The burden of treatment-resistant depression: A systematic review of the economic and quality of life literature.

Background: Major depressive disorder (MDD) is a global public health concern. In particular, treatment-resistant depression (TRD) represents a key unmet need in the management of MDD. A systematic review of the epidemiological and economic literature on the burden associated with an increasing number of treatment steps due to TRD/non-response within an MDD episode was performed to quantify the burden of TRD.

Methods: Studies were identified in the PubMed/Medline databases through April 27th, 2017. Articles were limited to full-length peer-reviewed journal publications with no date restrictions. Economic and patient health-related quality of life (HRQoL) data on non-response by the number of treatment steps were quantified and, where appropriate, compared across studies; otherwise, comparative data within studies were reported.

Results: The 12 studies on economic burden found an association between increasing levels of TRD/non-response and elevations in direct and indirect costs. Likewise, the 19 studies studying HRQoL burden found that increasing levels of TRD/non-response correlated with reduced patient HRQoL and health status.

Limitations: TRD is defined inconsistently, which results in notable heterogeneity between published studies and poses methodological challenges for between-study comparisons. It is unknown if the increased economic and patient HRQoL burden are due to factors associated with TRD/non-response in addition to those due to depression persistence or severity.

Conclusions: A consistent trend was observed such that medical costs increased and patient HRQoL and health status decreased by increasing level of TRD/non-response within an MDD episode. These findings highlight the need for improved therapies for TRD to help reduce disease burden.