Format

Send to

Choose Destination
See comment in PubMed Commons below
Int J Epidemiol. 2010 Jun;39(3):718-32. doi: 10.1093/ije/dyp378. Epub 2010 Jan 27.

A meta-analysis of the association between day-care attendance and childhood acute lymphoblastic leukaemia.

Author information

1
School of Public Health, University of California, Berkeley, CA 94720, USA. urayamak@fellows.iarc.fr

Abstract

BACKGROUND:

Childhood acute lymphoblastic leukaemia (ALL) may be the result of a rare response to common infection(s) acquired by personal contact with infected individuals. A meta-analysis was conducted to examine the relationship between day-care attendance and risk of childhood ALL, specifically to address whether early-life exposure to infection is protective against ALL.

METHODS:

Searches of the PubMed database and bibliographies of publications on childhood leukaemia and infections were conducted. Observational studies of any size or location and published in English resulted in the inclusion of 14 case-control studies.

RESULTS:

The combined odds ratio (OR) based on the random effects model indicated that day-care attendance is associated with a reduced risk of ALL [OR = 0.76, 95% confidence interval (CI): 0.67, 0.87]. In subgroup analyses evaluating the influence of timing of exposure, a similarly reduced effect was observed for both day-care attendance occurring early in life (< or =2 years of age) (OR = 0.79, 95% CI: 0.65, 0.95) and day-care attendance with unspecified timing (anytime prior to diagnosis) (OR = 0.81, 95% CI: 0.70, 0.94). Similar findings were observed with seven studies in which common ALL were analysed separately. The reduced risk estimates persisted in sensitivity analyses that examined the sources of study heterogeneity.

CONCLUSIONS:

This analysis provides strong support for an association between exposure to common infections in early childhood and a reduced risk of ALL. Implications of a 'hygiene'-related aetiology suggest that some form of prophylactic intervention in infancy may be possible.

Comment in

PMID:
20110276
PMCID:
PMC2878455
DOI:
10.1093/ije/dyp378
[Indexed for MEDLINE]
Free PMC Article
PubMed Commons home

PubMed Commons

0 comments
How to join PubMed Commons

    Supplemental Content

    Full text links

    Icon for Silverchair Information Systems Icon for PubMed Central
    Loading ...
    Support Center