Neurodevelopmental Outcome of Extremely Low Birth Weight Infants Fed an Exclusive Human Milk Diet Is Not Affected by Growth Velocity

Abstract

Background: An exclusive human milk (EHM) diet in extremely low birth weight (ELBW) infants (birth weight ≤1,000 g) is linked to an increased likelihood of extrauterine growth restriction (EUGR, weight <10% at discharge). Past studies associated EUGR with worse neurodevelopmental (ND) outcomes; however, its impact when an EHM diet is used is unknown. Objective: Determine whether EUGR adversely affects 2-year ND outcomes of ELBW infants fed an EHM diet. Secondary aims were to compare short-term morbidities and growth through 2 years corrected age (CA). Materials and Methods: Prospective cohort study of ELBW infants fed an EHM diet until 34 weeks corrected gestational age and assessed at 2 years CA. ND outcomes between EUGR and non-EUGR infants were compared using the Bayley Scales of Infant Development 3rd Ed (BSID-III). Results: Eighty-one ELBW infants survived, 44 were seen for follow-up, and 16 (36%) were EUGR. Baseline characteristics and Neonatal Intensive Care Unit (NICU) morbidities were similar. There were no statistically significant differences (median [25-75%]) between EUGR and non-EUGR groups in cognition, (90 [80-99] versus 95 [90-104]), language (84 [68-105] versus 89 [75-100]), or motor composite scores (87 [74-96] versus 91 [88-96]). Weight z-scores during NICU stay dropped in both groups, more pronounced for the EUGR infants. There was no difference in linear or head growth. Conclusion: In our institution, ND outcomes at 2 years CA for ELBW infants fed an EHM diet were similar regardless of EUGR status. This suggests a neuroprotective effect of EHM diet in the ELBW population, despite weight gain velocity during NICU stay.

Keywords: ELBW infant; breastfeeding; human milk diet; neurodevelopment.