Birth weight and risk of childhood acute leukaemia.
ABSTRACT Studies of risk factors for acute leukaemia are inconclusive. This case-control study was done in West Azerbaijan province, Islamic Republic of Iran, to determine the relationship between birth weight and acute leukaemia in children aged under 15 years. For every patient 2 age- and sex-matched controls were selected from hospital and community populations. Of 130 cases diagnosed over the period 2003-2009,108 (83.1%) had lymphoblastic and 22 (16.9%) myloblastic type. Significantly more of them were male than female (55.4% versus 44.6%). In a multivariate logistic regression model variables significantly associated with acute leukaemia were: birth weight (OR = 2.25), birth order (OR = 2.25), birth place (OR = 7.93), history of chickenpox (OR = 0.46) and mothers' education (OR = 3.23). The risk of acute leukaemia increased significantly with increasing birth weight in the total group and among girls, but not among boys.
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ABSTRACT: Down syndrome (DS) is a common congenital anomaly, and children with DS have a substantially higher risk of leukemia. Although understanding of genetic and epigenetic changes of childhood leukemia has improved, the causes of childhood leukemia and the potential role of environmental exposures in leukemogenesis remain largely unknown. Although many epidemiologic studies have examined a variety of environmental exposures, ionizing radiation remains the only generally accepted environmental risk factor for childhood leukemia. Among suspected risk factors, infections, exposure to pesticides, and extremely low frequency magnetic fields are notable. While there are well-defined differences between leukemia in children with and without DS, studies of risk factors for leukemia among DS children are generally consistent with trends seen among non-DS (NDS) children. We provide background on DS epidemiology and review the similarities and differences in biological and epidemiologic features of leukemia in children with and without DS. We propose that both acute lymphoblastic and acute myeloblastic leukemia among DS children can serve as an informative model for development of childhood leukemia. Further, the high rates of leukemia among DS children make it possible to study this disease using a cohort approach, a powerful method that is unfeasible in the general population due to the rarity of childhood leukemia.Cancer Epidemiology 10/2014; DOI:10.1016/j.canep.2014.07.006 · 2.56 Impact Factor