Body mass index growth trajectories and body composition influencing factors: An ambidirectional preschooler cohort.

ABSTRACT

OBJECTIVES: The purpose of the present study was to explore the latent growth trajectory of body mass index (BMI) from birth to 24 months and comprehensively analyze body composition development influencing factor in preschool children. METHODS: This ambidirectional cohort study was conducted in Tianjin, China, from 2017 to 2020, and children's regular medical check-up data from birth to 24 months were retrospectively collected. The growth models were used to fit BMI z-score trajectories for children aged 0-24 months. Crossover analysis and interaction model were used to explore the interaction of influencing factors. RESULTS: We analyzed the growth trajectories of 3217 children, of these, 1493 children with complete follow-up data were included in the influencing factors analysis. Trajectories and parental prepregnancy BMI (ppBMI) were independent factors influencing children's body composition. When paternal ppBMI ≥24 kg/m2, regardless of maternal ppBMI, the risk of overweight and obesity in senior-class children was increased. The high trajectories played a partial mediating role in the association between paternal ppBMI and body composition in preschool children. CONCLUSIONS: BMI growth in children aged 0-24 months can be divided into three latent trajectories low, middle, and high. These trajectories and parental ppBMI were independent and interactive factors influencing children's body composition. The high trajectories played a partial mediating role in the association between paternal ppBMI and body composition in preschool children. It is necessary to pay attention to the BMI growth level of children aged 0-24 months, which plays an important role in the development of body fat in the future.