title: Sensorineural hearing loss in children: the association with Apgar score. A registry-based study of 392,371 children in Norway.
abstract: OBJECTIVE
  The causes of congenital permanent hearing loss in children are insufficiently understood. We studied the association of Apgar score 5 min after birth with sensorineural hearing loss diagnosed before the age of 5 years.
  
  
  METHODS
  We performed an epidemiological cohort study with data obtained by linkage between The Medical Birth Registry of Norway and the Norwegian County Registry of Children with Hearing Loss. Cases were 327 children born in Norway during the period 1978-1998 with sensorineural hearing loss. Controls were all children in Norway without sensorineural hearing loss born in the same counties and during the same period as the cases (n=392,044). The associations of Apgar score 5 min after birth with sensorineural hearing loss were estimated as odds ratios (OR) with 95% confidence intervals (CI) by applying logistic regression analyses.
  
  
  RESULTS
  Among children with sensorineural hearing loss 0.9% (3/327) had Apgar score<3, whereas that was true for 0.1% (304/392044) of children without hearing loss (p=0.001, chi square test). The aOR for sensorineural hearing loss was 7.5 [95% CI 2.3-, 24.2] comparing Apgar score<3 to Apgar score 10, after adjustment for birthweight and concurrent birth defects. Most children with sensorineural hearing loss (90%) had Apgar score>8 five minutes after birth.
  
  
  CONCLUSIONS
  Low Apgar score was associated with childhood sensorineural hearing loss. However, most children with sensorineural hearing loss, had Apgar score>8.
authors.affiliation: Division of Mental Health, Norwegian Institute of Public Health, 0403 Oslo, Norway. Electronic address: ellen.kvestad@fhi.no.
authors.forename: Ellen
authors.initials: E
authors.lastname: Kvestad
authors.affiliation: Division of Epidemiology, Norwegian Institute of Public Health, 0403 Oslo, Norway.
authors.forename: Kari Kveim
authors.initials: KK
authors.lastname: Lie
authors.affiliation: Department of Obstetrics and Gynecology and Institute of Clinical Medicine, Akershus University Hospital, 1478 Lørenskog, Norway; Division of Mental Health, Norwegian Institute of Public Health, 0403 Oslo, Norway.
authors.forename: Anne
authors.initials: A
authors.lastname: Eskild
authors.affiliation: Division of Mental Health, Norwegian Institute of Public Health, 0403 Oslo, Norway.
authors.forename: Bo
authors.initials: B
authors.lastname: Engdahl
mesh_terms: D001034:Apgar Score; D001724:Birth Weight; D002675:Child, Preschool; D015331:Cohort Studies; D005260:Female; D006319:Hearing Loss, Sensorineural / Q000453:epidemiology*; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D009664:Norway / Q000453:epidemiology; D016017:Odds Ratio; D012042:Registries
keywords: Apgar score; Childhood; Sensorineural hearing loss