Fetal growth and acute childhood leukemia: looking beyond birth weight.
The authors examined the relation between birth weight, intrauterine growth, and risk of childhood leukemia using population-based linked health data from Western Australia. A cohort of 576,593 infants born in 1980-2004 were followed from birth to diagnosis of acute lymphoblastic leukemia (ALL) (n = 243) or acute myeloid leukemia (AML) (n = 36) before their 15th birthday, death, or the end of follow-up (December 31, 2005). Data were analyzed using Cox regression. Risk of ALL was positively associated with the proportion of optimal birth weight--a measure of the appropriateness of fetal growth--particularly among children younger than 5 years; the hazard ratio for a 1-standard-deviation increase in proportion of optimal birth weight was 1.25 (95% confidence interval: 1.07, 1.47). Among children younger than 5 years not classified as having high birth weight (defined as >3,500 g, >3,800 g, and >4,000 g), a 1-unit increase in proportion of optimal birth weight was associated with an approximately 40% increase in ALL risk. This suggests that accelerated growth, rather than high birth weight per se, is involved in the etiology of ALL. These findings are consistent with a role for insulin-like growth factor I in the causal pathway. Findings for AML were inconclusive, probably because of small numbers.
Milne
Elizabeth
E
Telethon Institute for Child Health Research, Centre for Child Health Research, University of Western Australia, Perth, Western Australia. lizm@ichr.uwa.edu.au
Laurvick
Crystal L
CL
Blair
Eve
E
Bower
Carol
C
de Klerk
Nicholas
N
D000293:Adolescent; D001724:Birth Weight; D002648:Child; D002675:Child, Preschool; D004812:Epidemiologic Methods; D005260:Female; D047109:Fetal Development; D005865:Gestational Age; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D007334:Insulin-Like Growth Factor I / Q000378:metabolism; D015470:Leukemia, Myeloid, Acute / Q000209:etiology*; D008297:Male; D008498:Medical Record Linkage; D054198:Precursor Cell Lymphoblastic Leukemia-Lymphoma / Q000209:etiology*; D016016:Proportional Hazards Models; D012307:Risk Factors; D014904:Western Australia / Q000453:epidemiology
D007334:Insulin-Like Growth Factor I