Maternal Dietary Intake of Folate and Vitamins B6 and B12 During Pregnancy and the Risk of Childhood Acute Lymphoblastic Leukemia

Abstract

Our aim was to address the hypothesis that maternal dietary intake of folate during pregnancy is inversely associated with risk of acute lymphoblastic leukemia (ALL) in the offspring. Dietary intake of folate, vitamins B6 and B12 in the last 6 mo of pregnancy from 333 cases and 695 frequency-matched controls were assessed using a food frequency questionnaire. Data were analyzed using unconditional logistic regression, adjusting for study matching variables, total energy, and potentially confounding variables. Higher levels of dietary folate and B12 appeared to be associated with a decreased risk of ALL. Higher levels of vitamin B6 were associated with an increased risk. The strongest associations of ALL with these variables were seen when mothers consumed alcohol in pregnancy. Our findings are consistent with a modest protective effect of higher dietary intake of folate and vitamin B12 against ALL in the offspring, more particularly among women who drank alcohol during pregnancy. These findings are consistent with previous reports of the protective effects of a maternal diet high in fruit, vegetables, and nondairy protein sources. The vitamin B6 findings are not consistent with evidence that it is a protective factor against other cancers, and may be a chance finding.

ACKNOWLEDGMENTS

The Aus-ALL consortium was funded by The National Health and Medical Research Council (NHMRC) Grant 254539. Helen Bailey was supported by NHMRC Post Graduate Scholarship 513934, Elizabeth Milne by NHMRC Career Development Award 513910. The Aus-ALL consortium conducted the study and the Telethon Institute for Child Health Research (TICHR), University of Western Australia, was the coordinating centre. Bruce K Armstrong (Sydney School of Public Health, Australia), Elizabeth Milne (TICHR), Frank M van Bockxmeer (Royal Perth Hospital, Australia), Michelle Haber (Children's Cancer Institute Australia, Australia), Rodney J Scott (University of Newcastle, Australia), John Attia (University of Newcastle, Australia), Murray D Norris (Children's Cancer Institute Australia, Australia), Carol Bower (TICHR), Nicholas H de Klerk (TICHR), Lin Fritschi (WA Institute for Medical Research, Australia), Ursula R Kees (TICHR), Margaret Miller (Edith Cowan University, Australia), Judith R Thompson (WA Cancer Registry, Australia) were the research investigators and Helen D Bailey (TICHR) was the project coordinator. The clinical investigators were Frank Alvaro (John Hunter Hospital, Newcastle, Australia); Catherine Cole (Princess Margaret Hospital for Children, Perth, Australia); Luciano Dalla Pozza (Children's Hospital at Westmead, Sydney, Australia); John Daubenton (Royal Hobart Hospital, Hobart, Australia); Peter Downie (Monash Medical Centre, Melbourne, Australia); Liane Lockwood, (Royal Children's Hospital, Brisbane, Australia); Maria Kirby (Women's and Children's Hospital, Adelaide, Australia); Glenn Marshall (Sydney Children's Hospital, Sydney, Australia); Elizabeth Smibert (Royal Children's Hospital, Melbourne, Australia); Ram Suppiah, (previously Mater Children's Hospital, Brisbane, Australia). The authors wish to acknowledge the contribution made by our clinical co-investigators and clinical research associates who recruited and cared for study patients at each participating hospital, and Mr. Peter Cosgrove for programming the estimation of dietary intake from the food frequency questionnaires. The authors also thank the parents and children who participated in Aus-ALL.