
• ISSN: 0899-9007; 1873-1244; 1873-1244
• DOI: 10.1016/j.nut.2023.112133

•Weight, sex, and triceps skinfold explained ∼70% of the body fat mass in newborns and and 84% of infants.•The final model for newborns was -0.76638 + 0.2512 * current weight (kg) + 0.06199 * triceps skinfold (mm) + 0.07545 * sex (R² = 70%) and for infants -2.22748 + 0.4928 * current weight (kg) + 0.07375 * triceps skinfold (mm) + 0.246478 * sex (R² = 84%).•Essential tool for assessing the body composition of newborns and infants, which can be applied in health units without access to technologies for measuring body composition. The aim of this study is to develop predictive body fat mass models, one for newborns and one for infants, using air displacement plethysmography as a reference method. The study was carried out with 125 newborns (1–5 d of age) and 71 infants (≥3–6 mo). The stepwise method was used to estimate the final model from the predictors of sex, weight, length, triceps skinfold, waist circumference, mean arm circumference, and gestational age. The quality of the models was evaluated by the determination coefficient, variance inflation factor, and residual analysis. The paired t test and Bland-Altman plot were used to assess the agreement between observed and estimated values. The final model for newborns was - 0.76638 + 0.2512 * weight (kg) + 0.0620 * PCT (mm) + 0.0754 * gender (R² = 70%) and the final model for infants: -2.22748 + 0.4928 * weight (kg) + 0.0737 * TSF (mm) + 0.2647 * gender (R² = 84%). This work determined equations to estimate the BFM of term newborns and infants. The models can be used in clinical practice, especially in health units without access to technologies for measuring body composition, adding important information for nutritional monitoring.