Day-care, Early Common Infections and Childhood Acute Leukaemia: A Multicentre French Case-Control Study

Br J Cancer. 2002 Apr 8;86(7):1064-9. doi: 10.1038/sj.bjc.6600091.

Abstract

We conducted a case-control study to investigate the role of early infections in the aetiology of childhood acute leukaemias. The study included 280 incident cases (240 acute lymphoblastic leukaemia and 40 acute non-lymphoblastic leukaemia) and 288 hospital controls, frequency matched by age, gender, hospital, catchment area of the hospital and ethnic origin. Data were obtained from standardised face-to-face interviews of the mothers. The interviews included questions on early common infections, day-care attendance, breast-feeding, birth order and infantile diseases. Odds ratios were estimated using an unconditional regression model including the stratification variables, parental socio-economic status and perinatal characteristics. Birth order was not associated with childhood leukaemia (acute lymphoblastic or acute non-lymphoblastic). A statistically-significant inverse association was observed between childhood leukaemia and day-care attendance (odds ratio=0.6, 95% Confidence Interval=(0.4-1.0)), repeated early common infections (> or = 4 per year before age two, odds ratio=0.6 (0.4-1.0)), surgical procedures for ear-nose-throat infections before age two (odds ratio=0.5 (0.2-1.0)) and prolonged breast-feeding (> or = 6 months, odds ratio=0.5 (0.2-1.0)). In the multivariate model including day-care attendance, early common infections and breast-feeding, results concerning breast-feeding remained unchanged. A statistically significant interaction between day-care attendance and repeated early common infections was observed. When the interaction was taken into account, the simple effects of day-care and early common infections disappeared (odds ratio=1.1 (0.5-2.3) and odds ratio=0.8 (0.5-1.3), respectively) while the joint effect of day-care attendance and early common infections was negatively associated with childhood leukaemia (odds ratio=0.3 (0.1-0.8)). All the above associations were observed both for acute lymphoblastic leukaemia and acute non-lymphoblastic leukaemia. Our results support Greaves' hypothesis, even though they are not specific of common leukaemia.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Breast Feeding*
  • Case-Control Studies
  • Child
  • Child Day Care Centers*
  • Child, Preschool
  • Female
  • France / epidemiology
  • Humans
  • Infant
  • Infant, Newborn
  • Infections*
  • Leukemia, Myeloid, Acute / epidemiology
  • Leukemia, Myeloid, Acute / etiology*
  • Leukemia, Myeloid, Acute / prevention & control*
  • Male
  • Odds Ratio
  • Precursor Cell Lymphoblastic Leukemia-Lymphoma / epidemiology
  • Precursor Cell Lymphoblastic Leukemia-Lymphoma / etiology*
  • Precursor Cell Lymphoblastic Leukemia-Lymphoma / prevention & control*
  • Risk Factors