Supplementary Material for: Body Composition of Preterm Infants following Rapid Transition to Enteral Feeding

Objective: This study aimed to evaluate body composition at the time of hospital discharge in very preterm infants following rapid transition to full enteral feeding. Study Design: We conducted a prospective, observational, cross-sectional study and included 105 preterm infants Results: Median and interquartile range (Q1–Q3) of gestational age at birth (GA) was 27.3 (26.1–28.7) weeks and birth weight 845 (687–990) g. Time to reach full enteral feeding was 5 (5–7) days. At 37.6 weeks (36.1–39.0) postmenstrual age (PMA), BF% was 17.0% (14.9–19.8) and FFM 2,161 g (1,966–2,432). BF% was not associated with GA, and not different between small and appropriate for gestational age infants. FFM was significantly lower in infants born small for gestational age. Conclusions: Following rapid transition to full enteral feeding, FFM and BF% at discharge were similar to other preterm populations. BF% and FFM were not associated with GA at birth but with PMA at measurement. FFM was lower and BF% higher compared to term infants at birth, suggesting diminished parenchymal growth in preterm infants. Continued monitoring of body composition, metabolic health, and neurological development is needed to study long-term effects.研究目的：本研究旨在评估极早早产儿快速过渡至全肠内喂养后出院时的身体成分。 研究设计：本研究为前瞻性、观察性横断面研究，共纳入105名早产儿。 研究结果：出生时胎龄（GA，gestational age）的中位数及四分位间距（Q1–Q3）为27.3（26.1–28.7）周，出生体重为845（687–990）g。达到全肠内喂养的时间为5（5–7）天。在校正胎龄（PMA，postmenstrual age）37.6（36.1–39.0）周时，体脂百分比（BF%，body fat percentage）为17.0%（14.9%–19.8%），去脂体重（FFM，fat-free mass）为2161 g（1966–2432 g）。体脂百分比与出生胎龄无相关性，且适于胎龄儿与小于胎龄儿的体脂百分比无显著差异。小于胎龄儿的去脂体重显著更低。 研究结论：在快速过渡至全肠内喂养后，出院时的去脂体重与体脂百分比与其他早产儿队列相似。体脂百分比及去脂体重与出生时胎龄无相关性，但与测量时的校正胎龄相关。与足月出生婴儿相比，早产儿出生时去脂体重更低、体脂百分比更高，提示早产儿实质组织生长受损。未来需持续监测身体成分、代谢健康及神经发育，以探究其长期影响。