IS H2 blocker therapy associated with NEC in VLBW infants?

The answer to this question appears to be "Yes," according to a study in very low birthweight infants (VLBW) who developed necrotizing enterocolitis (NEC). Investigators analyzed data from the National Institute of Child Health and Human Development Neonatal Research Network very low birthweight (401-1,500 g) registry. Of 11,072 infants who survived for at least 12 hours, the 787 (7.1%) who developed NEC were the subject of the study.

Investigators used case-control methodology to determine the relation between a diagnosis of NEC and preceding H₂-blocker treatment. They matched three controls to each NEC case based on birthweight category (401-750 g, 751-1,000 g, 1,001-1,250 g, and 1,251-1,500 g), race, and the center in which the infant was cared for-all factors highly associated with the likelihood of NEC. Development of NEC was associated with H₂-blocker therapy, using ranitidine, famotidine, or cimetidine. In addition, infants with NEC were more likely to be black, of lower birthweight, and to have been born outside the treating hospital. Both the incidence of NEC and the frequency with which infants were treated with H₂-blockers at any time during their hospitalization varied by clinical center (Guillet R et al: Pediatrics 2006; 117:e137).

Commentary The authors point out that little evidence exists for much of the H₂-blocker use for gastroesophageal reflux and stress ulcer prevention in the neonatal intensive care unit (or elsewhere). It is hard to justify this use if it may be linked to development of NEC: Evidence-based medicine meets "first do no harm."