Blood levels of folate at birth and risk of childhood leukemia
Menée auprès de 357 cas et 405 témoins, cette étude américaine évalue l'association entre le niveau sanguin de folates à la naissance et le risque de leucémie pédiatrique
Background: A role for folate in cancer etiology has long been suspected due to folate's function as a cofactor in DNA methylation and maintenance of DNA synthesis. Previous case-control studies examining the association between risk of childhood acute lymphoblastic leukemia (ALL) and mothers' self-reported folate intake and supplementation have been inconclusive. Methods: We utilized a quantitative microbiologic assay to measure newborn folate concentrations in archived dried bloodspots collected at birth from 313 incident ALL cases, 44 incident acute myeloid leukemia (AML) cases, and 405 matched population-based controls. Results: Overall, we found no difference in hemoglobin-normalized newborn folate concentrations (HbFol, nmol/g) between ALL cases and controls (2.76 vs. 2.77, p=0.97) or between AML cases and controls (2.93 vs. 2.76, p=0.32). Null results persisted after stratification by both birth period (1982-94, 1995-98, and 1999-2002) to account for the start of folate fortification of grain products in the US, and by self-reported maternal pre-pregnancy supplement use. Similarly, no association was observed for major ALL subgroups. Conclusions: Our results do not support an association between birth folate concentrations and risk of childhood AML or major ALL subgroups. Impact: However, they do not rule out a role for folate through exposures after birth or in early stages of fetal development.