title: Vitamin supplement use among children with Down's syndrome and risk of leukaemia: a Children's Oncology Group (COG) study.
abstract: Vitamin supplements have been proposed for children with Down's syndrome (DS) with claims of improving cognitive abilities, or immune or thyroid function. Several studies have shown decreased levels of zinc in this population. Because children with DS have a 50-fold increased risk of developing acute leukaemia during the first 5 years of life, we explored the relation between child vitamin and herbal supplement use and the risk of leukaemia in a case-control study. During the period 1997-2002, we enrolled 158 children with DS aged 0-18 years that were diagnosed with acute lymphoblastic leukaemia (ALL) (n = 97) or acute myeloid leukaemia (AML) (n = 61) at participating Children's Oncology Group institutions. We enrolled 173 DS children without leukaemia (controls), selected from the cases' primary care clinic and frequency-matched on age. Data were collected via telephone interviews with mothers of the index child regarding use of multivitamins, zinc, vitamin C, iron and herbal supplements, including age at first use, frequency and duration. Among controls, 57% reported regular multivitamin use (>/=3 times/week for >/=3 months) compared with 48% of ALL cases and 61% of AML cases. We found no evidence of an association between children's regular multivitamin use and ALL or AML (adjusted odds ratios [OR] = 0.94 [95% CI 0.52, 1.70] and 1.90 [0.73, 4.91] respectively). There was a suggestion of an increased risk for AML associated with regular multivitamin use during the first year of life or for an extended duration (ORs = 2.38 [0.94, 5.76] and 2.59 [1.02, 6.59] respectively). Despite being the largest study of DS-leukaemia, our sample size was small, resulting in imprecise effect estimates. Future research should include larger sample sizes as well as a full assessment of diet including vitamin supplementation to adequately examine the relation between nutritional status and childhood leukaemia.
authors.affiliation: University of Minnesota Cancer Center, Division of Pediatric Epidemiology and Clinical Research, Department of Pediatrics, University of Minnesota, Minneapolis, MN 55455, USA.
authors.forename: Cindy K
authors.initials: CK
authors.lastname: Blair
authors.forename: Michelle
authors.initials: M
authors.lastname: Roesler
authors.forename: Yang
authors.initials: Y
authors.lastname: Xie
authors.forename: Alan S
authors.initials: AS
authors.lastname: Gamis
authors.forename: Andrew F
authors.initials: AF
authors.lastname: Olshan
authors.forename: Nyla A
authors.initials: NA
authors.lastname: Heerema
authors.forename: Leslie L
authors.initials: LL
authors.lastname: Robison
authors.forename: Julie A
authors.initials: JA
authors.lastname: Ross
mesh_terms: D000293:Adolescent; D000328:Adult; D016022:Case-Control Studies; D002648:Child; D002675:Child, Preschool; D019587:Dietary Supplements / Q000009:adverse effects / Q000706:statistics & numerical data*; D004314:Down Syndrome / Q000150:complications / Q000188:drug therapy*; D005260:Female; D006801:Humans; D007223:Infant; D015470:Leukemia, Myeloid, Acute / Q000453:epidemiology / Q000209:etiology; D008297:Male; D054198:Precursor Cell Lymphoblastic Leukemia-Lymphoma / Q000453:epidemiology* / Q000209:etiology; D012307:Risk Factors; D014815:Vitamins / Q000009:adverse effects
chemical_list: D014815:Vitamins