Societal costs of personality disorders: A cross-sectional multicenter study of treatment-seeking patients in mental health services in Norway.

Objective: There is a relatively small body of research on the cost-of-illness of personality disorders (PDs). Most studies only include borderline PD. The aim of this study was to investigate mean societal costs, including its components, (direct) health service costs and (indirect) productivity loss, among treatment-seeking patients with the broad range of all PDs according to the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM-5).

Methods: Cross-sectional data from 911 patients diagnosed with at least 1 PD were retrieved from the quality register of the Norwegian Network for Personality Disorders-a collaboration of PD treatment units within specialist mental health services. The patients were referred in the time period 2017-2020. Estimation of costs was based on a bottom-up approach, using information from a structured interview covering the 6-month period before assessment, whereas unit costs were retrieved from public reports, public records, or public agencies. The human capital approach was used to calculate productivity loss. Diagnoses were determined by semi-structured diagnostic interviews (Structured Clinical Interview for DSM-5-PD [SCID-5-PD]).

Results: The mean societal costs were €20.260 during the 6-month period before specialized treatment. The largest cost component was productivity loss (65%), whereas health service costs constituted 35%. The main contributors to societal costs from the underlying health service cost components were inpatient treatment (20.5%) and individual outpatient treatment (10.5%).

Conclusion: Societal costs were substantial among treatment-seeking patients with the broad range of DSM-5 PDs, comparable to the societal costs of schizophrenia, and significantly higher than the societal costs of both depression and anxiety disorders. The cost estimates converged with recent, register-based cost-of-illness studies of different PDs but exceeded previous findings from other bottom-up studies. Furthermore, the results underscore the importance of implementing effective and specialized treatment for patients with a broad range of PDs, not only to alleviate individual suffering but also to reduce the level of societal costs. The emphasis on productivity loss as a main contributor to the overall societal costs is substantiated, hence underlining the relevance of interventions focusing on improving occupational functioning.