OBJECTIVES: Because incidence-based cost of illness (COI) study requires long-term data to identify the onset of the disease and to follow up heath care utilization after the onset, it is difficult to carry out. To overcome such limitation, we estimated acute and maintenance-state costs of hematopoietic stem cell transplantation (HSCT) using one-year claims data.

METHODS: Pooling the yearly sample claims records of National Health Insurance data from 2016 to 2018, we identified those receiving HSCT (HSCT group) in each year if they had the procedure code of ‘X5*’ (i.e., HSCT). The Post-HSCT group is defined as those without ‘X5*’ code but with diagnosis code of ‘Z948’, referring to the state of having received HSCT. For each patient, the monthly utilization and cost data after the first appearance of procedure or diagnosis code were developed. Mean monthly utilization and costs were computed using monthly values available from each patient.

RESULTS: On average, allogeneic HSCT (n=40) and autologous HSCT group (n=86) had 4.28 and 4.31 hospitalizations during the year of transplantation. Average length of stay (LOS) per year was 59.25 and 38.59 days, respectively. The mean number of hospitalization and LOS in the Post-HSCT group was 3.93 and 44.11 days for the 98 allogeneic patients and 1.44 and 10.54 days for the 237 autologous patients. The expenditure of the first month after receiving the HSCT was highest (18,584.85 USD for the allogeneic patients and 25,136.43 USD for autologous patients) and it is gradually dropped by 11th month following transplantation. The medical cost of the Post-HSCT group did not show any tendency during a year (mean: 2,764.68 USD/month for the allogeneic and 1,098.67 USD/month for the autologous patients).

CONCLUSIONS: Our study shows the possibility of conducting incidence-based COI study based on cross-sectional claims data.