the relationship between early weight z-score changes and nutritional differences in very low birth weight infants during hospital stay

Background: advances in neonatal care have resulted in improved survival for very low birth weight infants (vlbwis). however, the main factors that lead to early weight z-score [standard deviation score (sds)] changes during hospital stay in vlbwis still need to be studied more. objectives: in this study we aimed to investigate the differences in specific factors that relate to vlbwis’ early weight z-score changes as the scientific basis for clinical practice of vlbwis during the entire hospital stay. methods: we retrospectively reviewed baseline characteristics, nutrition management, clinical outcomes, and complications between non-catch-down (ncd) (weight sds< -0.67) and catch-down (cd) groups (weight sds < -0.67) in vlbwis during hospital stay. results: a total of 227 infants (ncd group = 117, cd group = 110) met the inclusion criteria. no significant differences were found in baseline characteristics between the two groups. the ncd group received higher parenteral lipids (g/kg/d) from day 5 to day 7 and higher enteral feeding volume (ml/kg/d) from day 5 to week 5. the ncd group had higher protein:energy ratios at day 2 to day 4 and day 7 and higher total energy (kcal/kg/d) during the first six weeks. the ncd group had lower incidence of bronchopulmonary dysplasia (bpd) and parenteral nutrition-associated cholestasis (pnac). conclusions: this study showed that adequate parenteral lipid and energy at the first week of life and earlier enhanced enteral feeding volume might significantly improve the vlbwis’ weight z-scores during hospital stay. the vlbwis with catch-down growth might be more prone to developing bpd and pnac.