title: Epidemiology of severe hearing impairment in a population-based cerebral palsy cohort.
abstract: BACKGROUND
  Comorbidities including hearing impairment occur commonly in individuals with cerebral palsy (CP).
  
  
  METHODS
  Hearing impairment was assessed in a registry-derived population-based sample of children with CP.
  
  
  RESULTS
  Hearing impairment was documented in 12.7% (27 of 212) with less than a quarter of these (or 2.7% overall [6 of 212]) having a severe hearing loss of greater than 70 dB bi-aurally. Those with severe hearing impairment were more likely to be nonambulatory (Gross Motor Function Classification System IV/V; 100% versus 34.0% in the registry; P < 0.001) and have a spastic quadriplegic or dyskinetic CP variant (100% versus 42%, P = 0.001). Severe neonatal hyperbilirubinemia necessitating exchange transfusion demonstrated a striking association with hearing impairment in the context of CP in spite of small observed numbers; three of three had severe hearing loss, accounting for 50% of cases of severe hearing loss.
  
  
  CONCLUSIONS
  These results suggest a specific CP context and antecedent conditions that necessitate a heightened vigilance for the detection and remediation of hearing impairment.
authors.affiliation: Division of Pediatric Neurology, Montreal Children's Hospital, Department of Pediatrics, McGill University, Montreal, Quebec, Canada.
authors.forename: David
authors.initials: D
authors.lastname: Dufresne
authors.affiliation: Division of Pediatric Neurology, Montreal Children's Hospital, Department of Pediatrics, McGill University, Montreal, Quebec, Canada.
authors.forename: Lynn
authors.initials: L
authors.lastname: Dagenais
authors.affiliation: Division of Pediatric Neurology, Montreal Children's Hospital, Department of Pediatrics, McGill University, Montreal, Quebec, Canada. Electronic address: michael.shevell@muhc.mcgill.ca.
authors.forename: Michael I
authors.initials: MI
authors.lastname: Shevell
mesh_terms: D000293:Adolescent; D002547:Cerebral Palsy / Q000150:complications*; D002648:Child; D015331:Cohort Studies; D005260:Female; D034381:Hearing Loss / Q000453:epidemiology* / Q000209:etiology*; D006801:Humans; D008297:Male; D011792:Quebec / Q000453:epidemiology; D012042:Registries
keywords: CP; epidemiology; hearing loss; population-based registry