[pronut-hiv] Breast Milk Feeding Improves Outcomes in Extremely Low Birth Weight Children

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July 20, 2006 * Breast milk feeding of extremely low birth weight (ELBW) children in the neonatal intensive care unit (NICU) improves outcomes, including reducing the need for special education, according to the results of a prospective study reported in the July issue of Pediatrics.

"Beneficial effects of breast milk on cognitive skills and behavior ratings have been demonstrated previously in term and very low birth weight infants," write Betty R. Vohr, MD, from Brown Medical School in Providence, RI, and colleagues from the National Institute of Child Health and Human Development (NICHD) Neonatal Research Network. "Extremely low birth weight infants are known to be at increased risk for developmental and behavior morbidities. The benefits of breast milk that is ingested in the NICU by ELBW infants on development and behavior have not been evaluated previously."

The objective of this study was to determine the relationship of breast milk ingestion with developmental and behavior test scores and rehospitalization after discharge from the NICU, using a cohort of ELBW infants who were born after the publication of the 1997 American Academy of Pediatrics statement recommending that ELBW infants receive breast milk.

At 15 sites participating in the NICHD Neonatal Research Network Glutamine Trial, the investigators prospectively collected data from 1035 ELBW infants between October 14, 1999, and June 25, 2001. Outcome measures included enteral and parenteral nutrition, follow-up assessments at 18 months' corrected age, total volume of breast milk feeds (mL/kg/day) during hospitalization, neonatal characteristics and morbidities, interim history, and neurodevelopmental and growth outcomes at 18- to 22-months' corrected age.

Of the 1035 ELBW infants, 775 (74.9%) were in the breast milk and 260 (25.1%) were in the no breast milk group. Both groups were similar in every neonatal characteristic and morbidity, including number of days of hospitalization. For the breast milk infants, mean age of first day of breast milk was 9.3 ± 9 days. Compared with the no breast milk group, infants in the breast milk group began to ingest non-breast-milk formula later (22.8 vs 7.3 days). The breast milk and no breast milk groups had similar age at achieving full enteral feeds (29.0 ± 18 vs 27.4 ± 15), as well as similar energy intakes during hospitalization (107.5 vs 105.9 kg/day).

After adjustment for maternal age, maternal education, marital status, race/ethnicity, and other standard covariates, children in the breast milk group were more likely to have a Bayley Mental Development Index of 85 or higher, higher mean Bayley Psychomotor Development Index, and higher Bayley Behavior Rating Scale percentile scores for orientation/engagement, motor regulation, and total score. However, rates of moderate to severe cerebral palsy or blindness or hearing impairment were similar in both groups, as were mean weight (10.4 vs 10.4 kg), length (80.5 vs 80.5 cm), and head circumference (46.8 vs 46.6 cm) at 18 months.

Adjusted multivariate analyses confirmed a significant independent association of breast milk on all 4 primary outcomes: the mean Bayley Mental Development Index, Psychomotor Development Index, Behavior Rating Scale, and incidence of rehospitalization. For every 10-mL/kg/day increase in breast milk ingestion, the Mental Development Index increased by 0.53 points, the Psychomotor Development Index increased by 0.63 points, the Behavior Rating Scale percentile score increased by 0.82 points, and the probability of rehospitalization decreased by 6%. The impact of breast milk ingestion during the hospitalization for infants in the highest quintile (110 mL/kg/day) on the Bayley Mental Development Index would be 10 x 0.53 or 5.3 points.

"An increase of 5 points potentially would optimize outcomes and decrease costs by decreasing the number of very low birth weight children who require special education services," the authors write. "The societal implications of a 5-point potential difference (one third of an SD) in IQ are substantial. The potential long-term benefit of receiving breast milk in the NICU for extremely low birth weight infants may be to optimize cognitive potential and reduce the need for early intervention and special education services."

Study limitations include lack of data on use of breast milk after discharge and on the home environment.

"The provision of breast milk to ELBW infants during the neonatal period is an easy-to-implement, cost-effective intervention with a potential payoff that includes better developmental outcomes, more optimal behavior, and fewer rehospitalizations," the authors conclude.

The authors have disclosed no relevant financial relationships.

Pediatrics. 2006;118:e115-e123.