title: Head circumference at birth and risk of brain cancer in childhood: a population-based study.
abstract: BACKGROUND
  Studies have found only a weak or no association between birthweight and brain cancer in childhood. However, previous studies have not assessed the association between head circumference at birth and brain cancer. We aimed to assess the risk of brain cancer in childhood according to head circumference at birth.
  
  
  METHODS
  We investigated the association between incidence of brain cancer in childhood and factors recorded at birth such as head circumference, birthweight, and gestational age based on the Norwegian medical birth registry from 1978-98, linked to the Norwegian cancer registry from 1978-2002.
  
  
  RESULTS
  We analysed 1,010,366 individuals with 12,378,172 person-years of follow-up, from which 453 individuals aged 0-15 years were diagnosed with brain cancer. The relative risk of brain cancer was 1.27 (95% CI 1.16-1.38) per 1-cm increase in head circumference after adjustment for birthweight, gestational age, and sex.
  
  
  CONCLUSIONS
  Head circumference is positively associated with incidence of brain cancer in childhood, suggesting that brain pathology originates during fetal life.
authors.affiliation: Department of Epidemiology, Norwegian Institute of Public Health, Oslo, Norway. osamuels@math.uio.no
authors.forename: Sven Ove
authors.initials: SO
authors.lastname: Samuelsen
authors.forename: Leiv S
authors.initials: LS
authors.lastname: Bakketeig
authors.forename: Steinar
authors.initials: S
authors.lastname: Tretli
authors.forename: Tom B
authors.initials: TB
authors.lastname: Johannesen
authors.forename: Per
authors.initials: P
authors.lastname: Magnus
mesh_terms: D000293:Adolescent; D001921:Brain / Q000254:growth & development; D001932:Brain Neoplasms / Q000453:epidemiology* / Q000209:etiology*; D002508:Cephalometry; D002648:Child; D002675:Child, Preschool; D016021:Epidemiologic Studies; D005260:Female; D006801:Humans; D015994:Incidence; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D009664:Norway / Q000453:epidemiology; D012042:Registries / Q000706:statistics & numerical data; D012307:Risk Factors