Birth Characteristics, Sibling Patterns, and Acute Leukemia Risk in Childhood: a Population-Based Cohort Study

Abstract

The association between birth weight and childhood leukemia suggests the importance of intrauterine factors. A plausible explanation may be that increasing birth weight is associated with a higher rate of cell proliferation and/or a larger number of precursor cells being at risk of malignant transformation. The inverse association between birth order and ALL risk among 0-4 year olds was weak, but it was compatible with the hypothesis that delayed exposure to infection may increase the risk of ALL in this age group. The association of childhood AML with birth order and sibship size at young ages deserves further attention in the search for environmental factors that affect childhood AML risk.

Association of early life factors and acute lymphoblastic leukaemia in childhood: historical cohort study

“…This sensitivity to the choice of threshold may suggest that the association is spurious. On the other hand, we displayed the same relationship, and a similar magnitude of effect, as one other population-based cohort (Westergaard et al, 1997). The relationship is also biologically plausible and evidence is accumulating to suggest that it may be mediated through IGF-1 (Ross et al, 1996;Yeazel et al, 1997;Petridou et al, 1999;Blatt, 2000;Eshet et al, 2000).…”

“…We did find any association with maternal age. Paternal age has been infrequently examined as a risk factor for childhood ALL, with reports of both a positive association (Kaye et al, 1991) and no association (Shaw et al, 1984;Westergaard et al, 1997;Hemminki et al, 1999). We demonstrated a strong relationship between ALL and paternal age of 35 years or more.…”

“…To date, the findings on birth weight and risk of childhood leukaemia have been inconsistent. Several studies have reported positive relationships with ALL (Robison et al, 1987;Kaye et al, 1991;Westergaard et al, 1997) while others (McKinney et al, 1987(McKinney et al, , 1999Roman et al, 1997;Dockerty et al, 1999), found no association or a relationship with both high and low birth weight (Schuz et al, 1999). It is possible that selection bias, particularly among controls, may have resulted in the failure of some investigators to observe a positive association as controls are likely to be of higher socio-economic position and thus have infants of higher average birth weight, than the general population (Kogan, 1995).…”

“…Recently there has been growing interest in the relationship between prenatal and early life influences on risk of childhood leukaemia (Van Steensel-Moll et al, 1985;Shu et al, 1988;Kaye et al, 1991;Westergaard et al, 1997;McKinney et al, 1999). It is clear that mutations occurring in-utero in lymphoid stem cells contribute to the development of childhood leukaemia (Greaves, 1999;Wiemels et al, 1999) but it is not known which prenatal exposures result in these mutations or how they may be prevented.…”

“…Study designs utilized to date may have contributed to this lack of consistency and very few population-based cohort studies of childhood leukaemia have been performed (Westergaard et al, 1997;Mogren et al, 1999). We describe a population-based cohort study, undertaken in Northern Ireland, which includes unique information recorded at birth on socio-economic position and living conditions in the household.…”