Direct medical costs associated with diabetes in the year of mortality: A population-based patient-level analysis

Abstract

Objectives : Estimates of direct medical cost associated with diabetes-related complications in the event and subsequent years have been quantified but costs in the mortality year have never been reported. This study aimed to estimate the direct medical costs of patients with diabetes mellitus (DM) in the year of mortality and the year before mortality. Methods : We analyzed a population-based, retrospective cohort study including all adults with DM managed under public sector between 2009 and 2013 in Hong Kong. Individuals died between January 1, 2010 and December 31, 2013 were included in analysis. Annual direct medical costs in year of mortality and the year before mortality per patient were analyzed by gender, the presence of comorbidities, the presence of diabetic complications (heart disease, stroke, diabetic nephropathy, or diabetic retinopathy), and primary cause of death. Results : A total of 6,919 subjects met the inclusion criteria for analysis. The commonest cause of death among DM patients was neoplasms (2261, 32.7%), followed by diseases of respiratory system (1725, 24.9%) and diseases of circulatory system (1113, 16.1%). On average, the direct medical costs in the year of death were 2.075 times higher than those in the year before death (US$23,256.1 vs US$11,205.2, p<0.001). Female patients had slightly higher costs in the year of mortality (US$23,337.2 vs US$23,172.8) and the year before mortality (US$11,261.5 vs US$11,147.3) than male patients. The increase in Charlson index was associated with greater costs in the mortality year. Patients with complications had higher costs in the year of mortality (US$27,500.6 vs US$21,982.5) and before the year of mortality (US$16,905.5 vs US$9494.7) than those without. Conclusions : This analysis provided new evidence on incorporating a one-off direct medical cost in the mortality year, and refining total cost estimation for studies on costing and cost-effectiveness analyses of health interventions for diabetes.