title: The epidemiology of childhood cardiomyopathy in Australia.
abstract: BACKGROUND
  The incidence and age distribution of primary cardiomyopathy in children are not well defined. We undertook a population-based, retrospective cohort study in Australia to document the epidemiology of childhood cardiomyopathy.
  
  
  METHODS
  We analyzed all cases of primary cardiomyopathy in children who presented between 1987 and 1996 and who were younger than 10 years of age. Children were recruited from multiple sources, and cases of cardiomyopathy were classified according to World Health Organization guidelines.
  
  
  RESULTS
  Over the 10-year period, 314 new cases of primary cardiomyopathy were identified, for an annual incidence of 1.24 per 100,000 children younger than 10 years of age (95 percent confidence interval, 1.11 to 1.38). Dilated cardiomyopathy made up 58.6 percent of cases, hypertrophic cardiomyopathy 25.5 percent, restrictive cardiomyopathy 2.5 percent, and left ventricular noncompaction 9.2 percent of cases. The incidence of all types of cardiomyopathy except restrictive declined rapidly after infancy. In 11 cases (3.5 percent), sudden death was the first symptom. There was a male predominance among children with hypertrophic and unclassified cardiomyopathy. Indigenous children had a higher incidence of dilated cardiomyopathy than nonindigenous children (relative risk, 2.67; 95 percent confidence interval, 1.42 to 4.63) and a higher rate of death as the presenting symptom (16.7 percent vs. 2.6 percent, P=0.02). Lymphocytic myocarditis was present in 25 of 62 children with dilated cardiomyopathy (40.3 percent) who underwent cardiac histologic examination within two months after presentation.
  
  
  CONCLUSIONS
  Lymphocytic myocarditis and left ventricular noncompaction are important causes of childhood cardiomyopathy in Australia. The timing and severity of presentation in children with cardiomyopathy are related to the type of cardiomyopathy, as well as to genetic and ethnic factors.
authors.affiliation: Departments of Cardiology, Royal Children's Hospital, Melbourne, Australia.
authors.forename: Alan W
authors.initials: AW
authors.lastname: Nugent
authors.forename: Piers E F
authors.initials: PE
authors.lastname: Daubeney
authors.forename: Patty
authors.initials: P
authors.lastname: Chondros
authors.forename: John B
authors.initials: JB
authors.lastname: Carlin
authors.forename: Michael
authors.initials: M
authors.lastname: Cheung
authors.forename: Lynette C
authors.initials: LC
authors.lastname: Wilkinson
authors.forename: Andrew M
authors.initials: AM
authors.lastname: Davis
authors.forename: Stephen G
authors.initials: SG
authors.lastname: Kahler
authors.forename: C W
authors.initials: CW
authors.lastname: Chow
authors.forename: James L
authors.initials: JL
authors.lastname: Wilkinson
authors.forename: Robert G
authors.initials: RG
authors.lastname: Weintraub
mesh_terms: D017677:Age Distribution; D001315:Australia / Q000453:epidemiology; D009202:Cardiomyopathies / Q000453:epidemiology* / Q000208:ethnology / Q000209:etiology; D002648:Child; D002675:Child, Preschool; D015331:Cohort Studies; D005260:Female; D006801:Humans; D015994:Incidence; D007223:Infant; D008214:Lymphocytes; D008297:Male; D009205:Myocarditis / Q000150:complications / Q000276:immunology; D012189:Retrospective Studies; D017678:Sex Distribution