Cost-effectiveness analyses of augmented cognitive behavioral therapy for pharmacotherapy-resistant depression at secondary mental health care settings

Aim Pharmacotherapy is the primary treatment strategy in major depression. However, two-thirds of patients remain depressed after the initial antidepressant treatment. Augmented cognitive behavioral therapy (CBT) for pharmacotherapy-resistant depression in primary mental health care settings proved effective and cost-effective. Although we reported the clinical effectiveness of augmented CBT in secondary mental health care, its cost-effectiveness has not been evaluated. Therefore, we aimed to compare the cost-effectiveness of augmented CBT adjunctive to treatment as usual (TAU) and TAU alone for pharmacotherapy-resistant depression at secondary mental health care settings. Methods We performed a cost-effectiveness analysis at 64 weeks, alongside a randomized controlled trial involving 80 patients who sought depression treatment at a university hospital and psychiatric hospital (one each). The cost-effectiveness was assessed by the incremental cost-effectiveness ratio (ICER) that compared the difference in costs and quality-adjusted life years, and other clinical scales, between the groups. Results The ICERs were JPY -15 278 322 and 2 026 865 for pharmacotherapy-resistant depression for all samples and those with moderate/severe symptoms at baseline, respectively. The acceptability curve demonstrates a 0.221 and 0.701 probability of the augmented CBT being cost-effective for all samples and moderate/severe depression, respectively, at the threshold of JPY 4.57 million (GBP 30 000). The sensitivity analysis supported the robustness of our results restricting for moderate/severe depression. Conclusion Augmented CBT for pharmacotherapy-resistant depression is not cost-effective for all samples including mild depression. In contrast, it appeared to be cost-effective for the patients currently manifesting moderate/severe symptoms under secondary mental health care.