Disparities in short-term and long-term all-cause mortality among Korean cancer patients with and without preexisting disabilities: a nationwide retrospective cohort study

Abstract

This study was conducted in order to determine whether a gap exists between cancer patients with disabilities and those without disabilities with regard to short-term and long-term all-cause mortality in Korea. The National Health Insurance claims database and the National Disability Database were used for performance of analyses. We identified 93,758 cancer patients (age, >20 years) who were diagnosed as cancer according to ICD-10 and who underwent treatment between January 1, 2000 and December 31, 2000. To distinguish between short-term and long-term survivorship outcomes, we performed survival analysis of short-term (<5 years) all-cause mortality for cancer patients and then confined our analysis to 5-year cancer survivors in order to assess the impacts of disability on long-term all-cause mortality. All analyses were performed according to gender, type of cancer, and type of disability, respectively, when cell sizes were large enough. Compared with the nondisability group, neither male nor female cancer patients with disabilities showed higher short-term (<5 years) all-cause mortality. When we confined our analysis to 5-year cancer survivors, both male (hazards ratio (HR), 1.48; 95% confidence interval (CI), 1.33-1.66) and female (HR, 1.53; 95% CI, 1.28-1.83) patients with prediagnosis disability had higher long-term all-cause mortality than those in the nondisability group. Male patients with impaired communication (HR, 1.24; 95% CI, 1.07-1.44) and female patients with internal disability (HR, 2.20; 95% CI, 1.42-3.42) had higher short-term (<5 years) all-cause mortality than those without these disabilities. Among both male (HR, 1.56; 95% CI, 1.38-1.75) and female (HR, 1.54; 95% CI, 1.28-1.86) 5-year cancer survivors, impaired mobility showed a significant association with a higher long-term mortality. This study raises concerns with regard to disability-related disparities in cancer outcome among long-term cancer survivors. Further attention and effective collaborative efforts are required for improvement of survival and quality of care for long-term cancer survivors.