title: Invited commentary: childhood acute lymphoblastic leukemia and allergies: biology or bias?
abstract: Previous epidemiologic studies have shown an inverse association between a personal history of atopy/allergies, both overall and among asthma, eczema, and hay fever investigated separately, and childhood acute lymphoblastic leukemia (ALL) with some consistency; however, in most of these studies, exposure data were collected by maternal interview. Now, in a population-based and records-based study in this issue of the Journal (Am J Epidemiol. 2012;176(11):970-978), Chang et al. report an increased risk for allergic conditions across different etiologic time periods, calling the former paradigm into doubt. A review of the basic biology literature shows that proposed mechanisms support either a positive or an inverse association. In light of this ambiguity, it is epidemiology's turn to determine the direction of association.
authors.affiliation: Division of Pediatric Epidemiologyand Clinical Research, Department of Pediatrics, University of Minnesota, Minneapolis, Minnesota 55455, USA. linabery@umn.edu
authors.forename: Amy M
authors.initials: AM
authors.lastname: Linabery
authors.forename: Logan G
authors.initials: LG
authors.lastname: Spector
mesh_terms: D005260:Female; D006801:Humans; D006967:Hypersensitivity / Q000276:immunology*; D008297:Male; D054198:Precursor Cell Lymphoblastic Leukemia-Lymphoma / Q000276:immunology*