Is the risk of childhood leukaemia associated with socioeconomic measures in Denmark? A nationwide register‐based case‐control study

Abstract

The aetiology of childhood leukaemia is poorly understood. Knowledge about differences in risk by socioeconomic status (SES) may enhance etiologic insights. We conducted a nationwide register‐based case‐control study to evaluate socioeconomic differences in the risk of childhood leukaemia in Denmark and to access whether associations varied by different measures of SES, time point of assessment, leukaemia type and age at diagnosis. We identified all cases of leukaemia in children aged 0 to 19 years, born and diagnosed between 1980 and 2013 from the Danish Cancer Registry (N = 1336) and sampled four individually matched controls per case (N = 5330). We used conditional logistic regression models for analysis. Medium and high level of parental education was associated with a higher risk of acute myeloid leukaemia (AML) in the offspring, mainly driven by children diagnosed at ages 0 to 4 years [odds ratio (OR) for high maternal education = 3.07; 95% confidence interval (CI): 1.44‐6.55]. We also observed a modestly increased risk for lymphoid leukaemia (LL) in association with higher level of parental education, but only in children diagnosed at ages 5 to 19 years. Higher parental income was associated with an increased risk of LL but not AML among children aged 5 to 19 years at diagnosis (OR for high maternal income = 2.78; 95% CI: 1.32‐5.89). Results for neighbourhood SES measures indicated null associations. Bias or under‐ascertainment of cases among families with low income or basic education are unlikely to explain the observed socioeconomic differences. Future research addressing explicitly the underlying mechanisms of our results may help to enhance etiologic insights of the disease.

Incidence of childhood leukemia before and after shut down of nuclear power plants in Germany in 2011: A population‐based register study during 2004 to 2019

“…While most international studies reported evidence of an association between SES and childhood leukemia risk, the observed direction of the association was heterogeneous. Generally, higher SES was associated with higher risk, but rarely also inverse associations were reported 20‐23 . In the absence of consistent and pertinent evidence, we did not adjust our analysis by SES.…”

“…Generally, higher SES was associated with higher risk, but rarely also inverse associations were reported. [20][21][22][23] In the absence of consistent and pertinent evidence, we did not adjust our analysis by SES.…”

Neighborhood Deprivation, Indoor Chemical Concentrations, and Spatial Risk for Childhood Leukemia

“…For example, geographic differences in socioeconomic status (SES) could be related to the risk of childhood leukemia. Neighborhood SES has been studied for many health outcomes, including childhood leukemia [ 17 , 18 , 19 , 20 , 21 , 22 ]. Area deprivation was not found to be associated with acute lymphoblastic leukemia (ALL) [ 22 ], and childhood leukemia was also not associated with area SES in some studies [ 19 , 20 ].…”

“…Neighborhood SES has been studied for many health outcomes, including childhood leukemia [ 17 , 18 , 19 , 20 , 21 , 22 ]. Area deprivation was not found to be associated with acute lymphoblastic leukemia (ALL) [ 22 ], and childhood leukemia was also not associated with area SES in some studies [ 19 , 20 ]. However, lowest area SES was found to be associated with lower ALL risk compared with highest area SES [ 21 ], and childhood leukemia incidence in England and Wales was higher in relatively affluent communities [ 18 ].…”