title: Factors associated with developing cholesteatoma: a study of 45,980 children with middle ear disease.
abstract: OBJECTIVE
  To identify factors associated with the rate of developing cholesteatoma following ventilation tube insertion (VTI).
  
  
  METHODS
  A population-based retrospective cohort study.
  
  
  METHODS
  Administrative health data from all private and public hospitals in Western Australia for children who had at least one VTI from 1980 to 2004 was used to identify subsequent hospital admissions for cholesteatoma. Main outcome measures were time to cholesteatoma (survival) outcomes, including hazard ratios, log-rank tests, and Kaplan-Meier failure functions.
  
  
  RESULTS
  There were 45,980 children who underwent at least one VTI from 1980 to 2004 with 460 subsequently developing cholesteatoma. The cumulative percentage of children who developed cholesteatoma within 15 years after one VTI procedure was 0.9% (95% confidence interval [CI], 0.8-1.0), after two VTIs 2.1% (95% CI, 1.6-2.3), after three VTIs 3.8% (95% CI, 2.9-4.8), and after four or more VTIs 5.2% (95% CI, 4.0-6.7). The rate of developing cholesteatoma increased 10% (95% CI, 6-14) for each additional year in age before first VTI. For children who underwent two or more VTIs, the rate of cholesteatoma increased 21% (95% CI, 12-32) with each additional year between VTIs. Adenoid removal was associated with a 27% (95% CI, 11-40) reduction in the rate of developing cholesteatoma.
  
  
  CONCLUSIONS
  Children with persistent or refractory middle ear disease who required multiple VTIs were at increased risk of cholesteatoma. First ventilation tubes inserted at an early age, subsequent ventilation tubes inserted without delay, and adenoid removal were associated with a reduced rate of cholesteatoma development.
authors.affiliation: Centre for Population Health Research, Curtin Health Innovation Research Institute, Curtin University of Technology, Perth, Australia. katrina.spilsbury@curtin.edu.au
authors.forename: Katrina
authors.initials: K
authors.lastname: Spilsbury
authors.forename: Ian
authors.initials: I
authors.lastname: Miller
authors.forename: James B
authors.initials: JB
authors.lastname: Semmens
authors.forename: Francis J
authors.initials: FJ
authors.lastname: Lannigan
mesh_terms: D000367:Age Factors; D002648:Child; D002675:Child, Preschool; D018424:Cholesteatoma, Middle Ear / Q000453:epidemiology / Q000209:etiology*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007223:Infant; D008297:Male; D008390:Markov Chains; D008876:Middle Ear Ventilation / Q000009:adverse effects*; D016016:Proportional Hazards Models; D012307:Risk Factors; D016019:Survival Analysis; D014904:Western Australia / Q000453:epidemiology