Type I Diabetes is the Main Cost Driver in Autoimmune Polyendocrinopathy

Autoimmune polyendocrinopathy (AP), a chronic complex orphan disease, encompasses at least two autoimmune-induced endocrine diseases.

To estimate for the first time total, indirect and direct costs for patients with AP, as well as cost drivers.

Cross-sectional cost of illness study.

Academic tertiary referral center for AP.

146 consecutive, unselected AP patients.

Interviews pertaining to patients' socioeconomic situation covered a recall period of 12 months. Both the human capital (HCA) and the friction cost approaches (FCAs) were applied as estimation methods.

Direct and indirect annual costs, and sick leave and medication costs.

AP markedly impacts healthcare expenses. Mean overall costs of AP in Germany ranged from €5 971 090 to €29 848 187 per year (HCA). Mean indirect costs ranged from €3 388 284 to €16 937 298 per year (HCA) while mean direct costs ranged from €2 582 247 to €12 908 095/year. Mean direct costs per year were €1851 in AP patients with type 1 diabetes (T1D, 76%) and €671 without T1D, which amounts to additional direct costs of €1209 for T1D when adjusting for concomitant autoimmune disease (95% CI = €1026-1393, P < 0.0001). Sick leave cost estimates for AP patients with T1D exceeded those without T1D by 70% (FCA) and 43% (HCA), respectively. In multiple regression analyses, T1D predicted total and direct costs, medication costs and costs for diabetic devices (all P < 0.001). Overall, AP patients with T1D were 54% (FCA) more expensive than those without T1D.

Public health socioeconomic relevance of AP was demonstrated, with T1D as main cost driver.