Medically diagnosed infections and risk of childhood leukaemia: a population-based case–control study

Abstract

Background Previous studies on the association between childhood infections and childhood leukaemia have produced inconsistent results, likely due to the recall error/bias of infection data reported by the parents. The current study used a population-based and record-based case–control design to evaluate the association between childhood leukaemia and infections using the National Health Insurance Research Database of Taiwan. Methods In all, 846 childhood acute lymphoblastic leukaemia (ALL) and 193 acute myeloid leukaemia (AML) patients newly diagnosed between 2000 and 2008, aged >1 and 1 year before the cases’ diagnosis of childhood leukaemia. Conclusions Children with leukaemia may have a dysregulated immune function present at an early age, resulting in more episodes of symptomatic infections compared with healthy controls. However, confounding by other infectious measures such as birth order and day care attendance could not be ruled out. Finally, the results are only relevant to the medically diagnosed infections.