OBJECTIVES: Indirect costs reflect loss of productivity and its prediction over time measures the burden of the disease from a societal perspective. In the IQVIA Core Diabetes Model (CDM) v10.0 two approaches are available for indirect cost prediction: human capital approach (HCA) and Friction method (FM). Furthermore, 3 options to handle indirect costs due to mortality are available: in all cases of death, costs are excluded (option1), included for patients dying before retirement age (option2), and same as option2 but excluding for patients dying before working age (option3). This study compares total costs and net monetary benefits (NMB) using different approaches/options in CDM.

METHODS: Eighty-year analyses were performed on a type-1 diabetes cohort with a baseline age of 12 years and hemoglobin A1c of 8%. Treatment effect of -1%-point in HbA1c (intervention) was compared to no treatment (comparator). The Pittsburgh 2018 cardiovascular risk equation was used.

RESULTS: Predicted quality adjusted life years were 24.28 in intervention and 22.85 in comparator. Using the HCA with option1, predicted total costs were €199,964 in intervention and €233,357 in comparator, and NMB was €76,383. Comparing option2 and option3 with option1, total costs increased by €72,781 and €69,080 in intervention, and €80,619 and €76,399 in comparator, and NMB increased to €84,221 and €83,702, respectively.

Using the FM, total costs are slightly lower for option 1 (intervention= €198,502; comparator= €230,854). Including indirect costs of mortality (option3) hardly increased total costs (€1,077 increase in intervention and €1,185 increase in comparator)

CONCLUSIONS: Including indirect costs due to mortality increases the total costs considerably and increases the value of money of the better therapy. Including mortality also before the age of first salary increases costs further, however, has only a small additional impact on cost-effectiveness results. The impact of including mortality in the FM barely impacts final outcomes.