Cost-effectiveness and Budget Impact of Specialized Psychotherapy for Borderline Personality Disorder: A Synthesis of the Evidence.

Background: Specialized outpatient psychotherapy for patients with borderline personality disorder (BPD) is expected to reduce their use of other health care resources. It is currently unknown to what extent the costs of providing these interventions can be expected to be offset by a reduction in other health care costs in the Netherlands. To establish the cost-effectiveness and budget impact of specialized outpatient psychotherapy, the estimated incremental costs are synthesized with the estimated incremental effects. We have developed a method for the synthesis of all relevant evidence on clinical effectiveness as well as health care resource use.

Aim of the study: The aim of this article is to present a method for the synthesis of evidence for cost-effectiveness and budget impact analysis with a specific application to specialized outpatient psychotherapy for borderline personality disorder in the Netherlands.

Methods: A systematic search of the English-language literature is performed to retrieve evidence on the clinical effectiveness and the health care resource use following 12 months of specialized outpatient psychotherapy for borderline personality disorder. The available evidence is used as an input for a model-based economic evaluation. Simulated patient-level data are used to provide overall estimates of the incremental costs and incremental effects, which serve to assess the cost-effectiveness and budget impact of specialized outpatient psychotherapy for borderline personality disorder in the Netherlands.

Results: The results indicate that specialized outpatient psychotherapy for BPD can be considered cost-effective and that its scaling up to Dutch national level would require an investment of 2.367 million (95% C.I.: 1,717,000 - 3,272,000) per 1,000 additional patients with BPD. Sensitivity analyses demonstrated the robustness of our findings in light of several uncertain components and assumptions in our calculations, but also their sensitivity to the choice of included studies based on the comparator condition and the assumption of high intervention costs.

Discussion: We present a method for the synthesis of evidence from different types of studies in a way that respects the uncertainty surrounding those findings. Limitations of the study pertain to the inclusion of findings from studies with suboptimal designs, the transferability of research findings, and uncertainty regarding the time horizon considered. More research is needed on the sensitivity of our findings to the choice of included studies based on the comparator condition.

Implications for health care provision and use: THE results suggest that the provision of specialized outpatient psychotherapy for BPD leads to a reduction in other health care resource use. Overall, the results are promising and encourage future studies on aspects that are currently still uncertain.

Implications for health policies: The results may support policy makers in deciding whether or not to allocate health care budget for the provision of specialized outpatient psychotherapy for patients with BPD in the Netherlands.

Implications for further research: The results provide important directions for future research. This includes the need for future studies to make a comparison between specialized outpatient psychotherapy and treatment as usual and to have longer follow-up time.