J Korean Med Sci.  2023 Jan;38(2):e20. 10.3346/jkms.2023.38.e20.

Widening Social Inequalities in Cancer Mortality of Children Under 5 Years in Korea

• Son M
• Kim HR
• Choe SA
• Ki M
• Yong F
• Park M
• Paek D

• KMID: 2537952
• DOI: http://doi.org/10.3346/jkms.2023.38.e20

Abstract

Background
To investigate the effect of parental social class on cancer mortality in children under 5 in Korea, two birth cohorts were constructed by linking national birth data to under-5 death data from the Statistics Korea for 1995–1999 (3,323,613 births) and 2010–2014 (2,297,876 births).
Methods
The Cox proportional hazards model adjusted for covariates was used in this study.
Results
Social inequalities of under-5 cancer mortality risk in paternal education and paternal employment status were greater in 2010–2014 than in 1995–1999. The gap of hazard ratio (HR) of under-5 cancer mortality between lower (high school or below) and higher (university or higher) paternal education increased from 1.23 (95% confidence interval, 1.041.46) in 1995–1999 to 1.45 (1.11–1.97) in 2010–2014; the gap of HR between parents engaged in manual work and non-manual work increased from 1.32 (1.12–1.56) in 1995–1999 to 1.45 (1.12–1.89) in 2010–2014 for fathers, and from 1.18 (0.7–1.98) to 1.69 (1.03–2.79) for mothers. When the parental social class was lower, the risk of under-5 cancer mortality was higher in not only adverse but normal births.
Conclusion
Social inequalities must be addressed to reduce the disparity in cancer mortality of children under 5 years old.

Keyword

Under-5 Cancer Mortality; Parental Social Class; Social Inequalities; Socioeconomic Status

Figure

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  Fig. 1 Five-year Kaplan-Meier survival curves for children under 5 years with cancers by parental education and employment. The Statistics Korea, 1995–1999 birth cohort.

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  Fig. 2 Five-year Kaplan-Meier survival curves for children under 5 years with cancers by parental education and employment. The Statistics Korea, 2010–2014 birth cohort.

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