Infant nutrition (donor human milk vs. maternal milk) and long-term neurodevelopmental and growth outcomes in very low birth weight infants

Background: Human milk, the ultimate source of nutrition for premature infants, enhances host defense mechanism, gastrointestinal maturation, lowers infection rate, improves neurodevelopmental outcomes, and reduces long-term cardiovascular and metabolic disease. Recently, there has been an increase in donor breast milk (DBM) use for premature infants; however, data are limited on the long-term effects of DBM on the infant's growth and neurodevelopmental outcomes.

Objective: To determine if there is an association between type of infant nutrition (maternal breast milk (MBM) or DBM) and neurodevelopmental and growth outcomes in very low birth weight (VLBW) infants.

Design/methods: Retrospective cohort study of VLBW (<1500 g) infants admitted to the Baylor Scott & White Memorial Hospital Neonatal Intensive Care Unit from January 2014 to December 2016. Infants with major congenital anomalies, born at an outside hospital, who were nil per os (NPO) for >15 days, or who died before NICU discharge were excluded. Infants were stratified into two groups (MBM or DBM) based on predominant nutrition (>50%) received in the first month of life. Primary outcomes of neurodevelopmental delay(s) between 2 and 4 years of age identified via ICD 9/10 codes. Growth data (weight, length, and head circumference) were obtained from well-check visits at 12-, 18-, 24-, 36-, and 48-months. Severity of illness was determined using the Clinical Risk Index in Babies-II (CRIB-II) score. Generalized linear models were used to assess the relationship between nutrition and neurodevelopmental delay and trends in growth over time.

Results: Two hundred and nine infants were included: 146 MBM; 63 DBM. Median gestational age was 28 weeks (range, 23-35) and median birthweight was 1050 g (range, 410-1470). There were no significant differences in birthweight, gestational age, CRIB-II score, or length of stay between the groups. Infants fed DBM had a significantly larger weight z-score (p=.005), length z-score (p=.01), and head circumference z-score (p=.04), on average from birth to 48 months compared to MBM infants, while controlling for NICU length of stay and number of follow-up months; however, this only equated to DBM infants being 0.5 in taller and 0.9 lbs heavier at 48 months. There were no statistically significant differences among type of infant nutrition and long-term neurodevelopmental outcomes, while controlling for CRIB-II score.

Conclusions: Infants fed DBM have a slightly greater propensity for growth over time compared to infants fed MBM. Longer follow-up is needed to further determine the effect, infant nutrition has on neurodevelopmental outcomes.