title: Patterns of exposure to infectious diseases and social contacts in early life and risk of brain tumours in children and adolescents: an International Case-Control Study (CEFALO).
abstract: BACKGROUND
  Infectious diseases and social contacts in early life have been proposed to modulate brain tumour risk during late childhood and adolescence.
  
  
  METHODS
  CEFALO is an interview-based case-control study in Denmark, Norway, Sweden and Switzerland, including children and adolescents aged 7-19 years with primary intracranial brain tumours diagnosed between 2004 and 2008 and matched population controls.
  
  
  RESULTS
  The study included 352 cases (participation rate: 83%) and 646 controls (71%). There was no association with various measures of social contacts: daycare attendance, number of childhours at daycare, attending baby groups, birth order or living with other children. Cases of glioma and embryonal tumours had more frequent sick days with infections in the first 6 years of life compared with controls. In 7-19 year olds with 4+ monthly sick day, the respective odds ratios were 2.93 (95% confidence interval: 1.57-5.50) and 4.21 (95% confidence interval: 1.24-14.30).
  
  
  CONCLUSIONS
  There was little support for the hypothesis that social contacts influence childhood and adolescent brain tumour risk. The association between reported sick days due to infections and risk of glioma and embryonal tumour may reflect involvement of immune functions, recall bias or inverse causality and deserve further attention.
authors: Danish Cancer Society Research Center, Danish Cancer Society, Strandboulevarden 49, Copenhagen 2100, Denmark. veje@cancer.dk
authors: T V
authors: TV
authors: Andersen
authors: L S
authors: LS
authors: Schmidt
authors: A H
authors: AH
authors: Poulsen
authors: M
authors: M
authors: Feychting
authors: M
authors: M
authors: Röösli
authors: T
authors: T
authors: Tynes
authors: D
authors: D
authors: Aydin
authors: M
authors: M
authors: Prochazka
authors: B
authors: B
authors: Lannering
authors: L
authors: L
authors: Klæboe
authors: T
authors: T
authors: Eggen
authors: C E
authors: CE
authors: Kuehni
authors: K
authors: K
authors: Schmiegelow
authors: J
authors: J
authors: Schüz
mesh_terms: D000293:Adolescent; D000328:Adult; D001932:Brain Neoplasms / Q000453:epidemiology*; D016022:Case-Control Studies; D002648:Child; D005260:Female; D006801:Humans; D007239:Infections / Q000453:epidemiology*; D007398:Interpersonal Relations; D008297:Male; D012537:Scandinavian and Nordic Countries / Q000453:epidemiology; D013557:Switzerland / Q000453:epidemiology; D055815:Young Adult
references: Cancer Causes Control. 1996 Jul;7(4):437-48
references: 8813432
references: Oncogene. 2003 Aug 11;22(33):5181-91
references: 12910255
references: Br J Cancer. 2010 May 25;102(11):1670-5
references: 20461079
references: Prim Care. 2009 Dec;36(4):671-84
references: 19913181
references: Lancet Oncol. 2007 Aug;8(8):685-95
references: 17644483
references: Cancer Causes Control. 2009 Mar;20(2):129-36
references: 18766446
references: Oncogene. 2003 Aug 11;22(33):5164-72
references: 12910253
references: Nat Rev Cancer. 2006 Mar;6(3):193-203
references: 16467884
references: Br J Neurosurg. 1990;4(1):17-25
references: 2334522
references: Med Pediatr Oncol. 2003 Jan;40(1):26-34
references: 12426683
references: Neurology. 2006 Dec 12;67(11):1979-83
references: 17159104
references: Leukemia. 2008 Jan;22(1):189-93
references: 17690702
references: Cancer Causes Control. 2006 Dec;17(10):1267-74
references: 17111258
references: Dan Med Bull. 1997 Nov;44(5):535-9
references: 9408738
references: Cancer. 2007 Aug 15;110(4):703-13
references: 17620277
references: Acta Oncol. 2009;48(1):27-33
references: 18767000
references: Int J Epidemiol. 2003 Apr;32(2):248-56
references: 12714545
references: Br J Cancer. 1995 Jan;71(1):1-5
references: 7819022
references: Pediatrics. 2006 Oct;118(4):1439-46
references: 17015534
references: Am J Epidemiol. 2007 Mar 1;165(5):496-504
references: 17182983
references: J Natl Cancer Inst. 2011 Aug 17;103(16):1264-76
references: 21795665
references: Int J Cancer. 1998 Aug 12;77(4):498-503
references: 9679748
references: Pediatr Blood Cancer. 2008 Oct;51(4):468-74
references: 18454472
references: Acta Paediatr. 2009 Oct;98(10):1620-7
references: 19594464
references: Neuroepidemiology. 2003 Jul-Aug;22(4):249-54
references: 12792146
references: APMIS Suppl. 1992;31:1-194
references: 1301768
references: Br J Cancer. 1999 May;80(3-4):585-90
references: 10408870
references: Br J Cancer. 2006 Aug 7;95(3):416-22
references: 16868540
references: Br J Cancer. 2002 Sep 23;87(7):746-50
references: 12232758
references: Blood Cells Mol Dis. 2009 Mar-Apr;42(2):117-20
references: 19064328
references: Eur J Cancer. 2009 May;45(7):1218-1231
references: 19091545
references: Pediatr Pulmonol. 2008 Jun;43(6):584-93
references: 18435478
references: Br J Cancer. 1999 Aug;80(11):1844-51
references: 10468308
references: Pediatrics. 2001 May;107(5):E76
references: 11331726
references: J Clin Epidemiol. 2006 Apr;59(4):429-35
references: 16549266
references: J Clin Epidemiol. 1991;44(11):1159-66
references: 1941011
references: Expert Rev Neurother. 2002 Jul;2(4):469-79
references: 19810944
references: Pediatr Neurosurg. 2000 Jun;32(6):321-6
references: 10971194
references: Br J Cancer. 2002 May 6;86(9):1419-24
references: 11986774
references: Pediatr Blood Cancer. 2011 Jan;56(1):65-9
references: 21108441
references: Eur J Cancer. 2006 Sep;42(13):2064-80
references: 16919771