The cost-of-illness and burden-of-disease of treatment-resistant depression in Austria.

Background: Treatment-resistant depression (TRD) in major depressive disorder (MDD) is most commonly defined as the failure to respond to at least two antidepressant (AD) treatments of adequate duration and adherence. While the health care utilization (RU) and costs of patients with MDD are well documented, little is known about patients with TRD. Therefore, the aim of this study was to determine the direct medical RU of complex therapy pathways and to analyze the total cost-of-illness and the burden-of-disease in Austria.