The Association of Household Income, Healthcare Utilization, and Survival of Catastrophic Illnesses Patients: Using ESRD and Cancer as Examples

Abstract

Objectives: To investigate the association of household income and healthcare utilization as well as survival status of patients with catastrophic illnesses under the NHI system in Taiwan. Methods: Data from the ”Survey of Family Income and Expenditure” (2003 to 2006) and the ”Registry of patients with catastrophic illness” were first linked to identify subjects. Patients with cancer or end stage renal disease (ESRD) holding only one NHI catastrophic illness card were included in this study. Information related to healthcare utilization was obtained from NHI claims data (2002 to 2007) and survival data was obtained from the ”National Registry of Deaths” (2003 to 2009). Negative binominal regression, multiple regression, and the Cox proportional hazard model were used to analyze the relationships among healthcare utilization, survival, and socioeconomic variables. Results: Regarding the healthcare utilization, the average length of stay (ALOS) of ESRD patients in the highest income bracket was 8.987 days longer than that of patients in the lowest bracket (p＜0.05). Hemodialysis usage, the number of outpatient visits and hospitalizations presented no correlation with household income. Among cancer patients in the highest income bracket, the IRRs of outpatient visits and hospitalization were 1.18 (p＜0.05) and 2.11 (p＜0.001), respectively. The ALOS of those in the highest income bracket was 11.36 days longer than that of patients in the lowest income bracket (p＜0.001). With respect to survival status, male ESRD patients had a higher mortality than females (HR=1.82, p＜0.05). Among cancer patients, being males (HR=1.66, p＜0.05) and in the highest income bracket had higher mortality (HR=1.6, p＜0.05), those with the highest education level had lower mortality (HR=0.52, p＜0.05). Conclusions: The relationship between household income and healthcare utilization varied according to type of diseases. Income level was positively associated with healthcare utilization among cancer patients while patients in the highest income bracket had higher mortality. But the association was not significant among ESRD patients. Future researchers can conduct further analyses on other catastrophic illnesses.