Impact of standardised feeding regimens on incidence of neonatal necrotising enterocolitis: a systematic review and meta-analysis of observational studies

BACKGROUND: A significant and prolonged decline in the incidence of necrotising enterocolitis (NEC), nearing virtual elimination in some centres, has been observed consistently since implementation of a standardised feeding regimen. AIM: To systematically review the observational studies reporting incidence of NEC in preterm, low birth weight (LBW) neonates "before" and "after" implementation of a standardised feeding regimen. METHODS: The Cochrane Central Register of Controlled Trials (CENTRAL, The Cochrane Library, Issue 4, 2002), Medline, Embase, Cinahl, and proceedings of the Pediatric Academic Societies (published in Pediatric Research from 1980) were searched in July and again in October 2003. The reference lists of identified observational studies, and personal files, were searched. No language restriction was applied. Key words were: standardised, enteral, feeding, neonates, necrotising enterocolitis. Authors were contacted for clarification of data. RESULTS: Six eligible studies (1978-2003) were identified. A significant heterogeneity was noted between the studies indicating the variations in the population characteristics and feeding practices over a period of 25 years. Meta-analysis of the six studies using a random effects model revealed a pooled risk ratio of 0.13 (95% confidence interval 0.03 to 0.50)-that is, introduction of a standardised feeding regimen reduced the incidence of NEC by 87%. CONCLUSION: Standardised feeding regimens may provide the single most important global tool to prevent/minimise NEC in preterm neonates. Randomised controlled trials are needed.