Childhood cancer mortality and socioeconomic position in South Korea: a national population-based birth cohort study

Cancer is among the leading causes of death in children, and the influence of socioeconomic inequalities on childhood cancer is an important public health concern. We examined the relationship of socioeconomic position with childhood cancer mortality in South Korea. A retrospective cohort study of South Koreans was conducted using data from the national birth register collected between 1995 and 2006, which was individually linked to mortality data. A cohort of 6,479,406 children was followed from birth until their death or through December 31, 2006. Poisson regression analysis was used to estimate the rate ratios of childhood cancer death according to socioeconomic position. A total of 1,469 cancer deaths were observed during the study period. We found significantly increased cancer mortality to be associated with the educational level of mother (RR = 1.56, 95% CI 1.27-1.91) and father (RR = 1.39, 95% CI 1.15-1.70) in middle school graduate or below compared with those of college graduate or higher. The risks of cancer death increased among children born with fathers outside the workforce (RR = 1.36, 95% CI 1.09-1.69) and with mothers engaged in manual work (RR = 1.41, 95% CI 1.03-1.92), when compared with those of non-manual counterparts. Children born in rural areas showed significantly increased risk of death from cancer. We concluded that in South Korea, there were inequalities in childhood cancer mortality by socioeconomic position.