Associations of Measured Protein and Energy Intakes with Growth and Adiposity in Human Milk-Fed Preterm Infants at Term Postmenstrual Age: A Cohort Study

Abstract

Objective To determine the associations of measured protein, energy, and protein-to-energy (PER) intakes with body composition in human milk (HM)-fed preterm infants. Study Design Neonates born at < 33 gestational weeks were eligible. Standard fortification method with modular supplements was used and the HM composition was measured. The weight gain velocity was calculated, and body composition was assessed by air displacement plethysmography at 40 weeks' postmenstrual age (PMA). The fat mass percentage and fat mass index were used as indicators of adiposity, with convenience cut-offs ≤ –1 and ≥ + 1 z-scores for low and high adiposity, respectively. Results Thirty-three infants were included (median [interquartile range] gestational age: 30 [28–31] weeks; birth weight: 1.175 [1.010–1.408] g); 36.4 and 84.8% did not receive the minimum recommended protein and energy intakes, respectively. Weight gain velocity showed positive weak-to-moderate correlations with nutrient intakes. Overall, no correlations between nutrient intakes and body composition were found. Infants with lower adiposity received lower energy, protein, and PER intakes, while those with higher adiposity received lower energy intake but higher PER intake. Conclusion Overall, no correlations of nutrient intakes with body composition were found; however, differences in nutrient intakes were found between infants with lower and higher adiposity at term PMA.