J Korean Med Sci.  2024 Apr;39(12):e130. 10.3346/jkms.2024.39.e130.

Social Inequities in the Survival of Liver Cancer: A Nationwide Cohort Study in Korea, 2007–2017

• Son M
• Kim HR
• Choe SA
• Song SY
• Lim KH
• Ki M
• Heo YJ
• Choi M
• Go SH
• Paek D

• KMID: 2554217
• DOI: http://doi.org/10.3346/jkms.2024.39.e130

Abstract

Background
To analyze the effects of socioeconomic status (type of insurance and income level) and cancer stage on the survival of patients with liver cancer in Korea.
Methods
A retrospective cohort study was constructed using data from the Healthcare Big Data Platform project in Korea between January 1, 2007, and December 31, 2017. A total of 143,511 patients in Korea diagnosed with liver cancer (International Classification of Diseases, 10th Revision [ICD-10] codes C22, C220, and C221) were followed for an average of 11 years. Of these, 110,443 died. The patient’s insurance type and income level were used as indicators of socioeconomic status. Unadjusted and adjusted hazard ratios (HRs) and 95% confidence intervals (CIs) were calculated using a Cox proportional hazards regression model to analyze the relationship between the effects of sex, age, and cancer stage at first diagnosis (Surveillance, Epidemiology, and the End Results; SEER), type of insurance, and income level on the survival of patients with liver cancer. The interactive effects of the type of insurance, income level, and cancer stage on liver cancer death were also analyzed.
Results
The lowest income group (medical aid) showed a higher risk for mortality (HR (95% CI); 1.37 (1.27–1.47) for all patients, 1.44 (1.32–1.57) for men, and 1.16 (1.01–1.34) for women) compared to the highest income group (1–6) among liver cancer (ICD-10 code C22) patients. The risk of liver cancer death was also higher in the lowest income group with a distant cancer stage (SEER = 7) diagnosis than for any other group.
Conclusion
Liver cancer patients with lower socioeconomic status and more severe cancer stages were at greater risk of death. Reducing social inequalities is needed to improve mortality rates among patients in lower social class groups who present with advanced cancer.

Keyword

Social Inequalities Liver Cancer Death; Social Class; Type of Insured; Medical Aid; Premium; Income; SEER

Figure

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  Fig. 1 Survival probability according to the type of insurance, income level, and cancer stage in all, male, and female liver cancer patients (ICD-10 code C22).ICD-10 = International Classification of Diseases, 10th Revision, SEER = Surveillance, Epidemiology, and the End Results.

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  Fig. 2 Survival probability according to the type of insurance, income level, and cancer stage in all, male, and female hepatocellular cancer patients (ICD-10 code C220).ICD-10 = International Classification of Diseases, 10th Revision, SEER = Surveillance, Epidemiology, and the End Results.

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  Fig. 3 Survival probability according to the type of insurance, income level, and cancer stage in all, male, and female intrahepatic cholangiocarcinoma patients (ICD-10 code C221).ICD-10 = International Classification of Diseases, 10th Revision, SEER = Surveillance, Epidemiology, and the End Results.

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