Human milk to protect from necrotizing enterocolitis or death in extremely low birth weight infants

Necrotizing enterocolitis (NEC) is the most significant gastrointestinal emergency occurring among very low birth weight infants. NEC represents a major cause of morbidity and mortality, and is widespread among very low birth weight infants (incidence 7-13%); the disease is more frequent in extremely low birth weight infants. Human milk (HM) feeding is recommended by the American Academy of Pediatrics. HM reduces the risk for NEC in premature infants, even if the mechanism of protection is not completely understood. In addition, HM may reduce rates of late onset sepsis, and retinopathy of prematurity, and could have long-term effects on the cognitive development of extremely premature infants.
An American group have conducted a study to determine the association between amount of HM taken in the first weeks of life and subsequent risk of the combined outcome of NEC or death.
This analysis was conducted on 1272 infants (birth weight: 401-1000g) previously included in the National Institute of Child Health and Human Development Neonatal Network Glutamine Trial. HM intake was defined as the proportion of HM to total intake, to enteral intake and total volume over the first 14 days.
Results show that 13.6% of the infants died or developed NEC after 14 days. The likelihood of NEC or death after 14 days was decreased by a factor of 0.83 (95% confidence interval, CI 0.72-0.96) for each 10% increase in the proportion of HM to total intake. Each 100 ml/kg increase in HM intake during the first 14 days was associated with decreased risk of NEC or death (hazard ratio 0.87; 95% CI 0.77-0.97). A trend towards a decreased risk of NEC or death among infants who received 100% HM as a proportion to total enteral intake (HM plus formula) was reported, although this finding was not statistically significant.
Overall, these findings support a possible dose-dependent, beneficial effect of HM on risk of NEC or death in extremely low birth weight infants. These results are consistent with previous observational studies. Therefore, the pool of evidence suggesting an inverse relationship between the cumulative amount of HM an infant received and the subsequent risk of NEC or death is further confirmed and expanded. An association between receipt of any type of enteral feeding, including but not limited to HM, and reduced risk of NEC or death was also observed. However, this study did not distinguish the effects of willingness of clinicians to provide enteral feedings, the infant's ability to tolerate enteral feedings, the mother's intention to breast-feed and the type of enteral feeding used.
In conclusion, a recommendation to encourage HM feeding to prevent NEC can be supported by evidence found in this study as well as in other trials. These results, and absence of evidence of harm associated with HM feedings, can be used to guide mothers' infant feeding decisions and NICU policies that encourage provision of HM to premature infants.

Top