Contemporary Definitions of Infant Growth Failure and Neurodevelopmental and Behavioral Outcomes in Extremely Premature Infants at Two Years of Age

INTRODUCTION: The association of 2-year neurodevelopmental and behavioral outcomes with in-hospital or post-discharge growth failure (GF) using contemporary definitions for preterm infants is unknown. METHODS: In a secondary analysis of a preterm cohort, changes in anthropometric z-scores were examined between birth and hospital discharge, and from discharge to 2 years. The 2-year evaluation included Bayley Scales of Infant Development (BSID-III) and Child Behavior Checklist (CBCL). RESULTS: Among 629 infants, accelerated linear growth from birth to discharge was associated with higher BSID-III cognitive scores (+ 3.2 points [IQR 0.02, 6.4]) while in-hospital GF was not associated with any outcomes. Infants with weight GF after discharge had lower BSID-III motor scores (−3.1 points [−5.9, −0.2]). Infants with accelerated weight growth after discharge had increased odds of behavioral problems on the CBCL (aOR 1.9 [1.03, 3.5]). DISCUSSION: In-hospital and post-hospitalization growth metrics are modestly associated with neurodevelopmental outcomes with length gains apparently most beneficial.