OBJECTIVES: This study assessed major depressive disorder (MDD) and treatment-resistant depression (TRD) patient and carer health utilities in the UK. MDD is a recurrent, highly-prevalent condition associated with decreased patient well-being and significant healthcare costs. TRD is MDD that has not responded to ≥2 adequate oral antidepressant treatments within the same depressive episode. Health utilities for TRD, non-treatment-resistant MDD and for those achieving remission post-TRD are needed to support reimbursement decisions for new TRD treatments.

METHODS: This cross-sectional observational study recruited participants through 10 UK primary care and specialist mental health services, across five mutually-exclusive cohorts: Patients with symptomatic MDD (not treatment-resistant, Patients-MDD), patients with symptomatic TRD (Patients-TRD), Patients with TRD in remission (Patients-Remission-TRD), carers of Patients-TRD (Carers-TRD) and carers of Patients-Remission-TRD (Carers-Remission-TRD). Participants completed EQ-5D-5L among other validated measures, which for patients included the Patient Health Questionnaire-9 (PHQ-9) to identify sub-groups that aligned with depressive symptom severity inclusion criteria of two recent TRD clinical trials (TRANSFORM-1, TRANSFORM-2). Moderate to severe depression was defined as PHQ-9 ≥17.8 (equivalent to Montgomery-Åsberg Depression Rating Scale [MADRS] ≥28) and remission as PHQ-9 ≤9.4 (equivalent to MADRS ≤12). Carer eligibility was confirmed by screening.

RESULTS: Most participants in all groups were female (66-75%). Patients’ mean ages (years) were Patients-MDD 37.9 (n=29); Patients-TRD 47.9 (n=35); Patients-Remission-TRD 57.3 (n=3). Mean (95% confidence intervals) utility was lower for Patients-TRD (0.354 [0.276–0.432]) versus Patients-MDD (0.629 [0.551–0.706]; P<0.001) and for Carers-TRD (0.799 [0.750–0.847], n=79) versus Carers-Remission-TRD (0.921 [0.879–0.962], n=20; P=0.020); the Patients-Remission-TRD sample was too small for statistical comparison with Patients-TRD.

CONCLUSIONS: These health utilities quantify the added burden for patients with TRD above that for MDD. Recruitment challenges limited data on patients with TRD in remission. TRD also impacts carers’ quality of life, which significantly improves for carers of patients who achieved remission.