Trial-based economic evaluation of a multicomponent positive psychology intervention for euthymic patients with...

To date, no study has evaluated the cost-effectiveness of positive psychology interventions (PPI) for people with bipolar disorder (BD). This study evaluates the cost-effectiveness of the multicomponent PPI "Living well with bipolar disorder" for people with BD in the euthymic phase, compared to treatment as usual (TAU) alone.

96 participants were included in the study, with 53 randomized to the intervention group. Utility scores (EQ-5D-5L), well-being (MHC-SF), healthcare costs, productivity losses, and patient and family costs were assessed at baseline, 6 months and 12 months. Incremental cost-utility (quality-adjusted life-years (QALYs)) and cost-effectiveness ratios (costs per additional responder to treatment using MHC-SF scores) were estimated. Non-parametric bootstrapping (5000 repetitions) was used to assess uncertainty. Sensitivity analyses were conducted to test robustness.

The intervention led to an estimated incremental cost difference of €691 (95 % CI: -€2128; €3458) and 0.04 (95 % CI: -0.01; 0.08) incremental QALYs, which results in an ICUR of €19,669 per QALY gained. The probability of cost-effectiveness was ∼70 % considering a willingness-to-pay of €50,000 per QALY. Incremental treatment response was estimated at 0.12 (CI: -0.06; 0.30), resulting in an ICER of €5624 per additional responder. Sensitivity analyses indicated similar results.

Results indicate that the PPI "Living well with bipolar disorder" for patients with BD in the euthymic phase is likely to be cost-effective, introducing small but improved health outcomes against additional costs. Despite study limitations and the need for further research, results support the inclusion of this PPI in the spectrum of available treatments for BD. PRéCIS: Positive Psychology interventions in addition to treatment as usual for patients with Bipolar Disorder are more effective and more costly than treatment as usual alone.