title: Necrotizing enterocolitis among neonates in the United States.
abstract: BACKGROUND
  Prior studies have identified individual risk factors that are associated with necrotizing enterocolitis (NEC); however, the small sample sizes of these previous studies have not allowed the analysis of potential interaction between multiple variables and NEC. Our purpose was to describe the incidence and risk factors for NEC in premature neonates admitted for intensive care.
  
  
  METHODS
  We identified neonates as having NEC if they met accepted diagnostic criterion for necrotizing enterocolitis. Using a national database, we assessed the association between NEC and a battery of risk factors previously reported in peer-reviewed literature.
  
  
  RESULTS
  There were 15,072 neonates that met inclusion criteria; 14,682 did not have NEC, while 390 (2.6%) met criterion for NEC. Multivariate analysis showed that low birth weight was the most important risk factor for NEC. Other factors that were associated with an increased risk of NEC were exposure to antenatal glucocorticoids, vaginal delivery, need for mechanical ventilator support, exposure to both glucocorticoids and indomethacin during the first week of life, absence of an umbilical arterial catheter, and low Apgar score at 5 minutes. Length of hospital stay and mortality were higher in neonates with NEC than in neonates without NEC.
  
  
  CONCLUSIONS
  NEC remains an important cause of morbidity and mortality in prematurely born neonates. In contrast to previous studies, we found that exposure to antenatal glucocorticoids was associated with an increased risk for NEC independent of birth weight.
authors.affiliation: Division of Neonatology, Department of Pediatrics, University of Tennessee College of Medicine, Chattanooga Unit, USA.
authors.forename: Scott O
authors.initials: SO
authors.lastname: Guthrie
authors.forename: Phillip V
authors.initials: PV
authors.lastname: Gordon
authors.forename: Victor
authors.initials: V
authors.lastname: Thomas
authors.forename: James A
authors.initials: JA
authors.lastname: Thorp
authors.forename: Joyce
authors.initials: J
authors.lastname: Peabody
authors.forename: Reese H
authors.initials: RH
authors.lastname: Clark
mesh_terms: D001724:Birth Weight; D020345:Enterocolitis, Necrotizing / Q000453:epidemiology* / Q000209:etiology* / Q000628:therapy; D005260:Female; D005865:Gestational Age; D006801:Humans; D015994:Incidence; D007226:Infant Mortality; D007231:Infant, Newborn; D007234:Infant, Premature; D007363:Intensive Care Units, Neonatal / Q000706:statistics & numerical data; D008297:Male; D017063:Outcome Assessment, Health Care; D012189:Retrospective Studies; D012307:Risk Factors; D014481:United States / Q000453:epidemiology