title: Risk factors for elevation of ABR threshold in NICU-treated infants.
abstract: OBJECTIVE
  Several risk factors for hearing impairment among infants treated in the neonatal intensive care unit (NICU) have been reported, but there have been few studies that show the correlation strength between the risk factors in NICU-treated infants and hearing impairment in childhood. The aim of this study was to clarify the relationship between risk factors in NICU-treated infants and a deteriolation of auditory brainstem response (ABR) threshold in their childhood.
  
  
  METHODS
  One hundred one NICU-treated infants with ABR threshold of 50 dBnHL or more underwent 2nd ABR test at 20 months after delivery. Multiple regression analysis was performed with ABR threshold change as an objective variable and risk factors as explanatory variables.
  
  
  RESULTS
  Two ABR tests of the 101 infants resulted in that 7 showed an elevation of ABR threshold by 20 dB, 70 showed a drop of ABR threshold by 20 dB, and 24 showed no significant change. Multiple regression analysis revealed that the factors contributing to the elevation of ABR threshold were congenital diaphragmatic hernia, severe respiratory disease, and a high C-reactive protein (CRP) level.
  
  
  CONCLUSIONS
  In the infants treated in NICU, an incidence of ABR threshold of 50 dBnHL or more was 9.0%, and 6.9% of the infants with the ABR threshold abnormality showed a significant elevation of ABR threshold in their childhood. Factors significantly related to an elevation of ABR threshold were a history of congenital diaphragmatic hernia, severe respiratory disease, and elevation of CRP. In infants with such factors, periodical examination of hearing is required.
authors.affiliation: Department of Otorhinolaryngology, National Center for Child Health and Development, Tokyo, Japan. morimoto-n@ncchd.go.jp
authors.forename: Noriko
authors.initials: N
authors.lastname: Morimoto
authors.forename: Hidenobu
authors.initials: H
authors.lastname: Taiji
authors.forename: Keiko
authors.initials: K
authors.lastname: Tsukamoto
authors.forename: Yuji
authors.initials: Y
authors.lastname: Morimoto
authors.forename: Tomoo
authors.initials: T
authors.lastname: Nakamura
authors.forename: Tomoko
authors.initials: T
authors.lastname: Hommura
authors.forename: Yushi
authors.initials: Y
authors.lastname: Ito
mesh_terms: D001309:Auditory Threshold; D002097:C-Reactive Protein / Q000032:analysis; D016057:Evoked Potentials, Auditory, Brain Stem; D006548:Hernia, Diaphragmatic / Q000453:epidemiology; D065630:Hernias, Diaphragmatic, Congenital; D006801:Humans; D007231:Infant, Newborn; D007363:Intensive Care Units, Neonatal; D017084:Otoacoustic Emissions, Spontaneous; D011014:Pneumonia / Q000453:epidemiology; D011030:Pneumothorax / Q000453:epidemiology; D012044:Regression Analysis; D012307:Risk Factors
chemical_list: D002097:C-Reactive Protein