Growth and Body Composition after Term in Two Subgroups of VLBW Infants: Preliminary Data of a Randomized Controlled Trial

BACKGROUND: Growth benefits have been reported in infants with birth weight less than 1250 g and in boys when nutrient-enriched formula (PDF) are fed after discharge. OBJECTIVE: To evaluate whether the use of a PDF may determine a growth benefit in two sub-groups of infants. DESIGN/METHODS: 118 preterm infants, born AGA (BW=1178.7± 226 g; GA=29±1.9 wks) and 61 preterm infants, born SGA (BW=1105± 253g; GA=31.5±1.8 wks) were randomized in G1a [AGA fed PDF (2.9 g/100 kcal)], G1b [AGA fed term formula (TF) (2.1 g/100 kcal)], G2a: SGA fed PDF, G2b: SGA fed TF. Measures: growth and body composition, by an air displacement plethysmography system, at term, 1, 3, 5, 6 months of corrected age. Statistical analysis: ANOVA, regression analysis. RESULTS: Protein intakes were higher in G1a than G1b (p<0.005) and in G2a than G2b(p<0.05) at each study point. Weight, length and fat mass were similar in AGA and SGA infants either fed PDF or TF at each study point. Mean head circumference values (cm) were higher in G1a than G1b at six months (43.4± 2 vs 42.3±1.5, p=0.03). In AGA infants, at linear regression analysis (p<0.001), being fed a PDF formula, being male, being born AGA without postnatal growth retardation at term were correlated with higher head circumference values at six months [unstandardized B coefficient (SE) 1.4 (0.47); 1 (0.44); 1 (0.44), respectively). CONCLUSIONS: Our data suggest a growth benefit in AGA preterm infants fed PDF.